Note: Descriptions are shown in the official language in which they were submitted.
' 107~688
This invention relates to certain cephalosporin analogues
; and to the preparation thereof.
According to the present invention there is provided a com-
pound of the formula:
- 5 Y
N ~ 0 ~
0 N~ H3
COX
(I)
(wherein A and B are each hydrogen or an amino-protecting group;
X is hydroxy or a carboxy-protecting group; and Y is hydrogen or
methoxy; provided that when A is hydrogen B cannot be hydrogen or
phenylglycyl). The compounds of the invention may be prepared
effectively by the alignment of reactions set out below or by
adapting suitable variations in the order of indivisual reactions.
So-called oxadethiacephalosporins and oxadethiapenicillins
have been described by Christensen et al (Journal of the American
Chemical Society, Volume 96, 7582 (1975)), and by Wolfe et al
(Canadian Journal of Chemistry, volume 52~ 3996 (1974)).
The amino-protecting group in the formula (I) can be acyl,
silyl, sulfenyl, or hydrocarbyl group or other amino-protecting
group containing up to 20 carbon atoms (including the correspon-
ding groups in the side chains of natural or synthetic penicillins
and cephalosporins).
The acyl groups for A and/or B in the formula (I) include
inorganic acyls such as carbonic acyl (e.g. alkoxycarbonyl,
aralkoxycarbonyl or aryloxycarbonyl), sulfuric acyl, phosphoric
acyl (e.g. dialkoxyphosphinyl, dialkoxythiophosphonyl or alkoxy-
aminophosphoroyl); and organic acyls such as alkanoyl, cycloalkan-
oyl, aralkanoyl, aroyl, alkylsulfonyl, arylsulfonyl or alkylphos-
,
, .
- 107~688
' `~phonyl. These groups can, where possible, be interrupted by a
hetero atom in their skeleton or can be unsaturated or substituted
by, for example, halogen (e.g. fluorine, chlorine or bromine), a
` nitrogen function (e.g. amino, hydrazino, azido, alkylamino, aryl-
amino, acylamino, alkylideneamino, acylimino, imino or nitro),
oxygen function (e.g. hydroxy, alkoxy, aralkoxy, aryloxy, acyloxy
or oxo), sulfur function (e.g. mercapto, alkylthio, aralkylthio,
arylthio, acylthio, thioxo, sulfo, sulfonyl, sulfinyl, alkoxysul-
fonyl or aryloxysulfinyl), carbon function (e.g. alkyl, alkenyl,
aralkyl, aryl, carboxy, carbalkoxy, carbamoyl, alkanoyl, aroyl,
aminoalkyl, aralkanoyl or cyano), or phosphorus function (e.g.
phospho or phosphoroyl). A and B can also be considered together
as forming a diacyl group of a polybasic acid (e.g. phthalyl,
pyridine-2,3-dicarbonyl, maleoyl or succinoyl).
The hydrocarbon groups which may be represented by A and/or
B can be easily removable aliphatic hydrocarbon groups containing
from 1 to 20 carbon atoms (e.g. alkyl, alkenyl, aralkyl or other
aliphatic hydrocarbon groups) or easily removable monocyclic aro-
matic hydrocarbon groups (e.g. phenyl or pyrimidyl). These groups
can, where possible, be interrupted by a hetero atom in the skele-
ton thereof or can be unsaturated or substituted by a substituent
(e.g. halogen or by nitrogen, oxygen, sulfur, carbon, or phosphor-
us functions). A and B can also be considered together as forming -
a divalent hydrocarbon group (e.g. alkylene, aralkylene, alkylidene,
aralkylidehe~ a-halo- or alkoxy-aralkylidene, diarylmethylidene br
cycloalkylidene), which can, where possible, be interrupted by a
hetero atom in the skeleton thereof or can be substituted by a
substituent cited above or can be unsaturated.
When group A is acyl and group B is a hydrocarbon group they
can be combined together with the nitrogen atom bound to position
1070688
` 7 of the cephem ring to form a cyclic group (e.g. a 4-oxo-3-imida-
zolidinyl ring).
The silyl (e.g. trialkylsilyl) and sulfeny~ (e.g. phenylsul-
fonyl or o-nitrophenylsulfenyl) groups which may be represented by
A and/or B are conventional amino protecting groups.
