Note: Descriptions are shown in the official language in which they were submitted.
5jZ sy--13~ ~r.
ANTIBACTERIAL AGENT
-- .
The present invention provides for the stereoselective total
synthesis of certain novel substituted ~ 2'3-1,4-morpholine-
2-carboxylic ~cids possessing ~ fused ~-lactam ring in
the 1,6-position and carrying a substituent cis to carbon
5 in the 7-position o the fused r~ng ~ystem represented
b~ the general formula
. .
H H 5
. ~4
3Q
C02H
. .
whexein Q i8 hydrogen, alkyl, aralkyl or -CH2COOZ
: ~here Z i8 hydrogen or the residue of an ester group
~nd X i9 azido, amino or acylamino. When X is acyl-
; amlno, these ~clds (and their pharmaceutically accept-
.able ~alts and physiologically hydrolyzed esters) are
potent antibacterial agents.
.~ Al~o included in thi3 invention are various novel
intermediates u3eful in preparing th~ active ~-lactam
dérivatives described aboYe and various processes for
the production of the intermediate~ and act~ve ~mpounds.
r:
'SZ
The compounds having the above general formula
represent a new fam~ly of ~-lactam anti~iotic~. They
can be considered n~clear analogs of cephalosporin~ in
whlch the sulfur atom of the dihydrothiazine ring i8
repl~ced by an oxygen atom and shifted from po8it$0n
5 to position 4 of the ~-lactam ring system ~8 numbered
in the formula above.
~owever, since 8heehan has u~ed the term 0-cepham for
~he structure
. .
: ~ ~ 2
` , ~ ~ ~ 3
0-Cepham
.
.
. ~ .
~J.C. Sheehan and M. Dad~c, J. Heterocyclic Chem., 5,
770 (1968?~, we propose the use of the term 0~2-
18Ocepham for the ba8ic system h~ving the forMul~
"'`
,~ 1
: t 6"~
.. ~ ~ 0 2
The numerical prefi~ lndicate~ the position of eh~
hetero-at~m,
,
Z52
.
There is thus provided by the present invention
7; . the novel 0-2-isocephem compounds having the formula
H2
H H / ~
R--NH--C--C 0
I I I
C - N
~2~
wherein R ic an acyl group gnd Q is hydro~en, alkyl,
~ralkyl or -C~ ~OOZ in which Z is hydrogen or the residue
of an ester group and easily cleavable esters and
pharmaceutically acceptable salts thereof.
The acyl group R can be chosen from a ~ide variety
of organic acyl radicals which yield products of
improved properties and is preferably an acyl radical
which is contained in a naturally occurring or bio-
synthetically, ~emi-~ynthetically or totally-synthet-
ically active N-acyl derivative of 6-aminopenicillanic
~cid or 7-aminocephalosporanic acid. Examples o~
suitable acyl groups are deflned in the following
general formulae, but it should be noted that thls
i8 not ~ntended to be an exhaustive list of all the
possible acyl groups which may be used~
(i) RaCnH2
where Ra is aryl (carbocyclic or heterocyclic), sub-
s~ituted aryl, cycloalkyl, substituted cycloalkyl)
~ ' ~
11~25Z
' .
cycloalkenyl, substituted cycloalkenyl or a nonaromat~c
or mesoionic heterocyclic group, and n is an integer
fsom 1-4. The preferred Ra substituents are ~a) aryl
seleeted from phenyl, 2-thienyl, 3-th~enyl, furyl, 4-
i80xazalyl, pyridyl, tetrazolyl, sydnone-3 or -4,
~ im~dazolyl, naphthoyl, quinoxalinyl, triazolyl, iso-
thiazolyl, thiadiazolyl, thiazolyl, oxazolyl, oxadiazolyl,
pyrazolyl, furazan, pyrazinyl, pyrimidinyl, pyridazinyl
or triazinyl; ~b) sub6tituted aryl in which the aryl
groups mentioned above under (a) are substituted by
one or more radicals selected from chloro, bromo, iodo,
fluoro, nitro, amino, cyano, (lower)~lkanoyloxy, (lower)-
alkanoyl, (lower)alkoxyamino, (lower)alkoxy, (lower)-
alkyl, (lower)alkylamino, hydroxy, guanidino, (lower)-
alkylthio, carboxy, phenyl, halophenyl, trifluoromethyl,
di(lower)alkylamino, sulfamyl, (lower)alkanoylamino,
. phenyl(lower)alkylamido, cycloalkylamino, allylamido
morpholinocarbonyl, pyrrolidinocarbonyl, piperidinocar~
bonyl, tetrahydropyridino, furfurylamido or N-alkyl-N-
anilino; (c) C3-C12 cycloalkyl; (d) substituted C3-C12
cycloalkyl where the substituent~ are one or more radicals
selected from chloro, bromo, fluoro, iodo, nitro, trifluoro-
methyl, Cl-C4 alkyl, Cl-C4 alkylamino, Cl-C2 alkoxy or
am~no; (e) C3-C12 cycloalkenyl, said cycloalkenyl group
having 1 or 2 double bonds; and (f) substi~uted C3-C12
SZ
cycloalkenyl, said cycloalkenyl group having 1 or 2
double bonds and being substituted by one or more
radicals selected from chloro, bromo, fluoro, iodo,
nitro, trifluoromethyl, Cl-C4 alkyl, Cl-C4 alkylamino,
Cl-C2 alkoxy or amino. The most preferred Ra groups
are phenyl; phenyl substituted by one or more radicals
selected from chloro, bromo, iodo, fluoro, nitro, amino,
(lower)alkyl, guanidino, (lower)alkylthio, cyano, (lower)-
alkoxy, sulfamyl, (lower)alkylamino, hydroxy, acetoxy,
or trifluoromethyl; 2-thienyl; 3-thienyl; tetrazolyl;
sydnone -3; sydnone -4; furyl; isothiazolyl; thiadiazolyl
optionally substituted with phenyl; oxadiazolyl optionally
substituted with phenyl; thiazolyl; imidazolyl; triazolyl;
oxazolyl; pyridyl; furazan optionally substituted at the
3-position with methoxy; 4-isoxazolyl optionally sub-
stituted at the 5-position with methyl and at the 3-posi-
tion with phenyl or halophenyl; 1,4-cyclohexadienyl;
l-cyclohexenyl and l-aminocyclohexyl.
The most preferred acyl groups of this category
are those in which n is 1. Examples of this category
include phenylacetyl, halophenylacetyl, nitrophenylacetyl,
aminophenylacetyl, ~-(o-aminomethylphenyl)propionyl,
(lower)alkanoyloxyphenylacetyl (e.g. acetoxyphenylacetyl),
(lower)alkoxyphenylacetyl (e.g. methoxyphenylacetyl,
ethoxyphenylacetyl), (lower)alkylphenylacetyl (e.g. methyl-
phenylacetyl or ethylphenylacetyl), hydroxyphenylàcetyl
(e.g. o-hydroxyphenylacetyl), (lower)alkylaminophenyl-
acetyl (e.g. o-, m- or p- aminomethylphenylacetyl), o-
- 5
~a
$1~ZSZ
m- or p- guanidinophenylacetyl, o-carboxypheny~acetyl,
N,N-bis-(2-chloroethyl)aminophenylpropionyl, thien-2
and 3-ylacetyl, 2- or 3- furylace~yl, 1,2,5-thiadiazole-
3-acetyl, isoth~azolyl-4-acetyl, 4-isoxazolylace~yl,
l-cyclohexenylacetyl, 2-aminomethyl-1-cyclo~exenyl-
acetyl, l-aminocyclohexylacetyl, 1,4-cyclohexadienyl-
acetyl, 2-aminomethyl-1,4-cyclohexadienylacetyl,
pyridylacetyl, tetrazolyl~cetyl (other heterocyclic
groups of this type are disclosed in U.S. 3,81g,623
and 3,516,997) or a sydnoneacetyl group as disclosed
ln U.S. 3,681U328, 3,530,123 and 3,563,983. Other
groups of this type include 3-phenyl-5-chlorophenyl-
5-methylisoxazol-4-ylacetyl and 3-(2,6-dichloropheryl)-
5-methylisoxazol-4-ylacetyl or a group in which isox-
azolyl is replaced by isothiazole as disclosed in U.S.
3,551,440. Still other examples are o-, m- and p-
(2'-aminoethoxy)phenylacetyl (as disclosed in U.S.
3,759j905), 4,5-dimethoxycarbonyl-1,2,3-triazol-1-
ylacetyl or 4-cyano-1,2,3-triazol-1-yl-acetyl tas
disclosed in U,S, 3,821,206) and imidazol~ acetyl
(a 9 disclosed in U,S. 3,632,810;
--6--
ZSZ
(ii) CnH2n~1~~
where n is an integer fro~ 7, ~he alkyl group may
be straight or branched and, if desired, may be inter-
rupted by an oxygen or sulphur atom or substituted by,
e.g., a cyano group Examples of this group include
cyanoacetyl, valeryl, hexanoyl, heptanoyl, ethoxy-
carbonyl, octanoyl and butylthioacetyl. A preferred
acyl group is cyanoacetyl;
where n is an integer from 2-7. The alkenyl group
may be straight or branched and, if desired, may be
interrupted by an oxygen or sulphur atom. An example
of this group is allylthioacetyl;
( iv) Rb
Ra -O-c_co-
:. RC .,
where Ra is as defined under (i) and in addition may
be benzyl, Cl-C6 alkyl or (lower)alkoxycarbonyl and
Rb and Rc which may be the same or different each
represent hydrogen, phenyl, benzyl? phenethyl or Cl-C6
alkyl. The preferred Ra substituents in this category
; are benzyl, Cl-C6 alkyl, (lower)alkoxycarbonyl and those
mentioned under (i) as being preferred aryl, substituted
aryl, cycloalkyl (and subs~ituted cycloal~yl~ and
cycloal~enyl (and substltuted cycloalkenyl) groups.
The most preferr~d Ra group is phenyl. Examples of
this group include phenoxyacetyl, 2-phenoxy-2-phenyl-
)Z5Z
~cetyl, 2-phenoxypropionyl, 2-phenoxybutyryl, benzyloxy-
acetyl, 2-methyl-2-phenoxypropionyl, p-cresoxyacetyl,
p-~ethylthiophenox~acetyl and ethoxycarbonylacetyl;
',` tV) Rb
, ' RaS-C-CO_
., B.c
where Ra ig as defined under (i) and in addition may be
~ . benzyl or Cl-C6 alkyl and Rb and Rc have the meanings
; defined under (iv). The preferred Ra suhstituents in
thls category are benzyl, Cl-C6 alkyl and those mentioned
under (i) as being:preferred aryl, su~stituted aryl,
cycloalkyl (and substituted cycloalkyl) and cyclo-
~ alkenyl (and substituted cycloalkenyl) groups. The
:
: most preferred aryl groups of this type are those in
which Rb and Rc are hydrogen and Ra is phenyl; phenyl
aubstituted with one or more radicals selected from
chloro, bromo, iodo, fluoro, nitro, amino, (lower)-
alkyl, (lower)alkythio, cyano, (lower)allcoxy, (lower~-
alkyIamino, hydroxy, acetoxy or trifluoromethyl;
3-pysidyl; or ~-pyridyl;
(vi) RaX (CH2)mCO-
where Ra is as defined under (i) and in addition may
be benzyl, X is oxygen or sulphur and m ;.s an integer
r~ 2~5. The preferred Ra groups are benzyl and those
mentioned under (i) as being preferred aryl, substituted
aryl, cycloalkyl ~and substituted cycloalkyl) and
cycloal~enyl (and substituted cycloalkenyl) groups.
$1~Z:SZ
. .
An example of this gr~up is S-benzylthiopropionyl.
(vii) RaCO-
where Ra is as defined under (i). The preferred Ra
groups are those mentioned under (i) as being preferred
aryl, substituted aryl, cycloalkyl (and substituted
cycloalkyi) and cycloalkenyl (and substituted cyclo-
slkenyl) groups. The most preferred aryl groups of
this category are those in which Ra is phenyl; phenyl
~ubstituted with one or more radicals selected from
chloro, bromo, iodo, fluoro, nitro, amino, (lower)-
alkyl, tlower)alkylthio, cyano, (lower)alkoxy, (lower)-
~lkylamino, di(lower)alkylamino, hydr~xy, acetoxy or
trifluoromethyl, and mo~t preferably phenyl substituted
at the 2-position by carboxy or phenyl or at the 2- and
6-positions by methoxy; 2-ethoxynaphthoyl; 3-phenyl-
5-methylisoxazol-4-yl; 3-o-chlorophenyl-5-methylisoxazol-
4-yl; 3-(2,6-dichlorophenyl)-5-methylisoxazol-4-yl and
l-aminocyclohexyl. Examples of this group include 2,6-
dimethoxybenzoyl, benzoyl, 2-biphenylcarbonyl, 2-amino-
methylbenzoyl, 2-carboxybenzoyl-2-phenylbenzoyl, 2-
thienylcarbonyl, 3-thienylcarbonyl and 2-chlorobenzoyl;
tviii)
~ Ra-CIH-CO- or Ra-CH-CH2CO-
.. ' Y
where Ra is as de~ined under ~i) and Y is hydrazino,
guanidino, ureido, thioureido and substituted thioureido
(as disclosed in U S. 3,741,962), allophanamido (as
described in U.S. 3,483,188), 3-guanyl-1-ureido( as
,
_g_ ,
~n U.S 3,796,709), 3-(2-furoyl)ureido, cyanamino
(as in U.S. 3,796,709), 3-tbenzoyl~ureido, azido,
amlno, acylamino (e.g. carbobenzoxyamino), a group
obta~ned by reacting the amino group of the 7-side
chain with an aldehyde or ketone (e.g. ace~one, form-
aldehyde, acetaldehyde, butyraldehyde, acetylacetone,
methyl acetoacetate, benzaldehyde, salicylaldehyde,
methyl ethyl ketone or ethyl acetoa~etate), hydroxy,
etherified hydroxy, esterified hydroxy, carboxy,
esterified carboxy (as disclosed Eor example in U.S.
3,282,926, 3,819,601 and 3,635,9~1 and including
especially
-C--O ~ ), triazolyl,
.
tetrazolyl, cyano, halogeno, acyloxy (e.g. formyloxy
or (lower)alkanoyloxy), sulfo, sulfoamino or esterified
sulfo. The preferred Ra substituents are those ~.entioned
under (i) as being preferred aryl, substituted aryl,
cycloal~yl (and substituted cycloalkyl) and cycloalkenyl
(and substituted cycloalkenyl) groups, Preferred Y
subst~tuents are hydrazino; guanidino; ureido; substi-
~ted thioureido of the formula
RP
S Rq
in whLch RP is hydrogen or Cl~C~ alkyl and Rq is hydrogen,
' .
--10--
_ _., , , _ ._ . _ . _ . .. . .
Z5Z
Cl-Cg alkyl, C~-Cg alkenyl, phenyl, benzoyl, Cl-C8
Alkoxy- Cl-C8 alkyl, tcarbo-Cl-Cfi alkoxy) cl-c8 alkyl;
allophanamido; 3-guanyl-1-ureido; 3-(2-furoyl)ureido;
3-(benzoyl)ureido; azido; amino; a group obtained by
reactlng the amino group Y with acetone, formaldehyde,
acetaldehyde, butyraldehyde, acetylacetone, methyl
scetoacetate, benzaldehyde, salicylaldehyde, methyl
ethyl ketone or ethyl acetoacetate; hydroxy; etherified
hydroxy including espec~ally (lower)alkoxy, carboxy;
esterified carboxy including especially 5-indanyloxy-
cflrbonyl; triazolyl, tetrazolyl; cvano; cyanamino;
halogeno; formyloxy; (lower)alkanoyloxy; sulfo; or
sulfoamino. Examples of this group include ~-amino-
phenylacetyl; a-carboxyphenylacetyl; 2,%-dimethyl-5-oxo-
4-phenyl-1-im~dazolyl; a-amino-p-hydroxyphenylacetyl;
a-hydroxyphenylacetyl; a-formyloxyphenylacetyl and other
sryl groups of this type d~sclosed in U.S. 3,812,116 and
3,821,017; a-amino-a-~- or 3-thienylacetyl; a-amino-~-
~3-chloro-4-hydroxy)phenylacetyl; a-a~ino-a-(1,4-cyclo-
hexadienyl)acetyl; a-azidophenylacetvl; ~-amino-a-(l-
cyclohexenyl)acetyl; ~-carboxy-~-3-thienylacetyl; ~-amino-
-(3t5-dichloro-4-hydroxyphenyl~acetyl; ~-amlno-a-3- or 4-
or 5-isothiazolylacetyl tas in U.S. 3,579,506) and other
a-smino and n-hydroxy-heterocyclylacetyl groups as
dlsclosed for example ~n U.S. 3,821,207,
.,, . ~
~llg)Z5
~;
~ix) Re
Rd-C-Co_
Rf
where Rd, Re and Rf which may be the same or different
may each represent Cl-C6 alkyl, phenyl or substituted
phenyl. The preferred phenyl substituents are one or
more radicals selected from chloro, bromo, iodo, fluoro,
trifluoromethyl, nitro, amlno, cyano, (lower)alkanoyloxy,
(lower)alkanoyl, tlower)alkoxyamino, (lower)alkoxy,
(lower)alkyl, (lower)alkylamino, hydroxy, (lower)alkyl-
.
thio, carboxy, di(lower)alkylamino or sulfamyl. An
example of this group i8 triphenylmethylcarbonyl.
(x)
Ka-NH-C-
X
where R~ is ~s defined under (i) and in addition may be
hydrogen, Cl_c6 alkyl, halogen substituted Cl-C6 alkyl,
phenethyl, phenoxymethyl; benzyl or Ra-C- and X is oxygen
' O
- or sulphur. An example of such a group is Cl~CH2)~NHCO;
-' (x~)
,' ` CH2
(C\2)n /C\ O-
~CH2
where Y is as defined under (viii) and n is an integer
of 1-4. A most preferred Y substituent is amino. An
example of this group is l-aminocyclohexanecarbonyl
.
,
~`~ ~
$~ Z5Z
(xli) Aminoacyl, for example
RgCH (NH2 ) - (c~2 ) n
where n is an integer of 1-10, or
H2N-~nH2n~.r (CH2)mC
where m is zero or an integer from 1-10, ant n is
0, 1, or 2; Rg is hydrogen or an alkyl, aryl, aralkyl
or carboxy group or a group a~ defined under Ra in
(l) ~bove; and Ar is an arylene group, e.g. p-phenylene
or 1,4-naphthyle~e, Preferred aryl groups of the above
formulae are those in which Rg is hydrogen, (lower)-
alkyl, phenyl, benzyl or carboxy-~nd Ar is p~phenylene
or 1,4-naphthylene. Examples of such groups are
disclosed in U.K. 1,054,806. Examples of groups of
this type include p-aminopheny~acetyl and J-aminoadipoyl
derived from naturally occurring amlno acids and deriv-
~tives thereof, e.g. N-benzoyl-~ -aminoadipoyl;
(xiii) Substituted glyoxylyl groups of the
formula
Rh~CO~CO-
where Rh is an aliphatic, araliphatic or aromatic group.
, . .
The preferred Rh groups are 2-thienyl; 3-thienyl;
a-naphthyl; 2-phenanthryl or a mono-, di- or tri-
8ubstituted phenyl group, the substituents being
8elected from chloro, bromo, iodo, fluoro, amino,
di(lower)alkylamino, (lower)alkyl, (lower)alkoxy,
n~tro or (lower)alkanoylamino. Examples of this category
~re disclosed in U.S. 3,546,219 and 3,573,294. Included
, .. , _ . . .. .
~13LVZSZ
in this group are also the ~-carbonyl derivatives of the above
- substituted glyoxylyl groups formed for example with hydroxyl-
~ amine, semicarbazide, thiosemicarbazide, isoniazide or hydrazine;
:, , (xiv) Ra-CH-CO-
- I
NH
H-N-C-R
~ ' X'
. ~ where Ra has the meaning defined under (i), X is oxygen or sul-
. phur, X' ls oxygen or imino and R represents (lower)alkyl,
¦ cycloalkyl having 4,5,6 or 7 carbon atoms, monohalo(lower)alkyl,
dichloromethyl, trichloromethyl, (lower)alkenyl of 2-6 carbon
atoms,
R
Rk ~ ~ ~CR2)n~ ~ ~(CE~2) - Rk~
2N rO~ N~ N~N N 5, N
I
C3 3 ~ , N~
~_ -- Rk
- 14 -
~ ZSZ
H3C ~
~ O CH3
n is an integer from 0 to 3 inclusive and each of Rk
and R~ is hydrogen, nitro, di(lower)alkylamino, (lower)-
slkanoylamino, (lower)alkanoyloxy, Cl-C6 alkyl, Cl-C6
alkoxy, sulfamyl, chloro, bromo, iodo, ~luoro or tri-
fluoromethyl. The preferred Ra substituents are those
mentioned under (i) as being preferred aryl, substituted
aryl, cycloalkyl (and substituted cycloalkyl) and
cycloalkenyl (and substituted cycloalkenyi) groups.
Preferred acyl groups of this type are those in whlch
Ra is 2-thienyl; 3-thienyl; phenyl; or phenyl sub-
stituted by one or more radicals selected from nitro,
di(lower)alkylamino, (lower)alkanoylamino, amino,
hydroxy, (lower)alkanoyloxy, Cl-C6 ~lkyl, Cl-C6 alkoxy,
sulfamyl, chloro, bromo, iodo, fluoro or trifluoro-
methyl; .Y is oxygen; X' is oxygen or imino and Ri is
(lower)alkyl, phenyl, 2-thienyl, 3-thienyl, 2-furyl
or 5-nitro-2-furyl. The most preferred groups are
those of the above formula where Ra is phenyl, p-hydroxy-
phenyl, 2-thienyl or 3-thienyl; X is oxygen; X' is
oxygen, and Ri is phenyl or 2-~uryl~ Examples are
~isclosed in U.S. 3,687,949 and 3,646,024;
--15--
. _ . . . . _ .-- . . . _
25Z
:. , .
,
.- . ~
' ~XY) Ra-CH-C~- '
. . N~o
.
C~2-CO-
Ri ~ ~ or. RL-II NH-C~2CO-
. where Ra has the meaning defined in (i) and R~ has
the meaning defined in (-~iv). The preferred Ra
.
; sub~tituents are those mentioned under (i) as being
preferred aryl, substituted aryl, cycloalkyl (and
substituted cycloalkyl) and cycloal~enyl
- (and substituted cycloalkenyl) groups. Preferred Ri
' ' '
substituent~s include (lower)alkyl, dichloromethyl,
; . C4-C7 cycloalkyl, 2-thienyl, 3-thienyl, phenyl,
benzyl, halsbenzyl,
.
N~ C3
_ ~ N3 h C
. .
16-
. ~
ZS2
C6H5 ~ and ~ ~
Examples of this group are disclosed in U.S. 3,626,024
and 3,692,779;
(xvi)
Ra-CH-CO-
S-CrR
.. Il
where Ra has the meaning defined in (i) and Rl is (lower)-
al~yl, C3-C12 cycloalkyl, aryl (especially phenyl), a
. monocyclic heterocyclic radical having 5 or 6 atoms
exclusive of hydrogen which are C, S, N or 0, no more
han 2 atoms being other than C, or a substituted mono-
.. cyclic heterocyclic radical as defined above having
~` one or more substituents selected from halo, (lower)-
. ~lkyl, (lower)alkoxy or phenyl. Examples of this group
~re disclosed.in U.S. 3,778,436. Most preferred
groups are (lower)alkyl, phenyl, thienyl or furyl.
. A preferred class of acyl groups are those of the
f or~ula
Arl-CH~C-
-17-
ZSZ
wherein Ar' is a radical of the formula
. Rm Rm
; Rn ~ ~ , ~ or ~
in wh~ch Rm, Rn and R are alike or different and each
i8 hydrogen, hydroxy, (l~wer)alkyl, cyano, (lower)alkoxy,
. chloro, bromo, iodo, fluoro, trifluoromethyl, nitro,
.~ amino, (lower)alkylamino, di(lower).alkylamino, (lower)-
alkanoyl, (lower?alkanoyloxy such as p-ace~oxy or phenyl
and Y is amino or a group obtained by reacting the amino
.
group with acetaldehyde, formaldehyde or acetone, fluoro,
chloro, bromo, iodo, hydroxy, (lower)alkanoyloxy, carboxy,
guanidino, 3-guanyl-1-ureido, 3-(2-furoyl)-~ eido, 3-benzoyl-
ureidQ, sulfo, sulfoamino, ureido, thioureido, ~lower)-
koxY~ cyano, cyanamino or lndanyloxycar~onyl. Partl-
~ul~rly preferred Ar radicals are phenyl, p-hydroxyphenyl,
. 4-hydroxy-3,5-dichlorophenyl, 3-chloro-4-hydroxyphenyl,
o-, ~- or p- aminomethylphenyl, 2-thienyl, 3-thienyl,
l-cyclohexenyl and 1,4-cyciohexadienyl. Partic~larly
preferred Y groups are amino, hydroxy alld carboxy.
Set forth bel~w are formulae of the most preferred acyl
groups o this class:
,
~-CO- ; ~o_~C-CO~
-18-
'.
Cl Cl
H~ CH-CO- ~iO~ CH-CO- ;
2 Cl N~2
r~ -- , C~l--CO--
~S ~J NH2 I~H -CO -
NH2
~ CH-CO- ; ~\
\--J NH2 ~ CH-CO
~CH-CO- ;
OH
. , , CH-CO-
' ~S~ ~ ; ` ~ ;
,~ ~ S jl ICH-C:O-
0~
C3 ~CH CO- ; ~_CH-CO-
CH-CO- ~CH-CO-
25Z-
CH-CO- ; ~ CH-CO-
- COOH COOH
H-CO- and ~ CH-CO-
COOH C ~O
;' : ~=~0
, ' Of most interest are the acyl gr~ups Oe the above class
. where the acid ArCH(X)COOH is of the D-series.
: ~ Other particularly preferred acyl groups for the
compounds o~ ~ormula I are
. OCH3
N i C-CH2CO- . ; ~ CO- ;
OCH3
N N
! \ N CH CO ' N ~ SCH2CO-;
..
~CO-;
. where U and V sre alike or different and each is
hydrogen, chloso or fluoro;
-20-
1,.
25Z
. ~CH2CO- C3~H2C-
~H2CO~ CH2CO-
. N~
/ CH2CO-, ~ CH-CO-
H NH
:.:. O=C -N~l-C--O
. I
, . C6H5
~'
~ OCH2CO- ,<~ SCH2CO- '
:
CH2NH2
~H2CO- , Cl-C7 alkyl-CO- , .
~ ' .
~CO- ~ ~C8~CO_ ,
: ~L ~CH2CO-
CH2Co- , N~N
--21--
- )
)25Z
- Cl-C7 alkoxy-CO- . O~CO-
~112 .
~CH2C~ H-CH2CO-, ~-OCH2NHCO-
OH
O--C`--I--H ~--CN2CO-
~ ~ .
~ , ~ CO-
: . .
- ` . CH2NH2
,~co~ SCH2CO-
.
--22--
DIV. II
Thus this divisional application provides a process
for the preparation of an enol intermediate of the formula
N3 - _ / CH20SO2-(lower)alkyl
C C
O - N
IX C = CHOH
2R"
wherein R" is an easily cleavable ester selected from the
group consisting of benzhydryl, benzyl, p-nitrobenzyl,
p-methoxybenzyl, trichloroethyl, trimethylsilyl, phenacyl,
acetonyl, (lower)alkyl, triphenylmethyl, methoxymethyl, indanyl,
phthalidyl, pivaloyloxymethyl and acetoxymethyl; which process
comprises subjecting to acid hydrolysis a (lower)alkylsulfonyl
derivative of the formula
H H
N3 \_ _ CH2OSO2-(lower)alkY
O C N Hl / NX"
., \C'~ .
~ XVII C02R"
',"
wherein R" is as defined above and X" is the res~due of an
amine.
- 22(a) -
..,
Z52
.
The term "(lower)alkyl" as used herein means
both straight and branched chain alipha~ic hydrocarbon
radicals having from one to ten carbon atoms such as
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-
bu~yl, amyl, hexyl, 2-ethylhexyl, hep~yl, decyl, etc.
Similarly, where the term "(lower)" is used as part
of the description of another group, e g. "(lower)-
alkoxy", it reers to the alkyl portion of such group
which i~ therefore described above in connection
t with "(lower)alkyl".
The pharmaceutically acceptable salts referred
to above include the nontoxic carboxylic acid salts,
e.g. nontoxic metallic salts such as sodium, potassium,
caqcium and aluminum, the ammonium salt and salts with
nontoxic amines, e.g. trialkylamines, procaine,
dibenzylamine, N-~enzyl-B-phenethylamine, l-ephenamine,
N,N'-dibenzylethylenediamine, N-alkylpiperidine and
other amines which have been used to form salts of
peniciilins ~nd cephalosporins. When a basic group
i8 present, as when it occurs in the 7-acyl group,
the present invention also includes the pharmaceutically
acceptable acid addition salts, e.g. salts with mineral
acids such as hydrochloric, hydrobromic, hydroiodic,
phosphoric, sulfuric and salts with organic acids such
a8 maleic, acetic, citric, oxalic, succinic, benzoic,
tartaric, fumaric, mandelic, ascorbic and malic. The
-23-
_,, ) ! ~
Z5Z
term ;'pharmaceuticslly scceptsble salts" is also
meant to include nontoxic acid addition salts of
the eas~ly clea~able esters referred to above, The
compounds which contsin a bssic group in radical
R may also be pre~ent in the form of an ~nternal
salt, i.e. in the form of the zwitterion.
The easily cleavable esters referred to above
include ester groups which are removable by methods,
e.g. chemical or enzymatic hydrolysis, treatment with
chemical reducing agents under mild conditions,
irradiation with uttraviolet light or catalytic
hydrogenation, which do not result in any appreciable
destruction of the remaining portion of the molecule.
Examples of suitabIe esters include those disclosed
~n U.S. Patents 3,284,451 and 3,249,62~ ;7nd U.K.
Patents 1,229,453 and 1,073,530. Esters which have
been used previously in penicillin and cephalosporin
chemistry inclute for example benzhydryl, p-nitrobenzyl,
.
benzyl, trichloroethyl, silyl such as trimethyl~ilyl,
phenacyl, p-methoxybenzyl, acetonyl and
~lower)alkyl such as methyl, ethyl and t-butyl.
Particularly preferred easily cleavable esters are
` those whlch are hydrolyzed under physiological cond$-
tions such as pivaloyloxymethyl, acetoxymethyl and
methoxymethyl.
As the 0-2-isocephem compounds of the present
invention may possess one or more ssymmetric car~on
,~ .
-24-
) ?
-
252
. .
~
atoms, the invent~n includes all of the possible
enantiomeric and diastereomeric forms of the com-
pounds of the general formula I shown above.
Resulting mixtures of isomers can be separated into the
individual lsomers according to methods which are
known ~ se, e.g. fractional crystallization,
adsorption chromatography or other suitable separation
processes~ Resulting racemates can be separated into
the antipodes in the usual manner after introduction
of suitable salt-forming groupings, e.g.by formlng
a mixture of diastereoisomerlc salts with optically
active salt-forming agents, separating the mixture
~nto diastereoisomeric salts, and converting the
~:~ separated salts into the free compounds, or by
fractional crystallization from optically active
801vents.
It will be appreciated that certain of the
compounds of this invent~on exist in various states
of so~vation and the anhydrous as well as solvsted
form~ are within the scope of the invention.
. The free acid compounds of the above general formula
I whe~e R is acyl and physiolo~ically hydrolyzed
esters thereof together with the pharmaceutically
acceptable salts of such free acids and ester~ are
sctive antibacterial agents. The remaining compounds
of the above general formula I including salts thereof
.. . .
-25-
)
are valuable intermediates which can be converted
into the above-ment-~oned pharmacologically active
.compounds in a simple manner, for example, as
described below.
Preferred embodiments of the present invention
~re the 0-2-isocephem compounds having the formul~
: H H
. R-
.'' ' ' ~ ~ ~
02H
wherein W is hydrogen, alkyl, e.g. methyl, or aralkyl,
e.g. benzyl or phenethyl and R represents an acyl group,
and easily cleavable esters and pharmaceutically
acceptable salts thereof.
Preferred acids, esters and saltc of formula II are
those in whi.ch acyl group R is selected from the acyl
groups defined above under (L) to (xvi). The acyl groups
mentioned as being preferred groups within categories (i)
to (xvi) are also preferred in the compounds defined by
general formula II.
Mare preferred acids, esters and salts of formula
: II are those in which acyl group R is
~ Ar'-CH-C0-
: Y
;in which Ar' i8 a radlcal of the formula
Rm
Rn ~ ~ , ~ or
R
-26-
: ` )
Z52
in which Rm, Rn snd R are alike or different and each
` ~8 hydrogen, hydroxy, (lower)alkyl, cyano, (lower)alkoxy,
chloro, bromo, iodo, fluoro, trifluoromethyl, nitro,
amino, (lower)alkylamino, di(lower)alkylamino, (lower)-
alkanoyl, (lower)al~anoyloxy such as p-acetoxy or phenyl
and Y is amino or a group obtained by reacting the amino
group with acetaldehyde, formaldehyde or acetone, fluoro,
chloro, bromo, iodo, hydroxy, (iower)alkanoyloxy, carboxy,
guanidino, 3-guanyl-1-ureido, 3-(2-furoyl)ureido, 3-benzoyl-
ureido, sulfo, sulfo~mino~ ureido, thioureido, (lower~-
~lkoxy, cyano, cyanamino or indanyloxycarbonyl.
Other preferred acids, esters and salts of formula
re those in wh~ch R
Ar'-ClH-CO-
y .
wherein Ar' is phenyl, p-hydroxyphenyl, 4-hydroxy-~,5-
dichlorophenyl, 3-chloro-4-hydroxyphenyl, o-, m- or p-
- aminomethylphenyl, 2-thienyl, 3-thienyl, l-cyclohexenyl ~
or 1,4-cyclohexadienyl and Y i6 amino, carboxy or hydroxJ.
Other preferred compounds of formula II are those
where~n R is an ~cyl gro~p of the formula
,_
CH-CO- ~
I HO ~ CH-CO-
NH2
~1 Cl
~O ~ CH-CO- . ~
3H ' HO ~ C~-CO- '
~ NH2
-27-
zsz
I~S,~L CH-CO- ~ IH_CO_
NH2
C3CH_CO~ CH-CO-
~: CO , ~,L CH-Co_
OH
H ' ~H-CO-
OH
H CO- . ~ ICH-CO-
. COOH
.. .
