Note: Descriptions are shown in the official language in which they were submitted.
~S7;~t3
This invention i9 concerned with improvements in or
relacing to antibioti~s of the cephalosporin series.
The cephalosporin compounds in this speci~ication
~ are named with reference to "ceph~m" after J.~mer. Chem. -~
S Soc., 1962, 84, 3400, the term "cephem" referring to
the basic cepham structure with one double bond.
Many cephalosporin compounds possessing a
degree of antibacterial activity are known in the art, ~ ;
these compounds possessing ~ unsaturation and ordinarily
., . ~ ,.
being substituted at the 3-position by a methyl or
substituted methyl group and at the 7~-position by an
, :
acylamido group. It is now well recognised that the
antibiotic properties of a particular ceph-3-em-4 carboxylic
~-~
- ~ acid are predominantly controlled by the nature of both
the 7~-acylamido group thereof and the 3-position
substituent which the compound carries; considerable
s
research has been ùndertaken to find combinations of such
groups which will yield antibiotics with particular
properties.
Cephalosporin antibiotics are widely used in the
.~ treatment of diseases caused by pathogenic bacteria in human beings and animals, for example in the treatment
of diseases caused by bacteria which are resistant to
-- 2
~ .
^~ 5 ~ j .
Z~3 -
~ ~.
other antibiotics such as penicillin compounds and in the
treatment of penicillin sensitive patients~ In many
. .
. applications it is desirable to employ a cephalosporin
antibiotic whîch exhibits actlvity against both gram
positive and gram negative microorganisms, and a
~, .
significant amount of research has been directed to the
: development of improved broad spectrum cephalosporin
.
antibiotics.
The practical utility of a significant ~ :
-
number of known commercial and experimental cephalosporin~
antibiotlcs is limited by the;r relatively high
susceptibllity to the ~-lact:amases whlch are produced~ ~ ;
by many bacteria. A desirable property of a broad
spectrum cephalosporin~antibiotic is therefore that it
15 ~ should exhibit substantial resistance to fl-lactamases,
including those produced by gram negative microorganisms.
.i . ~
. ` ~
, ~ ~A further difficulty with many cephalosporin
; antibiotics intended for therapeutic applicatlons is that :
q they are subject to degradation _n vivo. Thus a
significant number of known cephalosporin antibiotics . ~;
have been found to suffer the disadvantage that following
administration they are deactivated, often rapidly,
3D~1 '
;~
:,~ . . ... . . . .
-
"J O~j7~d83
:
by enzymes (e~g, esterases) present in the body, ~ :
As a result of prolonged studies o numerous
cephalosporin compounds we have now found a cephalosporin
antibiotic having a particular combination of 7~-
acylamido group and 3-position substituent, namely
(6R,7R)-3-carbamoyloxymethyl-7-~2-(fur-2-yl)-2-methoxy-
iminoacetQmido]ceph-3-em-4-carboxylic acid (syn isomerj,
which compound has good broad spectrum activity
: coupled with the above-described desiderata of high
: 10 ~-lactamase stability and good stability in vivo
The present invention, therefore pro~ides
~ (6R,7R)-3-carbamoyloxymethyl-7-~2-(fur-2-yl)-2-
-~ methoxyiminoacetamido]ceph-3-em-4-carboxylicacid of
the formula
.. . ..
: :: H H
; ~ ~ CO NH - t
N 0 N ~ CH2O,cO~NH2
OCH3 COOH (I)
said compound being a sy~ isomer or existing as a
~.
mixture of ~y_ and anti isomers containing at least 90%
1 .'
' ~`
. ' .
~6~,
~l~5~tf~ ~3
;' ,
of the ~n isomer, and the non-toxic salts, biologically
acceptaible esters,l~oxides and solvates thereof, Most
preferably the compound is the syn isomer essentially
- free from the corresponding anti isomer,
The compound of the invention is defined as
` having the syn (cis) isomeric form as regards the
configuration of the group OCH3 with respect to the
carboxamido group, In this specification the ~y_
configuration is structurailly denoted thus:- `
:. , ': ;
~--C, CONH-
OCH3
The sy~ configuration is assigned on the basis of the
work of Ahmad and Spenser as reported in Can, J, Chem,
61, 39, ~340, : :
The term "non-toxic" as applied to the salts,
.,
esters, l-oxides and so~vates (especially hydrates)
of the compound of the invention means such derivatives
which are physiologically acceptable in the dosage at
which they are administered,
. ~ 5 --
, '', .