Representative acyl groups for A in the above formula (I)
include, when B is a hydrogen, the following groups:
1) Cl to C5 alkanoyl;
2) C2 to C5 haloalkanoyl;
3) azidoacetyl;
4) cyanoacetyl;
5) acyl groups of the formula:
Ar-CQQ'-C0-
in which Q and Q' are each hydrogen or methyl; and Ar is phenyl,
dihydrophenyl or a monocyclic heterocyclic aromatic group contain-
ing from l to 4 hetero atoms, and may optionally be substituted
by an inert group e.g. Cl to C3 alkyl or alkoxy, chlorine, bromine,
iodine, fluorine, trifluoromethyl, hydroxy, cyano, aminomethyl or
nitro;
6) acyl groups of the formula:
Ar-G-CQQ'-C0-
in which G is oxygen or sulfur; and Ar, Q and Q' are as defined
above;
7) acyl groups of the formula:
Ar-CHT-C0-
in which Ar is defined above; and T is i) amino, ammonio, amino
protected by conventional amino protecting groups [for example,
benzyloxycarbonyl, C2 to C4 alkoxycarbonyl, cyclopentyloxycarbonyl,
cyclohexyloxycarbonyl, benzhydryloxycarbonyl, cyclopropylmethoxy-
carbonyl, methanesulfonylethoxycarbonyl, triphenylmethyl, 2,2,2-
10706~38
trichloroethoxycarbonyl, guanidylcarbamoyl, optionally substitutedureido carbonyl, Cl to C5 alkanoyl, pyroncarbonyl, thiopyridonecar-
bonyl, pyridonecarbonyl, homo- or heterocyclic monocyclic aromatic
acyl (optionally substituted by hydroxy, Cl to C3 alkanoyloxy,
halogen, trifluoromethyl, Cl to C3 alkyl, Cl to C3 aminoalkyl or
Cl to C3 hydroxyalkyl)] or amino protected in the for~s of phthali-
mido or enamino derived from acetoacetates, acetylacetone, or
acetoacetamide, ii) hydroxy or Cl to C7 acyloxy; iii) carboxy or
C2 to C7 alkoxycarbonyl, indanyloxycarbonyl, phenoxycarbonyl; or
iv) azido, cyano, carbamoyl, alkoxysulfonyl, sulfo, a~inosulfonyl
or alkoxysulfonyl; or HT combined represent hydroxyimino or alkoxy-
imino;
8) C3 to C5 2-sydnon-3-alkanoyl;
9) (2- or 4-pyridon-1-yl)acetyl;
10) 5-aminoadipoyl, 5-aminoadipoyl protected at the amino by
Cl to C10 alkanoyl, Cl to C5 chloroalkanoyl or C2 to C10 alkoxy-
carbonyl; or 5-aminoadipoyl protected at the carboxy by benzhydryl,
2,2,2-trichloroethyl, trialkylsilyl,Cl to C6 alkyl, nitrobenzyl
or methoxybenzyl; and
11) acyl groups of the formula:
L-O-CO-
in which L is an easily removable optionally substituted Cl to C8
hydrocarbon group (e.g. 2,2,2-trichloroethyl, isobornyl, tertiary
butyl, l-methylcyclohexyl, 2-alkoxy-tertiary butyl, benzyl, p-
nitrobenzyl or p-methoxybenzyl).
Alternatively, A and B considered together can represent a
diacyl group derived from a polybasic C4 to C12 carboxylic acid,
Cl to C6 alkylidene or C7 to Cg arylmethylidene.
In the above, examples of Ar groups are furyl, thienyl,
pyrryl, oxazolyl, isoxazolyl, oxadiazolyl, oxatriazolyl, thiazolyl,
1070688
isothiazolyl, thiadiazolyl, thiatriazolyl, pyrazolyl, imidazolyl,
triazolyl, tetrazolyl, phenyl, pyridyl, pyrimidyl, pyrazinyl,
pyridazinyl, triazinyl and dihydrophenyl, each being optionally
substituted by halogen, Cl to C3 alkyl, hydrbxy, Cl to C3 alkoxy
or aminomethyl.
The carboxy-protecting group which may be shown by X can con-
tain up to 20 carbon atoms and can be an oxygen functlon such as,
for example, Cl to C8 alkoxy (e.g. methoxy, ethoxy or t-butoxy),
C7 to C20 aralkoxy (e.g. benzyloxy, methoxybenzyloxy, nitrobenzy-
loxy, diphenylmethoxy or trityloxy), mono- or di-cyclic aryloxy
(e.g. phenoxy or naphthyloxy), or organometaloxy (e.g. trimethyl-
stannyloxy or trimethylsilyloxy), Cl to C8 organic or inorganic~
acyloxy or metal oxy of groups I, II or III in the periodical
table (e.g. sodiooxy, potassiooxy or magnesiodioxy); or X may be
selected from sulfur functions such as those forming thiol ester,
thiocarboxy or like groups, nitrogen functions such as those
forming amides, hydrazides, azide or like groups, or X may be
selected from other carboxy-protecting groups. These groups can,
where possible, be interrupted by a hetero atom in their skeleton,
or can be unsaturated or substituted by a substituent such as
those referred to above (e.g. the nitrogen, oxygen, sulfur,
carbon or phosphorus functions referred to above or halogen).
Among carboxy-protecting groups X are those forming Cl to C5
haloalkyl esters, C2 to C10 acylalkyl esters, C2 to C8 alkoxy-
alkyl or aminoalkyl esters, C2 to C8 acyloxyalkyl esters,
C3 to C8 carbalkoxyalkyl esters, the phenyl ester, C7 to C20
Y , 2 10 ' 1 5 Yamide, imide with saccharin, imide with phthalimide, N,N'-diiso-
~ .
___ . --
1070688
- ` butylhydrazide, metal salts, Cl to C6 alkylamine salts, dicyclo-
hexylamine salts or analogues thereof containing from 2 to 15
carbon atoms, or groups equivalent in effect to these groups (in
the above, specified numbers of carbon atoms are for groups X).
S Antibacterially preferred carboxy-protecting groups X include
those which form acyloxymethyl esters, phenacyl esters, the benz-
aldoxim ester, the N,N-dimethylaminoethyl ester, alkali metal
salts, alkaline earth metal salts, acylated alkaline earth metal
salts, and other groups equivalent in effect to these groups.
Preferred carboxy-protecting groups X include benzhydryloxy, p-
nitrobenzyloxy, p-methoxybenzyloxy, 2,2,2-trichloroethoxy and
- alkali metal-oxy.
Y can be a hydrogen or methoxy.
The compounds of formula (I) have been found to be very effec-
tive as antibacterial compounds against many bacteria and aresuperior to the corresponding l-thia or natural cephalosporins.
The compounds can be used as bactericides for combatting bacterial
! infections in humans or other animals, or the decay of perishables.
For human use, the compounds can be administered at a dose of 0.1
to 5 g/day/man. Administration may orally or parenterally and
may be in the form of any conventional pharmaceutical formulation
types, and may be in admixture with suitable carriers if required.