~COOH ~ H-CO-
; COOH
\~CH-CO- J/--\
\--/ COOH W-CI H-CO ^ or
COOH
H-CO-
' C--O
;~
--28--
~LllOZ52
Other preferred compounds of formula II are those
whereln R is an 8Cyl group of the formula
OCH3
N--C-CH2CO- , ~ CO-
CH3
N - N
CH2CO- , /~\
N = C/ ~ SCH2-CO- '
.
U
CH
wherein U and V are ali~e or different and each i~
; hydrogen, chloro or ~luoro;
.
- ~CH2CO- ~--CH2CO-
~:H2CO- . ~>--.CH2CO-
.; . .
~ OCH2CO~ SCH2CO-
~.
!
r~ ,,
252
CH2~JH2
~CH2CO- ,Cl-C7 alkyl-CO-
~CO ~ ~CH2Co_
. OC2H5
:'
C1-C7 nlkoxy-Co_ ~ G~NH2
~CH2~CI-NH-CH2CO-, ~
; NH \=~OCH2NHCO- ' ,
N~ ~ i
' i, - . l~ jC-CH2CO-
H
.. I
OH
O--C--lC--H <~- CH2C0-
\N~
,
'
, . .
Z52
.
. CoOH C6H5
-, ~0- , ~CO- ~
. .
CO- ,~ CH-CO- or
, ,C~2NH2 ' O=C-N~-C=O
~SC~2CO- C6H5
. .
A most preferred group o~c~mpou~ds are those
-. ~ ac~ds defined by formula II wherein R is a-carboxy-
: . phenylacetyl, cyanoacetyl, a-amino-a-(p-hydroxyphenyl)-
. acetyl, a-amino-c-(3-chloro-4-hydroxyphenyl)acetyl,
. ~ . a-amLno-a-(3,5-dichloro-4-hydroxyphenyl)acetyl, a-
amino-~-(2-~hienyl)acetyl, ~-amino-a-(3-thienyl)acetyl,
. a-sm~no-a- (l-cyclohexenyl)acetyl, a-amino-~-(1,4-cyc;o-
hexadieny~)acetyl, a-hydroxyacety~, a-hydroxy-~-
(2-thienyl)acetyl, a-hydroxy-~-(3-thienyl)acetyt,
~.
-hydroxy-a-~l-cyclohexenyl)acetyl, c-hydroxy-Q-(1,4-
;~ . . cyclohexadienyl)acetyl, a-carboxy-c-(2-thienyl)acetyl,
~ ~-carboxy-a-(3-thienyl)acetyl, a-carbo~y-a-(l-cyclo-
-~ Xexenyl)acetyl, ~-carboxy-a-(1,4-cyclohexadienyl)-
-.: acetyl, ~-indanyloxycarbonyl-G-phenylacetyl, l-~lH)-
tctrazolyl, 4-pyridylthioacetyl, 2-thienylacetyt,
-31-
, . , .. _ . .. .___ ._ _ .. . . _ _ ... .. . .. ..
r-~ )
Z5Z
3-th~enylacetyl, l-cyclohexenyl~cetyl, 1,4-cyclo-
hexadienylacetyl, o-aminomethylphenylacetyl, l-amino-
cyclohexylcarbonyl, 2,6-dimethoxybenzoyl, sydnone-
~cetyl or -szidophenylacetyl, or a pharn~ceutically
ecceptable salt thereof,
Another most preferred group of compounds are the
D-lsomers of those acids defined by formula II wherein R is
a-amino-a-(p-hydroxyphenyl)acetyl~ a-amino-a-(3-chloro-4-
hydroxyphenyl)acetyl, a-amino-a-(3,5-dichloro-4-hv~roxyphenyl)-
~cetyl, a-amino-Q-~2-thienyl)acet~l, a-~mino--(3-thienyl~-
~cetyl, a-amino-a-(l-cyclohexenyl)ace~y~, a~amino-~-
(1,4-cyclohexadienyl)acetyl, a-hydroxyacetyl, ~-hydroxy-
a-(2-thienyl~acetyl, a-hydroxy-a-(3-thienyl)acetyl,
a-hydroxy-a-(l-cyclohexenyl)acetyl or -hydroxy-~- I
(1,4-cyclohexadienyl)acetyl, or ~ pharmaceutically
~cceptable salt thereof.
A most preferred compound of formula II is the scid
in which R is phenoxyacetyl, or a pharmaceutically
scceptable salt thereof.
knother most preferred compound of ormuls II is the
ac$d in which R is pheny1acetyl, or a pharmaceutically
scceptsble sfllt thereof.
A still furthe~ most preferred compound of formula II
is the acid in which R is a-aminophenylacetyl, or a
-32-
1--
25Z
:,
pharmaceutically acceptable salt thereof. The isomer of this
compound in which the~-carbon atom of the 7-acyl group is of
~-~ the D-series is of particular importance due to its combination
of good antibacterial activity and oral absorption.
A most preferred series of compounds of the present inven-
tion are the 0-2-isocephem compounds having the general formula
R-NH ~
IIId ~ CH3
~ wherein R represents an acyl group, and easily cleavable esters
- ~ and pharmaceutically acceptable salts thereof.
Preferred acids~ esters and salts of formula IIId are
~ those in which acyl group R is selected from the acyl groups
,. ,
- ~ defined above under (i) to (xvi). The acyl groups mentioned as
being preferred groups within categories li) to (xvi) are also
preferred in the compounds defined by general formula IIId.
More preferred acids, esters and salts of formula IIId
are those in which acyl group R is
Ar'-CH-CO-
~ in which Ar' is a radical of the formula
' .
Rm
in which Rm, Rn and R are alike or different and each is hydro-
gen, hydroxy, (lower)alkyl, cyano, (lower)alkoxy, chloro,
bromo, iodo, fluoro, trifluoromethyl, nitro, amino, (lower)alky-
lamino, di(lower)alkylamino, (lower)alkanoyl, (lower)alkanoyloxy,
- 33 -
.. I
~3L1~5Z
e.g. acetoxy, or phenyl and Y is amino or a group obtained by
reacting the amino group with acetaldehyde, formaldehyde or
acetone; fluoro; chloro; bromo; iodo; hydroxy; (lower)alkanoy-
' ' d loxy; carboxy; guanidino; 3-guanyl-l-ureido; 3-(2-furoyl)-
.~
ureido; 3-benzoylureido; sulfo; sulfoamino; ureido; thioureido;
(lower)alkoxy; cyano, cyanamino; or indanyloxycarbonyl.
Other preferred acids, esters and salts of formula IIId
~ I
are those in which R is
Ar'-CH-CO-
.,..... 10 Y
wherein Ar' is phenyl, p-hydroxyphenyl, 4-hydroxy-3,5-
dichiorophenyl, 3-chloro-4-hydroxyphenyl, o-, m- or p-
~ ~ aminomethylphenyl, 2-thienyl, 3-thienyl, l-cyclohexenyl or
`` ~ 1,4-cyclohexadienyl and Y is amino, carboxy or hydroxy.
,, ~
,.',
,.'
- 34 -
,
, .. . , _ . . _ _ . , . . . , . , . . . . _ . . .. ... . .. ... .... ~ . . . . . ., . _ _ .
~llg)Z5Z
Other . preferred compound~ of formula IIId are thoaa
~h~re$n R i8 an acyl group of the formula
~9H-CO- HO~CH-Cû-
NH2 NH2
Cl Cl
HO ~CH-CO-
HO~ CH-CO-
`~ C1 ~2
~,,!L CH-CO-; I~Ni~2
NH2
~CH-CO- , ~-CH-CO- J
NH2
1H ~S~L CH-CO-
OH
I~OH ~ ~H-CO-
1H
~CH-CO- ~H-CO-
COOH
-3s-
ZSZ
.-
:` . - ' ,
~ ~ca-co- ICN-CO-
. COOH
h'-CO- ~ H-CO - or
COO}~
CIH-CO-
~ :~. O
,,,., ~ . . .
. ~
. Other preferred compounds of formula IIId are
~ ! '
those whereLn R is an acyl group of the formula
. OCH3
- N_ C-CH2CO- , ~ CO-
CR3
. N - N
. ~ -CH CO- ~
I / 2 ~ ~ CH2-CO-
U'
:~ ~C~
.
25Z
wherein U and V are alike or different and e~ch is
- hyd~ogen, chloro or fluoro;
~ CH2CO- ~ 3 ~ H2CO-
.
~H2Co- ~~ CH2Ct)-
, .
~ OCH2CO- . ~SCHzCO- '
CH2NH2
~H2CO- , Cl-C7 alkyl-CO-
~CO- , ~CH2CO-
OC2H5
CH2C-
CO_ , N~N
--37--
}Z52
.
C1-C7 alkoxy-CO~ CO-
,,, , NH2
., .
'~ ~CH2C-NH-CH2CO-,
NH ~=~OCH2NHCO-
... . .
/N~ .
C-CH2CO- ,
N~ /
: H
''~'' ' '' ' ' '~3 ' . 0~,
` O--C C--H ~\
" I ~ CH2CO-
~ CH2CO-
: . N
.... .
;~ .
COOH C6H5
~0- , ~ CO- ~
.
.
~C~ ' ~ CH-CO- or
~ ' ,, N~ ,
:' C~12~H2 O'=C ~ C= O
~SC~12CO- C6}1s
-38-
~ 252
I
A m~st prefe.red group of eo~.pounds are those
acids defined by Lormulae IIId wherein 2 is a-carboxy-
phe~ylace~yl, cyano~cetyl, c-amino-~-(p-hydroxyphenyl)-
acetyl, a-smino-a-t3-chloro-4-hydroxyphenyl)acetyl,
a-a~ino-c-~3,5-dichloro-4-hydroxyphenyl)acetyl, c-
amino-a-(2-thlenyl)acetyl, a-amino-a- (3-th~enyl~ace~yl,
a-s~ino-a-(}-cyclohexenyI)ace~yl~ a-amino-a-(1,4-cyclo-
nexadienyl)acetyl, a-hydroxyacetyl, c-hydroxy-~-
t2-thier.yl)ace~yl, a-hydroxy-a-(3-thienyl)acetyl,
a-hydroxy-~ cyclohexenyl)acetyl, a-hydr~xy-c-~154-
cycloheY.adienyl)acetyl, c-~2rboxy~s-~2-thienyl)acetyl,
a-carbo~y-s-(~-t~ienyl)acetyl, a-car~oxy-a-(l-cyclo-
hexe~yl)acetyl, a-carbox~-_a-~i,4-cyclohexadienyl~-
scetyl, a-~ndanyloxycarbonyl-a-phenylacetyl, l~
,~
tetr2z~1yl, 4-pyridyl-hioacetyl~ 2-thiPnylacetyl,
3-thienylacetyl, l-cyclohexenylace~yl, 1,4-cyc~o-
hexadienylacetyl, o-amino~ethylphenylacetyl, l-amino-
cyclohexylcarbonyl, 2,6-dimethoxybenzoyl, sydnon2-
ace~yl or a-azidophenylacetyl, ~r a pharmaceutically
acceptabl~ salt thereor. The most preferred easily
cleavable e~ters of this group are the pivaloyiox,~methyl,
methoxymethyl, indanyl, phthalidyl and acetoxymetnyl esters
2nd pharmaceutically accaptable =al;s therecf.
-39-
zsz
:
:~ .
Another most preferred ~roup of compounds are the
D-isomers of those acids defined by formula IIId wherein
R is a-amino-a-~p-hydroxyphenyl)acetyl, a-amino-a-(3-
chloro-4-hydroxyphenyl)acetyl, Q-amino-a-(3,5-dichloro-
4-hydroxyphenyl)acetyl, a-amino-a-(Z-thienyl)acetyl,
a-amino-a-(3-thienyl)acetyl, a-amino-a-(l-cyclohexenyl)-
cetyl, a-amino-a-(1,4-cyclohexa~ienyl)acetyl, -hydroxy-
acetyl, a-hydroxy-a-(2-thienyl)acetyl~ a-hydroxy-a-
(3-thienyl~acetyl, ~-hydroxy-a-(l-cyclohexenyl)acetyl
or a-hydroxy-a-(1,4-cyclohexadienyl)acetyl, or a pharma-
ceutically acceptable salt thereof~ The most preferred
easi;ly cleavable esters of this group are the pivaloy-
loxymethyl, methoxymethyl, indanyl, phthalidyl and ac_toxy-
methyl esters and pharmace~tically acceptable Qalts thereof.
'i ,
A most preferred acid of formula IIId is that in
which R is phenoxyacetyl, or a pharmaceutically acceptable
8alt thereof.
A most preferred acid of formula IIId is that in
which R is phenylacetyl, or a pharmacuetically acceptable
salt thereo~.
A most preferred acid of form~la IIId is that in
which R is ~-aminopheny~acetyl, or ~ pharmaceutically
~cceptable salt thereof.
-40-
Z5Z
A most preferred compound of formula IIId is
the pivaloyloxymethyl, acetoxymethyl, indanyl, phthalidyl
.~ or methoxymethyl ester of the acid in which R is a-amino-
phenylacetyl, or a pharmaceutically acceptable salt there-
of.
A still more preferred compound of formula IIId
is the D-isomer of an acid of formula IIId in which R is
a-aminophenylacetyl, or a pharmaceutically acceptable
salt thereof. This compound is found to be especially
valuable in view of its combination of good antibacterial
~- activity and oral absorption. The pivaloyloxymethyl,
acetoxymethyl, indanyl, phthalidyl and methoxymethyl
esters of the above acid as well as pharmaceutically
acceptable salts thereof are also preferred compounds
~,r of the present invention.
The present invention further provides various
. novel intermediates useful in the synthesis of the
...~i
~ pharmacologically active 0-2-isocephern antibacterial
- agents described above.
Preferred embodiments of the present invention
are the novel intermediates having the formula
H H
N3 _ _
,:, ' ~ ~-1
:.~ O \~W'
C2R"
'``' V
¦ wherein W' is hydrogen, (lower)alkyl or aralkyl and R"
¦ 30 is hydrogen or an easily cleavable ester carboxyl-
; ~ protecting group, and salts thereof.
Especially valuable are the compounds of formula
- 41 -
~ l,
ZSZ
:
wherein W' is hydrogen, methyl, benzyl or phenethyl.
; The mos-t preferred intermediates of formula V
are those in which W~ is methyl.
Other preferred intermediates are the compounds
~- having the formula
N
'~ o~l\~\w~ '
. 10 C02R"
~ VII
,~
wherein W' is hydrogen, (lower)alkyl, e.g. methyl, or
aralkyl, e.g. benzyl or phenethyl, and R" is hydrogen
or an easily cleavable ester carboxyl-protecting group,
and salts thereof. The most preferred intermediates of
formula VII are those in which W' is methyl.
.~,,
-;~` The intermediates of formulae V to VII may be
,:~
~ in the form of the free carboxylic acid or a salt thereof
,{,
.~ or in the form where the carboxyl group is protected
-i 20 in a conventional manner such as preferably by ester-
ificatioh. The protecting group is selected so that
it may be removed by methods which do not result in
any appreciable destruction of the remaining portion
of the molecule. Preferred carboxyl protecting sroups
are the easily cleavable esters as defined above including
in particular benzhydryl, p-nitrobenzyl, trichloroethyl,
silyl including especially trimethylsilyl, phenacyl, p-
methoxybenzyl, acetonyl, ~lower)alkyl such as methyl,
t-butyl or ethyl, benzyl, triphenylmethyl, phthalidyl,
indanyl, methoxymethyl, acetoxymethyl and pivaloyloxy-
methyl. The most preferred esters of formulae V to VII
are the pivaloyloxymethyl, methoxymethyl, phthalidyl,
- 42 -
Z52
indanyl and acetoxymethyl esters, and salts thereof. The carboxyl
protect;ng group may be split off when desired by methods known
~, per se, e.g. by mild acid or base hydrolysis, catalytic hydro-
.~
genation, irradiation with ultraviolet light, or reduction with
chemical reducing agents. It will be appreciated that esterifica-
tion is only a preferred method for blocking the carboxyl group
`~ and that other carboxyl-protected forms of the above intermediates
e.g. easily cleavable amides or anhydrides~ are also intended to
be included within the scope of the invention.
According to the present invention there is also pro-
~ided a process for preparing 0-2-isocephem compounds of the
:;;
general formula H H
R-N
`- ~b
,'J~ O2H
wherein R represent: an acyl gro~p and 9 is hydrogen, ~lower)-
-~ alkyl or aralkyl, and easily cleavable esters and pharmaceutically
acceptable salts thereof, which process comprises N-acylating a
7-amino 0-2-isocephem intermediate of the formula
H H
I ~2
- N
,
VII CO2R"
, .
wherein Q is as defined above and R" is hydrogen, or an easily
cleavable ester carboxyl-protecting group R', or a salt thereof,
with an acylating acid of the formula
R-COOH
- 43 -
.. _ .. . .. . . . .. .. . .
~llg)ZSZ
-, -
wherein R is as defined above, or with its functional equivalent
as an acylating agent for a primary amine, to produce a 7-
. acylamido 0-2-isocephem-4-carboxylic acid derivative of the
:, .
formula
wherein Q, R and R" are as defined above, or a pharmaceutically
acceptable salt thereof and, if desired, performing one or
more of the additional steps of
~ 1) removing by methods known ~ se the carboxyl-protect-
ing group R' to produce the corresponding free acid compound of
formula II;
.. . ...
(2) converting the free acid compound of formula II to a
: ~ physiologically hydrolysed ester thereof by methods known
~ se; or
~ ~3) converting the free acid compound of formula II or a
physiologically hydrolyzed ester thereo~ to a pharmaceutically
acceptable salt thereof by methods known per se.
... The 7-acylamido 0-2-isocephem compounds of formula II are
-- prepared by N-acylation according to known methods of the 7-
. amino group of intermediate VII with an acylating acid of the
formula
R-COOH " .~
wherein R is an acyl group, or with its functional equivalent
as an acylating agent for a primary amino group.
The acylating agents for preparing the
~44-
~l~QZSZ
jl
; products of formula II are known, readily preparable
. by known methods or described herein.
~ . Intermediate VII may be acylated either
,.0 in the form of the free carboxylic acid (or
sslt thereof) or as an easily cleavable ester (or acid
addition salt thereof~. The procedures for preparing
esters of carboxylic acids are disclosed in the litera-
ture and are well-known to those skilled in the art of
penicillin and cephalosporin chemistry. Methods for
~;- lo preparing certain of the more preferred easily cleavable
esters, i.e. the pivaloyloxymethyl, acetoxymethyl,
methoxymethyl, acetonyl and phenacyl esters, are disrlosed
;~ in U.S. Patent 3,284,451 and in U.K. Patent 1,229,453.
~; . .
,............. The free acid form of intermediate VII may also be converte~ to
~ a 8ilyl ester, e.g. trimethyls~lyl ester, as Dy the
,,,~,,1;
~ methods described in the literature, e.g. U.S. Patent
, , ~
~ 3,249,622. The silyl ester carboxyl-protecting group
,. . .
- m~y be easily removed following the acylation reaction
by hydrolysis or alcoholysis.
~rior to tke acylat~on reaction, any reactive
~u~stituents on the acylating acid or der~vative
thereof, e.g. hydroxy, carboxyl or mercapto, m~y be
protected by use of suitable protecting or bloc~ing
groups which are well-kn~wn to those skilled in the
- 45 -
.... . . . ... . . . . . . .. .. . ..
lZ5Z
;
,--
art of ~-lactam chemistry, e.g. a8 by acyl2tion or
silylation. When the acyLating agent contains an
8~ino functional group in the scyl mo~ety, the amino
gro~p i8 protected by a convent~onal amino-blocki~g
group which may be readily reQoved at the conclusion
of the reaction. Exa~ples of sultable amino-protecting
or blocking grcups include t-butoxycarbonyl, car~o-
` ~ - benzyloxy, 2-~yd-oxy-1-naphthcarbonyl, trichloroethoxy-
.. ,
carbonyl, 2-ethoxycarbonyl-l-methylvinyl and 2-methoxy-
carbonyl-l-methylvinyl. A par~icularly valuable
blocking g-oup i5 a proton, as in the acylating agent
. ,.,~
of the formula
C-Cl
~2.~c~
P~eferred amino-protecting groups are ~-butoxycarbonyl,
;~ carbobenzyloxy, ;he p-oton and a ~-diketone or
,. ..,
= ~-kPtoes.er as ~n U.K. Patent 1,123,333 or U.S Patents
~,325,479 ~n~ 3,316,247, e.g. methyl ace~oacetate,
or a B-ketoamide as in Japan 71t24714. ~hen the
t-~utoY.ycarbonyl, carbobenzyloxy, B-~etoe~ter, ~-dik~-
tone or B-~etcamide protecting g~oups 2re e~ployed,
$t ~s prefe-red to convert the acyl~ing ac~d
c~ntaining th~ blocked ~ino group to a mixed anhydride,
e.g. with et~.yl or isobutyl chloroform~te, before
..........
. ~ ZSZ
. ~
.~ reaction with compound VII or an ester or salt
thereof. After the acylation coupling reaction,
the amino-protecting group and any other protecting
group used may be removed by methods known per se to
form the de3ired product o~ formula Il. Thus, ~or
e~ample, with respect to amino-protecting groups, the
t-~utcxycarbonyl group may be removed by use of
,"~
. ............. fcrm$c acid, the car~obenzyloxy group by catalyt~ c
hydrogenation, the Z-hydroxy-l-naphthcarbonyl group
.. , ~
by acid nydrolysis, the trichloroethoxycarbonyl group
by treatment with zinc dust in glacial acetic acid,
the proton by neutralizatlon, etc.
Acylation of a free amino group of a cephalosporin
or pen$cillin nucleus is a well-~nown reaction, and any
of the funtional e~uivalents of the carboxylic acid
RCOOH commonly used in penicillin or cephalosporin
chemistry as acylating agents foz primary amino groups
m~y be employed in acy~ating intermediate VI.
Examples of suitable acylaeing derivatives of ~he free
acid include the corresponding acid anhydr-des, mixed
anhydrides, e.g. alkoxyformic anhydrides, acid halides,
acid ~zides, acti~e esters and active thioesters. The
f~ee acid m~y ~e coupled with c~mpound VI
a~ter first reacting said f~ee 2cid with N,N'-dimethyl-
chloroformininium chlo.ide tc~. Great Britain 1,008,170
- 47 -
Z5Z
snd Novak and Weichet, Experientia XXI, 6,
360(1965)] or by the use of enzymes or of an
N,N'-carbonyldiimidazole or 2n N,~'-carbonyl-
d~triazole [cf. South African Specification
~3/2684J or ~ carbodiimide reagent ~especially N,N'-
dicyclohexylcarbodiim~de, N,N'-diisopropylcarbodiimide
or N-cyclohexyl-N'-(2-morpholinoethyl)carbodiimide:
cf. Sheehan and Hess, J.A.C.S., 77, 1967 ~1955)~, or
of slkylylamine reagent ~cf. R. Buijle and H, G.
Viehe, Angew. Chem International Edition, 3, 582,
(1~64)~ or of an isoxasolium salt reagent [cf. R~ B.
g Woodward, R. A. Olofson and H. Mayer, J. Amer. Chem.
~.
~; Soc., 83, 1010 (1961)], or~of a ketenimine reagent
-
~ t~ [cf. C. L. seevens and M.~E. Munk, J. Amer. Chem. Soc.,
i
~- 80, 40~5 (1958)] or of hexachlorocyclotriphospha-
: trisz~ne or hexabr~mocyclotriphosphatri~zine tu.s.
3,651,050) or of diphenylphosphoryl azide ~DPPA;
J, Amer. Chem. Soc., 94, 6203-6205 (1~72)~ or of
diethylphosphoryl cyanide [DEPC; Tetrahedron Letters
No. 18, pp. 1595-1598 (1973)] or of diphenyl phosphite
~etrahedron Letters No, 4~, pp. 5047-5Q50 (1972)].
¦ Another equivalent of the acid chloride i5 a corres-
ponding azolide, i.e., an amide of the corresponding
acid whose amide nitrogen i5 a member of a quasi-
~r~mst~c five me~bered ring containing ~t lesst two
,
-48-
~ Z5Z
.
ri~
.
- nitrogen atcms, i.e., imidazole, pyrazole, the
. .,
triazo}es, benzimidazole, benzotriazole znd their
u~st~tuted der~vatives. As an example of the
~ ...
general meehod for the preparation of an azolide,
; ~ ~,N'-carbonyldi~midazole is reacted with a carboxylic
... .
acit in e~uimolar proportions at room temperature in
tetrshydrofuran, chloroform, dimethylform2mite or a
similar inert solvent to fo~m the carboxyl,c acid
imitazolide in practicaLly ~uantitative yield with
liberation of carbon dioxide and one mole of imidazole.
~icarboxyl~c acids yield dimidazolide. The by-product,
imidazole, precipitates and may be separated and the
imidazolide isolated, but thiâ ~s not essential. A
preferred acylating agent for preparing 7-acyla~ido
ccmpounds containing an a-~mino substitnent, e.g.
c-am~nophenyl, a-amino-a-thienyl, etc. is the N-
carboxy anhydride tLeucn's anhydride~. In this
structure the group which activates the carboxyl
group also serves to protect the amino group.
Another preferred acylating agent for introducing
a ~ide chain containing an c-amino functional group
i8 the acid chloride hydrochlor~de, of the for.~ula
~.
Ar-CH-COCl
NH2 HCl
.'
--~1 9--
2S2
.~.
-~,
, which also sesves a dual function of carboxyl acti-
- vation and amino protection. Mention was made above '
~ of the use of enzymes to couple tbe free acid with
; ~ comp~und VII. Included i~ the scope of
,.,~..
such processec sre the use of an ester, e.g. the
methyl ester, of that free acid with enzymes provided
by ~arious microorganism , e.g. those described by
T. Takahashi ee al., J.A.C.S " 94(11), 4035-~037 (1972)
Bnt by T. Nara et al., J. Antibiotics (Japan) 24(5),
321-323 (1971) and in U.S. 3,682,777. A particu}arly
preferred coupling agent for coupling the acylating
.
~ acid with compound vII (or a salt or ester
.~
thereof) i~ N-ethoxycarbonyl-2-ethoxy-1,2-dihydro-
quir.oline (EEDQ) as described ~n J.A.C.S., 90, 823-824
. ~ ,
- ~ and 1652-1653 (1968) and U.S. Patent 3,455,929.
The particular process conditions, e.g. temper-
, sture, solvent, resction time, etc. selected for the
3~
coupling reaction sre determined by the naeure of
the reactants and acylation method used and are known
to those s~illed in the art.
The scylsting agents which may be used to form
the N-acyl active c~mpounds of formula II
sse known in the literature along with methods for
theis 8ynthe~is. }n those cases where the acylating
'
- 50 -
' ''
~ Z52
~gent cone~ins one or more 2sy~etric carbon atG~s and
thus exists in optically 2ctive form~, the c~pound~
obtained using such an acylating sgent are ordins.i1y
obtained in racemic form. When the sepsrate optical
$som2rs are desired, ehe acylating agent can be
.0 ~ ~ , .
:esolved in a conventional ~anner such as by reacting
the free acid with cinchonine, strychnine, bruci~e or
. th2 like, fractionally crystallizing to sepa~te the
~isstereoisomeric salts and separately acidi~ying the
801~ d phase ~nd the liquit pha~P to liberate the
. opt$cal isomers.
The compounds of ehe present invention m2y be
. ~olated in any of the ways customarily em~loyed for
~..
the isolation of corresponding cephalosporin csmpounds.
Formation of the desired pharmaceutically acceptable
csrboxy~c acid or acid addition salt is car~ied out
by known methods, e.g. reaction of the acid (or ester
in the case of acld addition salts) with an ~ppropriate
bas~ or acid.
At the conclusion of the acylation reaction, the
product obtained may be converted (before or after
remDval of any protecting groups3 by method3 known
se to another desired product of formula II.
Thus, the compound of formula II
,1 .
,, .. , .. .. , .. , -- .. . .... .. . .. .. .. . . . . . . . .. . .
:
: ~ Z5Z
in the form o~ the free acid or a salt thereof may
be converted by kno~n methods to t~e corresponding
physiologlcally hydrolyzed ester or pharmaceutically
acceptable salt thereof. Similarly, the product
of formula II ln the form of an easily
cleavable ester or salt thereof may be converted to
the free acid product or pharmaceutically acceptable
~ - salt thereof by removal of the esterifying group, e.g.
_~ by aqueous or enzymatic hydrolysis (as with human or
animal serum) or acidic or alkaline hydrolysis or by
catalytic hydrogenation or by treatment with sodium
thiophenoxide as taught in U.S. Patent 3,284,451.
The easily cleavable esters of the compounds
;~ of formula II are useful as intermediates in the
production of the free acid product. The pivaloyloxymethyl,
acetoxymethyl, phthalidyl, indanyl and methoxymethyl esters
are also useful as active antibacterial agents since on
oral administration they are rapidly hydrolyzed to the
active metabolite. These esters are of particular interest
because they provide on oral administration different rates
. -k' and amounts of absorption and give differing concentrations
of the active antibacterial agent in blood and tissues.
.
-
- 52 -
~ 25Z
: '-
., ~
,,
,. In still another aspect of the present 'n~ention,
.~ these ~s provided a process for the prepar~tion of sn
: ~ -0-2-isocephem-3-carboxymethylene derivative of the
,-..
formula
~\ ~
CH2CO~Z
~ ~ Oz~ .
.
IV
r whcre~n P~ repre~ents an acyl group and Z i9 hydrogen or
~, the residue or an ester gro~p and essily clea~able estersand pharmaceutically accepta~le sal~s thereof; which
" .;~
process comprises
(1) reacting an Q-2-isocephem co~pound of the
U ~
'................................. co2R
IIIb
. - wherPin R represents an acyl group and R' is an easily
clea~able ester car~oxyl-prote~ting group with carbon
dloxide in the presence of a base in an inert organic
',-
. ~ ~ solvent at a tem?er~ture in th~ range of about 0C. to
: .
-53-
!
.. . .... . . . .. . . .. . . . . . . . . . . . ..
Z
. -80C. to produce upo~ acidirication the c~mpound of
., .
~ the formula
,~ . ~ ~
.,
. r- ~
;. , o~N ~C~2C02H
XX~I C02R '
wherein R and R' are as defined abcve, or 2 phar;n2-
ceutically acceptable salt thereo~ and optionally
performing on~ o~ more of the addi~iona~ steps of
, ts) remoYing by methods known per se
. the protect~ng group R' to produce the
corresponding 4 -carboxyl~ c acid compo~nd
c ~ of formula XXII;
'`'~5 . ~b) converting ~he 4-carbaxylic acid
. ~ compound of ~or;nula ~ II to a physiologically
hy~ro-lyzed ester thereof by methods known per
. se; or
.:,
- (c) converting ~y metnods ~cnown pe~ se
t~2e 4-carbox~lic ac~ d com~auhd of crrr.~ia
XXII or a physiologically ~ydrolyzed ester
thereo~ to a pharm~ceutically accepta~le
salt thereof; and, when it is desired to produce
a c~mpound of fcrmula IV where Z ~ s the residue oE
an ester grou~, .
(2) est~rifying the f~ee carbo~yl ~roup 2t the 3-pos~-
ticn of co~npound XXII by r~ethods known pe~ se to produce
-54-
, . . . .. ... . . .. . . .... . .. . . . .. .. . ..
. _ , _ ~
:~ ` ~ L~IZ5Z
o~
~,.
~1 a compound of the formula
j~ R-I~H2COOZ
IVa C02R'
: wherein Z ls the residue of an ester group and R and R'
ar-e as defined above, or 3 pharmaceutically acceptable
salt thereof and, if deæired, performing one or more of
t~e additional steps of
(d) ~electively removing by methods known
. Der se the protecting ~roup R' to pr~duce the
desired 4-carboxylic-acid compound of formula
3 IV wherein Z is the residue of an ester group;
~ l ~ (e) converting the 4-carboxylic acid
: ~ ~ cc~ound of step (d) to s physiologic211y
hydrolyzed ester thereof by methods known
: - ~er se; or
: . tf) con~erting by methods known per
: se the 4-carboxylic acid compound or step
: - (d) or a physiologically hydrolyzed ester
thereof to a pharmaceutically acc~pta~le
sslt thereof~ -
',", '~''
'
-55-
1 - -
~ 252
~-~
-'~r Acyl group R in starting material IIIb may be any
`~ organic acyl radical but is preferably selected from
those acyl groups described above as preferred in connec-
tion with the compounds of general formula I. Carboxyl-
protecting group R' may be any easily cleavable ester
~ group conveniently used to block a free carboxylic acid
-~ functional group. The term "easily cleavable" has the
~- same meaning as described previously, i.e. removable by
,~
- methods which do not result in any appreciable destruction
of the remaining portion of the molecule. Preferred
.~ protecting groups are benzhydryl, benzyl, p-nitrobenzyl,
trichloroethyl, silyl including ~specialiy trimethylsilyl,
phenacyl, p-methoxybenzyl, acetonyl, (lower~alkyl including
particularly methyl, ethyl and t-butyl, triphenylmethyl,
. I
methoxymethyl, acetoxymethyl, phthalidyl, indanyl and
pivaloyloxymethyl.
The carboxylation reaction is carried out by reacting
~; the carboxyl-protected compound Ib with gaseous carbon
dioxide in the presence of a base. Suitable bases for
this step include sodium hydride, n-butyl lithium, t-butyl
lithium, lithium dicyclohexylamine, lithium 2,2,5,6-tetra-
, ,
, methylpiperidine and lithium diisopropylamine. The pre-
ferred bases are n-butyl lithium and t-butyl lithium.
The ester IIIB is dissolved in a dry inert organic solvent,
; e.g. tetrahydrofuran, and dry gaseous CO2 introduced into
: '
56 -
,
25Z
.~.
the mixture of base and IIIb solution. The reaction
mixture is cooled before introduction of the CO2 to
a temperature in the range of 0C. to -80C. and then
allowed to warm to room temperature with continued
addition of carbon dioxide. Upon acidification, e.g.
with a mineral acid such as aqueous ~Cl, compound XXII
may be recovered.