~;i, ~ j,; .
~;
~57;~E~3 ~
~ Salts which may be formed from the cornpound
: of general formula I include inorganic base salts
; such as alkali metal (e,g sodium and potassium),
::~ alkaline earth metal (e,g, calcium) and organic base
~:~ 5 (e g, procaine, phenylethylbenzylamine, dibenzylethylene-
. diamine, ethanolamine~ diethanolamine, triethanolamine
and N-methylglucosamine~ salts. The salts may also
.. ,~ ~ .
~ comprise resinates, formed with, for example, a polystyrene
... .
. ~ . i
~ resin or cross-linked polystyrene divinylbenzene copolymer
.~ ~ 10 resin containing amino or quaternary amino groups,
~:?
The compound of the invention,as indicated
abcve, possesses a particularly valuable combination of ;`~
. properties, exhibiting high antibacterial activity
against a broad range of gram-positive and gram-negative
.~ 15 organisms, The breadth of the activity spectrum is -
enhanced by the particularly high stability of the ;
: compo~nd ~ ~-lactamases produced by various gram-
negative organisms~ The compound shows the advantageous
property of good stability in vivo, particularly to
. 20 esterases, ~:~
; The properties possessed by the compound
:' ,,'' ' ' ':
~ 6 - ; ~
. ~ .
' si : ~
' 1, ~1
s
~ 3
accordi.ng to the invention render it useful in the
treatment of a variety of diseases caused by pathogenic
bacteria in human beings and animals
- A particular advantage of the compound of
formula (I) is that it is active against a wide range
of gram-positive and gram-negative microorganisms, e g.
Staphylococci including Staphylococcus aureus,
Streptococ us pyogenes and Streptococcus vilidans,
: ~ , Haemophilus influenzae,
Neisseria and Clostridia species, Escherichia
,
. coli, Klebsiella, ~roteus and Enterobacter species,
~ as evidenced by both in vitro and in vivo tests, The
compound exhibits good i vitro activity at inoculum
levels as high as 107 organisms/ml and possesses
particularly high in vitro activity against strains
of Haemo~hilus influenzae, Neisseria gonorrhoeae and
:. :
Neisseria meningitidis, The compound possesses very
high stability to ~-lactamases produced by a range of
; . :
gram-negative organisms as evidenced by, for
example, its in vitro activity against various ~- ~
- - 7 - :
. .'
'.
, ~,i,
~5~83
-lactamase-producing strains of Escherichia, Enterobacter
and Klebsiella species~ The compound is resistant to the
action of mammalia~ esterases and is thus stable in the
bodies o~ humans and animals as evidenced by ~igh levels
of recovery of unchanged compound in the urine.
Furthermore, the compound gives high serum levels following
,
parenteral administration to both human and animal
s
i subjects, while exhi~iting low sen~n binding.
Use of highly solub:Le base salts (e.g. alkali
metal salts such as the sodit~n salt) of the compound
, ,' . ~
is of advantage in therapeutic applications because
; of their rapid distribution in the body on administration
by injection.
.. . . .
We have found that sodium (6R,7R)-3-carbamoyloxy- ;
methyl-7-[2~~fur-2-yl)-2-methoxyiminoacetamido~ceph-3-em-
. ~.
4-carboxylate (~y~ isomer) occurs in a number of different
crystalline forms, including solvates, all of which are
embraced by the present invention. ~-~
The sodium salt is most conveniently prepared
by contacting a solution of the compound (II) in a polar
- organic solvent (e.g. dimethylacetamide), a mixture of suchsolvents (e.g. dimethylacetamide/acetone or dlmethyl~
,
, .