The present invention includes a pharmaceutical or veterinary
formulation which comprises a compound of formula (I) formulated
for pharmaceutical or veterinary use and preferably in unit dosage
form (e.g. tablets, capsules, pills, a suspension or solution or a
powder).
The invention further provides a pharmaceutical or veterinary
composition which comprises a compound of formula (I) and a phar-
maceutically or veterinarily acceptable, respectively, diluent,
1070688
carrier or excipient. Such compositions may be in unit dosageform.
New process for the preparation of the compound (I) is illus-
trated in SCHEME I below. ~owever, it lS to be understood that
the positions of individual reactions can be altered where prefer-
red and possible. It will be appreciated that the compounds of
formulae (15) and (16) are also compounds of formula (I).
Among the reactions, the introduction of a propargyloxy
group at position 2 of the azetidine ring to form compound (8)
gives predominantly the 2,3-cix isomer (in the ratio of up to
about 2:1 or more) in contrast to the cases where the 3-amino
group is acylated where the reaction gives exclusively or predomi-
nantly the isomer having the 2,3-trans configuration leading to an ~
ineffective final product (16) having a 6~-hydrogen. In the -
present process, introduction of the propargyloxy group precedes
acylation of the amino group (when the acylation step is included).
Furthermore, among procedures for the introduction of a propargy-
loxy at position 2 of the azetidine ring to form a compound (8),
that using zinc chloride is superior to that using silver tetra-
fluoroborate from the view point of higher yields, or improvedratio of the desired isomer and inexpensive production.
The present invention includes a process for the preparation
of a compound of the formula:
A~ N
o ~ ~ ~ CH3
COX
(wherein A and B are each hydrogen or an amino-protecting group;
X is hydroxy or a carboxy-protecting group; and
Y is hydrogen or (methoxy)
1070688
-
which process comprises converting a compound of the formula:
H2N ~ CH
O N`c=c ~ 3
COX CH3
wherein Hal is halogen and X and Y are defined above ~
to produce the desired compound by means of a series of steps sub-
stantially as set out in SCHEME I; provided that the acylation
step is optional and is not employed when both A and B are hydro-
gen in the final end product and the deprotection steps is alsooptional and is not employed when X is a carboxy-protecting group
in the final end product; and also provided that the order of the
individual steps may be altered from SCHEME I where possible.
The invention includes within its scope the products of the
above defined process in so far as they have been made by that
process.
The present process from compounds (8) to (10) is somewhat
analogous to the method of Neyler et al (Journal of Chemical
~;~ Society, 1973, 57) of the Beecham Group and the present process
from compounds (12) to (15) is somewhat analogous to the method
of Neyler et at (Journal of Chemical Society, 1972, 229) of the
- Beecham Group; provided that the above listed references
relate to l-thia instead of l-oxacephalosporins. The step of
the present process from compounds (15) to (16) is a procedure
which is _ _ _
/
/
-- _
'"1 ~
.
10~7~)688
` H2N` ~ Ha HOCH2C--CH H2N \ ~ OCH C--CH
CH Or derivs.
O ~ ~ `C=C~ 3 Cl-trapping N ~C=C~ 3
3 reagent 3
(7) CoX (8) COX ;
A_ N OCH C-CH ~ \ OCH2COCH3 :-
Acylate B ~ 2 Hydrate I ~
~ ` T=C~CH O ~ N C=C~cH3
(9) COX (10) COX
.
A -N OCH2COCH3 -N ~ OCH2COCH3
: Oxidative ~ ~ Reduce ~ I : fission o ~ ~ IC=O O fHOH
(11) CoX (12) COX
B _N ~ OCH2COCH3 A ~ ~ OCH2COCH3
15 Naloqenation ~ N `CH H 1 7 O ~ N ~C=P'
(13) COX (14) COX
B _N . o ~ A~ N O
Wittig (2) ~ ~ Deprotect ¦ ~ ~
o ~d~ ~ H3 o ~ N ~ ~ ~ CH
(15) COX (16) COOH
SCHEME- I
conventional in the art.
One embodiment of the present invention is cephalosporins
analogue represented by formula (I) wherein A is phenylacetyl,
D-mandeloyl, a-phenylmalonyl~ D-a-(3-methanesulfonyl-2-oxo-imidazo-
lidin-l-yl)carbonamido-a-phenylacetyl, or 2-thienylacetamido; B is
hydrogen; X is hydroxy; and Y is hydrogen, and pharmaceutically
acceptable salts and esters thereof (such as the types of salts
..
107()688
-~ and esters outline above).
Among the said cephalosporin analogue, the compound represen-
ted by the following formula is a remarkable antibacterial:
C6H51CHCONH ~ ~
COOH O 1 3
COOH
in the forms of free acid, pharmaceutically acceptable salts and
; esters (especially diphenylmethyl esters).
The above specific compound, 7~-(a-carboxyphenylacetamido)-
3-methyl-1-oxadethia-3-cephem-4-carboxylic acid, shows when
assayed in vitro, strong antibacterial activity against gram nega-
tive bacteria even at higher inoculum size than 10 , and especially
against strains of Escherichia coli resistant to many penicillins
and cephalosporins. Its remarkable character is also demonstrated
by its strong activity against Enterobacteria to which almost all
penicillins and cephalosporins are inactive at a concentration of
100~/ml.
The above specific compound can be prepared by acylating 7-
: .
amino-3-methyl-1-oxadethia-3-cephem-4-carboxylic acid or its
esters with a reactive derivative of a-phenylmalonic acid, follow-
ed, if requiredJ by deprotection and purification according to
conventional methods.