Upon cleavage of carboxyl-protecting group R' to
form a free 4-carboxyl group, e.g. by hydrolysis,
chemical reduction or catalytic hydrogenation, the
3-carboxymethyl acids prepared by the carboxylation
step or physiologically hydrolyzed esters or pharma-
ceutically acceptable salts of said acids or esters may
be used as active antibacterial agents.
Compound XXII may also be esterified by known methods
to form the desired carboxyl-protected compound of formula
IVa where Z is the residue of an ester group, most
preferably Cl-C6 alkyl, e.g. methyl, ethyl, n-propyl,
- isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl,n-heptyl, etc. The ester group Z should be one which is
~ resistant to conditions required for removal of blocking
;~ group R', e.g. resistant to hydrogenolysis. The most
preferred ester, the methyl ester, may be prepared for
example by reaction of compound XXII with diazomethane.
The preferred lower alkyl esters may also be formed by
use of the mixed anhydride reaction or by the use of
:
- 57 -
;
252 --)
dimethylformamide acetal~ ~s described ~n Helv. Chim.
Acta., 4a ~ 1746 (1965). Upcn selective cleavage of
~locking grcup R' by known methods~ e.g. acid labile
blocking grour~ such as t-butyl~ p-methoxybenzyl or
.
tetrshydropyr~nyl m2y ~e selecti~ely removed by ~ild
:3
, acid treatment and groups such as ben~yl or p-n~trobenzy
may be selectively rem~ed by hydrogenolysis, the inter-
¦ mediates of formula IVa ~here R' is not physiologicall;
hydrolyzed may be converted,to 4-carbaxylic acid acti~e
~, ~ ~ntibacterial sgents. The free acid products may option-
: :-..;.,
, ally be convertPd according to known mPthods to pnysiolog-
~, ~cally hydrolyzed esters or pharmaceuticslly scceptsble
s~lts ~hereof.
. ~ ~
. ~ ,;
,, T~e compounds and phsrmaceutically acceptable sal~s
-~ of form~as XXII wherein R' is a physio~ogically hydrolyzed
est OE group or the de-blocked compounds of formula XXIT
i.
~ or physiologically hydrolyzed esters or pharmaceutically
;~."
acceptable salts of said ac~ds or es~ers are as ~entioned
sbove active antlbacterial ager.ts. These compounds and
salts haYe approximate}y the 6ame d~gree of actiYity as
the ~cids, physiologically bydrolyzed es~ers and pharma-
ce~ically acceptabl~ salts of formul~ IV, but are more
diff~cult to isolate from the reaction mixtu~e because of
the presence of the free car~oxyl group on the 3-p~sition.
For th~s reason, the preferred co~p~unds and salts ¢f
formula IY are those ha~ing ~h~ es~r~fied c2-boxy~ethylene
3-s~bstitu2nt, most preferably tnoie r.aYing a Cl-C~ a'k-~l
~ad~sl f~r th~ ~ substitue~t.
,
. .
ill~Z5Z
,"~.,~
' `~
The pha~msaceutically active compo~nds of the
present invention sre potent antibacterial agents
u8eful in the treatment of infectious diseases in
poultry and animals, including man, caused by m~ny
Gram-positive and Gram-negative bacteria. The active
compounds are also of value as nutrieional supplements
in animal feeds and ~s agents for the treaemene of
mastitis in c2etle
The no~el medicaments pro~ided by the present
invention may be formulated as pharmaceutical composi-
tions comprising, in addition to the sctive ingredient,
8 pharmaceuticslly acceptable carrier or dilslent. The
compounds may be administered both orally and parenterally.
The pharmaceutical preparations may be in solid form such
ag cspsS~les~ tablets or drag2es, or in li~uid form such
a solut$ons, suspensions or emulsions. In the treatment
of baceerial infections in man, the active compounds of
this invention may be a~ministered pareneer211y or orally
in an a~ount of from about 5 to 200 mg/Kg./day and
prefersbly about 5 to 20 mg./Kg./day in divided dosage,
e.g. thTee or four times a day. They are adm~nistered
in dosage units containing, for example, 125, 250 or
500 mg. of active ingredient with suitable physiologi-
cally acceptable carrier~ or excipients.
,,,, ,, . , , .. .. , , , . . . _, " , . . _ , ,, _ .. , . , .. , . .. ., . . .. , . ,,, , . . .
,, . _ .. . .
: :
:
Another prefer-ed embodiment of 'he ?resent
-A.S invent on is the process of preparing 2 7-amino
~ 0-2-isccephem intermediate of ~he formula
.'~
~ H
" ' ' ' 1 J i _ =
.,, H2N
,' ,.-~
~ VII CO2R"
' '~
~,".',
, ~ wherein Q is hydrogen, (lower)alkyl or ~ralkyl
...,.~
and R~ is hydrogen or an easily cleavable ester
c~-~oxyl-protecting group, or a salt thereof; which
.. ~
process comprises selectively reducing a 7-azido
~ntermediate of the f`ormula
~ ~ = ~W
, '~
. wherein W is as defined above, R' is an easily cleavable
~; ester carboxyl-protect-ng group and, i desired, remo~ins
. protectinS group R' by methods known per se to produce the
. corresponding rree zcid inte~ediate of formul2 VII and, i-
.~
~Psired, converting the free acid form of intermediate
VII to ~ salt the~eof by methods kncwn Der se.
- 60 -
.. . . , ... . .. .. . . ~ . .
Another preferred embodiment of the prese~t i~vention
is the process of preparing a 7-azido 0-2-isocephem intermediate
of the formula
H H
N
Ll
V ~ N
C2R"
wherein W is hydrogen, (lower)alkyl or aralkyl and R" is hydro-
:. ~ 10
gen or an easily cleavable ester carboxyl-protecting group, or
a salt thereof; which process comprises cyclizing by treatment
` with base an enol intermediate of the formula
~ .
., , . ~.
'`
H H CH2OSO2-(lower)alkyl
N _ = / -
IX I =
wherein T is hydrogen or ethyl, W' is hydrogen, (lower)alkyl or
aralkyl and R' is an easily cleavable ester carboxyl-protecting
. ~.
group and, if desired, removing protecting group R' by methods
known per se to produce the corresponding free acid intermediate
. .
of formula V and, if desired, converting the free acid to a salt
thereof by methods known ~ se.
Preferred reducing agents for this step include chemical
reducing agents selected from zinc and ammonium choride in an
inert organic solvent, e.g. methanol, and hydrogen sulfide and
; triethylamine in an inert organic solvent, e.g. methylene
chloride. Catalytic hydrogenation may also be employed with
such selective hydrogenation catalysts as noble metals ~most
preferably palladium or platinum), noble metal oxides (most
. I
_61_
... . .. . .. .
ZSZ
preferably palladium oxide or platinum oxide), or Raney nickel,
said catalysts being optionally supported on a conventional
carrier such as carbon, dlatomaceous earth, etc. Preferred
solvents for catalytic hydrogenation are non-reducible inert
solvents such as methanol, ethanol and ethyl acetate. Hydro-
~'
genation is preferably conducted at xoom temperature and at
atmospheric or slightly elevated pressure. As in the case
of the 7-azido 0-2-isocephem intermediate discussed above,
compound VIIa may, if desired, be converted by methods known
per se to the corresponding free carboxylic acid form or
to a salt of either the esterified or free acid form. As an
,~i
alternative to the stepwise reduction of the azido group and
removal of the ester carboxyl-protecting group, it is also
possible by choice of proper reduction conditions and protect-
ing groups to simultaneously reduce the azido group and ester
protecting group. Thus if a mild hydrogenation catalyst
is used such as 10% Pd-on-charcoal or a mild chemical reducing
agent such as H2S and triethylamine, the azido group is
reduced to an amine but a benzyl protecting group is untouched.
If a more active catalyst, however, such as 30% Pd-on-
., ~ t'~
~i diatomaceous earth is employed, both azido and benzyl groups
.,~
are reduced.
Compound VII or an easily cleavable ester or saltthereof is of use primarily as an intermediate in preparing
the active N-acyl derivatives of formula II. Compound
VII upon conversion to the free carboxylic acid (or a
physiologically hydrolyzed ester or pharmaceutically accep-
table salt of said acid or ~ster) also possesses antibacterial
activity per se against Gram-positive and Gram-negative
bacteria.
3Z5Z
~: I
I Enol lntermediates IX which, depending on the
definition of T and W', are prepared by various
methods described below, are cyclized to the azido 0-2-
isocephem intermediate V by treatment with a base.
Examples of suitable bases for this step include an alkali
metal hydride, most preferably NaH, in a suitable organic
solvent, e.g. dimethylsulfoxide or dimethylformamide,
triethylamine in an inert organic solvent such as methylene
.
chloride, chloroform or (lower)alkanols, e.g. methanol or
, ~
ethanol and sodium or potasslum acetate in a suitable
solvent such as dimethylformamide. Generally it is
preferred to employ the azido 0-2-isocephem in its
carboxyl-protected form in preparing the active 0-2-
isocephem antibacterial agents of formula I. If
-i desired! however, the ester group of intermediate
V may be removed bv methods known pe_ se to produce
the free acid form of compound V. The ester or free
acid forms of the azido-isocephem intermediate may
also be optionally converted by known methods to
-, ~
~ ~ 20 salts thereof.
i
.'-r~:i
_
''' '
,. "
-63-
I
... . . . .. . . .. , ., - - -
A further preferred embod~ment of the present
-:.
'nvention i3 a proces~ for the pr~paration o an
enol intermediate of the formula
r. ~
;~ 3--C_c_~C~z~502C 3
'~ . ~X~
. wherein R' is sn easily cle~able ester carboxyl-
.,~
protecting group; which process comprises subjecting
to ac~d hydrolysis a methanesulfor.yl derivative of.
~,
. ~ the formula
.... ~
. . ,
N3 ~ ~ ~ CH20S02CH3
C--C
wherein R' i8 as defined abov~.
-,
A further preferred e~bodiment of the present
~nvent~on is a process for the preparation of an enol
intermedia.e of the formula
N~ _ / C~20S02CH3
o_ 1 l j ~ I ~w
_ Co2R
X
where~n W ls methyl, benzv1 or phenethyl and ~
an easily cleavable ester cz~bo~yl-p~o;ecting group;
.. .. .. ...
.......
Z52
. .
.Y~ ~h~ch process comp.ises subjecting to acid hydrolysis
a methanesulfonyl deriv2tive o~ the ~ormula
,.,
-~.,
, ,`'4.'. 'N3 H / CH20SO~CH3
'~ 0=l~ /C/W
-, .. ,~ , l
i' ' ~02R '
XXVII
. ,:
: wherein R' snd W 3re as defined above
.~ ~
~ ~herein R' i8 an easily cle~vable ester carboxyl-
:. -.
protecting group and W is as defined above, or a
8ale thereof ~nd, if de~ired, removing protecting group
, ~
- R~ by ~ethods kn~wn Der se to produce the corres-
: ~ ponding free acid ~n~ermediate of formul2 VIII and,
. ~ if des~red, conv~rting the free acid to a salt
~ thereof by methods known per s2.
; ~ ~ A variation of the above-described process ror pre-
~ parirg the 0-2-isocephem antibacterial agents of for~ula rI
: ~ when W is hydrogen, and easily cleavable esters and pha=ma-
ceutically acceptable sal,s thereof involves ~eacting the
. - ., .
alcohol o~ rormula XIII with a methanesul or.ating ager.~ in
. the presence of an acid acceptor to produce a methanesulfo~y
derivative of the formula
:- N3 ~ H ~ CH2oso2cx3
I ~ OCH2SH3
~ _ C ~ \ H ~C ~
i OCH2cH3
C2R '
III
I - 65 -
!
, . ,,, , , . , , ,,, ~ , . , . , , , ~ , . . . . . . . . . .
)Z5~ -)
wnerein R' is an eas,ly cl~avable es;er car~o~yl-
protec,ing grou?. Compound X~rIlI is then -eacted with
-. aceeic ~nhydride in the presence of zinc chloride,
trifluoroacet~c anhydride, tit2nium te rachloride,
. boron erif~uoride or stannous chloride to produce a
compound of the form~la
' '
^
. N3 ~H ~ CH20S02CH3
C
~2~'
.~ ~IX
~.
- wherein R' is as defined above. Compound XIX is then
. 8ub~ected to base hydrolysis to form an enolate of
. ~ the formula
' .~ .
-.-..~,~i
: ~ N3 H H,,~CH20S02CH3
~C~
,
~ XX C02Rr
_
wherein R' ~ 8 as defined above, Enolate XX is
cyclized with bzse to ~he 7-azido 0-2-isocephe~l
~ntermediate of formula Va which i9 subs~q~ntly
r2~uc~d, N-acyla~ed and op~iQna~'y de-blocked
acc~r~lng to the process described abo~e to
produce the desired co~.~ound of formula II, when r~
is hydroge~, or an eac-ly cleavable ester or pharma-
ceutically accep_a~le salt thereof.
-~6
, . . . . .
Z5z
A still further alternative process for preparing
compounds of formula II, when W is hydrogen, involves
reacting the compound of the formula
H H
~.,` -- _ CH20H
. N3 C C /
H OCH2CH3
O C - N ~ D C''
., C
. C2R
. XV
wherein R' is an easily cleavable ester carboxyl-
protecting group with a methanesulfonating agent
in the presence of an acid acceptor to produce a
'! methanesulfonyl derivative of the formula
:
- H H
; - - CH OSO CH
N - - ~ 2 2 3
3~ C C'' H
CH2 3
O - C - N ~ ~ C
;:: C
C2R '
XIX
wherein R' is as defined above. Compound XIX is
then treated with base to produce an enolate of formula
XX and then cyclized by treatment with base to the 7-
azido 0-2-isocephem intermediate Va which is reacted as
described above to produce the desired compound of
formula II, when W is hydrogen, or an easily cleavable
ester or pharmaceutically acceptable salt thereof.
- 67 -
~`~
252
. According to another aspect of the present invention,
~. there is provided a process for preparing a 7-amino 0-2-
. isocephem compound of the formula
,,
~ H2N -- H
,,' _ 0~}~N~\ 1
: VIIa CO2R'
wherein R' is hydrogen or an easily cleavable ester
. 10 carboxyl-protecting group, or a salt thereof;
j,
which process comprises the consecutive steps of
.
.~
-~, (1) reactiny an ester of the formula
., .
. . .
~ (CH3CH20) 2CH-CH-C02R'
,~ . I
~ , _ NH2
wherein R' is an easily cleavable ester carboxyl-
protecting group with cinnamaldehyde in an inert
~:~ organic solvent in the presence of a drying agent or
with azeotropic removal of water to produce an imine
. of the formula
'' I
H H-~ - C H
C C- H
N ¦ ~ OCH2CH3
\EC~ / OCH2CH3
:XII C2R'
; wherein R' is as defined above;
, -68-
.. . ... . . . .. . . .
252
:
~ .
~ (2) react'ng said imine o i~ormul~ XII ~i~h an
, ;
. azi~oacetyl hallde on ~n azido~cetlc mixed ar.. -.ydr~de i~
~ he presence of an o~ganlc b26e to produce a c~ s,-~-
.. ~.
, lactam compound o~ the ~or~nula
.. ~ H ~ l l C6X5
. ~ N3 - ~C-H
o=c 1 ~ I ~OC~2CH3
.. ~~ 2C~3
IV C~2R ~
~ .:
wherei~ R' i8 as define~i above;
, .
~3) subjecting said ~-lac~am compound of
. ~ formula IV ~3 ozonoly~is to p~oduce an ald~hyde
c~f the fo~mlla
~ ~.. ,-,;
- - / CHO
H ~OCH~CH3
., ~ / C)C~2CH3
:.~` C02R '
XVI~:I
wherein R ~ ~ ~ as defirted ab~e,
- 6 9--
. .
Z5Z
, .
.
.
:~
-~ (4) selec_~ely ~educi~g s2id ~l~ehyde or
:~ . f~r~Nla XVIII .o the corre~pondi~g alc~hol of th~
.~
. ,
-~ ,
:4
'.~ .
- - / C~2Q~
= C N ~ ~ \ oC~2C~3
~;~ . .~02R '
~. XIII
: wherein R' is as defined ~bove;
:
(~) reacting the alcoh~l of formula XIII
wlth 8n acld anh~dride ln the presence of a ~ewis
acid to produce a compound of ~he ~ormula
'''~.
~ ~-..
~3 ~ -- / C~20CO-An
. I C--C
,, ~ I ~C ~
1~2R t
;,.
~herein R~ i8 as defined abo~e and An repres~nts
~he .e~idue of the acid anhydrlde;
;
.. - 70 -
.... ... . . ... . .... ... ... . .. . ...
~ 25Z
,
,., ..,.,
~t~
~,x (6) sub~ ectlr~, t5.le co~pourld o~ 'ormula XIV
-~ eo acid hydrol~sis co produce a c~m?ou~ of ~h~
f~la
,,,
... ~ X3
~: . ~C -~CX20~
,; o I I ~ ~0~2C~3
; - ~;`.,,',~,',,.1,~ ~ C
C~2R l
wh~rei~ Rl i8 as def~ned above;
: (7~ reacting the compound c~f for~la XV
wit~ an am~ ne to prodllce a~ enami~e compound
~ ~ thP f~la
: ~ N3 ~C~2}~
'~ o= I~ X~t
. _ ~02R '
XVI
wherein B.' is a5 defined above and X" i8 the residue
o~ the amlne;
_7,_
1,
252
`:
~) re2ctin~ the er.a~e of for~ula XVI wi~h
: D
a ~lower)al~lsul~onat ng a~;ent in ~,he pre&eace o~ an
~:~ acid acceptor to produce 2 derlvatl~e
o~ the formula
:~ ~
.,
. 1~3 ~ ~Cd20S02 - (lower)a~l
~ ~ N-X "
;~ O= C - N~ ~,~:
- ~i ~02B.
XVII
- wherein R~ and X" are as deflned above;
~ (9) su~; ec~ing ~aid deri~atl~e
: ~ of ~ 1a XVII to acid hyd;:o~ysi~ to prsduce ar~ enol
~ ? ~ntermPdiate of the formula
' '-' '''IJ
E~3 H H/ C~20S02 - ( lower ) a lkyl
~ C C
; O_--~\ ~C
~t)2~
'' . ~X
~.,
wherei3 R' i~ as defined abo~e;
(lû) cyclizir~g said enol ~ermediate by
t~es~m~t wi~h bas2 ~ producR a~2 azido 0-2-isocephem
intermediate of the fonnula
.` --, 2--
. .
Z52
:
H H
` N ~ ~
O - C N ~
C02 R '
Va
wherein R' is as defined above;
(11) selectively reducing said azido inter-
mediate of formula Va to produce the compound of the
formula VII.
According to still another aspect of the present
invention, there is provided a process for preparing a
7-amino 0-2-isocephem compound of the formula
H H
`,,: H2N~ ~/\
,.,, rl l
''' O ~ W'
,.. , C02R"
: VIII
: wherein W' is methyl, benzyl or phenethyl and R" is
hydrogen or an easily cleavable ester carboxyl-
10protecting group, or a salt thereof; which process
comprises the consecutive steps of
(1) reacting a ketal amine of the formula
.
W - C - CH-COOR'
/\ I
.. .
XXII
.
wherein R' represents an easily cleavable ester
carboxyl-protecting group and W is as defined above
~ - 73 -
25;Z
,~ .
with cinnamaldehyde in an inert organic
solvent in the presence of a drying agent or with
azeotropic removal of water to produce an imine of the
formula
H H-C ~ 6H5
C CH ~
il o o
N ~ \ C
\I/ \W
C2R '
XXIII
wherein R' and W are as defined above;
(2) reacting said imine with an azidoacetyl halide
or an azidoacetic mixed anhydride in the presence of a base
to produce a cis-~-lactam compound of the formula
: H-C ~ 6 5
- H H CH
-- -- /
N3 C C ~
'. I I 0\ ~0
O - C N H C
--, \1/ \W
C2R '
XXIV
; 10 wherein R' and W are as defined above;
(3) subjecting said ~-lactam compound of formula
: XXIV to ozonolysis to produce an aldehyde of the formula
H -- / CHO
3 C C
0\ ~0
O - C _ N \ ¦ / W
XXV C2R'
. , .
- 74 -
~10252
wherein R' and W are as defined above;
(4~ selectively reducing the aldehyde of formula
. XXV to the corresponding alcohol of the formula
H H
- --/CH20H
N3IC C /~-\
O\ O
O= C N\ H/ C
C W
XXVI 12R'
~ wherein R~ and W are as defined above;
:. (5) reacting said alcohol with a (lower)alkylsulfon-
ating agent in the presence of an acid acceptor to produce
a derivative of the formula
:~ H H
: _ _ ~ CH20S02-(lower)alkyl
N~ C C
~ I I Or~O
- O--C N\H \C/
XXVII C2R'
wherein R' and W are as defined above;
(6) subjecting said derivative of formula XXVII
to acid hydrolysis to form an enol of the formula
H H
3~ ---C / CH20S02-(lower)alkyl
1 ¦ fH
05C N C
\C~ W
X
C2R '
wherein R' and W are as defined above;
- 75 -
~ 25 2
''
~' .
: ~ ~7) cyclizing the enol of ~ormula X by treatment
~' w~th base to produce an azido 0-2-isocep~em inter-
med~ ate of the fonr~ula
H H
N3~
v~; o~N ~J~w
.. , ~ ,
~tla ",02P~ T
~ " _ .
. ~. ~herein R' and W are a~ defined abo~e; and
.,.. ,~ ~
(8) 9elect~vely reducing the azido 0-2-isocephe~
~teL~ediate of formula VIa to produce a 7-a~nino 0-2-
.~
ocephe~e = ~e ~ormula
N ~ W
~ _ ~ o R'
,, . ,
~ ~ ~herei~ Rl and ~ are as def~ned above.
.,.
: '
: -76-
;Z5 2
.1 .
.~..
~ he ester 6tartLng material of for~ula XI may be
..
prepared by the general method as illustrated in more
detail ~n the disclasure and examples ~elow for the
case in which R' is ethyl. The ethyl ester of formula
XI m~y be prepared by the foll~wing reaction se~uenc~:
~'
` NaOEt
~F~ , HC02Et ~ 1 ~2-C02Et ~ooc
'' NHC}iO'
- dry HCl (g)
~ NaOCH : C-~02Et ~-0C.
~ NHCHO EtOH
,'.~. CH2C12
.., .
.'........... , NaHco3
~ (EtO)2CH-C`H-C02Et or >
N~2~HCl .
. - .~ .. ~ij
~EtO)2CH-CH-C02Et
,~ . NH2
~; By replacing the ethyl glycinste in the above process
~ith other desired eas~ly cleavable esters, searting
~aterials hav~ng other 6U~ table car~oxyl-protecting
,.
groups may be prepared.
Conversion of ester XI to the Schirf base XII
may be effected by condensing the ester with cinnamal-
dehyde in an inert organic soivent preferably with
heating and most preferably at reflux temperatures.
The condensation reaction is carried out ln a suitable
inert organic solvent, e.g. benz2ne, ether or ~ethylene
chloride, in the presence of a drying agene~ e~.g,
- -77-
.. . ... ., ^
. ~ 252
.,
Na2S04, MgS04, molecular sieves, etc., or, alter-
natively, by removing water azeotropically as with
benzene.
~ :.
~ The imine of formula XII is then condensed with
: ~ an azidoacetyl halide, e.g. chloride, in the presence of
....
an organic base, preferably a tertiary amine such as
'a trialkylamine, e.g. triethylamine, or pyridine. The
r,',~
reaction may be conducted in an inert organic solvent
. which may advantageously be a hydrocarbon or halo-
genated hydrocarbon solvent. A most preferred
'i ~ solvent for this step is methylene chloride. Best
results are obtained when the reaction mixture is
cooled to about 0-5C. At the conclusion of the
reaction, the Schiff base solution is dried as with
. ~ l Na2S04 and preferably evaporated to dryness.
O ~ ~ Compound IV is obtained as a mixture of diastereo-
isomers having the formulae
H H
.'.J~`s. N - ~ ~
~= l C2H5 and
. , ~ ~ ~ ~,/~OC2H5
; H "
, ~
,.~ C6H5
H H ~
3 ~ ,OC2H5
. 0//~ >.~ '<2H5
CO2~'
- 78 -
-- -- ,
Z5Z
.~,
~ The stereochemistry of the azido and styrryl
__
ubstieuents of compound ~ has been shown by N~
~ to be exclusively cis. The diastereoisomers of IV
- ~ need not be separated for use in the next step of
ehe reaction sequence.
-~ After formation of the cis ~-lsctam compound
IV, the ester protecting group R' may, i~ desired,
be removed, e.g. by saponification, and the corres-
ponding free acid esterified to incorporate into
compound Iv another ester moiety R'. Thi~s optional
transesterification step may conveniently be used to
-~. convert an ester such as a (lower)alkyl ester o
IV to a more labile and easily removable ester such
8a a benzyl ester. Preferably, however, the desired
easily removable ester gro~p is incorporated into
starting material XI so as to avoid the necessiey of
~ later transesterification step.
-~ The cis B-lartam ester of formula IV is subjected
~- to ozonolysis in the next step of the process to
produce the aldehyde of formula XVIII. Ozonolys~s is
conveniently conducted in an inert organic ~olvent,
e.g. methylene chloride, with cooling, e.g. -50 to
-80C, in the presence af a reagent such as dimethyl
6ulfide, dimethylsulfoxide or triethylamine which
6~rves to decompose the ozon~de for~ed initially in
the ~eaction,
: I
-79-
~ . . ..
... . . . .. , .. . . ~ . ..
~ 25Z
Aldehyde XVIII is next selectively reduced to form
the alcohol compound XIII. Convenient reducing agents
- ~ for this step include diborane or metal hydrides such
as sodium borohydride or zinc borohydride. The
reduction is conducted in an inert organic solvent
.
which most advantageously is a (lower)alkanol such
,_
as ethanol or methanol or tetrahydrofuran and pre-
.i; ferably with cooling to a temperature of about 0 to
-10C.
. 10 According to one reactio~ route, alcohol X~~
is next converted to compound XIV by treatment with
acetic anhydride in the presence of a reagent selected
from zinc chloride, trifluoroacetic anhydride,
titanium tetrachloride, boron trifluoride or stannous
chloride. The three reactants in this step are
preferably used in equimolar amounts and the reaction
may conveniently be performed at room temperature.
Compound X~ is hydrolyzed to alcohol XV by
treatment with acid, conveniently an aqueous solution
of a mineral acid, e.g. hydrochloric acid. The
~t,:`~, hydrolysis is advantageously conducted at reflux
"
temperatures.
In the next step of this reaction route, alcohol
:~ XV is reacted with pyrrolidine to produce the enamine
' compound of formula XVI. This step is conveniently
effected by refluxing the alcohol and pyrrolidine in
an inert solvent, e.g. benzene, in the presence of
¦ an organic acid, e.g. acetlc acid.
-80-
52
,, ..
I~ an alternatiye reactio~ xoute, alcohol XIII
.~
is reacted with a methanesulfonating agent such as
methanesulfonic anhydride or methanesulfonyl chloride
in the presence of an acid acceptor, preferably a
~ tertiary amine such as a trialkylamine, e.g. tri-
: ~ ethylamine, or pyridine, to form the methanesulfonyl
derivative XVIII. The reaction may be conducted in
an inert organic solvent, e.g. methylene chloride,
.
and is conveniently carried out at room temperature.
Compound XVIII is then converted by treatment with
acetic anhydride in the presence of a reagent selected
from zinc chloride, trifluoroacetic anhydride, titanium
tetrachloride, boron trifluoride or stannous chloride
; to compound XIX which may then be subjected to base
hydrolysis to form the enolate intermediate XX. While
- the nature of the base is not critical in the hydrolysis
step, advantageously the base is an alkali metal hydrox-
ide such as sodium or potassium hydroxide.
Enamine XVI is then reacted with a methanesulfonating
'.'?.~ 20 agent such as methanesulfonic anhydride or methane-
sulfonyl chloride in the presence of an acid acceptor,
preferably a tertiary amine such as a trialkylamine, e.g.
triethylamine, or pyridine to produce a methanesulfonyl
derivative of formula XVII. The reaction may be conducted
in an inert organic solvent, e.g. methylene chloride, and
is conveniently carried out at room temperature.
The methanesulfonyl derivative of formula XVII is
next hydrolyzed by treatment with acid to the enol inter-
mediate of formula IXa. Advantageously the hydrolysis is
carried out by refluxing an aqueous solution of a mineral
acid such as hydrochloric acid with compound XVII.
i
! -81-
,, _,, . . . . . . . . . . . _
::
~ Z52
~ ,.
:~-
. ..
. ~ Enol i~termediate IXa is cyclized to the azido ~-2-
~r~ }~
~ isocephem intermediate Va by treatment with a base as
, ,' ~
~ described above.
,,~
. ~ In the preparation of intermediate VII, the overall
sequence of steps is as follows:
'' '
. ~ The ketal amine starting material of formula
XXII may be prepared by the following reaction
,-. sequence:
. ~ W-ICI - ICI C02R ketalization~ W A---C~ C2R'
NOH O O OH
~ ,
W~ C-- C2R'
O O NH 2
"
:'
, ,'
i -82~
.. .. .. ..
25Z
.
`- The ester o~ime may be prepared according to the
general method described by H. Adkins and J. ~eeve,
~ J.A.C.S., 60, 1328 (1939). The carbonyl group of the
;~ ester oxime is protected by ketalization with ethylene
glycol in ~he presence of acid, e.g. p-toiuenesulfonic
. acid. The ketal oxime is then selectively reduced as
with aluminum amalgam by the procedure described by
c~ D. J. Drinkwater and P.W.G. Smith in J. Chem. Soc.
(C), 1305, (1971). The product may be recovered as
an acid addition salt, e.g. HCl salt, which may be
basified to give ketal amine starting material XXII.
An alternatlve procedure for preparlng ketal
~t amine starting materials of formula XXII having
less labile ester groups, e.g. tlower)alkyl esters
~_h es eehyl or methyl, comprises seleotively.
.~.;
:-
'~
:
;.
:. ..
,
~,
.,
I -83-
1.
,, . _ . . . ... . . .. . . . ......
-
'~ 25Z
, , `. -
~ -
~ ~ reduc~ng the oxi~e g-oup of an ester oxime of ehe
~ , ~
for~ula
, ~ C02R
. .. ~ ,.^,~ l
"/ and s~bse~uently protect~ng the carbonyl group by
: r: ket~lization~ The reduction step may be conveniently
~ sccompllshed by catalytic hydrogenation and the ketal-
: izatian step is carried out as described a~ove and
-~ ~n the examples whlch follow.
Conversion o~ the ketal amine XXII to alcohol
XXVI ls effected as described above in connection
. with the process for ~reparing compounds of formula
II. Compound XXIV i5 obtained as 2 mix~ure of
. H C2R'
¦ H
- N ~ ~ J
~. - ~ , /
~ , , I ~,~f
. H C2R'
.
Tha stereochemistry of ~he azido and styrryl
substituent~ of compo~nd XXIV has been shown by NMR
., I .
I 84-
. . . . ... ... .... . . .. . .
25Z
to be exclusively cis. The diastereoisomers of XXIV
need not be separated for use in the ozonolysis step
of the reaction sequence.
Alcohol XXVI is reacted with a methanesulfonat-
ing agent such as methanesulfonic anhydride or methane-
sulfonyl chloride in the presence of an acid acceptor,
preferably a tertiary amine base such as a trialkyl-
amine, e.g. triethylamine, or pyridine, to produce
the methanesulfonyl derivative of formula XXVII.
The reaction may be conducted in an inert organic
solvent, e.g. methylene chloride, and is conveniently
carried out at room temperature.
Enol intermediate X is produced by hydrolyzing
compound XXVII under acidic conditions. Examples of
suitable reagents for the ketal hydrolysis step are
trifluoroacetic acid, an aqueous solution of BF3
etherate and 50% perchloric acid in acetone.
Following the hydrolysis step, the enol inter-
mediate X is cyclized by treatment with base to
produce the azido 0-2-isocephem intermediate VIa
as described above.
Subsequent reduction as described above affords
the 7-amino 0-2-isocephem VIII.
~ - 85 -
~ 25Z
Illustrat~ve exam?les of the p~epa.atlon of compounds
...
o. the present invention .^ollow. These examples are given
in illustration of, but not in limitation of, the present
.~
invention. All temperatures are in degrees Centigrade.
!i AR indicates Analytical Reagent grade. Other abbreviations
- .
`-P include TEA for triethylamine, THF for tetrahydrofuran,
mm fcs millimole, TLC .or thin layer chrom~tography and
EEDQ is ehe amide bond forming reagent having ehe structure
~`/i CO~Et
:~
The 7-scylamido c~mpounds prepared in the examples
which follow all have the hydrogen 8toms at carbons 6 and 7
cis with respect to each other and, unless indicated, the
products ase racemic mixtures in the sense that they are
composed of e~ual parts of the two isomers having the
foll~wing structures:
,: .. : .
,, .,
H ~ H H
.. _ _
, I ~ and ~ <
~/i C~-O-
. .
.
;'
Descri~tion of t~e Preferred Embodiments
I
.. , . , . ,.. .,, ., , . ,. . . ,, , ,_. . .. . . . .. ..
-) $11'~25Z
. I ' .
~ . ,,
Exam~le 1
H2, 10~ Pd-C
~02Et E~OH-~Cl > CH3co~co2Et
NO~ NH2-HC
Eth~l a-o~lminoacetoace~ate 1 (80 g.) ~Prepared
accordlng to the method Or ~. Adkins and ~. Reeve, JACS,
1328 (1939)~ was dissolYed ln a mlxture of ethanol
(EtO'.i; 200 ~1. USP) and ethanollc HCl (70 ml. of 9.28
N ;~Cl-~tOH; 1.25 eaulv.). ~Amounts of HCl greater and
s~aller than ~ 25 equivalents were found to ~lve lower
y~eld of 2.~ lC~ Palladlum on carbon t8 g.) was added
carefully and the mixture was hydrogenated ln a Parr
hgdrogenatlon apparatu~ startlng at 60 psig. After
absorptlon Or the theoretlcal amount of hydrogen (1 -
2 hr.) the catalyst was flltered of~ and washed withEtOH. The EtOH was removed in vacuo at 40 - 50 le2vin&
a thlck red-~rown oll. The oll was dlluted wlth 8 ~ols.
o~ acetone (AR) with vigorous ~tlrri~g. Yellow crystal3
o~ the a~.ine hydrochloride 2 separated out on coolin~J
49 g- (5~ m.p. 122-12~ (cor.) [llt m.p. - 114-116
uncor.; (~. &. Laver et al,, i. Chem. Soc., (1959),
1474.~ [Yields ranged Lrom 45 - 70~ accord~ng to the
8c~ie c~ the reactlon.] Th19 matPrial ~a~ uaed ~lth-
'.