. ~ ~,.15",,"l,
....;
2~3
--formamide/industrial methylated spirits) or an aqueous
pol~ organic solvent system (e.g. aqueous aceto~e)
with a slight molar excess of sodium 2-ethylhexanoate
dissolved in a suitable organic solvent (e.g. an alkanol
~ 5 such as ethanol, a ketone such as acetone, or a chlorinated
;I hydrocar~on such as methylene chloride,an ester such as ethyl
~` acetate, an ether such as dioxan); conveniently at ambient
~! temperature, and then collecting the precipitated salt,
,. j
~1 if desired after cooling the solution (e.g. to 4C~. ~
~ 10 Where substantially anhydrous solvents are `;
`;, employed ln this process, Form I sodium (6R,7R)-3-carbamoyl- ;
' oxymethyl-7-[2-(fur-2-yl)-2-methoxyiminoacetamido]ceph-3-
",! em-4-carboxylate (syn isomer) is obtained, this material
i
;~'containing about 1.5% water. Where the solvent system
;~-,,15 contains more than about 2% of water, however, Form II
salt is obtained, this normally containing about 2~/o water,
Where the solvent system contains more than about 60%
dioxan, Form III salt is normally obtained, this material -
comprising a dioxan solvate containing about 1 mole
of dioxan, although Form II salt may be obtained if
a water wet solvent system is used at elevated temperature
(e.g7 60-80C)~ Crystallisation of amorphous freeze-dried
:, :
, ; :
'''-'' '' ' ' ; ,, ' ',~. :
~ Z ~3
,
sodium (6R,7R)-3-carb~moyloxymethyl~7-[2-(fur-2-yl)-2-
methoxyiminoacetamido~ceph-3-em-4-carboxylate (syn isomer)
from appropriate dry, water-containing or dioxan-rich
solvent systems similarly yields Fonm I, Form II or
c Form III salt respectively.
Exposure of Form I salt to water vapour (e.g.
!, at 75% relative humidity) causes the salt to absorb
;~ further water and undergo a change of cr~stalline fonm
;l leading generally to Form IV salt. The resulting
material contains about 4% water (i.e. about 1 mole)
;~/ and is believed to be a hydrate. This change is
~ reversiblP, so that Form IV salt may be converted to
- ~ .
~ Form I salt by, for example~ drying in vacuo over a
.. . .
desiccating agent such as phosphorus pentoxide. Fonm
l~ ~ 15 II salt does not absor~ further water when exposed to
i water vapour, but may be converted to Form I salt ;
by heating (e.g. for about 5 minutes) a suspension
of Form II material in nearly boiling methanol.
Fonm III salt obtained by reactio~ of the
compound and sodium 2-ethylhexanoate in ~ioxan-rich
solvent systems as described above is normally precipitated
tO .,
- ,;~ ~ .
.' . '. .. ,*
~, ,1:, ~ . .
...
,: , ~. , , - ,
~iO S7~3
~,
as a gel, which may be dried in vacuo to give a solid
having very low bulk derlsity and exhibiting little or
no crystallinity. Crystalline Form III salt may,
however, be obtained by treating an aqueous solution
S of the sodium salt with a substantial excess (e.g. about
8 volumes) of dioxan, if desired together with a minor
proportion of ethanol, collecting the resulting white,
needle-shaped crystals, conveniently after cooling to a
reduced temperature (e.g. 4C), washing the product wit~
dioxan and then drying the crystals (e.g. in vacuo at 20C).
Form III salt i5 hygroscopic and on exposure
to water vapour (e~g. at 75% relative humidity) loses alI
the dioxan present and fonms Form IV material, which may
~i ~ then be dried (e.g. over phosphorus pentoxide) to give ~ -
' -:
; : 15 FOD I salt. I crystalline Form III material is
treated in this way, the crystal habit of the product
appears to be retained throughout the sequence of
.
transformations. Form III salt may also be converted
to Form I salt by heating a suspension of Form III
material in nearly boiling methanol; this trans~ormation
does result in loss of crystallinity where crystalline
'
5~ 33
` ~:
,. :,
Form III material is used. :~.