The compound (I) wherein the acyl group represented by A or
B is phenylacetyl is superior to the corresponding l-thia compound,
i.e. 7-phenylacetamidodeacetoxycephalosporanic acid, especially in
its exceeding potency against typical gram negative bacteria.
The present invention includes a method for preventing or
inhibiting the growth of bacteria in an environment which compri-
ses administering to the environment an effective amount of a
107068~3
compound of formula (I) or of a formulation or composition inaccordance with the invention. The method may be used for the
treatment or prevention of infection in an animal, for the preven-
tion of decay in a perishable material or for the disinfection of
a substance, an article or a building structure.
The following description is given to provide an Example of
the preparation of the compounds (I) according to SCHEME I. In
the Example A`N- is phenylacetamido; X is diphenylmethoxy; Y is
hydrogen; and Aryl is phenyl. In the NMR data the Hz values in
parentheses are coupling constants.
The interconversion of some compounds (I) is also described
in the following Example, starting from compound (16).
DiPhenvlmethYl a-[2~ and 2a-chloro-3~-amino-4-oxoazetidin-1~
a-iso~ropylideneacetate (7) -
To a solution of crude diphenylmethyl a-(2~-methylthio-3~-
amino-4-oxoazetidin-1-yl)-a-isopropylideneacetate toluene-p-sul-
fonate salt (5)(13.48 g; 20 mmole) in methylene chloride (100 ml)
is added a solution of chlorine in carbon tetrachloride (1.34
Mole/liter; 19.4 ml; 36 mmole) at -78 C. The mixture is stirred
20 at -78 C- for 20 minutes and at 0 C for 20 minutes, and evaporated
.~ : . -. .
under reduced pressure. The residue is triturated thrice in a
mixture of ether and petroleum ether, and evaporated to give crude
diphenylmethyl a-[2~ and 2a-chloro-3~-amino-4-oxoazetidin-1-yl]-
a-isopropylideneacetate toluene-p-sulfonate salt (6) as yellow
25 foam (13.45 g).
The product is treated with aqueous solution of sodium hydro-
gen carbonate and extracted with dichloromethane to give crude
diphenylmethyl a-[2~ and 2a-chloro-3~-amino-4-oxoazetidin-1-yl]-
a-isopropylideneacetate (7) as yellow brown heavy syrup (9.50 g)
(From its NMR spectrum, the ratio of 2~ and 2a-chloro isomers was
11
' 1070688
~ estimated to be about 4:1). Separation of a part of the crude
product (2.50 g) by chromatography over silica gel containing 10%
water (100 g) gives from the fraction eluted with a mixture of
benzene and ethyl acetate 13:1), a (1:1) mixture of 2a and 2~-
chloro isomers (120 mg)j and pure 2~-chloro isomer (480 mg).
2a-chloro isomer:
~MR:~ 3 1.98s3H, 2.25s3H, 2.83br-s2H, 4.33d(1.2Hz)lH, 5.47d
(1.2Hz)lH, 6.90slH, 7.30slOH (Estimated from NMR of mixture).
2~-chloro isomer:
IR:~ CmHx 3 3425, 3370, 1787, 1730 cm
NMR:~ 3 1.98s3H, 2.25s3H, 2.80br-s2H, 4.50d(4.0Hz)lH, 5.87d
(4.0HzjlH, 6.90slH, 7.30slOH.
Diphenylmethyl a-~2~ and 2a-(2-propynyloxy)-3~-amino-4-oxoazeti-
din-l-Yl]-a-isopropylideneacetate (8)
1) To a solution of crude diphenylmethyl -[2~ and 2a-chloro-
3~-amino-4-oxoazetidin-1-yl]-a-isopropylideneacetate (7) (0.95 g)
in a mixture of propargyl alcohol (3 ml) and tetrahydrofuran (2 ml)
is added silver tetrafluoroborate (0.79 g; 4 mmole), and the mix-
ture is stirred at room temperature for 3 hours. The reaction
mixture is diluted with benzene (50 ml), cooled to 0 C, and stirred
with a mixture of 5% aqueous solution of sodium hydrogen carbonate
(10 ml) and saturated saline (5 ml). The mixture is filtrated
through a layeF of Celite* and filtrate is separated. The benzene
layer is dried over sodium sulfate, concentrated under reduced
pressure to give brown heavy oil, and purified by chromatography
over silica gel containing 10~/o water (50 g) gives 2a-propynyloxy
derivative (134 mg) and 2~-propynyloxy derivative (134 mg) from
fractions eluted with a mixture of benzene and ethyl acetate
(1: 1) . '
2a-propynyloxy isomer:
* Trade Mark 12
~ .
:,
1070688
`- IR:~ 3 3400, 3320, 2115, 1767, 1723 cm
NMR:S 3 1.83br-s2H, 1.9853H, 2.22s3H, 2.33t(2.5Hz)lH, 4.07d
(2.5Hz)2H, ca. 4.07dlH, 4.93d(1.0Hz)lH, 6.90slH, 7.32slOH.
2~-propynyloxy isomer:
IR:~ 3 3410, 3320, 2115, 1767, 1720 cm
NMR:,~ 3 1.77br-s2H, 2.00s3H, 2.23s3H, 2.27t(2.5Hz~lH, 4.12d
(2.5Hz)2~, 4.23d(4.0Hz)lH, 5.27d(4Hz)lH, 6.90slH, 7.32slOH.