I ~87-
j
. . . . --.. . ... . . _ .. ., . . . . . . . ~ . . . .. . .
~ 25Z
, ~
. . .
o~t rurther purl;'icatlon.
C~ COCXCO~Et X N ~ C~
3 1 > 2 `
'''~. NH2~E~Cl C~2Et
~ 3
~ ~-'
To a mi~ture of ethylene glycol (1.75 '~g., 28.2
mo~e) and p-toluenesulfonlc acld monohydrate (210 g.;
i.9~ mole~ which had been warmed to 90, amlne hydro-
chlorlde 2 (460 g,; 2.54 mole) was added wlth vigorous
~echanlcal stlrring. The mlxture was stirred for 40
min. at 90. The mlxture was then poured lnto a mix-
ture of water ~2 1), conc. ~X40H (550 ml.), and lce
(1 1), and extracted four tlmes with 500 ml. ~H2C12.
The comblned CK2C12 extracts were washed with brine,
drled t~a2S04), and e~aporated to give 491 g. Or a
dark red oll. m e oil wa~ dlluted to 1.8 1 wlth ~t20
(USP), cooled ln an lce bath, and EtOH sat'd with ~Cl
~aq wa~ added untll the p~ reached 2-3. The re~ulting
solld wa~ collected by ~lltration and washed wlth Et20 to
yield 398 g ~ hydrochloride as a light yellowish solid (70~)
m.p. 15~-6 (cor.). An analytical sample of hydro-
chloride was recrystallized ~rom 2-propanol-Et20, whlte
crystals, m.p. 158-160 (cor.).
~ Reaction times shorter and longer than 40 min.
, ~ ;
,'A. at 90 were examlned and found to glve poorer results.
-83-
. 1.
., . . _,., . _.. ... . .. . . .. . . . .. . .. . . . .
2SZ
~d
,.
Anal. Calc'd for C8H15N04 ~Cl: C, 42.58;
~, 7.15; N, 6.21.
. Found : C, 42.40;
.
. ~, 7.24; N, 6.37.
,..
The ~ree base of ~ i8 conven$entlJ preDared
rrom lt3 hydrochlorlde by bas~lcation w~th conc.
NE40H and extract~on wlth CX2C12.
' . ~
~ ~ E2N~
. ~ - 3
~ C2Et ~ / C02Et
L ~ ~
3~ o// ~ CX3
C0 ~t
; 5
'' ~,
- - A mix~ure of ketal am~ne 3 (123 g.; o.6s mole),
- clnnamaldehyde (85.9 g.; o.65 mole), and C~2C12 (3.6 1;
:
AR dried over 4d~ molecular ~leve) was refluxed through
¦ a Soxhlet apparatu~ contain$ng 200 g, of 4A~ molecular
s~eve ~or 2 hr. ~he CH2C12 wa~ then removed on a rotary
eYaporator at 40 ~lth the ~lnal trace~ o~ CH2C12 belng
, . , .. ... , , , . , . , ,,, . , ~, _ , _ ., ,
lllU25Z
. ,
': ,''
,
;~
remo~ed by pumplng down to 0,5 mm. at 25~ ~or 20
~*:
minutes. N~ lndic3ted complete ~ormatlon of lmlne
4 w~lch was used directly in the ne~t 6tep.
Crude imine 4 (ca. o.6s mole) was d~ssolved ~n
C~2C12 (~ 1; AR drled over 4A4 molecular sleve), TEA
(99.65 ml. l.l equiv.) wa~ added, and the solutlon
wa~ placed under N2 and cooled to ~-4 wlth an ice
bath. A sol~tlon of azldoacetyl chloride (85.19 g,
equlY.) ln CH~C12 (500 ml.) was added ~ith stlr~ng
o~er 4 hr. The reactlon mlxture wa~ ~tlrred overnlght
at 25 ~nd then re~luxed ~or 1 hr. The reaction mixtu'e was
cooled, washed with 10% HCl, then wieh brine, an~ dried over
Na2S04 to give 267 g. of a dar~ oil which NMR indicated
conta$ned 96 weight % of S. ~245 g.; 98%).
Anal. sample was recrystallized from methanQl, whiee
solid, m.p. 81.5 - 82.5 (cor,)
Anal. Calc'd for ClgH22N405: C, 54.06; H, 5.94:
N, 14.50.
Fo~nd: C, 59.08; H, 5.73;
N, 14.58.
~3 ~ 3
, v.
-9o
.. , , _ . .... .... . .. .... ... . .. . .
~) )
252
,
~,
. I
Ethyl ester 5 (64.31 g; 0.168 moles) wa~ dis-
, solved in 700 ml. ~F ln a 2 1~ 3 necked RB flask
equ~pped wlth magnetlc stlrrln$, 2 thermometer, an
A ~ addition funnel and a reflu~ condenser. There wa
added 670 ml. o~ 0.25 N NaOH ~olutlon (0.168 moles)
at ~uch a rate aq ~o hold the temper2ture around 25
~ (too~ 1 hr.). Stirred at 25 until TIC ~howed tha~
.
5 had completel~ reacted (0.75 - 1.25 hr.). The
~ reactlon mlxt~e was carefully acidifled ~o pH ~
;~ with ccnc. HCl,;~at'd wit~ salt, and extracted wlth
- CX2C12 ~3 tlmes). The CH2C12 e~tract~ were washed
wlth brlne, drled (Na2S04) and evaporated ln vacuo.
. ~,,
The resldue wa3 dl3solved ln Et20 and extracted with
L~ NaHC03 solutlon untll the extracts were colorless.
The comblned ba~lc extracts were washed twice with
Et20, then carefully acidifled t~ pH ~ with conc.
HCl, sat'd wlth salt and extracted ~lth C~2C12. The
. CH2C12 extract was washed wlth brlne, drled (Na2S04)
and evaporated to drynes3 ln 2CUO to g~ve 51.86 ~,
~8 ~ ) Or 6 as a brown solld. Recrystalltzatlon from
benzene provided an 2nal. 3ample as white needles,
m.p. 1~1-1.5 dec. (cor.).
Anal. Calc'd for C17HlgN405: C, 5~.98; R, 5.o6;
N, 15.64.
Found : C, 57.o6; H, 5.13;
~, 15.78.
'-91-
: -?
~ ~ 252
i L N ~ .~'A
0// ~ CH3 ~ C~
;. ~ .`~,`.~, 2H CU2C~
- ' ' .
. 6
.
Carboxylic acld 6 (128.01 g; o.~8 mole) wa~
i~ dl~solved ln CH2C12 (1 1.) and TrA (~9.8 g; 0.394
. mole) wa~ added lTne carboxylic acld 6 re~erred to
was the crystalllne ~olid, m.p. 131-131.~, which is one
~' Or the l~omers.]. The mixture w2s cooled ln an lce-
.;; ~alt bath to 3 and then a mixture of benz~l chloro-
,' r~ form2te (67.5 g. of 88.6 welght ~; 0.394 mole) and
~- ~ CH2C12 (200 ml.) was slowly zdded keeping the
.-,.. ~ react~on temperature at 3. After the addltlon wa~ -
complete, the reactlon mlxture was stlrred at amblent
_ ~ temperature for 30 mln. and then refluxed gently untll
evolutlon of C02 cea~ed (cz . 30 mln. ) . Worked up by
~ . washln~ wlth 10~ HCl, lO,'g NaXC0~, brlne, dried (Na2S04)
a~d e~aporated to dryne~s ln vacuo to yleld 161.10 g.
.~: tlOO~) of crude ~;. Cryst211ized ~rom be~l2ene-petroleum
ether (30 - ~0) to give 143.60 g. (9~) of ~, as a light
: . . belge solld, m.p. 65.5 - 66.5 (cor,).
.~ Anal. calc'd for C2~2~.~N405: C, 6~.27; H, 5.39;
N, 12.49.
.- Found: C, 6~.13; ~, 5.~6;
N, 12.48.
-92-
... . . . ... . . . . . .. .. . . .. . . . . . .. . .
- -
'I , ,
~ )252
,.f~
` /0
, N3 ~ I N
I o/~O ' ' ~ o
v~*~ /~ ~ 2, (C~)2S / ~ ~ ~ CH
' C02C~20 C02CX20
.
's
7 8
,,
. ,
~,, Styryl ~-lactam 7 (36,36 g; 81.24 mm) LThe styr~l
' ~-lctam 7 used ln thls experlment was princlpall~ on~
, o~ the possible 130mers.] was dissolved ln C~2C12
~300 ml.), cooled to -50 to -60 ln a dry lcP-acetone
batn, and ozon1zed untll a ~aint blue color appeared.
The solutlon was then flushed with 2 untll,the blue color
; ,-~ - faded. (CH3)2S (31.87 ml; 5 equiv.) was added to the
-50 solutlon, whlch ~as then allowed to slowly reach
25 as the coollng bath gradually melted. Kept at 25
' under N2 overnlght then washed twlce wlth 1~ ~aHC0~,
, twlce ~It~ brine, drled (Na2S04) and evaporated to
dr~ness. Thls provlded 32.92 g. o~ ~ an oll whlch
crystalllzed on standlng. ~nl~ materlal Wa9 slurried
wlth ether and ~iltered to provlde 18.84 g. (6g~) o~-
white 3011d ~" m.p. g~-100 (cor.) . 'The analytical
sample was recrystalll~ed fro~ et~er, white cr~stal~,
r3. p . 101-2 ( cor, ) .
-93-
?
25z
;
~, .
,.~ I . .
~. ~, . .
.`'
Anal. C21c'd for C17El~N406: C, 54-54; H, 4-84;
Found: C, 54.75; H, 4.87;
~s N, 14.89.
; . ; OH
3 ~ ~ Na
~/ ~2CX20 ~ ~0>2CE20
8 / 9
, ~ c02~203
-' ~ 1, 10
! ~
.
: ~ Aldehyde 8 (47.15 g; 0.115 mole~ was dlssolved in
..j !
~ n~ ~400 ml; AR) and the resultant 3clutlon cooled to -~
to -10 (lce-~eCH). Na~H4 (~.152 g; o.576 mole~ was
added, wlth stirrlng, ln three portlon~, After 25 min.,
TIC indicated complete reactlon of aldehyde 8. The
reaction mixture wa~ carefully acldifled to pH 3 ~ith
I 10~ ~.Cl, dlluted with 100 ml. of brlne, a~d extracted
wlth ether (~ x' 8 200 ml.). The combined ether extract~
-94- .
!
..... . . . .. . . . . . . . . . ..
~ ZSZ ` ~
. .
~. ~
~:
were washed with brlne (2 ~'s 150 ml.) J drled (Na2S04),
and e~apor~ted to dryness ln _acuo. Thl8 provlded
48.7 g, o~ O as a red oil (contalnlng some ~F) whose
IR and NMR conflrmed the structure ~ [Eplmerlzatlon
occurs at the po~ltlon ~ to the ester group durlng
thls reductlon.]. mi8 ma~erlal was used aq 3uch
ln the ne~t reactlon.
Crude alcohol ~ (42.~7 g; 0.11~ mole) and TEA
~17.07 ml,; 0.~24 mole) were dissolved in CH2C12-(400
:~, ml. AR o~er 4A molecular sieve), placed under N2
8~mo~phere and cooled to O to -5 (ice-MeOH). Methane-
r 3ul~0nyl chlorlde (14,15'g, ~.124 mole) dlssolved ~n
C~2C12 (100 ml, AR) wa~ added over 1~ mlnutes. After
1 hr. at ambient temp. the reaction wa~ ca. 80~ complete
(~C). After 3 hours, the reaction mixture was washed with
water and then with brine, dried over Na2S04 and evaporated
to provide 56.1 g, of brown oil, This oil was dissolved in
the minimu~ amount o benzene and chromatographed ove, 700 g,
.
of ac~Yated alumina usin~ EtOAc-Et20 (1:3) as eluting solvent.
30 g, of pure crystalline mesylate ~ was obtained from the first
liter of eluen'. 4.2 g. o~ sllgh'ly impure me~ylate
Wa8 obtained as a forerun. Total yleld _ 66Z ~r~m 8.
Anal. sample was crystalilzed from benzene-ether, whlte
crystal~, m.p. g7-9 (cor,).
Anal. Calc'd for C18H22N408S: C, 47.61; ~, 4.88;
N, 12,34.
Found : C, 47.56; H, 4,93;
¦ N, 12.~.
_95_
.. . .. .. . . . . . . . . .
25Z
. .,
' .,
; N~ ~S2CH3 N_ IS025H3
~l--\ -- > ~S
. ~ C2 ~ ~ C02C~
~,
.. 10 / 11
,, ~ /
., I Base/
'~, ~ '
~j o/~
CH20
.~,
~- 12
- - ~ . - ' .
Ketal 10 (~.l9 g; 6.4~ mm) waq placed in a 100 ml.
~i~ ~hree-necked round bottom ~lask equlpped wlth ma~netlc
stlrrlng. 95~ TFA (30 ml.) [95~ TFA was prepared by
adding 5 ~1. of water to a lO0 ml. graduated cylinder
and dlluting to lO0 ml. wlth ~lacial TFA.~ waq added
and the solutlon waq stirred at amblent temp. ~ca. 25~)
~or 2 hr. At this polnt NMR examlnation of an ali~uot
.ro~ the reaction mlxture ~howed complete reaction. The
m~ture was dlluted wlth 10 ~ols. o~ brlne and ext~acted
times with 100 ml. (each) o~ ~H2C12. The combined
extracts ~ere drled (Na2S04) and e~aporated to aryne_s
~acuo lea~ln~ ~.17 g, o~ 11 as a heavy brown oll.
-~6-
. .
25Z
I
.
NMR conflrmed the presence o~ enol 11.
Th~ 8 m2terlal was used as such ln the next re-
actton.
Crude enol 11 (described above) (12.02 g; ca.
29.44 mm) was dissolved ln CH~C12 (100 ml.) and TEA
. (4.1 ml; 29.~4 mm) added. The mi~ture was re~luxed
under a CaC12 drylng tube ~or 2 hr, then washed wlth
~ 10~ HCl, brlne and drled (NaS04). Evaporatlon left
.. - 8.56 ~. of 12 as a llght brown oil. Thls materlal
Wa8 taken up ln CX2C12 and ~lltered thrcu~h ca. 100 g.
o~ s~liclc acid powder. E~aporation o~ the ~lltrate
, and Et20 washlngs ga~e 6,58 g. of 12 ~80.5~ ~rom 11)
.. ~ as a ll~ht belge ~olid.
A~ analytlcal...sa~ple was recrystalllzed cnce rrom
~ ether to glve whlte crystals~ m.p. 87-88 (cor.).
:j~. Anal. Calc~d ror C15X14N404: C, 57.32, H, 4.49;
t N, 17.8~.
...
. Found: C, 57.31; H, 4.58;
N, 17.67,
-97-
. . .. .. . . . . . .
lll~;~SZ
C~ EtOH > ~ N
C02~20 C0
- ~ 12 / 1~
' Ç,~
k~
~IOC~zCONYp/~o
~ o ~,~J- CH3
.~ , C0
-
: 14
~ .
.
Azido 0-2-isocephem 12 ~201 mg; C.64 mm) was dis-
solved ln absoiute EtO~ (35 ml.)~ 87~ PtO2 (100 ms.)
.:-
W2S added and the mi~ture was hydrogenated at atmospherlc
~'4~.; pre~ure. The theoretlcal amount of hydrogen (for PtO2
. reduction) was absorbed ln 7 min. and the reaction was
stopped to avoid hydrogenolysls o~ the benzyl ester.
The catalyst was filtered of. and washed with 2 vol.
¦ of Et~. Evaporatlon of the EtO~ pro~ided 0.19 ~. o~
as a yellowish oll. TIC showed no 12. This oil
~a~ used l~medlately ln the next step.
Crude amine 13 (0.19 g; o.6~ mm) was dlssolved ln
CX2C12 (60 ml.) and phenoxyacetic acld (PAA) (97.4 mg;
O.6~ m~) an~ ~DQ (158 mg; O,64 mm) were added. The
reactlon m~ture was allowed to stir at 25Q for 1 hr.
-98-
-
~-~ -- -- . .~
25Z
i ~ and then it was washed 2 tlmes wlth 1~ NaHC03, 2 tlmes
; wlth lC~ HCl, once wlth 3 vols. of brlne, drled (Na2S04)
and e~aporated to dryness in ~ . Th13 provlded 0.18 g.
of 1~ a~ a yellowlsh ~um which was trlturated wi~h dry
Et20. The ~t20 trltur2nt waq cooled at 0 o~ernl~ht.
.. Ihe resultant crystals were collected by flltratlon
. - and wa~hed once wlth petroleum ether (30 - 60 ) to
.~ giYe whlte crystal~ Or 1~, m.p. 133-1~5a dec. (cor.).
.. Anal Calc'd for C23X22N206
N, 6.63.
. Found: C, 65.22; '~, 5.31;
~ `1
~; ~, 6.86.
. .~,
0OCH2 CONH~Gr/~q
GH3
, 02CH20
. 14
~2~ Pd-C
0C~2 coN~f o
,~ C02H
_99_
.. . .. . . . . . .. . . . . .. .
- - - - ~ ~ -
:` ~ 25Z
::
~:
.
,~ .. .
-~ Benzyl ester 14 (lOO mg; 0.2~7 mm) was dlssolved
~- in a mixture of absolute EtOH (lO ml.) and THF (7 ml.).
.
10~ Pd-C (lOO mg.~ Nas carefully added and the mixture
wa~ hydrogenated at atmospherlc pressure. Hydrogen
~ uptake was complete afler ca. 7 mln. m e catalyst
.~ was flltered of~ and washed once wlth EtCH. The EtOX
~: ~
- wa~ remo~ed in vacuo leavlng 90 mg. of partly crystal-
~ line resldue. ~he resldue wa~ crystalllzed from acetone-
.' U~ ether to provlde of~-whlte crystals o~ ~, m.p. 171 -172
dec. (co~.).
Anal. Calc1d rOr Cl6Hl6N206 C, 57
N, 8.43.
Found: C, 57.67; H, 4.g7;
N, 8.34.
A sample of compound l5 prepared above whlch can
be named 7~-phenoxyacetamido-3-methyl-0-2-isocephem-4-
carboxylic acld (called BC-L8) a~ter soluti~n ln water
and dilution wlth Nutrlent Broth was found to exhibit
. .
the ~ollowlng Minimum Inhibltory Concentrations (M.I.C.)
ln mcg./ml. versus the indicated microorganisms aq
` determined by overniFht incubatlon at ~7 C. by Tube
dilutlon. Cne old, orally absorbed cephalosporin
.. ~ ~ cçphalexin) was included.
-100-
1,
.
. .
~ ?25Z
- ~?~1:)1 P~,
M~I.C. ln mc~,/ml,
.. ~ Organism 3C-I8 5~E
D. pneumonlae A9585 .5 .6
~5~ serum~
: Str. Pyogenes A9604 .5 .6
5~ ~erum~
S. aureus Smlth~ A9537 5 1.3
. S. aureus Smlth~ A9537 2 -2.5
. t5 ~ ~erum
S. aureu~ BX1633-2 A~o6 2
at 10- dil'n
,~ S. aureus BX1633-2 A g~o6 32 2
.~ . ~t 10 2 dll'n
Sal. en.terltldls~ Ag531 8 2
. coll Juhlt A1511963 4
~ ~. collt A9675250 16
- .;~';~. K. pneumoniae~ A9977~2
. pneumonlae~ A15130500 16
Pr. mlrabllls~ A990016
Pr. morganll~ A15153500 >125
Ps. aeru~inosa$ A9843A500 ~125
~ Ser. marcescenst A200195 >125
: ~ Ent. cloac~e A9656500 >125
Ent. cloacae A96576~ 2
: ~ I Ent. cloacae A9659500 125
., S, aureus meth.-3 Al50g732 16
reslst; at 10
~i~. ` dll~n
. * 5 ~ Nutrient Broth - 45~ Antibiotlc Assa~ Broth
~ . -4
: j. f at 10 dilut~on.
,
: -
.. ,
:~
-101-
.. . . ... ....... . .... . . ...
: ~ ----- - -- -- -- -- ~
) )
~ 25Z
Examote 2
, .
'. -
C~3~ C02CrI20
O NOH
;~ 16
. .
~enzvl 5ximlno-Acetoacetate
The procedure was essentlally the same as that
..
-~ descrlbed for the corresponding ethyl ester by H.
:::
~- Ad~ins a~d J. Reeve, JACS ~0, 132~ (19~8).
Tn a three necked one llter ~f~a3k, fltted wlth a
thermometer, a d-opolng funnel and a ma~netic sti.rer
~ere placed 173 g. (0.9 mole) of benzyl acetoacetate
The benzyl acetoacetate was prepared as descri~ed by
Ba~er et al., J. Org. Chem. 17, ql (L952)~ and 1~0 ml.
of glaclal acetic acld. The contents were cooled ln
~ an lce-salt bath and a solutlon of 69 g. (1 mole) of
; ~ sodium nltrlte in 130 ml. of water was added over a
period Or half an hour; the te~perature was kept at
O to 10 C. After the reactlon mixture was stirred
. .
for one hour at room temperature, 400 ml. of water
was added and the stlrring was contlnued for an
additlonal two hours. The reactlon mi~ture was extracted
three times wlYh 200 ml. portlons of diethyl ether.
The dieth-Jl ether e~tracts were combined, washed once
wl'h water, three times wlth saturated sodlu~ bicar-
bonate ~olutlon and once wlth brine. APter drylng
-lC~-
_ .. _ . . ~ .... ... .. . .. ... ... . . . . ... . .. . . . . ... . . . . . . . .
.` lll~Z52
:
over annydrous ~odlum sulfate, the dieth~l ether so-
lutlon was evaporated leavlng l~ as 2 clear oll w~,lch
olidlfled upon trlturatlon with ?etroleum ether
(~0 - 50) to give i86.5 g. (9~.2~) of whlte solld.
Its NMR spectrum was consistent wi~h the asslgned
struc~ure. Generall~ the product was used ~s such
ln subse~uent reactlon but lt can be recrystalllzed
..
rrom toluene, m.p. 81 - 82 C.
~.
C ~ 2~ 3 ~C~- C-C02CH
;~ ~ O NOH ~ O NO~
.. ~ \ /
16 ll
. .:
i. ~. ~ .
~enz~l Oxlr,ino-Acetoacetate Ethvlene Ketal
In a two llter flas~ fltted with a Dean Stark
. water separator and a condenser were placed 1~6.5 g.
~0.85 mole) of benzyl oximlno-acetoacetate (17),
62 ~. (1 mole) Or ethylene glycol, 80o ml. of benzene
~ .
(reagent grsde) and 2 g. of toluenesulfonic acld. The
reactlon m~xture was bolled at reflux until 15 ml. of
water was removed (3 hours). The benzene solution
wa~ washed once with saturated sodlum blcarbonate
sGlution and once with ~rl~le. After drylng over
anhydrou_ sodium sulfate, the ben~ene solution was
evaporated, leavlng 212 g. (94~) of 17 as a light
yellow oil. It3 NMR spectrum was conslstent with
, . ... .. .... ...... . ... ... .. .. ..
` ! -) -)
~ 2SZ
.:'
. ~
the ass~gned structu~e. Generall~ the compound wa
u~ed as ~uch ln subsequent reaction but one of the
-~ ~somers can be crystalllzed in 35~ yleld from
~oluene-petroleum ether, m.p. 52 C.
~,
~' '
-:,. ~ C - C02C~2~ ~ CX~ - C02CX20
17 18
., ~ v~
.,.'~
~zvl Amlno-Acetoacetate ~thvlene Ketal ( ~)
~ The procedure was essentially the same as that
described for the reduction of unsaturated hydroxy-
imlno ethyl esters by D. J. Drin~water and P. W. G.
Smlth, J. Chem. Soc. (C), 1305 (1971).~ tAlumlnum
amalgam was prepared essentlall~ the same as that
~ descr~bed ln "Vogel e~cept the foliowlng modlflcatlons:
: .,~
A 5% NaO~. was used.
B. The second washing w~th etAanol was omltted.
C. Dry diethyl ether was used for washlng and most
o~ the water must be dralned.]
Yogel "Practlcal Organlc Cheml~try" ~rd Edltlon.
Longemans Green & Cc., London (1957) p. 198.]
Alumlnum amalgam (from 27 g. of aluminum foll)
~reshly ~re?ared in a three-necked one liter flask
was covered wlth 500 ml. o~ dlethyl ether. The flask
--10~--
.
.... .. . . . . ~ _ .. . . . . .... . .. . . . . . . . .
:?
Z5Z
..:
i
. .
; ; was fitted wlth a mechan~cal stlrrer, a conden~er,
and a dropping funnel 132.5 g. ~0.5 mole) of
~ti benzyl o~lmino-acetoacetate ethylene ketal (17)
~n 300 ml. of wet dleth~-l ether was added dropw~se
at such a rate as to malntain bolllng at reflu~.
i A~ter ~tlrring for four hour~, the reactlon ~lxture
: wa~ filtered through a Buchner funnel. The L lltrate
.,
was e~aporated leavlng 110 g. of 18 as a yellowish
oll. m e oll was picked up ln 800 ml. of dry dlethyl
etAer ~nd dry hydrogen chlorlde wa~ pas~ed ln to give
io8 g. of whlte hydrochlorlde salt of 18 which was
collected, m.p. 157-158 C.
To obtaln the free base 18, the hydrochloride salt
was suspended ln 500 ml. o~ diethyl ether, concentrated
ammonlum hydroxlde wa~ added wlth shaklng untll most of
the 3011d went lnto solutlon, then washed twlce with
brlne. A~ter drying over anhydrous ~ulfate, the solvent
..~
was evaporated leavlng 90 g. of 18 as a colorless oll
(71~). It~ NMR spectrum was consistent with the
a8signed structure.
-105-
...... ., .. _ .. .. . . .. . . . . .. . . . . .. . . . . . . . . . .. .. .
:` ~ ZSZ
1~
~ 0-CH_CH-CH0 ~ ~
, , C}~ C02C~2~ C02~20
:
: 1 18 L~ 9
. .~.
~ 0 ~ 3
: ~ ~ 2CH20 ~ -
,~ .
.~ 20
~ ~ _
,~, . ..
.~J Schlff Ease Formation: In a one llter flask fltted
~i wlth a Dean Stark water separator and a condenser
- were placed 70.3 g. (0.28 mole) benzyl amlno-
~_ acetoacetate ethylene ketal (18), ~7 g. (0.28 mole)
cinnamaldehyde and 750 ml. o~ meth~lene chlorlde.
The mixture was boiled at re~lux for hal~ an hour
and ~hen 400 ml. Or methylene chlorlde was dist~lled
and removed through the Dean Stark water separator,
The ~ncentrate~. qolution was first dried over
anhydrous sodlum sulrate and then evaporated co~pletely
on an evapor2tor to drlYe the reaction to completlon.
-106-
.. . . ..... .. . . ... . . ... . .... . . . ... . .. . . . ..
25Z
The res$dual,oily 19 was checked by NMR to ensure
complete Schiff base formation before contlnulng on
the ne~t ~tep.
~Lactam ~ormatlon: The freshly prepared Schlfr base
(1~) was diluted wlth 600 ml. of methylene chloride
and cooled to 0 C. (lce-salt bath). [All the methylene
chlorlde ut~ed ln the cyclo addition reactlon wa~ reagent
grade whlch was flrst dr~ed over molecular sieve
(Type 4A) and then o~er anhydrous calclum chlorlde.
t, 31.1 g. (o.308 mole) of trlethylamlne was added and
:,-"
followed by a solution of 36.2 g. (o.~o8 mole) of
azido-acetyl chlorlde in ~62 ml. Or methylene chlorlde
addlng dropwlse at 0 C. over a period of one hour.
The reaction mixture was stlrred for an addltlonal
hour at room temperature and then evaporated on a
laqh e~aporator at reduced pressure whlle being
heated on a ~5~ C. water bath; thls operatlon ls
. .
nece~sary to ensure complete ~-lactam ~ormatlon.
The re~ldue was dlluted with 500 ml. of dlethyl
ether and filtered. The flltrate was washed twlce
with brlne and dried over anhydrous sodium sulrate.
Evaporation of thls ~olutlon yielded 117.5 g. (94%)
o~ product 20. Its NMR and IR spectra were consistent
wlth the assi~ned structure. Generally, the product was
used as such ln subsequent reactlon but one of the lso~ers
can be cryztalllzed from dlethyl ether,
-107-
- ~ )Z5Z
Com~ound 20 is identica with compound 7 prepared in
Example l 2nd ~s r~acted accord~ng to the procedures of
Exa~?le 1 ~o produce benzyL 7~-a~ino-3-methyl-~3-0-2-
- isocephem-4-carboxylate having formula
, E~ t~
.' ~ H2N - -
~, ~ ~ H3
~ l3 C02C~20
: ~ A ~ixture of amine 13 (430 mg,; }.44 mmole), ~-carbo-
. ~. benzoxy-D(-)-phenylglycine (422 mg.; 1.49 mmoie), EEDQ
~ ~-
~ . (368 mg.; 1.49 mmole) ând 30 ml. CH2Clz was stirred at
.: :,
. -:.~. 25 for 1 hour. It was then washed with 10% ~Cl, 1%
N2HCO3 snd brine and dried over Na2S04, Evap~ration
.~
O ~ ~n vacuo gave 0.85 g. of a white foam which was crystallized
.~ ~r~m ether-pent2ne and then fr~m MeOH.
~'-5-~i~''. ' ~nal. Calc'd for C31H29N307Ø5 H20: C, 65-95;
,,i~
:~ H~ ~.36; N, 7.44.
, ..
. Found: C, 66.12;
X, 5,30; N, 7.57.
The wh~te fOâm w2S characterized by I~ and h~ to be
~he N-protected compound of form~la
H H
. 0'-CIHCONH ~
~02CH2~o/ ~ ~ CH3
CO~CH
¦ -lo- .
. .
_ . _ . ... . . .. . . . . . . . .... . . .
-? --
ZSZ
, ~, ~ixtu.e Oc the above N-prot~cte~ intermedizee
(28; Fg.), 600 mg, of 30% P~-ciâtc~sceo~s earth and 10 ml.
of ethahol was hydrogenat2d at 25 at 50 psig in a Parr
hyd~ogena~or. After 0.5 hour, the caeaiyst was filtered
-~s o~r^ and the riltrate was evaporated to dryness in vacuo,
, ~.
: ~ ~be resultant residue wac covered w~th CHC13 and then
, . HCl gas was int,roduced, Addition of ethes produced a
precip~tate w~ich was filtered off and dried in vacuo,
, ~,
" The product, a yellowish solid, decomposed at 177-182
~ ~corrected) and wa~ characterized by IR and NMR as 7~-
: ~ ~-c-aminophenylacetamidoj-3-me~hyl-~3-0-2-isocephem-4-
. -
, carboxylic acid hydrochlorlde (called BC-~9) of the
formula
~-CH-CON~ ~ o
N~2 ~ cl~H2O
;~ o~_N~ C~3
~ ~ C02H
,.
., Anal Calc'd for C16H17N3Os.HCl H2O: C, 49,81;
H, 5.22; N, 10.89.
Found: C, 4g.76;
H, 5.21; N, 9.11.
~ A sample of BC-L9 after solution in water and dilution
,: with hutrient Broth was found to exhibit the following
; M~nimL~ Inhibitory Concent.ations tM.I.C,) in mcg./ml.
versus the indicated microorganisms as determined by over-
night incubation at 37C. by tube dilution. One old, orally
aDaorbed cephalosporin (cepha~exin) was included,
.
~ ~/
25Z
. Table 2
.
.~,C. in mcg./ml,
0-zanism BC-~9 Ceoha-
. -. lexin
D, pneumoniae A9585 .S . -.3
~5% serum~
St_. pyogenes A9604 .5 .3
. -: ~5% serum*
. S. aureus Smith ~ A9537 2 1.3
S ~ aureus Smith ~ A9537 16 2.5
. 1 ~50'~. serum
. S. aureu BX1633-2 A9606 8
: :~ I at lO ~ dil'n
S. aureus BX1633-2 A960632 2
: at 10-2 dil'n
S. aureus meth.- A15097 32 16
:~ ' resist; ~ t 10-3
.~ . dil'n
Sal. enteritidis ~ Ag531 16 4
. E. coli Juhl $ A15119 32 4
E. coli $ A9675 63 8
K. pneumoniae ~ A997716 4
,;~ I K. pneumoniae ~ A15~3063 16
: ~r. m~rabilis ~ A99006~ 8
. Pr. morganii ~ A15153250 >125
Ps. aPruginosa ~ A9843A~500>125
Ser. marcescens ~ A20019 500 ~125
Ent. cloacae A9656500 >125
Ent. ~loacae A965732 4
Ent. cloacae A9659125 ~125
* 50% Nutrient Broth - 457. Antibiotic Assay ~roth
~t 10-4 dilution.
110
, .
5Z
.:
; _xample 3
7B-Amino-3-methyl- ~3-0-2-isocephem-4-carboxylic
acid
H H
=
H N - - ~
2 ~ `O
O ~ ~ 3
~: C02H
A mixture of benzyl 7~-azido-3-methyl- ~3-0-2-
; isocephem-4-carboxylate (314 mg.; 1 mmole), 30% Pd-diatom-
- aceous earth (274 mg.) and 25 ml. of absolute EtOH was
hydrogenated at 25 and atmospheric pressure. Hydrogen up-
take was complete after 20 minutes. The reaction mixture
was then warmed to 40, the catalyst was filtered off and
washed with 1 volume of EtOH. The combined filtrate and
washings were evaporated to dryness in vacuo to provide 140
mg. (71%) of white powdery residue which was identified by
IR and NMR as the title product. Decomp. ~ca. 209 (cor).
; nal- Calc d for C8HloN2O4 0.5H2O: C, 46-38;
H, 5.35; N, 13.52.
Found: C, 46.86;
H, 5.35; N, 13.58.