2) To a solution of crude diphenylmethyl a-[2~ and 2a-
chloro-3~-amino-4-oxoazetidin-1-yl]-a-isopropylideneacetate (7)
(0.95 g) in propargyl alcohol (5 ml) is added fused zinc chloride
(818 mg; 6 mmole), and the mixture is stirred for 2 hours at room
temperature. The reaction mixture is diluted with benzene (50 ml)
cooled to 0 C, shaken with 5% aqueous sodium hydrogen carbonate
(30 ml), and stirred vigorously. The mixture is filtered through
a layer of Celite to remove separated solid, and the filtrate is
separated. The benzene layer is dried over sodium sulfate, and
evaporated under reduced pressure to leave brown heavy oil. Puri-
fication of the residue by chromatography over silica gel contain-
ing 10% water (50 g) gives starting material (107 mg), 2a-propynyl-
; 20 oxy isomer (106 mg), and 2~-propynyloxy isomer (213 mg) from the
fraction eluted with a mixture of benzene and ethyl acetate (1:1).
3) The reaction of above 1) and 2) can be carried out by
using sodium iodide, stannous chloride, and silver perchlorate in
place of zinc chloride or silver tetrafluoroborate.
Diphenylmethyl a-[2~-(2-propynyloxy)-3~-phenylacetamido-4-oxo-
azetidin-l-yll-a-isopropylideneacetate (9)
To a solution of diphenylmethyl a-[2~-(2-propynyloxy)-3~-
amino-4-oxoazetidin-1-yl]-a-isopropylideneacetate (8) (2.039 g;
5.04 mmole) in methylene chloride (15 ml) are added phenylacetyl
chloride (1.00 ml; 7.56 mmole) and pyridine (0.61 ml; 7.56 mmole)
13
~ 1070688
`--at 0 C with stirring. The mixture is stirred at 0 C for 30
minutes, mixed with ice water, and extracted with methylene chlor-
ide. The methylene chloride layer is washed with water, dried
over sodium sulfate, and evaporated under reduced pressure.
Purification of the residue by chromatography over silica gel
containing 10% water (100 g) using a mixture of benzene and ethyl
acetate (3:1) as eluting solvent gives the product (9) as pale
yellow foam (2.242 g; 85.1%).
;~ IR:Y 3 3425, 1680, 1510, 3310,2115, 1773, 1720 cm
NMR:~ 3 1.98s3H, 2.25s3H, 2.23t(2.5Hz)lH, 3.58s2H, 3.95d
- (2.5Hz)2H, 5.32-5.52m2H, 6.50d(LOHZ)lH, 7.00slH, 7.35-7.40ml5H.
Diphenylmethyl a-(2~-acetonyloxy-3~-phenylacetamido-4-oxoazetidin-
l-yl)-a-isopropylideneacetate (10)
; To a solution of diphenylmethyl a-[2~-(2-propynyloxy)-3~-
phenylacetamido-4-oxoazetidin-1-yl]-a-isopropylideneacetate (9)
(2.236 g; 4.28 mmole) in methanol (20 ml) is added water (2 ml.).
To this solution is added a saturated solution of mercuric sulfate
in 10~/o sulfuric acid (0.8 ml), and the mixture is refluxed for 30
minutes. The reaction mixture is cooled, diluted with ethyl ace-
tate, and washed with water. The ethyl acetate layer is driedover sodium sulfate, and concentrated under reduced pressure.
Purification of the residue by chromatography over silica gel con-
taining 10% water (100 g) using a mixture of benzene and ethyl
acetate ~2:1) as eluting solvent give the product (10) as pale
yellow foam (1.547 g; 66.9%).
IR:y 3 3425, 1676, 1510, 1774, 1735(shoulder), 1720 cm
NMR:~ 3 1.83s3H, 1.97s3H, 2.23s3H, 3.60s2H, 3.6Q+3.97q
(8Hz)2H, 5.03d(4Hz)lH, 5~27dd(4;8Hz)lH, 6.50d(8Hz)lH, 6.93slH,
7.30+7.33ml5H.
Diphenylmethyl ~-(2~-acetonyloxy-3~-phenylacetamido-4-oxoazetidin-
14
1070688
vl)qlyoxalate (11)
To a solution of diphenylmethyl a-(2~-acetonyloxy-3~-phenyl-
acetamido-4-oxoazetidin-1-yl)-a-isopropylideneacetate (10) (2.342
g; 4.33 mmole) in methylene chloride (40 ml) is introduced ozoni-
zed oxygen for 25 minutes at -78 C. Excess ozone is purged with
nitrogen gas, and the mixture is mixed with dimethyl sulfide (3 ml)
and stirred at -78C for 30 minutes, and at room temperature for
30 minutes. The reaction mixture is mixed with three drops of
acetic acid, washed with water, dried over sodium sulfate, and
evaporated under reduced pressure to give the product (11) as pale
yellow foam (2.312 g).
IR:~ 3 3420, 1680, 1507, 1822, 1733, 1707 cm
NMR:~ 3 1.87s3H, 3.55s2H, 5.30-5.57m2H, 6.85d(8Hz)lH, 4.22s2H,
6.93slH, 7.22+7.30ml5H.
DiPhenylmethyl a-(2~-acetonyloxy-3~-phenylacetamido-4-oxoazetidin-
l-vl)qlvcolate (12)
To a solution of diphenylmethyl a-(2~-acetonyloxy-3~-phenyl-
acetamido-4-oxoazetidin-1-yl)glyoxalate (11) (2.312g) in a mixture
of methylene chloride (10 ml) and glacial acetic acid (10 ml) is
added actlvated zinc powder (2.50 g) with stirring, and the mixture
is stirred for 3 hours at room temperature. The reaction mixture
is filtered through a layer of Celite which is washed with methy-
lene chloride. The filtrate is washed with water, dried over
sodium sulfate, and evaporated under reduced pressure to give the
product (12) as pale yellow foam (2.136 g) as a mixture of epimers
at position a.
IR:~ 3 3425, 1675, 1505, 3350, 1785, 1740 cm
DiphenYlmethyl a-(2~-acetonyloxy-3,~-phenylacetamido-4-oxoazetidln-
l-yl)-a-chloroacetate (13)
To a solution of diphenylmethyl a-(2~-acetonyloxy-3~-phenyl-
1070688
` acetamido-4-oxoazetidin-1-yl~glycolate (12) (2.136 g) in anhydrous
methylene chloride (20 ml) are added thionyl chloride (0.90 ml)
and pyridine (0.33 ml) with stirring at 0 C. After stirring for
1 hour at 0 C, the mixture is poured into ice water, and extracted
with ethyl acetate. The organic layer is washed with water, dried
over sodium sulfate, and evaporated under reduced pressure to give
the crude product (13) (2.251 g) as brown foam of a mlxture of
epimers at position a.
IR:y 3 3430, 1680, 1510, 1795, 1752, 1740(shoulder) cm
Diphenylmethyl a-(2~-acetonyloxy-3~-phenylacetamido-4-oxoazetidin-
l-yl)-a-triphenylphosphoranylideneacetate (14)
To a solution of crude diphenylmethyl a-(2~-acetonyloxy-3~-
phenylacetamido-4-oxoazetidin-1-yl)-a-chloroacetate (13) (2.251 g)
in anhydrous methylene-chloride (20 ml) is added triphenylphos-
phine (1.50 g), and the mixture is refluxed for 4 hours undernitrogen atmosphere. The reaction mixture is poured into ice
water, mixed with 5% aqueous solution of sodium hydrogen carbonate
(20 ml), and extracted with methylene chloride. The organic layer
is washed with water, dried over sodium sulfate, and evaporated
under reduced pressure. Purification of the residue by chromato-
graphy over silica gel containing lOo/o water (100 g) using a mix-
ture of benzene and ethyl acetate (1:2) as eluting solvent gives
the product (14) (2.328 g) as yellow foam.
IR:~ 3 3433, 1675, 1507, 1770, 1735, 1628 cm
Diphenylmethyl l-oxadethia-3-methyl-7-phenylacetàmido-3-cephem-
4-carboxylate (15)
A solution of diphenylmethyl a-(2~-acetonyloxy-3~-phenylace-
tamido-4-oxoazetidin-1-yl)-a-triphenylphosphoranylideneacetate
(14) (2.328 g) in anhydrous dioxane (30 ml) is refluxed for 64
hours under nitrogen atmosphere, and evaporated under reduced
16
1070688
pressure to remove dioxane. The residue is purified by chromatog-
raphy over silica gel containing 10% water (150 g) using a mixture
of benzene and ethyl acetate (1:1) as developing solvent to give
the product (15) (1.103 g; 74.7%). Crystallization of the product
from ether gives pure colorless crystals of compound (15).
m.p. 106-107C.
IR:y mHC 3 3428, 1679, 1510, 1792, 1721 cm
- NMR:~ 3 1.93s3H, 3.63s2H, 4.03s2H, 4.95d(4Hz)lH, 5.68dd
(4;9Hz)lH, 6.67d(9Hz)lH, 6.92slH, 7.33+7.38ml5H.
[a]D -62.7 + 1.9 (c=0.533, CHC13).
W: A m x 2 267-5 nm (=7760).
l-Oxadethia-3-methyl-7-phenylacetamido-3-cephem-4-carboxylic
acid (16)
To a solution of diphenylmethyl l-oxadethia-3-methyl-7-phenyl-
acetamido-3-cephem-4-carboxylate (15) (66 mg) in methylene chlor-
ide (3 ml) are added anisole (0.2 ml) and trifluoroacetic acid
(0.2 ml) with stirring at 0C, and the mixture is stirred at 0C
for 2 hours. The reaction mixture is concentrated under reduced
pressure to dryness, and the residue is dissolved in aqueous 5%
sodium hydrogen carbonate solution, and washed with ether. The
aqueous layer is acidified with 2N-hydrochloric acid, and is ex- -
tracted with ethyl acetate. The organic layer is washed with
w-ater, dried over sodium sulfate, and evaporated under reduced
pressure. Crystallization of the residue from a mixture of methyl-
ene chloride and petroleum ether gives the product (16) (30 mg)
as colorless crystals. m.p. 180-182 C (with decomposition).
IR:y 3404, 1778, 1650, 1536 cm
DiPhenylmethYl l-oxadethia-7-amino-3-methyl-3-cephem-4-carboxylate
(17)
To a solution of diphenylmethyl l-oxadethia-7-phenylacetamido-
1070688
` 3-methyl-3-cephem-4-carboxylate (15) (600 mg, 1.243 mmole) in
methylene chloride (15 ml) are added phosphorus pentachloride
(518 mg; 2.486 mmole) and pyridine (0.181 ml; 2.486 mmole) at
-20C, and the mixture is stirred for 30 minutes at -20C and at
room temperature for 45 minutes. To this solution is added
methanol (10 ml), stirred for 30 minutes, diluted with water, and
stirred for 30 minutes at room temperature. The reaction mixture
is concentrated under reduced pressure, neutralized with 5% sodium
hydrogen carbonate solution in the presence of ice, and extracted
with ethyl acetate. The ethyl acetate layer is washed with water,
dried over sodium sulfate, and evaporated under reduced pressure to
give pale yellow foam. Purification of the foam by chromatography
over silica gel containing 10% water (50 g) using a mixture of
ethyl acetate and benzene (2:1) as eluting solvent gives the
product (17) as colorless foam (367 mg).