A sample of the above compound (called BC-L61)
was found to inhibit S. aureus A9537 at a concentration of
>125 mcg./ml., E coli A15119 at a concentration of
>125 mcg.~ml., ~. pneumoniae A9585 at a concentration of
. _
>8 mcg./ml. and St pyogenes at a concentration of >8 mcg.
ml.
~:
;, ~ - 111-
''-
' ' '' ''
25Z --
Example 4
Benzyl 7~-Amino-3-methyl-~3-0-2-isocephem-4-carboxylate
; ~ ~ H2S, TEA H N H H
:' ~y ~ CH2C12 ~\
C02CH2,0' C02CH~
12
, . ~
¦ H2S gas was bubbled into a solution of 2.0 g. (6.35
ii mmoles) of benzyl-7-3-szido-3-methyl-~3-0-2-lsocephem-4-
carboxylate (12)~4.2 ml. (30 mmole) triethylamine, and 50
, I ~1. of AR methylene chloride contained in a 100 ml. 3 necked
flask equipped with a condenser, a gas inlet tube and
magnetic stirring The solution color changed from color-
~; ~ less to orange and a gas (N2) is evolved. TLC after 20
minutes showed that the reaction was complete. The reaction
~ ~ mixture was evaporated to dryness and the resulting yell~w
h ~I resldue was shaken three times with a 1:1 mixture of 10%
1 a~ueous HCl and ether. Almost all of the residue goes
....
into solution. The aqueous layer was separated and the
ether layer (yellow colored) was washed with 1~/. aqueous
HCl. The combined HCl phases were washed once with ether
and then carefully alkallzed with solid ~aHC03. The
alkalized aqueous phase was extracted twice with CH2C12.
The CH2C12 extracts were combined, washed twice with saturs-
ted ~rine, dried (~a2S04) ~nd evaporated to dryness in '2CUO.
-112-
... . . . .. .... . ..
Z5Z
:
;~ This provided 1.25 g. (68%) of a gummy residue (some black
impurities) ~hich crystallized upon standing overnite.
NMR on this material indicates a purity of at least 95%.
The solid could be recrystallized from ether to give a
white solid, mp. 91-92 (cor).
~nal. Calc d for Cls 16 2 4
Found: C, 62.54; H, 5.51; N, 9.65.
Example 5
7~-Phenoxyacetamido-3-benzyl-~3-0-2-isocephem-4-carboxYlic
~ 10 acid
., l
~ 0OCH2CONH H H
~~0
~` N ~ CH2~
. . , CO 2H
, 0CH2COCl + EtO-Mg-CH(COOEt)2 ~~~~ 0CH2COCH(COOEt)2 ~+
~ 0CH 2COCH2COOEt
The ethyl f-phenylacetoacetate was prepared after the
'a procedure describedl in 40% yield. B.P. 0.005 mm 103-105.
0CH2COCH2COOEt + 0CH2OH ~ ~ 0CH2COCH2COOBz
A mixture of ethyl ~-phenylacetoacetate (166 g.; 0.76
mole) and benzyl alcohol (100 g.; 0.92 mole) was immersed
into an oil bath, preheated to 170, and with stirring the
ethyl alcohol produced was distilled off. With an aspirator,
a forerun fraction (B.P. 100 mm 65-80) was removed and
1. G.R. ~mes and W. Davey. J. Chem. Soc. 1957, 3480-87.
. .
~ -113-
.. ... . .
~ 252
~''''
~:
. ~ne.lly the residue was distilled At low pressure. B.P.
, .
0,002 mm 155-157. By recycl~ng the forerun, a further
~uantity of pure compound was obtained. Oversll yield was
. ~
171 g. ~84%),
HN02
~CH2COCH2COOBz ~CH2COI-COOBz
NOH 55
A solution of benzyl r-phenylacetoacetate 54 (85.5 g.;
0.32 mole) in glacial acetic acid (400 ml.) snd water
(150 ml.) was cooled to 5 in an ice bath snd while stirring
, :~
~ vigorously, to it was added dropwise in 4 minutes a solution
-~ of sodium nitrite (25.5 g.; 0.37 mole~ in water (lQ0 ml.).
.
The reaction temperature rose to 16C. and was stirred with
cooling for 30 minutes more. The cooling bath was removed
and stlrring continued for 2 hours. 800 ml. of water was
added and the solution was extracted with 3 x 100 ml,
CH2C12. The combined extracts were washed with water and
brine, dried over Na2S04 and evaporated, leaving 92.50 g.
o~l. This was crystall~zed in ~0 ml. CC14 to give light
yellow crystals 52.80 g. ~567d)~ m.p. 69-70C.
~ H
~CH2-~OC - COOBZ +OH ~ 0CH2 ~ -COOBZ
A ~ixture of oxime 55t5.94 g.; 20 mm)7ethylene glycol
(1.36 g.; 22 mm) and p-toluenesulfonic acid monohydrate
(0.59 g.) ln benzene (100 ml.; A.R.) was refluxed over a
-114 -
, . .. , ,, _ _ .. _ , -- _ . . .. .... . . . . .
,
)
252
Dean-Star~ water trap for 3 1/2 hQurs. It was cooled, and
poured into 100 ~l. saturated NaHCO3 and extracted with
, benzene. After the organic phase was washed with water,
dried oYer Na2SO4 and evaporated, 6.70 g. of an oil was
~,
obtained. It was crystallized in 20 ml., CCl4, and gave
4.0 g. (57%) light yellow solid, m.p. 90-92~C.
/ \ ll Al/Hg ~ ~CH2 / C \ I COOBz
1 0
~ 56
.,
Aluminum foil (6.9 g.; 255 mm) cut into small strips and
loosely folded, was covered with 5% NaOH and allowed to
~; react for 2 minutes. It was decanted and washed successively
with water and 95% EtOH, ~hen covered with 2% mercuric
chloride, and allowed to react for 2 minutes. After decanting,
it was washed with water and ether, then covered with "wet
ether". To this amalgam with stirring was added an ether
~-~ solution of the "oximinloester", ~29~5 g~; 85 mm) in etheI
(600 ml.). There was a mildly exothermic reaction and after
the addition was complete, it was refluxed for 2 hours. It
was cooled, filtered through celite and extracted with 4 x
. .
.. .....
100 ml. 10% HCl. White crystals separated from the aqueous
phase and were filtered, washed with cold water and dried to
give 29.0 g. solid, m.p. 181-183~ with decomposition.
Recrystallized from EtOH/ether, m.p. 182-184 with decomposl-
tion. The free base was obtained by suspending the hydro-
chloride in water and alkalizing with cold concentrated
NH40H. Yield 100%.
- 115 -
_ . _ ~ , . .. , . . , .. . . . . . . . . = .
- ~ ' )
Z5Z
: ~
~nal, Calc'd, for ClgX22NO4~HCl: C, 62.72;
P., 6.0~; N, 3.B5.
Found: C, 62.83;
~, 6,14; N, 3.84.
CHO _ _
0C~2o~C~o CH-COOBz t 0 ~ > L
COOBz
H H ~ 58
~ N3C~2COCl > N3
N
.~ .
;~! 59 ~008z
:.~
Keeal-amine 57(56.70 g.; 0.173 mole) was dissolved in
~ dry CH2C12 (600 ml.) and to it w~s added cinnamaldehyde
~23.0 g.; 0.173 mole). The solution was refluxed for 30
~inutes and the sol~ent was removed on the aspirator. The
~, ,esidue was redissolved in CH2C12 (600 ml,), the flas~ was
-' fitted with a Dean-Stark water trap, and the solvent
,' `.?
terluxed while 300 ~1. of CH2C12 was coliected and continu-
ously re~oved through the trap. The residue was dried
, , .
;
over Na2so4 and evaporated eo dryness leaving 77.32 g.
light yellow oil. Thia wa~ redissol~ed in CH2C12 (300 ml.),
Triethylamine (27 ml.; 0.19 mole) was added and while s;irring
and coollng at 3-5C. in an ice-baeh ehere was added dropwise
a ~olution of azidoacetyl chloride (22.8 g.; 0.19 mole) in
CX2C12 (300 ~l.),addition being done over 2 hours. It was
kept at room t~mperature under nitro~en fos 16 hour~, and
-116-
- -
ZSZ
ref~uxed for i hour The solutlon was cooled, washed wieh
- 107. X~l, then with brine, dried over Na2S04 and evaporated
to give gO,35 g. It was used as such with no further
pur~fication.
a) 3 ~3 - CXO
N~ O i~
, COOBz 60 COOBz
`~ Styryl ~-lactam 59(11.0 g.; 21 mm) was dissolved in
~ C~2C12 (150 ml.) and ozonized at -60 until a blue color
.~.
: ~ appeared, then 2 was used to flush away the exces~ ozone.
~ ~,
~ To the solution was added 7.7 ~1. (105 mmole) of dimethyl
:' ~'~
~ 6uifide and t~e cooling bath was al~owed to warm up to
25C. spontaneously in 5 hours. The ~solution was kept at
25 for 16 hours then washed with 17. NaHC03 and brine,
, ,.. 7 dr~d over Na2S04 and evaporated to dryness. It was tritur^
_ sted with petroleum ether ~30-60) and the residue kept at
,. .
: 0.05 mm/Hg and 45C for 16 hours. This r~moved sll the
benzaldehyde, and left 8.07 g. oil. It was used as such
without any furthes purification.
H H H H
CCOBz 61 COOBz
A solution of aldehyde 60(2.1 g,; 5 mm) in THF (50 ml.;
,
,1 , ' ,
- -~17-
. _ , .. . . . . . ... .. . . . . . . ..... . .
?
25Z
-
':'~V
:.
..~
A.R,) W2~ cooled to -5 in an ice-salt bath and while
~tirring, to it was added sodiLm boro~ydride (0 1 g,;
2,9 mm~, all at once. It was stirred at 0-5 for 30
minutes, ehen the cooling bath was removed and stirring
continued at roo~ temperature for 30 minutes. It was
carefully acidified w~th co~d 107. HCl, ~aturated with
,.,~
~ sodium chloride and extracted with ether. The ether phas~
; ~ was washed with water, and brine, dried over Na2S04 and
- ~ evaporated to give 1.88 g. oil. It was purlfied by chrom-
stography on silica gel III, eluting with ether~petroleum
ethe~ 2:1.
~ H H N H H
-: ~ N3 ~ H C~3S02Cl 3- -
O2CH3
61 COOBz 62 COOBz
A mixture of alcohol 61 (1.10 g.; 2.6 mm) and triethyl-
- ~ amine ~0.29 g.; 2.85 mm) in C~2C12 (25 ml.) was cooled to
, .
0C. and with seirring under nitrogen to ie was added drop-
. wise a solutlon of methanesulfonyl chloride (0.33 g.; 2.85
mm) in CH2C~2 (10 ml.). It was stir-ed at G for 15 minutes,
"~.
then at room temperature for 1 hour. It was washed with
water then with brine, dried over Na2S04 and evaporated to
g~ve 1.36 ~. oil. It was used as such with no further
¦ purification,
-118-
, . . .. . , , . . . , . . ,, . , , , . , .. , , , , ~ , . . .
252
:-
.
.
~.
. ` .~ U U
1. - - ~. H H
N - CMes 95?. TFA > ~OMe9
: ~ N ~ ;,~ N,~
62 CO~Bz 63 COOBz
. ~ ~
. The ketal-mesyiate 62(1.36 g.;. 2.5 mm) was dis~olved
., ~
in g5% tr~fluoroacetic acid (15 ml.~ snd stirred at 50-55
for 2 hours on an oil bath. It was poured into br~ne and
extracted with C~2C12, Af~er washing the organic extracts
.~ w~h water and drying over 'L~a2SO4, the solvent was removed
- ,
. . ~ on the aspirator and left 1.20 g. red oil. No ~urther
purification was attempted.
.~ .,
; ~ 63 COOBz 64 COOBz
I A m~xture of crude enol-mesylate 63 (5.4 g.) and tri-
ethylamine ~2 ml.~ in dry C~2C12 (100 ml.~ was refluxed
for 5 hours. It was cooled, washed with 10% ~Cl and ~ater,
.. . dr$ed over Na2S04 and evaporated on the aspirator to gi~e
. 4.24 g. oil. ThiC was purified by chro~atography on 200
g, 0~ 8ilic~ gel III, eluting ~ith etner/petroleum ether
2:1. The ~ure compound 64 crystallized, m.p. 117-118.
119-
)Z5Z
. ~;. H .
N~ H2S H2
.i: COOBz
64 65 COO~z
.. ~ 'l_
A mixture of "azito-isocephem" 64 (0.49 g.; 1.25~m)
..
and triethylam$ne (0.9 ml.; 6,5 mm) in CH2C12 (50 ml.) was
. ..
cooled in sn ice bath and while being stirred, was saeura;ed
:'
with ~2S The coollng bath was removed and there was gas
evolution which subsided in 10 minutes. At this point,
T.L.~. showed no start~ng material remained. Attempts to
ex~ract the amine from ehe solution as its hydrochloride
failed as it is more soluble in CH2Cl2 than in waeer The
CH2C12 solution of the free base was dried over Na2SO4 and
evaporated on the a6pirator to leave 0.40 g. of a semi-
solid. It was used as such with no further purifLcation.
.,-- ~ .
;~!" ~- H ~OCH2CONH H H
I H2~ OCH zcooa ~
COOBz 66 COOBz
A colution of "a~ne-isocephem" 65 (0.48 g.; 1.25 ~m),
phenoxyacetic acid (0.19; 1.?.5 ~m) and EED~ (0.31 g.; 1.25 ~m)
in CH2C12 (100 ml.) waS stirred st room temperature for 16
hours. It was washed with 1~/. NaHCO3 solution, then with
~r~ne, dr~ed over Na2SO4 and evaporated on the aspirator
to leave 0.56 g. of a slightly yellow gum. It was used with
no f~rther purification.
-120-
Z52
- - ~OCH2CO~H H
2C0 ~ H2/Pd(0~)2 ~ ~ ~
66 COOBz 67 OOH
The "isocephem co~pound" 66 (0.49 g.; 1 mm~ was dissolved
in ethyl acetate (lO0 ml.) and glacial ~ceeic acid (10 ml,),
-~ 2~Z Pd(0~)2 on carbon (0.5~ g,) was added and the mixture
,.
was agitated on a Paar apparatus at 60 psi of H2 for 2 hour~.
The solid was flltered off on celite and the f~ltrate
!"
,
- I evsporated to dryne~s, The residue WRS extraoted with
saturated NaHC03, the aqueou~ phase was acidified with
10% HCl and extracted with CH2C12, ThiC was then washed
with water, dried over Na2S04 and eYaporated to drynesq,
-, -.~ ,
The resul;ing solid wa~ recrystallized from benzene and
~ , gave white crystals, m.p, 123-125 with decomposition.
;~ Anal, Calcld, for C22~20N26 C, 64-70; H~ 4.94;
N, 6.86,
Found: C, 64.78; ~, 4,87;
~, 6.80.
A ssmple of compound 67 prepsred above which
can be na~ed 7~-phenoxyacetamido-3-benzyl-~3-0-2-isocephem-
4-car~oxylic acid (also called BC-L17) after solution ir
water and dilution with Nutrient Bsoth wa~ found to exhibit
the followin~ Minimum Irlhibitory Concentratlons (M.I.C.)
. ,. . . ... ~ ~ . . . .
`~
~ 252
: ~ -3
. - . 4
`'` in mcg./ml. versus the indicated mlcroorganisms as deter-
mined by overnight incubation at 37C. by tube dilution.
Cep~alexin was included as a comparison compound.
,~
~ -
- ~ ~,
~-~
~; . "'
., .,
I
'' `'
~..
,
: ';
j -122-
..... ... , .. __.--___ __. ... , .. .. . , ...... .. . .. ,.. _
25Z
Table 3
M.I.C. in mc~./ml.
. Or~anism BC-L17 Cepha-
I ~ x lexin
;~ ~ D, pneumoniae A9585,25 .16
.~ ~5% serum*
:.~ Str. pyogesles A9604.25 .16
~% serum*
S. aureus Smith ~ A9537.25 .6
S. aureus Smith ~ A95371 1.3
t50% serum
S. aureu~ BX1633-2 A96068
~; at 10 dil'n
:~ ~ S. aureus BX1633-2 A9606>125 2
'. ~ at 10-2 dil'n
~$~ S. aureus meeh.- A15097 125 16
resis;; at 10-3
~ Sal. enteritidis ~A9531 32 2
.. .: F. coli Juhl ~AlSll9 >125 8
. ~ ~ E. coli ~ A9675>125 16
~ ~ K. pneumoniae ~ A9977~125 4
.; ~ K. pneumoniae ~ A15130 >12S 16
Pr. mi.abilis ~ A9900>125 4
Pr. morganii t A15153 ~125 >125
... e Ps. aeruginosa ~ A9843A ~125 ~125
- -~ Ser. marcescens ~A20019 ~125 >125
Ent. cloacae A9656>125 ~125
Ent. cloacae A9657>125 4
. Ent. cloacae A9659>125 >125
.,
* 507. Nutrient Broth - 45% Antibiotic Assay Broth
. ~ 2t 10^4 dllution.
-123-
1, . . .. .. . .. . . . . .... .
I ~) ~ ZS2
_~am~le 6
~ 7~-Phenoxyacetamido-3-~henethyl-~3-O-2-isoceohem-4-
.,~
carboxYlic acid
: H H
.~ l ~ 2CONH~
CH2CH20'
~ C02H
`~ ' '.i~l
~CX~CH~gBr I CN-CH2-COOEt ---> 0C~2CH2- C--C~2COOEe
> 0CN2CH2--ICI~2COOEt
Phenylmagnesium bromide was preparedL in the usual
, ~ way fr~m magnesium (24.30 g.; 1 mole), phenethylbromide
i ~ (204 g.; 1.1 mo}e) and a trace of iodine in ethes ~2S0 ~1.;
. ~ . A~). While maintaining ehe reaction temperature at 25-
~- ~ ~ 30C., to it was added ethylcyanoacetate (45.2 g.; 0.25
: ~ s~3 le) a~d the resulting solution was stirred at room
temperature for 24 hours. Ie was decomposed with saturated
ammonium chloride, 10% ~Cl and water and the phases separ-
. ~
ated. The organic extract was treated with 107. HCl (250
ml.) and se~rred vigorously for 3 hours. The organ'c phase
was washed with brine, dried over Na2S04 and evapo-ated
on the aspirator to give 83.5 g. oil. Fractional distil-
lation gav~ 12.67 g. (217.) pure product. B.P. 0.1 milliMeter
114-122C.
1. G. ~. Anderson et al, J.A.C.S. 67, 2197-2200 ~1945).
-124-
: - . . ,
~ ~ 25Z
~,d, ~C~2CH2~ C~2COOEt + ~CH20~i ~ ~ )~CC~2CH211CH2C00~3Z
~ ' O O
A ~xture cf ethyl ~-benzylacetoacetate (12.56 g.;
50 ~' ana benzyl alcohol (8.1 g,; 75 mm) was im~ersed
~r.to an oi~ bath preheated to 170C. and st~rred. A~eer
~ ethanol had been distilled off, the excess benzyl alcohol
; was removed on ehe asplrator and finally the residue was
d~st~lled. B.P. 0.01 millimeter, 160-163. 6.15 g. pure
p.oduct was obeained.
; . , .
2~X2cocH2cooBz-- 2_ ~ ~CH2CH2CO~-COOBz
- 68 6~ NOH
~ o z solueion of benzyl r-~enzylacetoacetate ~37.0 g.;
0.13 mole) ~n ~lacial acetic acid (50 ml.) was added drop-
wis2 in l~hour a solut~on of sodium nitrite ~10 g.; 0.143
m~le) in water tSO ml.). The reaction temperature was
kept at 24-30C. It was stirred an additional hour after
ehe addi~on then dilutêd with water (10~ ml.), and
extracted with ether. The organic extract was washed with
water and with LZ NsHC03 until the washings were basic, then
with b.ine. It was then dried over Na2S04 and evaporated
on the aspirator to leave 40.1 g. of a light yell~w oil.
.
It was used as such with no further purification.
rOH
~C~I2CH2COC-COOBz q~p NOH 70
A sn~sture of oxime (8 .48 g ,; 27 mm), ethylene glycol
~1.85 g.; 30 mm) and p-~al~enesulfonLc acLd monohydrste
- l 2 5 -
. _ .. . .. . .. .. ... . .. . . . . .
Z52 --~
~0.85 g ~ in benzene (100 ml.; AR) was . efluxed over a
~ean-Stark wat~r erap f¢r 4 hours. I. was coole~, pou,ed
onto saturated NaHCO3 and af.er shaking well, the phases
were separated. The organic phase was washed with water
and b~ine, dried over Na2SO4 and evaporated on t~e aspir-
ator to le-ve 9.4 g. of an oil. It was used without
fu~ther pur~fication.
~CH2CHz-~C~ l-COOBz > ~CH2CH2 ~ ~ C~-COOBz
70 ~__J NO~ 71 ~ NH2
~, ~
., .~
Aluminum foil (27 g.; 1 mole) cut into small strips
- and loosely folded was covered with 5% NaOH and allowed to
react for 2-3 minutes. Tt was decanted and ~ashed success-
îvely with water and 95Z EtOH, then covered with 2Z mercuric
.- . ..
ch~oride and allowed to reac~ for 2 minutes. After decant~ng,
it was washed with water and ether~ and finally covered
wi~h "wet ether". To this ama~gam with st~rring was added
an ether solution of the "oximinoester"70 (43 g.; 0.12 mole)
:n etner (300 ml.). There was an exothermic reac.ion and
sfte- ~t subsided, the sys~em W25 refluxed for 4 hours.
The inorganic m~terial was filtered on celite and the
~iltrate shake~ well with 10Z ~Cl (100 ml.~ White cryst21s
separated and were collected by filtration, washed with
ether and dried in a dessicator to gi~e 54.0 g. solid,
m.p, 186-188. T~e free base was obtained by suspending
the sol~d i~ watPr, ca~e~ully alkaliæing with cold con-
cent~ated NX4OX and extr2ct ng with C~2C12. After
-126-
- ` -
25Z ^~
.
. i
:~
-:
eYaporation of the sclvent, 27.91 g. of a yell~w oil was
. ob.eined.
~¦ ~ca2c~.2a;~ ca-coosz +~ >
N3CH2COCl N3 ~ 7Z
, ~ mixture of "amine-~etal"71 ~27.6 g.; 81 ~ and
;.~ cinna~a;dehyde ~10.7 g.; 81 mm) ~n CX2C12 (500 ml.) was
: ~ refluxe~ ove_ a Dean-Stark water trap while 200 ml. solvent
.~ ~., W85 removed. By replacing the solvent removed with fresh
~ . on2, a further 3 x 250 ml. fractions were removed also.
. . .
: Finally, the residue was evaporated ~o dryness on the aspir-
~ ~ ator and pumped down at 0.05 millimeter/Hg. and 40C. for 10
"~ m~nutes. The residue was re-dissolved in CH2C12 (250 ml.),
.
:~ trie~hylamine tll.9 ml.; 85 mm) was added and wnile stirring
. ..~
: an~ cooling in an ice bath, eo it was added dropwise in
2 '~ hours ~ solutio~ of ~zidoacetyl chloride (iO.15 g.;
. 85 ~ r CH2C12 (100 ml.). It was kept at room temperat~re
:~ u~der ni ro~en -or 16 hours and refluxed for 1 hour The
soi~-.ion was cooled, washed with 10% HCl, then with brine,
dried c~;~ Na2S04 and ev2porated on the asplra~or ~o give
44,77 g. ~ed oil ~t was used as such with no further
purLficatLon.
-127-
. .
25Z
i
~3 _ ~ a~ 03 ~3- CHO
COOBz 0
73 74 C003z
, ~"
Seyryl ~-lactam 73(6.7 g.; 12.5 mm) was dissolved in
.
C~2C12 (L50 mi,), and ozonized at -78 until a blue color
.., ~.
- appea~ed, ~nd then nierogen was used to flush away the
exce~s ozone. To the solution was added dimethyl sulfide
,~
" ~4.5 ml.; 6S m~) and the cooling bath was allowed to w~rm
2~? to 25 spontaneously. The solution was kept at roo~
~emperature for 16 hours then was~ed with 1% NaHC03 and
brine, dr~ed over Na2S04 and evaporated ~o dryness. It
was then ?umped down zt 0.05 millimeter/Hg. and 50C. for 20
hours to remove most of the ben~aldehyde. The res$due was
~hrom2tographed on 250 g, of silica gel III, eluting with;
- ~ first etherlpetroleum ether 2:1 (to remove benzaldehyde)
- ~,.
-_ 8nd ~hen w~th ether.
¦ N ~ BH <3
COOBz
74 75 COOBz
A solution of aldehyde 74(4.1 g,; 8.a ~m) in THF
(lao ml.; A.R.) was cooled to -5 and wh~le sti,ring, to it
w3s added sodiu~ borohyarid2 (~.17 g,; 4.5mm) 211 at cnce.
-128-
..... . . . .. . . . . . . .. .
252
:
It was stirred at -5C. for 1 1/2 hours, then carefully
acidified with 10% HCl, saturated with sodium chloride
and extracted with ether. The ether phase was washed with
water, and brine, dried over Na2SO4 and evaporated to give
3.8 g. oil. It was used with no further purification.
N3 ~ OH N3 H H OMes
oAo cH3so2cl ~ \~/0--0
o ~ \~/\ 0 o~ ~\0
76 COOBz
'~
A mixture of alcohol 75 (3.8 g.; 8.3 mm) and tri-
ethylamine (1.25 ml.; 9 mm) in CH2C12 (50 ml.) was cooled
to 0, and with stirring under nitrogen, to it was added
dropwise, a solution of methanesulfonyl chloride (1.0 g.;
9 mm) in CH2C12 (25 ml.). It was stirred at room temperature
for 1 1/2 hours, then washed with 10% HCl water and brine,
and dried over Na2SO4. It was then evaporated to give 4.3
g. oil. This was purified by chromatography on 250 g.
silica gel III eluting with ether/petroleum ether 3:1. 2.05
g. of pure mesylate was obtained.
N~ n3
76 COOBz ~ COOBz
Ketal-mesylate 76 (2.05 g.; 3.7 mm) was dissolved in
- 129 -
;~ ,
3L11~252
95% trifluoroacetic acid (200 ml.) and stirred at 50-55~C.
for 2 hours on an oil bath. It was then poured into a
mixture of crushed ice and brine and extracted with CH2C12.
After washing the organic extracts with water, and drying
over Na2SO4, the solvent was removed on the aspirator and
left 1.73 g. oil. No further purification was attempted.
H H H H
0Mbs 3
N ~ N
78 COOBz 79 COOBz
~
A mixture of crude "enol-mesylate" 7~8 (1.71 g.; 3. 4 mm)
and triethylamine (0.48 ml.; 3. 4 mm) in CH2C12 (50 ml.)
was refluxed for 5 hours. It was cooled, washed with 10%
0 HCl and water, dried over Na2SO4 and evaporated on the
aspirator to give 1. 35 g. oil. This was purified by chromo-
tography on 7S g. silica gel III eluting with ether/petroleum
ether 2:1. The pure cis-~-lactam was obtained as white
crystals, m.p. 97-98~ (MeOH).
Anal- Calc'd- for C22H20N44 C, 65- 34; H, 4.9 8;
N, 13. 85.
Found: C, 65.36; H, 4.96;
N, 13.97.
- 130 -
.. . ~
~ Z5Z
..
. ~,
,,~
. ~ U
3~ H2S ~ ~2 ~b
v ~--``0 80 cOoB-
A mix~ure of "azido isocephem" 80, (0,81 g.; 2 mm~
2~d tr~ethylamine ~0.56 ml.; 4 mm~ in CH2C12 (50 ml.)
, ~
: `~........... W29 cooied in an ice bath and while being stirred, was
- 3~ ~.u_aeed w,th H2S. The cooling bath was removed and there
was gas evolution. After stirring at room te~perature fo.
1 hour, the solution waS e~aporated at roo~ temperature
` t~
and partitioned between ether and 10% HCl. White crystals
~ separated and were collected by filtration, washed with
I ~ e(:her and dried to give 1.12 g, white solid, m.p. 120-123
~ ~ w~h decompo~ition. The free base was obtained by sus-
~.~
pend~g the solid in water, alkalizing with cold concen-
t~ted N~40H and extracting with CX2C12. This was washed
~- ~-~h bri~e, dried o~er Na2S04 and evaporated on the aspir-
ator.
H ~OCX2CONH H H
COOBz 81 COOBz
A solution o. "a~i~o isocephe~" 80 (0.49 g.; l.OS ~mole)~
phe-.oxya^etic acld (G.i6 g.; 1.05 mm) and EEDQ (0.26 g,;
5 mm-) in rX2C12 (50 mi.) was stirred at room temperatu e
I
--, .. .. . . . . . . . . . . . .
-
25Z
:-~
~:
fo, 2 hcu.s. It was w2shed w~th 1% NaHC03 solu~ion, tken
w ith brine, dr~ ed o~,er ~a2S04 and eva2o~a.ed ~^n the as~ir-
a~cr to ieave 0.49 g. white solid, m.p. 146-~4~C. Le was
~ed with no 'u~ther puri, cation.
, ,
.
H H ~0~2CONH H .~
~ ~2lPd(oH)2 > ~ O
- ~ ~ 0 ~ N
,,r~ COOBz COOH
(BCL-54)
A soiution of isocephem compound 81 (0.49 g.; 0.9 mm)
~n ethyl acetate ~75 ml.) was added to a prehydrogenated
sample of 20% Pd(OH)2 on carbon '0.50 g.) in ethyl acetate
~ (25 ml.). It was then stirred under hydrogen at atmospheric
A ~ pressure a~d a~ter 15 minutes, gas consumption had ceased.
Tt was fil;ered through a celite pad, washed well with
ethyl acetate, and the soivent was removed on the zspirator
to leave ~.40 g. of an amorphous solid. Ihis was sl~spended
.~,
in ethor and extracted w~th 27~ NaHC03. The a~ueous ext.ac_
was acid~'ied with 10% HCl and the wnite sol~d ccllected
; by suction filtration, washed with water and dried to give
a white sclid, m.p. 16G-162 with decomposition, ~ecrystal-
l~zed fro~ CHC13/ether, m.?. 162-163 with decomposition.
AnaL. Calc'd for C23H22N206: C, 65,39; H, 5.25; N, 6.53.
~ound: C, 65,28; H, 5.36; ~, 6.56.
--_~2--
.. . . .. . . .. . .. . .. ..
{~252
.
A sample of compound 82 prepared above which can be
named 7~-phenoxyacetamido-3-phenethyl-~3~0-2-isocephem-4-
carboxylic acid (also called BC-L54) after solution in water
and dilution with Nutrient Broth was found to exhibit the
; following Minimum Inhibitory Concentrations (M.I.C.) in
mcg./ml. versus the indicated microorganisms as determined
` by overnight incubation at 37C. by tube dilution. Cephalexin
_ was included as a comparison compound.
,
. .
:: .
i~
' . ., ;.;~
'~
" _'
~'
-133-
25Z
:
Table 4
_.I.C. ~n mc~./ml.
Or~anis~ BC-~54 Ceoha-
. D. pne~moniae A9585.03 .13
t5% serum*
.~ ~tr. pyogene~ A9604.03 .13
~5% serum*
S. 2ureus Smith t Ag537 .06 .25
S. aureus Smith ~ Ag537 4 .5
~50% serum
S. aureus 8X1633-2 A9606 8
. at 10-3 dil'n
S. aureus BX1633-2 A96Q6 ~125 4
at 10-2 dil'n
S. aureus meth.- A15097125 32
resist; at 10-3
dil~n
Sal. enteritidis ~A9531 ~125 2
E. coli Juhl ~ A15119 .5 4
E. coli ~ A9675>125 8
~. pneumoniae ~ A9977>125 2
K. pneumoniae ~ A15130>125 8
Pr. mirabilis ~ A990~>125 4
Pr. morganii $ A15153 ~125 ~125
Ps. aeruginosa ~ A9843A >125 >125
Ser. m~rcescens ~A20019 >125 ~125
Ent, cloacae A9656~125 >125
Ent. cloacae A9657>125 . 2
Ent. cloacae A9659>125 >125
* 50% Nutrient Broth - 4570 Antibiotic Asssy Broth
~ at 10-4 dilution.
--114--
2SZ
, ...
~ ~ ~xa~le 7
. ,_
.' '~
Po:assium 79-PhenoxY2cetam~do- ~ 3-G-2-isoce~.em-4-cc~oxY
,~ f~C82CO~
. ~: C~)2K
~ ~COzEt ~ C~2-C02Et NaOEt ~ Naoc~-7-co2Et
;,-;.~ ~ O NHCXO
~ 21
-. ~ ~Eto)2cHcH-co2Et ~ (Eto)2cHcH-co2Et
NH2.HCI NH2
22
Procedure: A mixture o~ ethyl N-formyl glyclnate
(21) (4~4 g., 3.46 mole~) and ethyl formate (1800 ml.)
was slowly added lnto a ~uspenslon of ~reshly prepared
sodium ethoxlde (~.46 moles, drled in high vacuum at
150~ C. for 24 hrs; the ~odlum ethoxide must be
.
completely free of ethanol as ylelds are con31derably
lowered otherwlse) in 2620 ~1. of dry benzene wlth
stlrrlng in an lce bath rOr three hours. The suspension
was allowed to stand at 4 C. for 18 hours. The
301utlon was carerull~ decanted and the solld resldue
¦ washed several tlmes with benzene. To ~he solid was
! added slowly 4~00 ml. of 15~ HCl-absolute ethanol.
I -135-
25~ '
T~e ~olutlon was stirred at 25 C. ~or 18 hou-s The
; e~hanol W23 removed by distlllation at ~educed pressure.
m e residue w2a dlssoLYed in 4.8 l te~s me~hanol, then
750 g. o~ ~odium blcarbonate was ~dded at 25 C. The
suspension wa~ 3ttrred 18 hours, rll'ered and the
~ltrate evaporated. ~he restdue was taken up ln 4
llter~ of e~her, drled over annydrou3 30dlum sul ate
8nd evaporated The olly residue was distllled to
giYe 170 g~ (28~ dlethoxyethylalanate (22),
b,p, 90-94 C. (0.1 - 0.1, mm). (Li~er2ture b.p.
71D~l mm; Elli3 Y. Brown, Chemlstr~ o~ Penlclllin
(H. T. Clarke et al.) Princeton Uhl~. Pre~s~ lg4
p. 473-534.)
me NMR and IR spectra of 22 were conslstent wlth
the aaslgned structure.