IR:~ 3 3420, 3350, 1787, 1720 cm
NMR:~ 3 1.75s2H, 2.02s3H, 4.33s2H, 4.48d(4Hz)lH, 5.00d(4Hz)lH,
6.97slH, 7.40mlOH.
Diphenylmethyl l-oxadethia-7-N-tertiary butoxycarbonyl-D-a-phenyl-
qlycinamido-3-methyl-3-cePhem-4-carboxylate ~18)
To a solution of diphenylmethyl l-oxadethia-7-amino-3-methyl-
3-cephem-4-carboxylate (17) (150 mg; 0.412 mmole) in a mixture of
tetrahydrofuran (8 ml) and acetone (4 ml) are added N-tertiary
butoxycarbonyl-D-a-phenylglycine (155 mg; 1.5 X 0.412 mmole) and
N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (152 mg; 1.5 X
0.412 mmole), and the mixture is stirred at room temperature for
14 hours. The reaction mixture is diluted with ethyl acetate,
washed with water, hydrochloric acid, sodium hydrogen carbonate
aqueous solution, and water, dried over sodium sulfate, and eva-
porated to give pale yellow foam. Purification of the foam by
18
1070688
chromatography over silica gel containing 10% water (30 g) using
a mixture of benzene and ethyl acetate (2:1) gives the product
(18) (248 mg).
; IR:y 3 3430, 1695, 1510, 1800, 1720 cm
S ~MR:~ 3 1.43s9H, 1.98s3H~ 4.18s2H, 5.00d(4Hz)lH, 5.27d(7Uz)lH,
5.65q(4;8Hz)lH, 5.67d(7Hz)lH, 6.77d(8Hz)lH, +7.4 aromatic H.
l-Oxadethia-7-D_a-phenylqlycinamido-3-methvl-3-cephem-4-carboxylic
acid trifluoroacetate (19)
To a solution of diphenylmethyl l-oxadethia-7-N-tertiary
butoxycarbonyl-D-a-phenylglycinamido-3-methyl-3-cephem-4-carboxy-
late (18) (246 mg) in methylene chloride (1.5 ml) are added anl-
sole (0.7 ml) and trifluoroacetic acid (1.5 ml), and the mixture
is stirred at 0C for 80 minutes and at room temperature for 40
minutes, and concentrated under reduced pressure. The residue is
treated with a mixture of ether and petroleum ether to give powder
of the product (19) as pale yellow powder (180 mg). m.p. decompo-
sition takes place from 135C.
IR:~ 3410, 1775, 1675, 1527 cm
NMR:~ 2 1.97s3H, 4.33s2H, 5.10d(3.8Hz)lH, 5.32slH, 7.53s5H.
W:~ 2 255 nm (~=7080).
DiPhenylmethyl l-oxadethia-7-D-mandelamido-3-methyl-3-cephem-4-
carboxylate (20)
. .
To a solution of diphenylmethyl l-oxadethia-7-amino-3-methyl-
3-cephem-4-carboxylate (17) (71.6 mg; 0.196 mmole) in ethyl ace-
tate (8 ml) is added successively a solution of sodium hydrogen-
sulfite in water (100 mg in 4 ml) and mandelic acid 0-carboxyan-
hydride (52.5 mg; 1.5 X 0.196 mmole) with vigorous stirring at 0 C.
After stirring for 1 hour at room temperature, the mixture is
diluted with ethyl acetate, washed with water, dried over sodium
sulfate, and concentrated under reduced pressure. The obtained
19
1070688
pale yellow powder is purified by chromatography over silica gel
containing 10% water (20 g) using a mixture of benzene and ethyl
acetate (1:1) to give the product (20) (80.4 mg).
IR:~ 3 3425, 1695, 1510, 1797, 1727 cm
NMR:~ 3 1.97s3H, 3.92brslH, 4.20s2H, 5.00d(4Hz)lH, 5.13slH,
5.63q(4;9Hz)lH, 6.98slH, to 7.4 aromatic H.
l-Oxadethia-7-D-mandelamido-3-methyl-3-cephem-4-carboxylic acid
(21)
To a solution of diphenylmethyl l-oxadethia-7-D-mandelamido-
3-methyl-3-cephem-4-carboxylate (20) (78.4 mg) in methylene
chloride (2 ml) are added anisole (0.3 ml) and trifluoroacetic
acid (0.3 ml) at 0C, and the mixture is stirred at 0C for 30
minutes, and is evaporated under reduced pressure. The residue is
dissolved in aqueous solution of sodium hydrogen carbonate, and
washed with ether. The aqueous layer is acidified with hydro-
chloric acid, and extracted with ethyl acetate. The extract solu-
tion is washed with water, dried over sodium sulfate, and evapora-
ted under reduced pressure to dryness. The residue is triturated
in a mixture of ether and petroleum ether to give pale yellow
20 powder of the product (21) (25 mg). m.p. about 120 C to about
135C.
Ymax 3400, 1781, 1712, 1673, 1524 cm
Compounds (17) and (19)
In a similar manner as are described above (8) to (16), the
title compounds are prepared with suitable protection in forms of
e.g. N-bertiary butoxycarbonyl and 0-formyl groups at the reactive
group in the acyl groups.
7-~D-2-(3-Methylsulfonyl-2-oxoimidazolidin-1-yl)carbonamido-2-
phenylacetamidol-3-methyl-1-oxadethia-3-cephem-4-carboxylic acid
(22)
:
. .
107(~688
To a solution of 7-(D-2-phenylglycinamido)-3-methyl-1-oxade-
this-3-cephem-4-carboxylic acid trifluoroacetate (19, 63.5 mg) ln
a mixture of tetrahydrofuran (0.8 ml) and water (0.2 ml) is added
triethylamine (40 ,ul). To the stirred mixture at 0C are added
3-methylsulfonyl-2-oxoimidazolidine (83 mg) and triethylamine
(40 ul). After stirring at room temperature for 15 minutes, the
mixture is acidified with 2N-hydrochloric acid, and mlxed with
water and ethyl acetate. The ethyl acetate layer is washed with
water, and extracted with aqueous sodium hydrogen carbonate. The
aqueous layer is acidified with 2N-hydrochloric acid, and extrac-
ted with ethyl acetate. The ethyl acetate layer is washed with
water, dried over sodium sulfate, and evaporated to remove ethyl
acetate. Trituration of the residue in ether gives the title com-
pound (22: 23 mg) as pale yellow powder. m.p. about 150 - 170 C.
IR:~ j 3325, 1787, 1730, 1678, 1527, 1168 cm
Diphenylmethyl 7-(2-thienYlacetamido)-3-methY1-1-oxadethia-3-
cePhem-4-carboxylate (23)
To a solution of diphenylmethyl 7-amino-3-methyl-1-oxadethia-
3-cephem-4-carboxylate (17: 85.5 mg; 0.235 mmole) in methylene
chloride (3 ml) at 0C are added 2-thienylacetyl chloride (56.5 mg,
0.353 mmole) and pyridine (19 ~ul; 0.353 mmole), and the mixture is
diluted with ethyl acetate, washed with water, dried over sodium
sulfate, and concentrated under reduced pressure to remove ethyl
acetate. Purification of the residue by chromatography over silica
gel containing 10% water (20 g) using a mixture of benzene and
ethyl acetate (2:1) as eluting solvent gives the title compound
(23 111.9 mg) as pale yellow foam. IR:~ ma 3 3420, 1792, 1722,
1680, 1505 cm 1.
NMR:~S 3 1.95s3H, 3.83s2H, 4.13s2H, 4.97d(4Hz)lH, 5.67dd
(4;9Hz)lH, 6.62d(9Hz)lH, 6.98slH, 6.9-7.3ml3H.
21
1070688
7-(2-Thienylacetamido)-3-methvl-1-oxadethia-3-cephem-4-carboxylic
acid (24)
To a solution of diphenylmethyl 7-(2-thienylacetamido)-3-
methyl-l-oxadethia-3-cephem-4-carboxylate (23; 110 mg) in methylene
chloride (3 ml) at 0C are added anisole (0.3 ml) and trifluoro-
acetic acid (0.3 ml), and the mixture is stirred at 0C for 30
minutes. The reaction mixture is evaporated under reduced press-
ure to dryness, and triturated in a mlxture of methylene chloride,
ether, and petroleum ether to give the title compound (24; 51.5 mg)
as pale yellow powder. m.p. 180-185C (with decomposition).
IR:~ i 3320, 1775, 1720, 1655, 1550 cm
Diphenylmethyl 7~ -diphenylmethoxycarbonyl-a-phenylacetamido)-
3-methvl-1-oxadethia-3-cephem-4-carboxylate (25)
To a solution of diphenylmethyl 7-amino-3-methyl-1-oxadethia-
lS 3-cephem-4-carboxylate (85.6 mg' 0.235 mmole) in a mixture of
tetrahydrofuran (6 ml) and acetone (3 ml) are added a-phenylmalonic
acid monobenzhydryl ester (245 mg, 0.705 mmole) and N-ethoxycar-
bonyl-2-ethoxy-1,2-dihydroquinoline (174 mg; 0.705 mmole), and the
mixture is stirred at room temperature for 4 hours. The reaction
mixture is diluted with ethyl acetate, washed with water, diluted
with hydrochloric acid, aqueous sodium hydrogen carbonate, and
water, dried over sodium sulfate, and concentrated to give heavy
syrup (241 mg). Purification of the syrup by chromatography over
silica gel containing 10% water (30 g) using a mixture of ethyl
acetate and benzene (1:4) for elution, and trituration in a mix-
ture of ether and petroleum ether gives the title compound (25) as
colorless foam (102.6 mg; 63~h)-
IR: ~ ma 3 3420, 3350, 1797, 1725, 1680, 1516 cm
NMR:tS 3 1.93s3H, 4.10s2H, 4.68s2H, 4.90d(4Hz)lH, 5.60q(4;10Hz)-
lH, 6.85s2H, ca. 7.25m.
22
' ' ~
1070688
7~~(a-Phenvlmalonamido)-3-methvl-l-oxadethia-3-cephem-4-carboxylic
acid (26)
To a solution of diphenylmethyl 7~-(a-diphenylmethoxycarbonyl-
a-phenylacetamido)-3-methyl-1-oxadethia-3-cephem-4-carboxylate
(25) (100 mg) in methylene chloride (3 ml) are added anisole (0.2
ml) and trifluoroacetic acid (0.2 ml) at 0 C, and the mixture is
stirred at 0C for 2 hours. The reaction mixture is concentrated
under reduced pressure to leave resldue, which is treated in a
mixture of ether and petroleum ether to give the title compound
(26) as almost colorless powder (46 mg; 89%). m.p. 115-120 C.
IR:~ j ca. 3400-2300, 1776, 1720, 1630, 1525 cm
Sodium 7~-~a-phenylmalonamido)-3-methyl-1-oxadethia-3-cephem-4-
carboxylate
The product of preceding example is dissolved in an aqueous
solution of sodium hydrogencarbonate (0.001 N) and diluted with
water to give a solution for antibacterial assay in vitro on
Mueller Hinton agar plates. The result shows strong antibacterial
activity against even gram negative bacteria including Pseudomonas
strains resistant to usually available penicillins and cephalo-
sporins.
'
.
. .~.j,,
23