~ , ~-diethoxyethylaianate was also prepared by the
followin~ procedure: -
~ o a suspension of 49,5 g, (0,65 moles) of sodium
I ethoxide (Note 1) in 300 ml. benzene was added a solution
I of 65.S g. (0.05 moles) N-formyl ethyl glycinate in 300 ml.
I ethylfor~ate in a 3 L. flask equipped with a mechanical
stirrer at 0C. over 30 ~inutes. After stirring for l
hour, the solution clarified and was a}lowed to stand 18
¦ hours at 4C. A solld separated from the solution~ The
supernatant liquid was decanted ar.d the residue washed
w~th 30Q ~. benzene.
i
-136-
1~ 2
:
~ To the solid was added 150 ml. e.h2nol and 55~ ml,
-~ CH2C}2 and ~he suspens~on was cooled to ~-5C, .n sn ice
.
:, bath. To the aolution a stream of dry H~l g35 was added
,
; ~or 1 ho~r, The cooting W2S re~oved and the HCl gas
bubbled ~n an add~t~onal 5.5 hours aLter w~ich the solution
was sllowed to ~tand a~ 25C. for 18 hours. The excess
. ~Cl was purged by passi~g a stream of nitrogen th-ough
the solut$on for 30 ~inutes and the solution cooled to
-10C. ln a methanol-ice bath, A stream o~ ammonia WâS
~.~
; passed through the solutlon until ehe pH ~ 9.0, The
~,.
sclut on was diluted with S00 ml. CH~C12 and the solid
. smmonium chlor~de removed by filtration. The- filter cake
was washed w~th an sddieional 500 ml. CH2C12. The filtrate
w2s evâporated eo dryness at reduced pressure (bâth
temperature <45C.). The residual oil w2s extracted
w$th ether ~2 x 500 ml.) and the extracts evaporated to
tryness. The residual oil was extrac~ed into petr~leu~
ether (20-60C,) (3 x 300 ml.). The extracts were dried
over ~a2S04, filtered and evaporated to yield 54.6 g.
~v54%). The NMR and IR spectra o f ~his oil were
~dentical in all respec~s to those of suthen~ic
22. This oil could be ~sed as such in subseq-~ent steps~
Distillation gave 43,7 g, (42,57.) of p~re 22 b.p, 60-75C,
(0,005 m~ eter/Hg,),
~ote 1, Co~errial NaO~t was used, The 30% excess was
I nece~ary,
-137-
.. . . .
-- -- --
~ 52
:
:~
: .
(EeO ) 2 ~-C~ 02Et , I~- CX= e- C~dO
22 C~ ~
'-. ~0 ~ ,zO , ~
'~ Et ~ Cl ~
;~ N ~ OEt 2 2 ~ N ~ OEt
C~2E' 24 2Et
.
Procedure:
A. Preoaration of Schi f Base (23). A mixture
of 95.2 g. (0.46 ~ole) ~,B-diethoxyal~nine ethyl ester
snd 6Q.8 g. (0,46 mole) cinnamaldehyde in 1.5 L. of
methylene chloride W2S boiled at reflu~ for 30 minutes.
After this initial reflux per,od 850 ~1. of methylene
chloride were distilled at stmospheric pressure over
.5 hours. (azeotrope with water). The concentr~ted
801u' iGn was dried over anhydrous sodium sulfate (l~rge
e~cesis ~100 g.) or 1 h.our. The drying agent
-138-
--
25Z
was remo~ed by filtration and the solution of ~ evapor-
ated to dryness at reduced pressure and the residue
pumped at <1 millimeter/Hg. pressure for 30 ~in-~tes at
40C. The residue was t~en diluted to 1.3 liters with
dry meehylene chloride. '' ''
The formation of the Schiff base may be accomplished
,', in e number of ways, On a small scale the two reactants
may be mixed in a suitable solvent ~benzene, ether,
CH2C12, etc.) ~n the pre~ence of a drying agent (Na2S04,
MgS04), Alternatively the water may be removed azeo-
tropically with benzene. Inasmuch as the subsequent
reaction is done in methylene chloride the above method
is preferred. The CH2Cl2 i~ dried by passing thru an
alumina (Act I) column wh~ch removed any alcohol which
m~y be present as preservative. At the end of the
reaction a small aliquot was evaporated and the N~R
and IR spec,tra taken to check for completeness; the yield
i8 quantitative.
-139-
,
111~2tj2
~ .e-~ara~ ion of azl~o2cetvl chloride. The
a~ldo~cetyl chlorlde wzs prepared Yla 2 ~odl~lcatlon
of the me'hod of J. H. ~oye- and J. Horner, ~. Am.
Chem. Soc., II, 951 (1955).
I To 128 ~ 54 mole~ chloroacetic acld in 300
ml. o~ ~ater was added 7 ml. 50~ sodiu~ hydroxide
. 801ut~ on (0.0875 mole) and 110 g. (1.69 moles~ o,
? s~dlum 2~ide. rne slur~y wa3 contained ln a three-
necked 2 liter round-bottomed ,lask fit~ed with two
effl^lent condense. 9 and an add~tion fu.~nel. [~E
REACTION MUST 3~ DONE IN AN E~FICI~NT ~UME HOOD! The
orig~nal llteratu.e preparation used at least one
equlvaler.t of sodlum hydroxide whereas we used less than
10 mole ~.] The mixture W2S layered with 1~0 ml. ether
and heated on a steamb2th for 24 hours. The or~nge
solution ~occasionally colorless) was cooled Lo 0-5 C.
ln an ice ba~h. To the cooled 901utlo~ wa~ adde~ 300 ml.
of 1~ X2S04 ~oliowed by solid sodium chloride to
s~tur2tion. rne solution was e~tr2cted wlth ether
(5 x 200 ml.), the extracts drled ove- sodium sul,ate.
i The drylng agent flltered, and Lhe ether e~aporated beiow
¦ ~0 C. at roduced pressure. The ~. spectrum OL the
res dual oil ~ndic2ted it to be a 1/2 hydrate o~
azido2cetlc acid contamln2ted ~ith 1 ~ ether. The oll
w~ used ~ithout further puri icatlon.
To the oil cooled in 2n ice bath wa3 added ~40 g.
~2.85 mole~) thion-Jl chloride (the addltlon of the ~irst
--i~ J--
2sz
50 ml i~ slow 25 ~igo~ous ~23 evolu~lon occ~rs, the
remair.de. is added ~uic~l~). After ad~itio~g the
aolutlon was reflu~ed 2 hour6. ~ne eæcess thlo~yl
chlorlde wa~ dlstil~ed a' reduced pres3ure ( ~ 0 C.,
70 mm). The re~idue wa3 d~stllled to ~ie'd ~3 ~.
(57.2~) azldoacetyl chlorlde, b.p. 38-40 C~12-15 mm
Xg. The d~stlllatlon must be ca~rled out usln~ 2
water bzth the temperature OL which must ne~er e~ceed
80 C. An e~ploslon occuLred ln one run where hl~her
bath temperatures were utillzed. The NMR and IR
~pectra are consis~ent with the assl~ned structure.
C. ~-lactam form3tlon. The ~reshl~ prepared
Schlff base solution (o.46 moles in 1.3 1. methylene
chloride) was cooled to 0-~ C wlth lce bath. To
this 46,1 g. (o.46 mole) trlet~ylamine was added. A
~olutlo~ o~9 56,0 g. (o.46 moles) azldoacetyl chlor'de
ln 500 ml. methylene chloride was added dropwise over
1 hour. ~ne solutlon w2s stlrred an addltlonal 30 mln.,
washed wlth water, sat~ated NaCl solu~ion, and drled
o~er Na2S04. ~aporation of this solutlon ylelded 187.0 ~.
( ~ 98~ crude yleld) o. ~o~pou~ 24 as a reddish oll.
The compound 2~ was obtained as a mi~ture o~
dl2stereoisomers (2~a and 24~). Occ3sionally a by-
pr~duct wa~ also ob~a~ned when e~cesses OL~ azldo ac~tyl
chlorlde w~re used. Th~ by-p~o~ust ha~ been identi~led
a9 25.
-141-
25;~
. ~ ~
~< h
C02Et ~ H 02~t
2~ 24a
-t H H ~ + Jl
~/~ OEt ~
C02Et C2~t
24b 25
. ,.
Compound 25 is thought to arise from ~urther reaction
of 24a 2nd/or 24b with the acid chloride. The stereochemistry
of the 2zldo ar.d styrryl substituents of 24a, 24b 2nd ~ has
been ~hown to be excluslvely cls; no trace of tr2ns com?onent
coul~ be detected by NMR. T~e m~xture of compounds 24a and
24b w2s ~e3dily separated from 25 by colu~n chromato~raphy
~Dry-column technlque on sllica gel (15~ H20) uslng ether
as eluont).
Purlf.i.ca~lon of comffounds 24a and 24b by ch~omatc-
graph~ ~2S not satls~actory a~ losses occurred. Cnl,y
partlal ~e~aratlon could be achieved. When the cyclo-
addltlon wa& c~rried out as descrlbed ~orm3tion Or 25
i
- 1 4 2 -
5Z
., .
was m$nima1 (~2 - 5%),
Compound ~ was shown to be a single geo~etr~c~l
~somer as indicated in the diagram above.
Generally the compound 24 was used as such ln
subsequent reactlons.
A small sample o~ the crude ~-lactam 24 was
chromatographed on ~ilica gel (deactivated - 15%
t~ater) by dry column technlque using methylene
chloride as eluent. Two pure fractions (as determined
by TLC and NMR) were obtalned corre~pondlng to com-
pounds 24 and 25. The oils were analyzed.
Compound 24 (mlxture of dla~tereoisomer3)
MW= 402.~60
Anal, Calc d for C20H26N45 0-1 ~H2 12
C, 58.50; H, 6.35; N, 13.64.
Found: C, 58.48; H, 6.48; N, 13.38.
Compound 2~
MW = 356 390
Anal. Calc'd For C18H2oN404: C, 60.66; H, 5.66;
~J, 15.72.
Found: C, 60.78; H, 5.73;
N, 15.91.
.. . .
--1~3--
25Z
~ NaOH > N N
3 1~, Aqueous - - ~
C~o2EtoEott N3- ~ OEt
02H
24 o 2~ -.
~0 ~
3 ~/
"L~Et
02CH
27
procedure:
A. In a 3 llter round bottomed flask equlpped with
a magnetic stlrrer was dissolved 119 g. (o.296 moles)
Or compound 24 ln 1 llter of ethanol. To thls was
added 100 ml. of water followed by 12~0 ml. o~ 1~
aqueous sodlum hydroxlde over a perlod of 1.5 hours.
,
-144-
252
The solutlon wa~ malntained at 20 - 25 C. A~ter
sdditlon, the solutlon wa 8 stlrred l hour. To the
solutlon was added 10~ HCl to pH 3 followed by 500
ml. saturated NaCl solutlon. The aqueous phase was
e~tracted by three portlons of CXCl3 (600, 300, 300
ml.) and the organlc layer evaporated. The resldue
was re-dlsaolved in 500 ml. ether and extracted wlth
three portlons (~00, ~00, 300 ml.) of saturated sodlum
blcarbonate ~olutlon. The aqueous layer was acldifled
to pH ~ wlth lO~ ~Cl and extracted lnto CHCl~ (ln
three portlons, 600, 300 and ~00 ml.). The organlc
layer was drled over MgS04, flltered, and evaporated
to yleld 97 g. (88% yleld) o~ crude acld 26. The IR
and NMR spectra of the acld were conslstent with the
asslgned structure.
B. The acld 26 (192 g.) waa dissolved ln 1 l. t
dry CH?Cl2 with 5~.5 g. (73 ml.) of triethylamine
and cooled to 0 - 5 C. ln an lce bath. To this wa3
added benzyl chloroformate (96 g,) dropwlse over a
two hour period wlth stlrrlng. Followlng the addltlon
the solutlon was stlrred at room temperature for 30 min.
The 301utlon was waahed with water (2 x 2C0 ml.~ untll
neutral, wlth brlne solution (lO0 ml.) and then dried
o~er MgSC4. Evaporatlon af~orded 27 as a dark brown
oll. The oil was passed through a column of granular
adsorbant magnesium sllicate (Florlsll, 400 g.) wlth
methylene chlor~de to glve 204 g. (85% crude yleld)
* Trade Mark
-145-
ll~l~Z5i2
of ~he desired ester 27. NMR and IR ~?ec~ra were
compati~le wlth the as31~ned ~tructure.
; Generally 'he oll has not purifled further but
~a8 used as such ~n subseouent reactlons.
Ihe reactlon proceeds according to the follow~ng
scheme.
-CO2
.. ~ RC2~i ~ R-C-O-C-O-C~I2~ > ~-COCX20.
~ The IR spectrum o~ the crude reaction mixture
-~ lndtcates no mixed anhydrlde to be present.
~- The crude product contained the mlxture of
..;.,~
deslred dia3tereolsomeric esters, benzyl alcohol, and
a small amount of acid. The colu~n chromatography
jy;
removed much of the acld and other impurities. The
benzyl este~s a.e j~enerally not very stable to colu~n
- chromatography so purl~lcation ls usually carried out
at a later step in the 3e~uence.
.
.
' H H ~ 0 ~ H
j ~ OEt Z r, s '~ - t
;)2CH2~ C~2CH
.,
~ 28
Procedu~:
A ~olutlon of 4.8 g. ~10.04 mmoles) compound 2~
~n 80 ml. dry ~.ethylene chlor1de Kes FreFared ar.d cooled
-
~ Z52
'o -78 C. ln an acetone- dry lce bath. To thls was
-; added ozone untll a blue colcr perslsted. The ozone
~ addltlon was ended and the e~cess ozone removed by
,~.
bubbllng dry nltro~en through the ~clutlon. To the
.~ solutlon was added 5 ml. o~ dimethyl sulfide.
':~
The purpose o~ the dlmethyl 3ul~ide 18 to
deco~.po3e the lnltlally rormed ozonide.
.
:'~
~ ~ C~o
25 ~ ~/ ~ 0CHO~DMSo
The DMS0 thus produced can also react w th the ozonlde
a s shown be low
> R~ H + ~C02H+DMSO.
`,................. ~
: ..
.,._ . I
~S,~
Xe Me
The washing with the Na~C03 removes the benzolc acld
. thu~ produced.
.~
. The solutlon was allowed to come to room temperature
o~er 1 hour. The 301utlon was then washed wlth water (20
ml.), saturated NaHC03 (20 ml.), water (10 ml.), brlne,
and drled over MgS0~. The ~olutlon wae rlltere~ and
-147-
... . . .. .. .
3Ll~r~zsz
:
::
:
e~aporated to glve 5.0 g. Or an oil. The ~y-~~oduct
benzaldehyde was removed by distlllatlon at 0.05 mm. ~&.
and a bath temperature o~ ~ 65 C. The resldual oll
4.0 g. (95~) was analyzed by NMR which lndlcates 77
~roe aldehyde 28.
~ The des~ed aldehyde forms a hydr2te whlch tend~
..
to lower the amount o~ ~ree aldehyde obse~able in
the NMR ~pectrum.
H ~ . H H
C~O N~ ~ 0
~ ~ N ~ OEt "L~ OEt
C02C'~2~ C02CX
, ~ 28 2
Procedure-
...._
To 3.5 g. (9.0 mmoles) o~ compound 28 in 30 ml.
95~ etnanol at 0-5 C. was added 255 m~. (6.o mmoleg)
o~ sodlum borohydride with stirrlng. Alter 30 min. at
0-5 C. the solution was stirred an addltlonal ~0 min.
at 25 C. The solution NZg acidi~ied to about pH 4
~lth lO~ hydrochloric acid and diluted wlth ~0 ~l. ice
~ater, The squeous layer was extracted wlth chloroform
,
I -148-
' , ...... . .. . .
~ 25Z
. (3 ~ 30 ml.). The comblned extr2ct3 we.e washsd wl~h
water (2 x 10 ml.), brlne, dried over M~S04, flltered
-;........... and evaporated to yleld ~.4 g. crude alcohol 29. ~ne
~:
; oll w~s chromatographed on slllca gel ~5~ wator) wlth
. chloro~orm to yleld ~.0 g. pure alcohol 29 (85~). The
IR and NMR spectra were compatlble wlth the assigned
structure.
.,.
:
~- ~,1
. ,
..
.
~ . ,
'~
'~,,,
.
.
, -149-
. . .
-
)
Z:52
. ,,
H H H H
N~ ~ ~ E~ 0/ ~ 0_
~ ~ C02CH
-` 29 30
_ ~
.
Procedure:
~ 1,~.,.'
A m~xture o~ 3.2 g. (8.17 mmoles) compound 29,
11 ml. acetlc anhydride, and 1.12 g. (8.2 mmoles) zlnc
~,
chlorlde was ~t~ red 18 hours at 25 C. The r~action
~i
- mixture wa~ evaporated at reduced pressure and the
re~ldue taken up in 50 ml. - methylene chlorlde - 20
- ml. water. The organic pha~e was separated, washed
, ~,....
:_,.'',7' ' with water, brlne, drled over MgS04, f~ltered and
~0~ the flltrate evaporated to yield ~.0 g. of an oll.
e oll was chromatographed on 50 g. sllic2 gel
(deactlvated - 5~ water) by dry column technique using
chloro~orm as an eluent. ~vaporation of the eluent g~ve
1.3 g, (41~) of pure 30 as an oll. The I~ and . ~ spectra
were com?atlble wlth the a~s~gned structure.
~' .
-15G-
.. . . . . . . . . . . .. . . . ......
25Z
H H H
t
O O
C02C~20 C02CX
: 3~ 3
` V~
. -:
Procedure:
Compound 20~ 5-95 ~. (15.25 mmoles) was rerluxed
in ~5 ml. CH~OH and 35 ml. lC~ hydrochlorlc acld for a
perlod o~ 1 hour. The solvent W2S partlally evapor~ted
at reduced pre33ure and the aqueous resldue was
extracted with chloroform (3 x 30 ml.). The co~bined
,~ e~tracts were washed with water (2 ~ 10 ml.), saturated
brlne, and drled over anh~drous magnesium sul~ate.
The solution wa3 filtered and e~apor2ted to gl~e 4.6 g.
(87~ yield) of 31 a~ an oil. The ~ and IR spectra
v~
o~ thls oil-were conslstent with the assigned structure.
H H H H
Et >
C02CH~0 C02C~
31 . 32
proc ed urn:
A solutlon of 4.6 g. (13.3 mmoles) compound 3l,
1.03 g. (14.0 mmoles) pyrro' dine, and 900 mg. ~14,0
m~le3) aceilc acld ln 50 ml. o~ benzene ~12~ refl~xed
-151~
,. ~ JIZSZ
18 hours. The solvent was evaporated at reduced pre~-
ure and the resldual oll wa~ taken up ln 60 ml. o~
chloro~orm. The chlorororm 301utlon W25 washed with
water (15 ml.), brine, and dried o~er M~S04. The
¦ drylng agent was rlltered Orr and the flltrate
e~aporated to dryness to ~ e 3.50 g. (71~ ~ield)
j o~ crys~alllne enam~ne 32, m.p. 111.5 - 112.5 C.
The NMR and IR spectra were-co~patlble wlth the
asslgned 3tructu~e.
Ana~. Calcd for Cl~ 21N504 C, 58.2}; X, 5.70;
~`f N, i8.86.
, Found: C, 58.23; H, 5.72;
; ~ N, 19.10.
H H ~~ J
> N
` ~ ~ 0~ ~J
``-.`i' C02CH20' . C02CH20
.,.
32 33
,Procedure:
- A solutlon of 2.44 g. (6.6 mmoles) comp~und 32,
3.9 g. (33 mmoles) methane sulfonyl chlorlde and 3.3 g. (3~ oles
trlethylamine ln 50 ml . meth~lene chlorlde was stlrred at
ambient (25~ C.) temperature for 74 hours. The reactlon mlxtur
, wa~ washed with water (2 ~ 10 ml.),
-152-
. . . .. ...
2:52
brlne, and drled over Na2S04. The drying agent was
rlltered off and the flltrate evaporated to dryness.
The oll was flltered through a slllca gel column
(deactlvated - 15~ water) (16 g.) wlth chloroform to
glve 2.6 g. (90~) of crystalllne mesylate ~ , m.p.
116 - 117.5 C. The IR and NMR spectra were compatlble
~lth the asslgned structures.
OS02C~ OSO CH
H H 1 3 H H 1 2 3
C02CH2~ C02CH20
~3
Procedure:
A solutlon of 2.28 g. (5.26 mmoles) compound ~3 ln
25 ml. of acetone and 25 ml. 10% hydrochlorlc acld was
rerluxed 15 mlnutes. The acetone was evaporated at
reduced pressure and the residue extracted with
chloroform (3 x ~0 ml.). The chloroform layer was
.~ashed wlth water and evaporated to dryness. The
reqldual oll was dlssol~ed ln ether (20 ml.) and the
solutlon extracted wlth ~aturated sodlum blcarbonate
-153-
-- -- ,
:1~1'325Z
solutlon (4 x 8 ml.). The bicarbonate was acidified
to pH 4 wlth 10~ HCl and re-extracted wlth chloroform
(3 x 50 ml.). The chloroform was washed wlth water,
brlne and drled over MgSO4. The drylng agent was
f~ltered off and the flltrate evaporated to give
1.62 g. (81~) of compound 34. The IR and ~MR
spectra of 34 were compatible with the as31gned
structure.
The NMR spectrum of 34 shows two signals for
the benzyl group. This may be due to two causes -
hydrogen bonding causing restrlcted rotation or
~eometrical isomerism.
__~ ~ ~ ~N ~ ~ I OH
~CH20 ~ ~ ' ~ o,H 7
-154-
I
)
~ 2SZ
> N3 ~
co2C~2B C02CH20
34 ~5
.
- IProcedure:
To a suspenslon of 198 mg (4.70 mmoles) sodlum
hydrlde (55~ mineral oll dispersion, washed ~X with
petroleum ether) ln 5 ml. dry dlmethyl sulfo~de
(DMS0) was added a solutlon of 1.62 g. (4.27 mmoles)
* co~.pound 34 ln 5 ml. DMS0 over 5 min. wlth stlrrlnLj
- at 25 C. [Gas e~olutlon was observed to cease after
~ 15 - 20 minutes. Prolonged reactlon tlmes ~a~e lower
~ ,
yields of 35. The optlmum tlme was 45-60 m~nute~.]
. ~
`~ A~ter 1 hour, the reaction mixture was poured into
~ 50 ml. 1~ HCl-ice water and was extracted wlth chloro-
- ~ ~orm (4 x 30 ml.). m e organic layer was ~ashed wlth
- water ~3 x 10 ml.) brlne, and drled over MgS04.
Flltratlon and e~aporation of the filtrate gave 1.2 g.
Or 35 as an oll. Trituration w~th ether caused
crys~allization; 545 mg., m.p. 110, of 3~ were
collected. The N~ and IR spectra were compati~le
~lth the assi~ned structure.
I Anal. Calcd. for C14H12N~04: C, 55.99; H, ~.0,;
! N, 18.66,
Found: C, 55.23; ~, ~.02;
N, 18.91.
-';5-
~ ZS2 r)
.`
. .
% ~ H ~ H
N3 ~> ~2 ~ ~ ~ 00CH2C~{ ~ o
,' CO~C~2~ C02C~I2~ '`O~C~5'20'
~ ~7
' ' .
- ~
~: ~
d ,'.'.'~f'~ 10
~ Procedure:
2~- A. Compound 3~ (500 m~.; 1.6~ mmoles) was
dicsolved in 20 ml. of dry ethyl aceta~e. To thls
- ~ wa3 added 450 mg. of 10~ Pd/C and the solutlon was
~;~ stlrred under hydrcgen at atmospheric pressure and
r~ room temperature Lor 30 mln. The solution was
flltered througn diatomaceous earth ("Cellte")
and the fllter cake wa3hed thoroughly with methyl- -
lene chlorlde. ~vaporation of the ~lltrate yielded
~00 m~. of crude amlne ,6. The NMR and I2 spectra
o, the compound were com~atible with the assigned
¦ structure. Compound 36 was used in the subsequent
step wlthout further purlflcatlon. [On standlng some
decompo~ltlon was noted. The amlne should be used
as soon as po~sible after preparatlon.3
B. Compound ~ (500 mg.) was dlssolved 1~ 10
ml. of dr me~hylene chlorlde and cooled to 0-5 C.
¦ *Trade Mark
-156-
, ............... . . .
252
in an lce bath. To thls wa3 added 280 mg. (2.8
mmole~) of trlethylamine and 346 mg. (2.0 mmoles)
o~ pheno~yacetyl chlorlde was added 610wly. After
stlrrln~ for l hour at 0-5 C. the solutlon was
washed wlth water (2 x lO ml.) and drled over
Na2S04. After evaporation the resldual oll
was taken up in 50 ml. of ether and flltered.
e filtrate was evaporated and triturated with
ether-petroleu~ ether (1:1). The solld thus
obtalned was collected by filtration to yield
570 mg. crude amlde 37. The amlde was chromato-
graphed on a ~lllca gel column (undeactlvatedJ
(25 g.) wlth benzene-acetone (lnltlally in a
ratlo 50:1, gradually changed to l:l - 2% more
acetone every 25 ml.). The deslred amide 37 was
obtalned pure, 195 mg.
The NMR and IR spectra were compatible wlth
tne assigned structure.
H H H H
bC~2CoN}~ OC~2CO.~/\ O
02CH20C02H-
~7 ~
.
-157-
. _ --
r
;~
~ 25Z
q~ ?~ocedure.
, ,..~
,,s Compound 37 (210 ~g.; 0.514 mmoles) W2S d~ ssolved
. ~
, ln 40 ml. ethyl acetate and 1 ml. ~lacial acetic acid
! was added. Us~n~ ~10 mg. (~ 2 ~ ) palladium hydroxide
!~ on c~.arcoal as ca~aly~, the 301ution W25 hydro~enated
at 58 psl for 50 minutes.
. .-
,, The reaction mlxture was ~iltered 'hrou~h "Cel~te"
~, (twice) and the catalyst w2s wa~hed thorou~hly with
,,, chloroform (20 ml.). The ~lltrate was evaporated to
,~ dr~ness ~nd then evaporated 3 times with benzene in
.~ ,;
order to strip of~ the acetlc acld. A ~ery vlscous
~, oll wzs obtalned which was washed with 10 ml. benzene.
~;-" The resldual oll was scratched wlth 10 ml. ether.
The solld 38 wh cb formed was collected by flltratlon'
to ~leld 115 mg. (70.5~). U.V. ~max. 268, ~ ~ 9549,
No sharp m.p. was observed. (D.p. <252 C.)
:~t Anal. Calcd- for ClsH14 2 6 / Y
, C, 55.o6; X, 4.62; N, 8.56. Found: C, 55.19;
H, 4.70; N~ 9.00.
- H H H H
0OC~2CON~
- ~ ~ H 0
o2X , C023K)
-~8 39
-158-
.. . . . . . . .... . ...
ZSZ
P~Qcedure
To a ~olutlon of 30 mg. compound ~ ln 3 ml.
methyl l~obutyl ketone was added one or two drops
o~ 50% solutlon of potassium 2-ethylhexanoate in
butanol. A whlte cry~talllne material separated
almost lmmedlately whlch was collected by flltratlon,
washed wlth methyl l~obutyl ketone and dried over
P205 for 48 hours under hlgh vacuum to yleld 18 mg.
39 (53.5~ U.V. ~max. 263,~ 5528.
No sharp m.p. or d.p. could be observed.
15 13 2 6K-1/2 H20
C, 49.31; H, 3.82; N, 7.67. Found: C, 49.35;
H, 3.94; N, 8.21.
A aample of compound 39 prepared above which can
be named potasslum 7 ~-phenoxyacetamido^ ~ -0-2-isocephem-4-
carboxylate (called BC-I2) after solutlon ln water and
dllution with Nutrlent Broth was found to exhibit the
~ollowlng Mlnlmum Inhlbitory Concentratlons (M.I.C.) ln
mcg./ml. versus the lndlcated microorganl~ms as determlned
by overnlght lncubatlon at 37 C. by Tube Dllution. One
old, orally absorbed cephalosporin (cephalexln) was
lncluded.
-159-
252,
rable 5
~I.C~_ln mc~/ml,
Or~anism BC-L2 _eDha-
lexln
D. pneumonlae A9585.6 .6
~5% ~erum~ -
- Str. Pyo~ene~ A9604.6 ,3
~5% ~erum~ ..
S. aureus Smlth$ A9537 1.3 1.3
S. aureus Smlth~ A9537 1 2.5
. ~50~ serum
S. aureus BX1633-2 A~606 2.5 4
at 10-3 dll'n
S. aureu2 BX1633-2 A9606 > 125 8
at 10- dll'n
Sal enteritidls~ A9531 16 4
E. coll Juhl~ A1511963 8
E coll~ A9675>125 16
K. pneumonlae~ Aq97732 8
K. pneumonla e t A15130 >125 16
Pr. mlrabills~ A9900. 63 4
Pr. . morganllt A15153> 125> 125
Ps. aeruglnosa+ A9843A~ 125~ 125
Ser, marcescenst A20019 ~ 125 ~125
reslst, at 10 3 A15097 ~ 125 ~2
dll ~ n
~50% Nutrlent Broth - 45~ Antlblotic A~say Broth
$ at 10 4 dllutlon
-160-
._ .
Z5Z
~am~le 8
~ /0
-,~ H r ~ 0~ d
2- ~C~)2s ~ ~ OEt
I C02Et C02Et
- 24 4
-~ i ~Foce~u~e:
. ~
A ~olutlon of 4~.0 g. (0.107 mole) of compound 24
(as prepared by the method of Example 7) in 750 ml, of dry
methylene chloride was cooled eO -78C. in an acetone dry
~ ice bath and a stream of ozone passed through for 2 hours.
-~ At the end of this time the solu~ion turned bluish-gr2en
~ ~nd the ozone was replaced by a stream of dry nitrogen.
-~
~ When the excess ozone had been purged (as indicated
.~ ~.i
by the disappearance Or the blue color) 30 ml. of
. ~
dlmethyl sulflde was added. The solution was allowed
to come to room temperature (~ 25 C.) over 1 hour.
.
The ~olution was evaporated to dr~ness and the residue
-
redissolved i~ 800 ml. CH2C12. ~he ~olu~ion was washed
with water, brine and dried over M~S04. rvaporation
Or the solutlon ~ave an olly residue w~ich was dist~lled
for 18 hours at 40 - 50 C. and 0.1 mmXg to remove
benzalc~hyde. Thi~ yielded 40.5 g. of 40 a~ an oil.
The h~ spectrum lndicated 75~ free aldehyde. Th~
c.-ude aldehyde W2S used ln the ~e~t step without
rUrther p'l"if` i C2t ion.
-161-
_ ... . .. . . . . .. .
;: l~ Z52
H H H H
:~ _ - ~0
OE t ~ t
C02rt C02Et
~.
~` 40 ~1
, ~ Vl
,~
~ Procedure-
. .
. A solution of 'l0.3 g. of compound 40 ln 250 ml.
ethanol -12.5 ml. H20 was prep~red and cooled to
0-5 C. in an lce bath. To thi3 was added 1.56 g.
(0.04i moles~ odium borohydride and the solution
was stirred L or 30 mln. at 0-5~ C. To the solution
wa~ added 10~ hydrochloric acid to ?H 4. The
reaction mlxture was evaporated to dryness at
reduced 2r~ssure below 35 C. To the residue wa~
added 200 ml. of brire and the ~olutlon was extracted
with chloroform (~ x 200 ml.). The extrac~s were
drled~over Na2SC4, L llte~ed and evapora~ed to yield
37.0 g. of crude alcohol ~1. The crude alcohol ~sas
iltered th~ough a column OL ac'ivity III alum~a
(5~0 g.) uslng chlorolor~ as an eluent to yield
27.0 g~ of reasonably pure 21cohol 41 ( > 90~). The
IR and ~ ~pectra of the oil were compa~lble ~ith the
asslgned structure.
The overall yleld from compound 24 was 76.5~. It has
been foun~ ~hat che ozonolysis and reduction ?rocedure can
be co~bined by carry~ng out the oxidation in ethanal and
reducing thz ozonidz in situ with NaB~4. Thls gives an
83-85,. y_e'd o, zquimolar a~;ounts of 41 and benzyl ~lcohol.
- 162 -
, . ~ , . . . .. .
il~û2~2
.
.
A sr~lL s~.21e c~ the alcchol '~'25 pu_lfied by colu~3n
chrom3togr2phy on alumln3 (Act I} ).
A , 33 ~5
Anal~ Calcd. Lor Ci3H~2N406: C, 47.27; X, 5.71;
-~ N, i6.96.
`~ Found: C, 47.26; E, 6.85;
N, 17.15.
,
.~ H ~ , H H
:~j _ - = =
Et ~ OEt
C02Et . C02~t
r~' i ~ .
~-~ 41 42
~ _~ _
Procedure:
To a solution of 6.20 g. (18.8 mmole) of alcohol
4i in 100 ml. of dry methylene chloride was slowly
added a solutlon o~ 4.0 g. (28.2 mmole, 3.54 ~1.)
- 'r-^~x
~l~ boron trifluorlde etherate in 20 ml. dry methylene
_ chlorlde over 15 mir.. at 0-5 C. The coollng bath
_ was removed and s~lrrlr.~ W2S continued for 18 hours.
m e reactlon ~ixture wa~ fll~ered throu~h a column
activity IlI a}umina (40 g.). The column was
~ashed wlth 300 ml. chloro~or~. The elu~ed fractlons
uere e~.~aLor2ted to dr~ne~s to ~Jie'd 6.o g. of ~2 as
2n oil which by TLC analysis was at least 90~ pure.
l'he NMR and IR spectra were compatible with the
assigned str~cture [In contr2st to the meth~l es'er
dlmeth~l acet21 ar~aio~ of ~1 only one isomer was
i
j -163-
.. ..
25Z '~)
obtalned on cycllzation. Careful chromatogr2?hy Or ~2
.gave a 76~ yie ' d of one pure lsomer with the s~ereo-
. ~
chemistry lndlcated ln the ~lgure. A ~mall ~ample W25
rechromatographed ~or analysl3.
~,n 1. C lcd for C11~16 4 5 C, . 7; X, 5.67;
~ N, i9.71. Found: C, 46.54; H, 5.85; N, 19.~4.
-~,
H H H H
, ~3 ~o > N ~ o
., O / ~ O
2Et C02H
-~ 42
~rQcedure:
~; To a solution o~ 12.2 g. (4~ mmoles~ of compound
,~
r 42 ln 180 ml. ethanol was added ~175 ml. l~ sodium
h~droxide over a perlod of 10 mln. at <25 C.
~ - The ~olution wa~ tlrred an addltional 20 minutes.
- .~
~ The ethanol W25 evaporated at reduce~ pre3sure and
, `1~, id
yi the alkaline solution was e~tracted with ether
.
(2 x 200 ml.). The organic layer was dlscarded
and the aqueous solutlon acld'~ied to pH 3-4
with lC~ hydrochlorlc ac~d. The solutlon was
extracted wlth chloroform (2 x 100 ml.), the organlc
la~er washed wlth water (50 ml.), brine (50 ml.),
and dried over M~504. Evaporation gave 7.25 g. (6 ~)
o~ acld 4~. Trlturatlon with ether and ~iitration
gave pure acid 4~ , m.p. 114-115 C. The NM~ and ~R
spectra were compatlbls w~th the 2sslgned structu-e.
-164-
.......... . ... . . . . . . . .. . . . .. ..
-~ ~iL~ 52
-.
..
~1
. .
;~ .
- j . i .,
. Anal. ~aicd. for Cg~ 405: C, 42.19; H, 4.72;
~ N, 21.87.
~1 Found: C, 42.18; ~, 4.83;
~ N, 22.01.
.
'~.,~
~:
:~
,t H H .H H
~ _ ~\ ~ ~/\
~ ~ f > ~2N~ o
~y N - Or t O/~ ~ OEt
2Et C02Et
44
~ l A mlxture of 760 mg. (2.8 mmole) of compound 42,
.. ~ 925 mg. ammonlum chlorlde (17.1 mmoles) and 620 mg.
(17.1 mm.) zinc powder ln 35 ml. ethanol was stirred
a' 25 C. for 3 hours. The reactlon mixture was
- ! filtered throueh "Cellte" and the flltrate evaporated
. to dryness . The resldue wa 3 taken up lr. chloroLorm
~nd flltered throu~A 30 g. of Alumlna (Act III).
E~aporatio~ of the eluent yle;ded 578 mg. of crude
amine 44. The amlne wa3 redi3solved in 15 ml.
. ~_
chloroform and extracted into 10~ HCl (2 x 3 ml.).
The aqueous layer was neutrallzed with 30dium
blcarbonate and ex~racted into chloroform. The
e~tract3 were dried over Na2S04, fllte-ed, and
extracted into chlcrofor~. ~he extracts were
Il .
-~6~
... . . ... .. . . .. . . . .. . . ..
~ 252 -)
:.`
,.`
. ~
dried over Na2SO~, llltered, and e~apora~ed to ~ield
360 mg. of an oll whtch crystalli2ed on standlng. The
amlne 44 was recry~tallized from ether, m.p. ~8.5 -
99 C. The IR and NMR spectra were compatlble wlth
s3
the asslgned structure.
~ MW = 258.
"~,~, Anal. Calcd- for C11~18N2 5
Found: C, 51.16; H, 7.01;
N, 11.0~.
.:.
. ~;
:.
,~OC~12C02E )~(OCE2coN~
~, N ~ OEt ~ ,~ ~ ~ OEt
' C02Et ~N,LO~;t ' Co2Et
. C~)2Et
. A 44 ( ~Q) 45
-
Procedure:
A solution of 400 mg. (1.55 mmole) of compound 44,
410 mg. (1.64 mmole) EEDQ and 250 (1.69 mmole) phenoxy-
ace~lc acld ln 20 ml. dry methylene chloride was
stlrred at 25 C. for a period of 1.5 hours. The
react~on m~ture was flltered through a column of
al~lna (activlty III 8 g.) and the eluent eva~orated
to dryness. The result2nt solld was washed with
-166-
. . .
~ li.l~252 "`
'
. .
, dried over Na2S04, flltered, and eva?orated to yield
360 m~. of an oll whlch crystalllzed on standlng. The
- h
~.~ amine 44 was recrystalllzed ~rom ether, m.p. 98.5 -
. b~ O
99 C. me IR and ~R spectra were compa~lble wlth
. t~e as~lgned ~truc'ure.
-~ MW - ~58.
. ,.~ or llH18N205 C, 51.15; H, 7.03;
,.
. ~ N, 10.~5.
,.
Found: C, 51.16; H, 7.01;
. ~
^i~ N, 11.03.
, . .,
.~ .
~ 2 ~ O ~OC~2C02H ~OC~2CO~r-- '^`O
: ~ ~, N ,' OEt ~ ~ ~ OEt
C02Et ~ N OEt C02Et
, ~.
: . 44 (EEDQ) 45
., ~
.
Procedure:
~:~ A solution of 400 ~g. (1.55 mmole) of compqund 44,
410 m~. (1.64 mmole) EEDQ and 250 (1.69 mmole~ phenoxy--
.,
.-: . acetlc acid in 20 ml. dry methylene chloride was
stirred a J 25 C. for a perlod of 1.5 hours. The
reaction mixt~re was filtered throu~h a column of
alumlna (actlvity III 8 ~.) and the eluent evaporated
to ~r-Jr.ess. ~he resultl~t solid was washed with
-15?-
,' ~ --~
) ~ 252
. .~
~ . - .
~,
,'7
, ......
ether and collected by fll~ration to ~leld 554 mg.
(~0%), m.p. 162-164. Recrystallization from
chloroform-ether gave analytlcall~ pu~e amide 45,
m.p. 166.5 - 167.5 C. ~he IR and NMR spectra
were compatlble wlth the assl3ned structure.
2.417
Anal Calcd. for Cl ~ 24N2 7
~, 6.16; N, 7.14.
Found: C, 57,9~;
~, 6.2~; N, 7.~.
~ ` ,,.1.
0GCE2CO~ ~0OCE2CGNH~ G
CO2Et ~IYGEt
Erocedure:
A solution of 392 mg. (1 mmole) compound ~5
in 1~ ml. warm methanol was added to 12 ml. 1~ NaOH
:~'
at 25 C. wlth stlrring over 10 mln. After ~ hour
the methanol was evaporated and the alkaline solution
was e,-.t~acted wlth chloroform (2 x 20 ml.). m e
aqueous solutlon was acidified to p~ ~ 4 wlth 10
8-
I
2s2
.
:
.
~,
.
~Cl znd extracted with chloroform (2 ~ 15 ml.). The
s~ e~tracts were washed wlth water, dried over Na2S04,
flltered, 2nd evaporated to gl~e 200 mg. ~55~) of a
`
wh~te soild. Recrystallization from methanol-ether
gave pure 2cid ~6~ m.p. 150-151.5 C. The IR and
~ R spectra were compatible with the assigned
structures.
MW - ~4.3~3
An21. Calcd. for C17H20~207 5 3
~- ~, 5.8~; N, 7.37.
Found : C, 55.08;
N, 5.5~; N, 7.4~-
"''`~
.
H H H H
3 ~ 1) PC15
o/Y ~ ) 0 2 ~ ~ OEt
C2H C02CH
4~ 47
procedure:
To a solution of 6.25 g. ~25,6 mmoles) of compound
4~ ln 100 m}. of ether was added 5.35 g. (25.6 mmoles~
vt
ph~sphorous pentachloride. The suspension was refluxed
for 15 min. after which the clear solution was decanted
and evaporated to dryne 9 3 . The residual oil wa 9 taken
up ln 50 ml. benzene and evaporated to dryness at
-169-
.. , .. .... , ,.... . . . . . . . . . . _ ._ .... . ..
r~252
reduced pressure, Thl8 procedure was repeated thrèe
times to remove phosphorous oxychlorlde. The resldu21
oll was then pumped ln hlgh vacuum (0.05 mm Hg) at 30 C.
~or 1 hour. The NMR and IR spectra were compatlble
ror the deslred acld chlorlde,
The acld chloride was taken up ln 20 ml. dry - -
methylene chloride and was added to a mlxture of
,2.7 g. (26 ~mole) benzyl alcohol and ~,2 g, trl -
ethylamlne in 50 ml, dry methylene chlorlde at 25 C,
over a perlod of 10 mlnutes, The solutlon was stirred
~or 1 hour, washed wlth water (2 x 20 ml~), brlne and
f11tered through 20 g. of "Florl~ll". The eluent was
treated wlth charcoal (Norlte), drled over MgS04,
~lltered and evaporated to glve 7,4 g. (83,5~) of
crude benzyl ester 47, Trlturatlon wlth benzene-
petroleum ether caused crystalllzatlon, The solid
was recrystalllzed from benzene-petroleum ether to
yield pure 47, m,p. 79 - 79,5 C. The IR and NMR
8pectra were compatlble wlth the asslgned structure,
MW - 346,352
Anal. Calcd. for Cl6Hl8N405: C, 55,49; H, 5.24;
~, 16.18,
Found: C, 55.81; X, 5.36;
N, 16,40.
-170-
25Z
H H H H
N ~ ` OAc
OEt ~ -~ ~
C02CH~ 2 2
47 ~0 -.
pr~çedure:
A mlxture o~ 6.5 g. (18.8 mmole) compound ~7,
50 ml. acetlc anhydride, and 5.1 g. (37.6 mm) zlnc
chlorlde wa~ stlrred at 0-5~ C. for 30 mln. then
at 25 C. for 18 hours. The reactlon mixture was
evaporated to dryness at reduced pressure and the
resldue taken up ln 200 ml. methylene chlorlde 50 ml.
water. The organlc phase was ~eparated, washe-l wlth
water, brlne, and drled over MgS04. Flltratlon and
evaporatlon o~ the flltrate gave an olly resldue
whlch was chromatographed on 60 g. alumina (Actlvlty
III) with chloroform to gleld 5.35 g. (7~%) of
compound 30 ldentical ln all respect~ wlth that
obtained earller.
-171-
252
.
. ~ H
~/~ OEt ~ ~ Et
C02C~2~ 02CX~
/ 48
: ~
. E~ H L/
2 ON~I~/\ OEtC
CP N ~
02CH20
. ~_ .
P~cedure:
To 325 mg. (0.84 mmole) of compound 30 ln 5 ml.
~- d-y methanol was added 325 m~. zlnc powder and ~00
! : . O
~ m8. ammonlum cnloride at 0-5 C. The suspension
~ was stlrred for 1 hour, ~lltered, and the flltrate
~ evaporated to yleld 312 crude amine 48. . The IR
~ ~pectrum indlcated complete reductlon of the azldo
r~
functlon.
e crude amlne 48 was treated wltr. 140 mg.
(0.92 m~ole) phenoxyacetlc acid and 2~0 mg. (0.92
mmole) EEDQ ln 10 ml. methylene chlorlde at 25 C.
for 1 hou~-. The solutlon was washed wlth 10~ XCl
(5 ml.), water (5 ml.), brine, drled over Na2S04,
riltered, 2nd the flltrate evaporated. The crude
amlde 49 W2S chromatographed on alumln2 (Activity
III) usin~ chloroform as eluent to glve 230 mg.
~ure amide 49 ar.d an addl~ion21 lO0 mg~ o~ ~ 8~
pure amide . ~ne N~ and L~ spectra ~ere CGmpatlble
th the as~iOned structures.
-172-
zsz
H H H H
POCH CONH$~`0AC ~, ~OCH2CONH~ OEt
~N~) O~
CO2CH2~ CO2 CH
A solutlon of 110 mg. (0.222 mmole) of ~9 ln
4 ml. methanol and 2 ml. lO~ hydrochloric acld was
refluxed for l hour, diluted to 20 ml. wlth water
and extracted lnto chloroform. The extracts were
drled over Na2S04, flltered, and e~aporated to
yleld 74 mg. (75~) of the desired alcohol,50. The
NMR and IR spectra were compatlble wlth the
as31gned structure.
H H H H OH
0'0cH2Co~ ~ Jl~ocH2co~l ~
co2CH2~ C02CH20
5
~5~Q~g~e: ,
A solution of 140 mg. (0.31 mmole) compound 50,
1~0 mg. acetlc acld, and 140 mg. pyrrolldlne ln lO
-173-
. . . _ .
L~ZSZ '')
ml. benzene was boiled at refl~ for 16 hours. The
solut~on was evaporated to dr~ness, taken u? ln
chioro~orm (20 ml.), washed ~th water (5 ml.),
10% ~Cl (5 ml.), saturated NaHC03 solution (5 ml.),
brlne (5 ml.), dr-ed over Na2S04, ~llterod, and
e~aporated to yield 157 mg. crude enamlde 51 (100~.
m e I~ and ~R spectra were compa t ib 1 e wlth the
assigned structuL~e.
~ .~ CX H H ~S02C~3
~3~ ~
, - CO2C~2~ co2c~20
51 ~ 52
. ' ,,
P~
To a solution of 157 m&. (0.31 mmoie) of crude 5i
and 0.5 ml. pyrldine ln 5 ml. methylene chloride was
added 170 m~. of meth2ne sulfonyl chlori~e at 0-5 C.
The solutlon wa~ stlrred at 25 C. for 48 hours, evaporated
at reduced pressure~ taken up in chloroform, washed wlth
water and dried over Na2S04. The solution was flltered
and passed through a short column of alu~.lna (5 g.
-174-
2SZ
Actlvlty III) with chloroform a~ eluent. Evaporatlon
o~ the eluted fraction gave 170 mg. ( >90%) crude
mesylate 52. The NMR and IR spectra of 52 were
-co~patible with the assigned structure.
H H OSO2CH3 H H S2CH3
~OCH2CONH~ ~ 00CH2CONH~ PH
N ~J
C02CH20 2 2
52 5
Procedure:
A solutlon of 200 mg. compound 52 in 6 ml. acetone
and 1.5 ml. 10% HCl was refluxe~ for 15 mln., dlIuted
to 50 ml. wlth water and extracted lnto chloroform
(3 x 25 ml.). The extracts were evaporated and the
resldue redl~solved into chloroform which was ~x-
tracted with sodium bicarbonate solution. The aqueous
layer was acldified to pH _ 4 with 10% HCl and extracted
into chloroform (3 x 25 ml.). The extracts were dried
over Na2S04, filtered, and evaporated to yleld 180
mg. crude enol 53. The N~L~ and IR spectra were
compatible with the assigned structure.
.
. . . .
-175-
_ _ _ _ _ _ _ _
~l lVZ5Z
H IOS02CH3 H H
0OC~I2CO~/ ~ 00C~2CO~
C2 CH20 C2 CH20 ,
53 37
pro~edure: -
Compound 53 (70 mg.~ was treated for 1 hour
~lth 5.6 mg. (60~ mlneral oll dlsperslon - washed
wlth petroleum-ether) of sodium hydrlde ln 2 ml.
DMS0 at 25~ C. The solutlon was poured into 20 ml.
lce cold 1% HCl and extracted lnto chloroform
(3 x 10 ml.). The solutlon was washed wlth water
(2 x 10 ml.), brlne (10 ml.), dried over Na2S04,
~lltered, and evaporated to glve 60 mg. of crude
37 ldentlcal in all respects to that obtained vla
acglatlon of ~,6.
-176-
.. ~
~ Zl5Z
Ex~mple 9
BenzYl 7B-Azido-~3-0-2-isocephem-4-carboxylate
oSo2cH3
H H I H H
~N ~ CH2C1
- ' C2CH2f~ co2CH
34 35
A solution of 682 mg. (0.00174 moles) of 34 and 195 mg,
; (0.00192 moles) TEA in 10 ml. CH2C12 was refluxed for 5
hours. The solution was wa~hed with water, brine, dried
over Na2S04, filtered and evaporated to yield an oil.
Tr~turation with ether and filtration gave 393 mg. (75.5%)
pure 35. An additional 21.0 mg. were recovered f~om the
mother liquors. Compound 35 prepared in this manner was
identical in all respects with that obtained earlier
~m.p., IR and NMR).
- .
Example 10
EthYl 7B-Azido- ~3-0-2-isocephem-4-carboxYlate
H H H H
N ~ MeS02Cl, Et3N 3 ~ 2oEt
~3 ~02Et 84 C02Et
To a solution of 9.6 g. (29 mmole) of compound 83
-177-
~ ZSZ
'.
~note 1) and 9,0 ml. of triethylamine in 95 ml, cf ~ethylene
chlo~.~e at 0-5 was added dro?wise z solution of 4.8 g.
42 m~ole) of methanesulfonyl chloride in 24 ml. of
~'^i,t meehylene chloride. After standing at 25 for one hou_,
the solution was washed with equal volumes of waeer and
10% hydro~hloric acid. Evaporation of ehe solvent gave a
,...~.^;.,
yellsw oil which was chromatogra~hed on 180 g. of alumin3
,,
-~ tgrsde IIT). Elution with chloroform gave the par~ially
.
purified product 84 as a yellow oil, 5.56 g. (47Z yield).
The IR and the NMR were consistent with the assigned
s~ructure. (Note 2)
~t"~ Note 1: The purity of the starting material (compound 83)
;~ was not known with certainty but lt may have -
been le~s than 70% pure.
Note 2: The NMR indicated the product was of about 70Z
purity.
.-
~~OS02Me ZnC12 ~ ~~~502Me
ct HOAc, Ac2O
~ C02Et -- C02Et
A m~xture of 4.9 g. (12 mmole) of ccmpound 84, 10 ml.
of acetic anhydride, 10 mi. of acetic acid and 1.75 g.
(13 mmole) of ~ir~c cnloride was stirred ât 25 for 17
hours, then evaporated to a tar. A methylene chloride
~olution r~f ,he ~ar (50 ml.? was washed with e~ual voiumes
- 178 -
.. .. . . . . .. . . . .
252
.
of water, 5% sodium bicarbonate and dilute sodium chloride,
The methylene chloride solution was filtered through 15 g,
of alumina (grade III) and evaporated to give an oil.
Trituration of the oil w~th ether gave pure compound 85
as a colorless powder, 1.88 g. (45~O yield). The IR and
NMR were consistent with the assigned structure.
N3 -
OS02Me 1%NaOH THF DM~O
~ > Na ~nolate
oPf--~ ~ 86
I OEt
C02Et
~
H H
~. _
3 "'"
~ l
~N ~
87 C02Et
.
To a solution of 1.83 ~. (5,99 mmole) of compound 85
in 20 ml, of tetrahydrofuran was added 20.0 ml, of 0.25M
sodium hydroxide (Note 1) solution dropwise over 10 minutes,
The resulting solution was concentrated to 20 ml. on the
rotary evaporator at 30, The concentrate was washed wlth
chloroform (3 x 10 ml.) (Note 2). The aqueous layer was
evsporated to dryness under high vacuum, The resulting
residue (sodium enolate 86 ) was stirred with 7,5 ml. of
dimethyl sulfoxide for one hour. Water (30 ml,) and
-179-
., . . . _
I_ .
~L1Ll ~Z52
~aturated ~odium chloride (40 ml.) followed by a few drops
of lOZ hydrochloric acid were added to the dimethylsulfoxide
801ution. The reculting mixture was extracted with chloro-
form (3 x 40 ml.~ snd the combined chloroform layers were
washed with water and evaporated to give the crude-product.
Pure compound 87 was obta~ned by recrystallization from
benzene/cyclohexane, then chloroform, as colorless crystals,
0.39 g. (33% yield). The IR and NMR were consistent with
the assigned structure.
Note 1: Other concentrations of base and other solvents
(acetone, dimethoxyethane, acetonitrile) were
tried but the conditions described here gave
better yields.
Note 2: The chloroform extract gave a yellow oil, 0.58 g.
containing 65% compound 85 and 35% of an unidenti-
- fied byproduct.
Example 11
BenzYl 7~-Azido-~3-0-2-isocephem-4-carboxylate
H H
N3 - ~ H H
2 DPSO
C02CH2Ph
88 - 89 ~02CH2Ph
To a solution of 260 mg. (0,64 mmole) of compound 88
-180-
Z52
ln 2.5 mi. of tetrahydrofuran was added 2.55 ml. of 0.25 M
80dium hydroxide solution dropwise over 10 minutes. The
solution was concentrated to 2 ml. on the rotary evaporator.
The concentrate wa~ washed with chloroform (2 x 2 ml.),
then evaporated to dryness under high vacuum. The residue
was stirred with one ml, of dimethyl sulfoxide for one hour.
Water (1 ml.), saturated sodium chloride (l ml.) and one
drop of 10% hydrochloric acid were added. The mixture
wa~ extracted wlth chloroform (3 x 2 ml.) and the combined
chloroform layers were washed with water and evaporated
to give crude compound 89 as a yellow solid, 103 mg. (54%
yield). The IR and NMR were consistent with the assigned
structure. The NMR indicated the product was about 757.
pure (i.e. true yield of 40%).
.
Example 12
7~-Phenoxyacetamido-3-carbomethoxymethyl~ne-~ 3-0-2-
_ocephem-4-carboxylic acid
, .
H H
,e~OCH2CO
l
N ~ CH2Co2cH3
93 C02H
-181-
_. ._ . . _ _,
~ Z5 2
H H
H2CONH -- -- H H
OCH2CC)NH~
CH3 ~ ~ CH2C02H
go C2C~2~ 91
--- ~' C02CH
Apparatu3 consist~ng of a 250 ml. three necked flask
equipped with a low temperature therometer, a gas inlet,
protected with a gas bubbler (parrafin oil) and magnetic
stirring, was dried by heating with a bunsen torch while
pa~sing dry nitrogen through the apparatus. It was allowed
to cool to 25C. before being opened, under nitrogen flow,
to introduce the reagents~
A solution of benzyl 7-3-~aminophenoxyacetoyl]-3-
methyI-/~3-0-2-isocephem-4-carboxylate 90 (2.11 g.; 5 mmole)
in 100 ~1, of THFl was cooled to -70 under a slow nitrogen
stream. A solution of 1.66 M butyl lithium2 (6.34 ml.;
10.5 mmole) was slowly added keeping the reaction tempera-
ture at -70C. A slow stream o~ dry carbon d~oxide gas
was then introduced into the reaction mixture, the cooling
bath was removed, and the carbon dioxide introduction con-
tinued until the reaction temperature reached 25.
The reaction mixture was poured into 200 ml. of 10%
hydrochlorlc acid, saturated with sodium chloride, and
extracted three times with diethylether ~150 ml. portions).
-182-
Z5Z
The combined extracts were washed three times with brine,
tried (anhydrous sodium sulfate) and evaporated in vacuo
to gi~e 2.09 g. of a yellow gum. Th~s gum was partitioned
between diethylether and 10% sodium bicarbonate solution
three times. The bicar~onate solutions were then washed
with diethylether (twice; 50 ml. portions) and with
methylene chloride (twice; 50 ml. portions). The bicar-
bonate solution was then acidified to pH2 with concen-
trated hydrochloric acid and extracted three times with
methylene chloride (100 ml. portions). The methylene
chloride extracts were washed twice with brine, dried
(anhydrous sodium sulfate), and evaporated in vacuo to
give 0.31 g. of a colorless gum. This gum was used as-
such in the next step.
l. The THF used was reagent grade which had been further
dried by passing over an alum~na column.
2. Foote Mineral Company
dOCH2CO~ 0OCH2CONH H H
I I > \ ~o
91 C2CH20 ~ ~ H2COzCH3
A ~olution of diazomethane in diethyletherl was slowly
added to a solution of ben~yl 7-B-~aminophenoxyacetoyl]-3-
carboxymethylene-~3-0-2-isocephem-4-carboxylate 91 (0.88 g.)
in 100 ml. of diethylether, until a permanent yellow color
- -183-
~ ~r~;Z~ .
(excess diazomethane) was produced. The reaction mixture
was then stirred at room temperature for 10 minutes. The
reaction was acidified with 10% hydrochloric acld and
extracted twice with 100 ml. por~ions of diethyle~her.
The extract wa3 washed with 10% sodium bicarbonate solut~on
(Swice; 75 ml. portions), with brine (once; 100 ml.), dried
(anhydrous sodium sulfate), and evaporated in vacuo to give
0.72 g. of activity III silica and then dry column chroma-
tographed over 36 g. of activity III silica gel. Elution
with chloroform gave a fraction containing 240 mg of
methyl ester 92 NMR and IR spectra are in agr-ement with
the assigned structure. This material wa~ used as such
$n the next step.
1. Prepared from nitrosomethylurea according t:o A.I. Vogel,
'~ractical Organic Chemistry", 3rd Edn., Lnngmans &
Green Co., London, 1958, p. 969.
H H H H
,00CH2CO~ 0OCH2CO~ .
CH2C02CH3 o ~ ,1
92 CO2CH2~ 93 ~ CH2CO2CH3
~ C02H
A mixture of benzyl 7-3-[aminophenoxyacetoyl~-3-carbo-
methylene-~3-0-2-isocephem-4-carboxylate ~ 147 mg.), 10%
Pd-C, (100 ~g.)~ 25 ml. of ethanol (USP) and 15 ml. of THF
-184-
Z5Z
was hydrogenated in a Parr hydrogenator at 17 psig for
1 hour. The catalyst was filtered off and the filtrate
evsporated to dryness _ vacuo to give 87 mg. of a white
foam.
The potassium salt of acid 93 waY prepared by d$ssolving
the foam in a small amount of methylisobutylketone and
adding 8 saturated solution of potassium 2-ethylhexanoate
~n butanol, The resultant precipitate was filtered off
and washed with methylisobutylketone and then diethylether.
M.P. 139-145C. with decomposition (cor.), Spectral data
confirm structure assignment.
Anal.C~lc'd.for ClgH17KN20g~1/2H20: C, 49.42; H, 4.15;
N, 6.40.
; Found: C, 49.05; H, 4.07;
N, 6.29.
A sample of compound 93 prepared above (called BC-L33)
after solution in water and dilution with Nutrient Broth
wss found to exhibit the following Minimum Inhibitory
Concentrations ~M.I.C.) in mcg./ml. versus the indicated
microorganisms as determined by overnight incubation st
37C. by tube dilution. Cephalexin was included as a
comparison compount.
.
-185-
i~ 252
Table 6
M.I.C. in mc~ /ml.
Or~anism BC-L33 Cepha-
lexin
D. pneumoniae A9585.06 .16
~5% serum* ,~
Str. pyogenes A9604.06 .16
5% serum*
S. aureus Smith ~ A9537.25 .6
S. aureus Smith $ A9537 1 1.3
~50% cerum
S. aureu3 BX1633-2 A960616 2
at 10- dil'n
S. aureu~ BX1633-2 A9606~125 4
at 10 dil'n
S. aureus meth.- A15097>125 32
- resist; at 10-3
dil'n
Sal. enteritidis ~ A9531 8 1 --
E. coli Juhl $ A15119 125 4
E. coli ~ A9675~125 16
K. pneumoniae ~ A997763 2
K. pneumoniae ~ A15130~125 8
Pr. mirabilis ~ A990032 2
Pr. morganii ~ A15153>125 >125
P8. aeruginosa $ Ag843A ~125 >125
Ser. marcescens ~ A20019>125 >125
Ent. cloacae A9656>125 >125
Ent. cloacae A9657>125 2
Ent. cloacae A9659>125 >125
* 50% Nutrient Broth - 45% Antibiotic Assay Broth
at 10-4 dilution.
-186-
.
252
Example 13
Separation of Diastereomers of
d-CH-CONH , ,
2 ~
~CH3
. C02H
The N-protected benzyl ester (1.3 g,) of the formula
H-CONH ~ 0
'NH l N I
0CH202~ ~ ~CH3
co2CH20
was placed on a sil~ca gel column (340 g. of silica gel -
15% water) and eluted with ether/petroleum ether (30-60
boiling) 70:30 ratio. Initial fractions consisted entirely
of one isomer designated "isomer A",`intermedlate fractions
were mixtures of isomer A and the other ~somer designated
"isomer B", and later fractions (212 mg.) contained 75-80%
ifiomer B and 20-25% isomer A.
A solution of the isomer B concentrate (t50 mg,) in
10 ml. of ethyl acetaté plus lO ml. of 95% etllanol was
treated with exactly one equivalent (0.26 ml.) of lN HCl.
To this solution was added 150 mg, of 30% palladium-on-
diatomaceous earth and the mixture was hydrogenated at
r~om temperature and atmospheric pressure until uptake of
-187-
ZSZ
hydrogen ceased. The c~talyst was removed by filtration
and the solvent evaporated to give 7B-(a-amino-~-phenyl-
acetàmito)-3-methyl-/\3-0-2-isocephem-4-carboxylic acid
(75-80% isomer B, 20-25% i~omer A) with 1/4 to 1 mole
ethanol and 1 to 2 moles H2O of crystallization per mole -
of acid. Any attempts at purification led to degradation.
H20
The product had U.V. ~Max 270 ( - 7850). The B isomer
was found to be the biologically active isomer.
M.I.C. data for the above product (called BC-L45)
~8 8hown in Table 7.
-188-
SZ
.
Table 7
. .
M.I.C. in mc~./ml.
Or~anism BC-L45 Cepha-
lexin
D. pneumoniae A9585 ~.25 .13
t5% serum*
Str. pyogenes A9604 ~.25 .13
+5% serum*
S. aureus Smith ~ A9537 1 .25
- S. aureus Smith ~ A9537 8
t50% serum
S. aureus BX1633-2 A9606 8
- at 10-3 dil'n
S. aureus BXl633-2 A9606 63 4
at 10-2 dil'n
S. aureus meth.- A15097 63 63
resist; at 10-3
dil'n
Sal. enteritidi~ ~ A9531 4 2
E. coli Juhl ~ A15119 4 8
E. coli ~ A9675 32 32
K. pneumoniae $ A9977 4 4
Y~. pneumoniae ~ A15130 8 16
Pr. mirabilis ~ A9900 8 4
Pr. morganii ~ A15153 63 >125
Ps. aeruginosa $ A98~-3A >125 >125
Ser. marcescens $ A20019 ~125 ~ 25
Ent. cloacae A9656 125 >125
Ent. cloacae A9657 4 4
Ent. cloacae A9659 125 >125
::.
* SO% Nutrient Broth - 45% Antibiotic Assay Broth
at 10-4 dilution.
-189-
ZS Z
Mouse Blood Le~el~ of BC-L45 and cephalexin after
oral administration of 100 mg./kg~, body weight are shown
below:
- Blood Levels ~g/ml)
0.5 1 2 3.5
Compound Hours after administration
BC-L45 19.4 15.7 7.3 2.9
Cephalexin 42.4 23.7 9.8 4.0
Example 14
7~-(D-~-aminophen~lacetamido)-~3-0-2-isocephem-4-
~arboxylic acid
H H
H-CONH ~-
. NH2.HCl rl I .
N ~
C02H
Benzyl 7B-azido-~\3-0-2-isocephem-4-carboxylate
(300.3 mg., 1 mmole) and 300 mg. 10% Pd/C in 40 ml. ethyl
scetate was shaken under H2 for 45 minutes at 6Q psi. The
suspension was filtered through celite and e~aporated to
--19 O--
L~}ZSZ
dryness. The IR spectrum of re~idue indicated complete
reduction of azido function to benzyl 7~-emino-~3-0-2-
isocephem-4-carboxylate.
The sbove-mentioned benzyl 7-amino intermediste was
dissolved in 25 ml. CH2C12 and t:reated with 285 mg.
(1 mmo~e) N-carbobenzoxy-D-phenyl glycine and 247.3 mB.
(1 mmole) EED~ for 2 hours. The solution was washed
w1th 10% HCl (2 x 30 ml.), saturated aqueous NaHCQ3 and
brine. The crude amide was chromstographed on silica
gel snd eluted with CH2C12. The IR snd NMR spectra
lndicated formation of the N-protected compound of the
formul~
~-CIH -CONH
}~C02CH20 ¦ I l
d~
co2CH2)~
A 8uspension of the above N-protected compound
~308.5 mg., 0.570 m~ole) snd 900 mg. 20% Pd (OH)2lC in a
m~xture of 40 ml. ethyl acetate and 1 ml. acetic acid
wa8 sha~en under H2 st 60 psi for 1 hour. The suspens~on
wa8 filtered through celite (filter cakes washed with
200 ml. CH2C12) snd evaporated to yield the free carboxylic
ac~d of the sbove N-protected ester.
V ~ EtOH 264, E- 5203
Max
Anal. Calc'd. for C22H21N307~1/2H20: C, 58.92; H, 4.97;
N, 9.37.
Found: C, ~9.12; H, 4.95;
N, 8~95.
.. . . . . , _ _ .
-191-
' ~
252
A 8uspension of 305 mg. (0.695 mmole) of tile above
free acit, 58 mg. anhydrous NaHC03 and 300 mg. 30% Pd/
d~atomaceous earth in 25 ml. H2O-15 ml. dioxane (pH 7-7.5)
was sgitated under H2at 60 p8i for 45 minutes. The
suspension was filte~ed ~filter cake washed with 50 ml.
X~BR and 10 ml. water) and filtrate was stirred for 20
minutes (pH 7.0). The organic layer was separated and
the pH of the aqueous layer adjusted to 3.75 with HCl.
The solvent was pumped under high vacuum (freeze-dried)
for 21.5 hours to give 200 mg. of the title product as
pale yellow powder.
U V ~ EtOH _ 261, - looo.
Max
A ssmple of the title product (called BC-L6) ~fter
601ution in water and dilution with Nutrient Broth was
found to exhlbit the following Mlnimum Inhibitory
Concentrations (M.I.C.) in mcg./ml. versus the indicated
microorganLsm~ as determined by overnight incubation at
37C. by tube dilution. Cephalexin was included a~ a
compariqon compound.
-192-
~L~l~Z52
,
able 8
~.I.C. in mc~./ml.
Or~anism BC-~6 Ce~ha
lexin
D. pneumoniae A9585 16 .3
~5Z serum*
Ser. pyogenes A96Q4 16 .3
-5% serum*
S. aureus Smith - A9537 32 1.3
S. auraus Smith - A9537 250 5
-50% serum
S. aureus BX1633-2 Ag606 125 4
at 10-3 dil 'n
S. aureus BX1633-2 A9606 500 8
2t 10-2 dil'n
S. aureus meth.- A15097~500 32
sesist; at 10-3
dil'rl
Sal. enteritidis - A9531 ~2 4
E. coli Juhl - A14119125 8
E. coli A9675 250 16
~ _
K. pne~moniae - A9977 63 4
K. pn~moniae - A15130125 16
Pr, mirabilis - A9900 125 4
Pr. morganii - A15153~500 >125
Ps. aeruginosa - A9843A>500 >125
Ser. marcescens - A20019~500 ~125
Ent. cloacae A9656
Ent. cloacae A9657
En~. cloacae A9659
-
* 50~ ~utrient Broth - 45Z Anti~iotic Assay Broth
- at 10-4 dilu~ion.
-193-
25Z
Example 15
7~-(2-Aminomethylphenvlacetamidol-3-meth~ -0-2-
isocephem-4-carboxylic acid
To a suspension of 1.2 g. (0.038 mole) of potassium 2-(1-
carbomethoxypropen-2-ylaminomethyl)phenylacetate in 23 ml. of
tetrahydrofuran was added 3 drops of dimethylbenzylamine. The
mixture was cooled in a dry ice bath to -40 and 520 mg. t0.038
mole) of isobutyl chloroformate was added all at once. The mix-
ture was stirred for 5 minutes and added to a cooled (3) solution
of 500 mg. of 7-amino-3-methyl- ~3-0-2-isocephem-4-carboxylic acid
and 0.71 ml. of N-methylmorpholine in 13 ml. of water. The solu-
tion was stirred in an ice-bath for 1 hour at 0, then concentrated
hydrochloric acid was added dropwise to pH 5.2. The tetrahydrofuran
was removed at 30 tl5 mm) and the aqueous solution was layered
, .
~, with ethyl acetate. The mixture was stirred at 25 for 1 hour and
- the crystals were collected, washed with water and dried over
P2O5 to constant weight to give 85 mg; mp >150 slow decomposition.
~- The NMR and IR spectra were consistent for the structure.
.~
Anal. Calc'd. for C17HlgN3O5.H2O
N, 11.56.
Found: C, 56.00; H, 5.68;
N, 11.32.
Example 16
7~-~-Benzoylureidophenylacetamido~-3-methyl- ~3-o-2-
isocephem-4-carboxylic acid
972 mg. tO.003 moles) of ~enzyl 7~-amino-3-methyl- ~3~
0-2-isocephem-4-carboxylate hydrochloride was partially
dissolved in 40 ml. of dry methylene chloride and 302 mg.
.
I -194-
!
ZSZ
I (0.003 moles) of N-methylmorpoli~e. To this was added 892 mg.
tO.003 moles) of ~-benzoylureidophenylacetic acid and 760 mg.
(0.003 moles) of EEDQ. The slurry was stirred for 30 minutes
at room temperature. Not all went in solution and 12 ml. of
N,N-dimethylformamide was added. A cloudy solution resulted
which turned clear after stirring for 30 minutes. The yellow
solution was stirred for 2 1/2 hours and was then concentrated
to an oil, which was redissolved in 80 ml. of ethyl acetate
and extracted with 80 ml. of 5% aqueous sodium bicarbonate and
80 ml. of 5% hydrochloric acid. The ethyl acetate phase was
dried over magnesium sulfate, filtered and concentrated to
dryness. The resulting foam was triturated with ether and the
resulting tan solid was removed by filtration and dried ln vacuo.
Wt = 700 mg. Infrared spectrum and NMR spectrum indicated
the solid to be benzyl 7~ benzoylureidophenylacetamido)-3-
methyl-~3-0-2-isocephem-4-carboxylate. This was dissolved
~i in 95 ml. of 100~ ethanol and 5 ml. of water at 39. 700 mg.
.
of 30% palladium on Celite was added. It was reduced at
50 lbs./sq. inch in a Parr hydrogenation apparatus for 30
minutes. The catalyst was removed by filtration through
Celite and it was washed with 100 ml. of 100% ethanol. The
combined filtrates were concentrated to an oil which was
solidified by slurrying it in ether. A tan solid resulted.
It was removed by filtration and dried in high vacuum.
Wt = 250 mg. Infrared spectrum and NMR spectrum were con-
sistent with the desired material.
Anal- Calc'd~ C24H22N47~4H2 C,
N, 10.20.
Found: C, 52.45; H, 4.26;
N, 10.22.
-195_
111~25Z
E~:â~ ~e 17
7B-~2.6-~imetho~-~benzamldo~-3-methvl-~3-0-2-
isoce~hem-4-c2rboxYlic 2c ~ d
729 ~g. (0.00225 moles) of benzyl 7-amlno-3-methyl-~3-
0-2-isocephem-4-carboxyLate hydrochloride wzs dissolved in
15 ml. of acetonierile and 453 mg. (0,0045 moles) of N-methyl-
morpholine. To this was added 420 mg. (0.00225 moles) of
2,6-dimethoxybenzoyl chloride. The yellow solution was
stirred for 2 hours at room temperature. A thin layer
ch~~matogram was taken at that polnt and it had one major
spot at Rf 0.6 indicating product. The reaction m~xture
was concent~ated to dryness, taken up in ethyl acetate
and extracted with 3Q ml. of 5% aqueous sodium bicarbonate
and 30 ml. of 5~/O hydrochloric acid. The ethyl~cetate phase
was dried over mzgnesium sulfate, filtered and concentrated
to a yell~w foam. It was solidified with ether, filtered
and dried in high vacuum for ~5 hours. A ean solid res-~lted,
wt ~ 500 mg. Infrared spectrum and NMR spectrllm indicated
it to be the desired benzyl 7~-(2,6-dimethoxybenzamido)-3-
methyl-~3-a-2-isocephem-4-carboxylate. This was dissolved
in 100 ml. of lOOZ ethanol at 40. A 907~ solution resulted.
To this was added 500 mg, of 30% palladiu~ on Cel-te. It
was reduced at 50 lbs./s~. inch in a Parr hydrogenation
apparatus for 40 minutes. The reaction mix~ure was heated
to 40- and the catalyst was re~oved by filtrztion through
~elite. I. was washed ~ice ~ieh 100 ml. of 100% ethanol
--19 ~
.. .. . . . .
- ~ 25Z
2nd the co~b~ned fil.rates we~e concent~a.ed to a g-eyish
' sol~d, which ~as washed with ether, filtered and drled
in vacuo, ~Jt - 350 mg. Infra~ed spect-~ and h~ spectrum
were consistent with the desired material.
Anal. Calc'd. for C17HlgN2O7-H2O: ~, 53.85; H, 5.27,
N, 7.38.
J Found: C, 54.77; H, 5.15;
~, 7.19.
Exam~le 18
~ -HYdrox~henYlacetamido)-3-methvl-~ -0-2-
isoce~em-4-carboxvlic acid
Benzyl 7~-amino-3-methyl-~3-0-2-isocephem-4-czrbaxy-
late hydrochloride ~972 mg., 0,003 moles) was dissolved
-
in 20 ml. of dry methylene chloride and 302 mg (0.003
;~
mo~es) or N-methylmorp'noline. To this was added 536 ~g.
(0.003 moles) of D-anhydro-o-carbaxy~and~lic acid. The
~ellow solution was stirred for 2 hours a~ room tempera-
ture. Then the reaction mix.ure was extracted with 20 ml.
of 5Z a~ueous sodium bicarbonate and 20 ml. of 5% hydro-
chloric acid. She me~hylene chloride phase waS d.ied over
m2gnesiu~ suifate, filtered and concentrated'to an oi'l.
It W2S triturated with ether. A yellow foam resulted,
wt = 550 mg. Tnfrared spe~trum and NMR spectru~ indicated
this to be desired benzyl 73-(~-a-hydroxyphenylacetamido)-
3-mee~,yl- ~3-0-2-isocephem 4-carboxyla~e. This waS
-197-
.
. ~. .
- -
lll~ZSZ
dissolved in 100 ml, ~f lOG/~ 2thanol and 550 mg. of 30%
~; palladiu~ on Cellte was added It was reduced at 5G lbs.
i 5q. inch in a P2rr hydrogenation apparatus for 30 minutes.
¦ The catalyst was removed by f ltr2tion through Celite and
was washed twice with 100 ml. of 100% ethanol. The
c~mbined filtrztes were concentrated to a greyish solid,
wh~ch was washed with ether, filtered and dried in vacuo,
, wt , 420 mg, Infrared spectru~ and NMR spectrum were
¦ consistent with the desired mater~al.
Anal. Calc'd. for C~6HL6N206-C2HsOH C~ 57-06;
~, 5.69; N, 7.41.
Found: C, 57.06;
H, 5.15; N, 6.93.
:~ .
~~ Exam~le 19
,
7B-~N-(PhenYlacetimido~l~aminoacetamidol-3-methYl-~3-
0-2-isoce~hem-4-carboxyllc acid
~.. ~ ,
_ Method 1:
Benzyl 73-amino-3-methyl-~3-o-2-isocephe~-4-carboxyLate
hydrochloride (243 mg., 0.00075 ~oles) was dissolved in 10 ml.
of dry methylene chloride and 75 mg. (Q.00075 moles) of
~-methylmorpholine. To this was added 170 mg. (0.00075 moles)
~f 3-benzyl-1,2,4-oxadiazo}e-5-one-4-acetic acid and 190 sg.
(0.00075 moles) of EE3Q. It was stirred for 2 hours 2
room te~erature and then concentrated to an orange-Drs~
foam, It was taken up in 20 ml. of ethyl acetate and
. .
Z5Z
extrscted with 20 ml. of 5% aquecus sod~um bicarbonate and
20 ml. of 57O hydrochloric acid. The ethyl acetate phase
was dried over magnesi~m sulfate, filtered and concentrated
,.
to a browr. oil, wt - lO0 mg, In~rared s?ect~um 2nd NMR
spectrum indicated the desired benzyl 7B-(3-benzyl-1,2,4-
oxadiazole-5-one-4-acetam do)-3-methyl-~3-0-2-isocephem-4-
carboxylate.
Method 2
, ~
3-Benzyl-1,2,4-oxadiazole-5-o~e-4-acetic acid (1.0 g.,
0.00427 moies) was slurried in 12.5 ml. of dry methylene
chloride and hydrogen chloride gas was bubbled into the
reaction mixture for 2 minutes with cooling. The insoluble
-~
n~terial was filtered off and 1.15 g. (0.00553 moles) of
phosphorus pentachloride was added to the filtrate in small
portions. All went in solution. It was stirred for 15
hours at room temperature, The reaction mixture was con-
~'t~ centrated to dryness and the crystalline residue was
-~-
triturated with cyclohexane, filtered and dried in high-
vacu~m for 30 minutes Infrared spectru~ indicated this to
be desired 3-benzyl-1,2,4-oxadiazole-5-one-4-~cetyl chloride.
In the meantime, 243 mg. (0.00075 moles) of benzyl 7a-amino-
= ~ 3-meth~ 3-0-2-isocephem-4-carboxylate hydrochloride was
dissolved in 10 ml, of dry methylene chloride and 151 mg.
~0.0015 moles) of N-methylmorpholine. To this was added
188 mg. (0.00075 moles~ of 3-~enzyl-1,2,4-oxadiazole-5-one-
4-acetyl chloride, The sllghtly yelltw solution was stlrred
! -lSg-
252
for 2 hours at room temperature. Then it was extracted
with 10 ~1. of 5% sodium bicarbonate. 10 ml. of 5Z hydro-
chloric acid and 10 ml. saturated sodium chloride solution.
The methylene chloride phase was dried over magnesium
sulfate, fileered and concentrated to a yellow foam,
wt _ 130 mg. Infrared spectrum and NMR spectrum lndicated
thi~ to be desired benzyl 7~-(3-benzyl-1,2,4-oxadiazole-5-
one-4-acetamido)-3-methyl-~3-0-2-isocephem-4-carboxylate.
Benzyl 7~-(3-benzyl-1,2,4-oxadiazole-5-one-4-acetamido)-
3-methyl-~3-0-2-isocephem-4-carboxylate (200 mg.) was
dissolved in 100 ml. of 100% ethanol and 10 ml. of water
at 40, To this was added 200 mg. of 30% palladium on
Celite. It was hydrogenated in a Parr hydrogenation
spparatus at 30 lbs./sq. inch for 40 minutes. The catalyst
was removed by filtration through Celite and was washed
thoroughly with 100 ml. of lOOX ethanol. The combined
filtrates were concentrated to a brown oil, which was
solidlfied with ether, filtered and dried in hi~h vacuum.
A brownish solid resulted, wt _ 100 mg. Infrared spectrum
~nd NMR spectrum were cnnsistent with the desired material.
Ansl. Calc'd. for C18H20N4o5`~H2o C, 55.60; H~ 5.70;
N, 14.38. t
Found: C, 55.45; H, 5.63;
N, 14.18,
-200-
. _, _ , . . .. . .
i~ -
Z5Z
Example 20
7~-V leramido-3-methyl-~3-0-2-isocephem-4-carboxvIic acid
r Benzyl 7~-amino-3-methyl-~3-0-2-isocephem-4-carboxylate
hydrochloride (1.21 g., 0.00375 moles) was dissolved in 25 ml.
of dry methylene chloride and 375 mg. (0.00375 moles) of
N-methylmorpholine. To this was added 380 mg. (0.00375 moles)
of valeric acid and 950 mg. (0.00375 moles) of EEDQ. The
slightly yellow solution was stirred for 2 hours at room
temperature. Then the reaction mixture was washed with 50 ml.
of 5% aqueous sodium bicarbonate and 50 ml. of 5% hydrochloric
acid. The methylene chloride phase was dried over magnesium
~, sulfate, filtered and concentrated to a yellow oil, which was
washed with ether and dried in high vacuum. A yellow oil
resulted, wt = 602 mg. Infrared spectrum and NMR spectrum
indicated this to be the desired benzyl 7~-valeramido-3-methyl-
~3-0-2-isocephem-4-carboxylate. This was dissolved in 100 ml.
of 100% ethanol and 600 mg. of 30% palladium on Celite was
.,~ . . J
added. This was reduced at 40 lbs./sq. inch in a Parr hydro-
~ genation apparatus for 35 minutes. The catalyst was removed
- ' 20 by filtration~through Celite and washed thoroughly with lO0 ml.
of 100% ethanol. The combined filtrates were concentrated to
a brown oil, which was solidified by washing with ether. A
tan solid resulted. It was removed by filtration and dried
ln vacuo for 15 hours, wt = 310 mg. Infrared spectrum and
NMR spectrum were consistent with the desired material.
Anal- Calc'd- for C13H18N25 C, 55.50; H~ 6-44; N, 9-96-
Fowld: C, 55.3~, ~, 6.06i ~, 9.07.
- -201-
~1Q'~5Z
~xample 21
C6H50CH2NHCONH
., ~0
~ H3
C02H
- A mixture of benzyl 7~-amino-3-methyl-~3-0-2-isocephem-
4-carboxylate (1.44 g.; 5 mmole) and phenoxyacetylazidel
(1.0 g,; 5.5 mmole) in benzene (100 ml. ) was refluxed for
24 hours. After being kept at room temperature for 3 days,
w me white crystals separated and were collected by suction
filtration; 0.30 g. white sol~d m.p. 195-196 with decompo-
8ition wa5 obtained. The filtrate was washed with lOZ
HCl, water and brine and then dried (~a2S04) and evaporated
to give 1.73 g. of a brown oil. Spectral data were in
accordance with the structure
0OCH2NHCONH
. rl l
~- ~ N~
COOCH2~
1. Joseph Weinstock, J. Org. Chem. 26J 3511(1961).
A solution of the above isocephem compound ~1.73 g.;
4,0 mmole) in absolute alcohol (25 ml.) and tetrahydrofuran
(lO ml.) was added to 10% Pd on C (1.7 g.) and stirred under
hydrogen at atmospheric pressure for 2 hours. The solution
-202-
_, _ . . . _ .. . .
!Z52
~as filtered from the catalyst through celite and evapor-
ated to give 1.03 g. oil. This was partitioned between
ether and saturated NaHC03. The aqueous phase was separ-
ated, acidified with cold 10% HCl, and ex~racted with
CH2C12. The CH2C12 extract was washed with water, and
brine, dried (Na2S04) and evaporated to give 0.20 g.
brown semi-solid. This was crystallized in benzene/
petroleum ether (30-60) and gave a light yellow shiny
801id identified by spectral analysis as the compound of
the formula
,0'0CH2NHCONH
' ~r~o
~ N ~
C02H
M~P. 177-182 with decomposition.
Anal Calc'd. for C16H17N306 1/4 H20: C, 54.62; H, 5.01;
N, 11.94.
Fo~nd: C, 54.59; H, 4.96;
N, 11.46.
M.I.C. data for the above product (called (BC-~24) is
~hown in Table 9.
-203-
. . ~
Z5Z -) ~
J i
Exam21e 22
73-~.en~lace~2mido-3-~ethyl- ~ ~0-2-isoc~em-4-
car~ox~l c acld
,
,~:H2CONH
, ~
CH3
C02H
A m~xture of benzyl 7,~-amino-3-methyl-~3-0-2-isocephem-
4-carboxylate (2.1 g.; 7.3 mmole), phenylacetic acid (L.0 g.;
1.3 ~ole) and EEDQ (1.8 g.; 7.3 mmole) in 5~ ml. CH2C12
was stirred at room temper~ture for 2 hours, then washed
.-
successively with lZ Na'~C03, lO~o HCl and brine. It was
dried (Na2S04) and evaporated to give 2.95 g. of a thic~
-~yrup identified as benzyl 7~-phenylacetamido-3-methyl~
0-2-isocephem-4-carboxylate. This ester was ~sed as such
with no fur~her purification.
A mixture of the above benzyl ester (O.S0 g.; 1.2
mmole) and 107~ Pd on C t0.50 g.) in T~F ~20 ml.~ was hydro-
gena~ed at atmospheric pressure and after 10 ~inutes,
uptake or hydrogen was complete. It was filtered (washed
well with CH2C12) and evaporated to giY~ 0.29 g. of a
solid. This was recrystallized from acetone/ether to
give a white solid, m.p, 197-198 with decomposition,
which was identified by IR and NMR as the title product.
Anal Calc'd. for C16H16N20s-1.5H~Q: C, 55,97; H, 5,57;
N, 7.15.
Found: C, 55,83; H, 5.85;
~, 7.17.
.I.C. dâta ~o t.~e ~bove product (called BC-L3Q~
i8 sho~n in LaDle g.
-2~4-
UZ5Z
Example 23
~ -3-methyl-~3-0-2-isocephem-
4-carboxylic acid
~CONN~f o
H3
COOH
Benzyl 7~-azido-3-methyl-~3-0-2-isocephem-4-carboxy-
late (314 mg.; 1 mmole) in 50 ml. of absolute ethanol was
hydrogenated at 40 psi of hydrogen in the presence of
palladium chloride (100 mg.) for 1 hour. The palladium
black was filtered off and the solvent was removed on a
~lash evaporator leaving a crude hydrochloride salt -of
7~-amino-3-methyl-~ -0-2-isocephem-4-carboxylic acid
(234 mg.).
.
; This crude hyclrochloride salt was dissolved in 5 ml.
of water and cooled to 0C. in ice bath. Sodium bicarbon-
ate (500 mg.; 6 mmole) was added followed by 2-thienyl
acetyl chloride (320 mg.; 2 mmole) in 2 ml. of acetone.
The mixture was stirred for 1 hour and then extracted
twlce with diethylether (10 ml. portions). The aqueous
layer was acldified with hydrochloric acid (aqueous 10%)
and extracted three times with chloroform (10 ml. portions).
The comblned chloroform extracts were concentrated to a
re8idual oil on an evaporator. A solid was obtained upon
-205-
~_ . ._.
Z5Z.
triturati.on with diethy^ether and was recrystallized fro~
ethanol eo give 160 mg. (50Z) of the title product; m.p.
213C. (corrected).
U.V. ~ _ 270; - 9187
max . - -
An~l. Calc~d. for C14H14N2O5S C, 52-17; H~ 4-38;
N, 8.69; S, 9.95.
Found: C, 51.89; H, 4.59;
N, 8.6i; S, 9.78.
M.l.C. data for the above product (called BC-L5S) is
8hown in Table 9.
-206-
_, . _ . .. .
1~ 252
J
Exam~le 2 4
7B- r~-carboxv-~-~henYlace_am.ido !-3-r~.eth~ l- ~3-o-2-
isoce~hem-4-carboxYlic acid
0~ `
. N~lCH3
: . C02H
l ~CH2C02H ~CH20H, H ~ ~CH2C02c~2~
.~ ~
;; A solution of phenyl acetic acid (27.2 g.), benzyl
alcohol (21.6 g.) and p toluenesulfonic acid (380 mg.) in
~ 10~ ml. af toluene was heated under refl~Y under a Dean-
- ~ Stark trap until the theoretical (3.6 ml.) quantity of
water had been collected. On cooling, the solution was
washed with dilute NaHC03 and saturated NaCl and solv~nt
m~ wa8 removed ln vacuo... The resulting oil was distilled
- _.
at ~25-129 (0.4 torr)l to give pure benzyl phenylacetaee,
37.7 g. ~83~ yield).
02CH2~ 1. L~ICA ~CHC02H
2. C02 C02CH2~
A solution of 20.8 ml. of 2.4 M n-butyl lithium in
hexane was added to a solution of i-propylcyclohexylamine
(7.06 g.) ln 35 ml, of tetrahydrofuran ae -78. After 10
mlnutes, a solution of phenylacetic acid benzyl ester
111~252 -
(1~.3 g.) in 55 ml, of tetrahydrofuran was added over lO
m~nutes. After 5 minutes, carbon dioxide was bubbled
into the solution until the yellow color faded After
warming to 0, dilute sodlum carbonate and ether were
added until all the solid returned to solution. The
aqueou~ lsyer was separated and the organic layer
extracted with more dilute sodium carbonate. The combined
aqueous layers were washed with ether, cooled to 0 and
acidified with cold 3N hydrochloric acid. The aqueous
W88 extracted with ether (2 X 100 ml.) and the ether
washed with saturated sodium chloride, dried (sodium
sulfate) and evaporated in vacuo to give the desired
acid as an oil, 7.8 g., 58% yield. The acid has been
reported ~n the literature: Chem. Abs. 63, 13269 g (i965).
, . .
." H22~
P~HCO2H EEDO >
CH3 CO2CH2~
co2CH20
(A) (B)
~H-CONH
cO2CH20\~a
d~ N~I` CH3
~C) CO2CH2~
-- A solution of one millimole each of A, B
-208-
.
~ 25 2
I and EED~ in 8 ml. of methylenP chlo ide was ~.ainta.ned at
24~ for i6 hours, The resulting sGlution was washed with
2% sodium bi~arbonat2 (8 ml,), 10% hydsochloric acid (2 x
8 ~1.) and sa~urated sodium chloride (8 ml.), then dr~ed
. (sod'um sulfate) and ab~orbed onto 2 g. of grade m silica
gel.
The crude product, absorbed onto silica gel, was
. .
washed with methylene c~lor~de (10 ml.), then extracted
from the silica gel with ethyl acetate (100 ml.). The
,. .:b
; e~.racts were absorbed onto 1.7 g.-of silica gel and
` placed on an 11 g. column of silica gel (grade III). Elu_ion
w~th ether/hexane 75:25 gave pure (C) as the major fraction
-;'~* (307O yield). Recrystallization from ether~methylene
H: chloride gave material with m.p. 152-157 (with decomposi-
tion).
...
., Anal. Calc'd, for C3lH2gN207: C, 68,88; H, 5.22; N, 5.18.
. Found: C, 68.50; H, 5.38; N, S.l9.
~C~-CONH
C02C~20 ~ ~2/Pd
H3
' (C) C02C~20
~-CH-CO~H
~02H \~
~ ~ H3
(D) COOH
To a soluti3n ~f (C) t ~0 ~g.) in 10 ml. of ethan~l
l~lQZSZ - ~
plu8 10 ml. of ethyl acetate was added 100 mg, of 30%
pallsdium on diatomaceous earth. The resulting mixture
was hydrogenated at atmospheric pressure and 24 until
uptake of hydrogen ceased. The catalyst was removed by
filtration and the solvent evaporated to give the title
product (D) in quantitative yield, Attempts to crystallize
the crude product led to loss of purity.
V ~ MeOH 269 ( ~ 8800)
max
Anal Calc'd. for Cl7Hl6N2o7~c2H6o~ll2H2o C~ 54-94;
H, 5.38; N, 6.74.
Found: C, 54.90;
N, 5,28; N, 6.91.
M.I.C. data for the above product (called BC-L48) i9
shown in TablF 9.
.
-210-
;ZSZ
Example 25
7~-(o-Hydroxyphenylacetamido)-3-methyl-~3-0-2-
isocephem-4-carboxylic acid
OH
~CH2CON~
N ~ CH3
C02H
The acylation procedure of Example 24 was re-
peated with the acylating acid used therein replaced by an
equimolar weight of o-hydroxyphenylacetic acid. The crude
acylation product, absorbed onto silica gel, was placed
on a column of silica gel (grade III, 8 g.). Elution with
ether gave, as the major fraction, benzyl 7~-(o-hydroxy-
; 10 phenylacetamido)-3-methyl- ~3-0-2-isocephem-4-carboxylate
in 26.5~ yield. The benzyl ester was hydrogenated as in
Example 24 to give the title product.
MeOH
U.V. ~ 274 (~ = 7200).
max
Anal- Calc'd- for C16H16N26 1/4H2 C, 57-06;
H, 4.94; N, 8.32.
Found: C, 56.92,
H, 5.03; N, 8.33.
M.I.C. data for the above product (called BC-L49)
is shown in Table 9.
- 211 -
Z f
Example 26
7E~-~CYanoacPtamido~-3-methyl- ~3-0-2-isocephem_4-
.
casboxYlic acid
.. . , -
~ NSCCH2CONH~
: ~ H3
., , C02H
The acylation procedure of Example 24 was repeated
w~th the acylating acid used therein replaced by an equi-
~olar weight of cyanoacetic acid. The crude acylation
product, absorbed onto silica gel, was placed on a column
, .
of silica gel (grade III, 3.5 g.) and eluted with ether,
methylene chloride and ethyl acetate. ~he methylene
~ chloride and ethyl acetate fractions were com~ined and
-~ triturated with chlorofQrm several times to give benzyl
~.: ,
7B-~cyanoacetamido)-3-methyl-~3-0-2-isocephem-4-
carboxylate in 31% yield. The benzyl ester was hydso-
genated as in Example 24 to give the title product.
MeOH
U.V. ~ 269 (~ - 6400)
, max
Anal. Cal'd. for CllHllN3O5~1/4~2O: C, 48.98; H, 4.30;
N, 15.58.
Found: C, 49.34, H, 4.42;
N, 15.41.
M.I.C. data for the above product (called BC-~50) is
~hcvn iD Table 9,
-212-
252
.~ If ~he procedure of Example 26 is repeated using a-cyanopropionic acid in place of the cyanoacetic acid
used therein, these is obtained 7~-(a-cyanopropionamido)-
¦ 3-methyl-~3-0-2-isocephem-4-carboxylic acid.
Example 27
7B-12-~2~-tetrazolylacetamido1-3-methyl- ~3-0-2-
,lsocephem-4-carboxylic acid
~ N - N
_ ' ~ ~C-CH2CONH~
.^ 10 ~ ~ H3
`
CH2C02Et Z H~ ~ CH2C02H'~20
~` H H
' A solution of potassium hydroxide (4,5 ~.) in 70 ml,
_ . of absolute'ethanol was added to a solution of the above
ethyl ester (5.0 g.) in 25 ml. of absolute ethanol
_ After heating under reflux for 30 minutes, the solution
: ' was eva~porated to dryness ~n vac~o. The residue was
di,~solved in 50 ml. water and a slurry t52 ml.) of ion
exchange resin (Dowex 50W-X4-acid form) was added. After
brief stirring, the resin was filtered off, the solu~ion
*Trade Mark
-213-
_
- - -
lll~Z5Z
treatet w~th charcoal, flltered and evaporated in vacuo
to give the acid indicated above as a crystalline solid,
3.68 g, (79% yield); m.p. 156-158C. CWith decomposition),
1, W. G, Finnegan, R. A. Henry, R. LofquLst, J. Am.
Chem Soc. 80, 3908 (1958)
The-acylation procedure of Example 24 was repéated
.
- with the acylating acid used therein replaced by an e~ui-
, molar weight of 2-(2H)-tetrazoleacetic acid and acetonitrile
~.................................................................. . .
- used as the solvent. The crude acylation product was
, crystallized from et~yl acetate to give pure ber~zyl 7B-~2-
-- (2H)-tetrazolylacetamido]-3-methyl-~3-0-2-isocephem-4-
~- casboxylate in 4~% yield; m.p. 169-170~ (with decomposition).
Ansl. Calc'd. for ClgHlgN605: C, 54.28; H, 4.55; N, 21.10,
-~ Found: C, 54.37; H, 4.75; N, 20.48.
..,~
- The mother ~iquors from the crystallization of the
.~
above benzyl ester were placed on a 3.5 g. silica gel (grade III
column, EIution with ether/ethyl acetate ~ave benzyl 7B-
~ (ethoxycsrboxamido)-3-methyl-~3-0-2-isocephem-4-carboxylate
-- ~n 21,5% yield which was used in the followlng example,
The benzyl 7~-[2-(2H)-tetrazolylacetamido~-3-methyl- ~ -
0-2-isocephem-4-csrboxylate was hydrogenated as in Example
24 to give the title product;
U.V.~ MexH 2tO (~ 9200),
Anal. Calc'd ~or CllHl2N6s~C2x6-l/2Hz C~ 42-97;
H, 5.27; N, 23,13.
Found: C, 42,99;
~, 4.58; N, 23.08.
M,I,C. data for the sbove product (called BC-L51)
i8 sh~wn in Table 9.
- -214
- -
- l~L1~252
Example 28
~ Ethoxycar~oxamido)-3-methyl-~3-0-2-isocephem-
4-carboxYlic acid
. . .
,~ CH3C~20CNH~ o
. ~ C~3
.C02H
Benzyl 7~-(ethoxycarboxamido)-3-methyl-~3-0-2-
. .,
. ~ isoc~phem-4-carboxylate (as produced in Example 37) was
hydrogenated as in Example 24 to give the title product.
U.V. ~ MaX~ 26g (E 7600).
:
~ Anal Calc~d. for CllH14N206~1t4C2t~60~1/4H20: C, 48.25;
: .~
~ H, 5.63; N, 9.79.
::~. Found: C, 47.g5;
-:~,~
,.. '.b,~ H, 5.12; N, 9.92.
. ~ M.I.C. data or the above product (called BC-L52) is
8hown in Table 9.
,
-215-
,
.
l~ Z52
Exam21e '~
''
7B-~3-~o-chloro~hen~ 5-methyl-isox~zol-4-vlcarbox-
zmido7-3-methvl-~3-0-2-1soce~hem-4-ca~boxYlic acid
:
~Cb3
CO2R
To a solution of 1.~ mmole of benzyl 7~-amino-3-~ethyl-
~3-o-2- f socephem-4-carboxylic acid and 1.10 ml. triethylamine
~n 5 ml. methylene chloride was added a solution of 1.~0 mmole o~
3-(o-chlorophenyl)-5-methyl-4-isoxazole-carboxylic acid
chloride in 5 ml. methylene chloride. After 18 hours at
24C., the solution was diluted with 50 ml. methylene
chloride and washed with ~0 ml. each of saturated Na~l,
lOX HCl, saturated NaHC~3 and saturated NaCl. The methylene
chlorlde solutfon was dried ~sodi~m sulfate) and evaporated
in vacuo to a brown solid which was triturated ~ith e-her.
The solid c-ude acylation product waS dissolved in
methylene chloride and absorbed onto 25 g. silica gel (grade
III), The silica gel W2S e7u.ed ~ith methylene chloride, then
ethyl acetate. The ethyl aceta~e extract was triturated
w~t~ ether to give benzyl 7~-[3-(o-chlorophenyl)-5-~ethyl-
iaoxazol-4-yl-carboxamido]-3-mechyl- ~ -0-2-isocephem-4-
-216-
. .
Z52
¦ carboxylate in 80~5~/o yield; m,p. 100-110C (with decomposition).
¦ Hydrogenation of the benzyl est:er according to the procedu~e
of Example 24 gave the title product.
u.v. ~ ~a~H 271 ( . 9600) . - - -
An~l Calc'd for ClgH16ClN3O6 C2H2O ~2O: C, 52.34;
H,. 5.02; N, 8.72; Cl, 7.36
Found: C, 51.81;
H~ 4.54; N, 9.37; cl, 7.15.
Residue: 1.9S%
. M.I.C. data for the above product (called BC-L59) is
.,
shown in Table 9.
~ . , '.
~ . ,.
.
.
-217-
.
' ' Example 30 ~ 25 2
¦ ,7B-tl-(lH~-Tetrazolylacetamido~-3-meth~l- A -0-2-
18 ocephem-4-carboxylic acid
N - N
CH3
02H . .
- l-(lH)-Tetrazolylacetic acid (256 mg.~, 6.25 ml. of
benzene and i.25 ml. oxalyl chloride were stirred at 24
for 3 days. The starting acid was filtered off and evapor-
atlon of the solution gave l-(lH)-tetrazoleacetyl chloride
in 58Z yield. --
The acylation procedure of Example 29 ~as repeated
with the acylating acid chloride used therein replaced by
; an equimolar weight of l-(lH)-tetrazoleacetyl chloride.
Th~ solid,acylation product, i.e. benzyl 7~-[1-(lH)-
tetrazolylaceeamido~-3-methyl-~3-0-2-isocephem-4-carboxy-
late, was obtained in 22.5% yield.
~ ydrogenation of the benzyl ester according to the
procedure of Example 24 gives the title product,
-218-
.
~ 25Z - ~
T~ble_9
The Minimum Inhibitory CoTlcentrations (M.I.C.) of
several of the compounds prepared above were determined
~gains~ the indicated microorganisms by ehe tube dilution
~ssay procedure. The results are as fol~ows: -
M.I.C.__~mc~.tml.)
Compound S._aureus E. coli Sal.enteriti.dis D._~neumoniae
of Ex. No.A9537A15119 _ _ A9585
0.6 16 >2.5 0.08
~6 0.6 63 8 .3
;:~ 17 >125 >125 32 32
, 18 2 16 8
:~.......... 19 4 ~125 125 0.5
. 20 125 ~125 ~125 125
~ 21 32 ~125 >125 16
--~ 22 ~ 1 ~25 4 0.5
~ 23 I 32 2 0.25
.~ 24 16 125 32 4
0.5 >125 >125 0.25
26 4 125 125 0.5
27 ~125 >125 ~12S 125
. 28 125 >125 >125 32
: 29 ~8 >125 >125 8
, .:
'-
-219-