The four forms of sodium (6R,7R)-3-carbamoyloxy-
methyl~7~[2-~fur-2-yl)-2-methoxyiminoacetamido~ceph 3-
em-4-carboxyla~e (~y~ isomer) des'cribed above are
characterised by the ~ollowing X-ray powder patterns ~ :
(d-spacings and intensities) and IR spectroscopic data~
Jj
., . ~,, .
owder patterns s .
~: ~ Camera - Debye-Scherrer, radius 114.6 mm
.1 :
~ Radiation - Copper Kd ~ 1.5418 A '~
,
Intenslties (I) by visual comparison with
cali4rated standard
'! : :
: .
'i ~ , ~ '
~:, ' * ' :
.
., . ' ' '
.',
.
' ,j,~, , ~
' ;' ' ' ', ' . ''' ' ': '. ' . ':
73Z~3
,
;
Form I
'
d I d I
8.33 80 3.05. 4
7.44 4 2.93 14 (broad)
6.S5 45 2.72 8 )poorly
)re-
6 . 38 5 2 . 69 10 ) solved ~ ;
5.86 4 2.57 9
5.36 4 2.b.7 6
4.8~ 100 2.40 lO :
4.56 35 2.35 lO
~.36 6 ~.26 4
4.19 40 2.20 3
3 . 95 ~6 2 .11 8 (broad)
3.82 24 2.04 3
3.6~ ~8 1.94
3 . 4 7 2 8 1 . 8 g 5
3.32 lO 1.82 6 (broad)
3,1g 10 1.77 2
l3
~' ~? , '
~ .
~ , . , .. .. ,, . ; - ~ . . . .
7Z~33
.'', ~
, .
Form II
; ~.
d I d
~ . 8,78 60 3.49 14 ;:
-~. 7.81 9 307 6 (broad)
6~65 25 2.91 8
. ., ~ .
4 . 68 100 (broad) 2 . 77 6
4 45 10 2.32 3 . (br~ad)
.1 '~-: ~.
` ~ ~ 4~20 10 2.19 2 ~ ~.
3.76 20 (broad)2.08 2 ~-
,~; Form III ~:
:,1
`' ~ d I cl
1 4 . 9 8 6 0 4 . 2 9 2 0
:.' 12.95 ~0 4~16 100 ::
10.16 - 20 3.81 25 ~broad)
8.23. 45 3.60 20
. ~, 7 . 52 5 ~. 3 . 47 5
6 . 61 65 3 . 32 10
6 .08 3 3 . 26 30
~!
5.57 20 3.13 17 (broad~
4.98 40 2.43 10
4 . 73 60 2 . 15 15 ::~
.
', I ~ ~'
., _~ . :
.'', ,~ : ,
, . ~ .
.,, .,. :,... . .
~5~gZ~
,
Form IV
- d I d
8.85 70 3-75 35
; 7 .80 6 3 ,10 ' 1
7 . 15 25 2 . 93 4
6.01 20 2.76 12
5 . 06 18 2 . 62
4065 100 2.41 2
~` 4.30 25 2.30 3
:
4. 01 25
.
,., -
:.; :
. .
.1 , . , :
., .
`1 ~
.-...................................... . .
. .
:~ :
~ . :
;~,
.j
,,
~i ~
';, t ~ ~
'
.
' ' ' . ' . ' - ' '' , ` .
7~33
IR Spectra
Spectrometer - Perkin-Elmer 521, range 4000 - 650 cm
Spectra recorded Eor Nujol (trademark) mulls (b~nds
, .
associated with Nujol are excluded~
~ Form I
.` 5 3520 w* 1590 s 1262 m 1004 m ~:
3460 m 1556 m 1248 m 978 m
3370 m 1534 s 1170 m 918 w
3265 s 1480 m 1152 m 882 s
1770 sh 1410 s 1134 w 878 sh
, 10 1752 s 1400 s 1112 m 838 w
-~ 1706 s 1338 s 1076 m 814 w :
.~ 1660 s 1328 s 1054 sh 790 w :.
., .
1620 s 1284 m *1042 s 778 w
754 m
.
,
.
-16-
.,
.
' ~
,'~ ' . '-.
,.
'
.... . . . .
~", , , ,: , ~, , :
~15~ 3
Form II
3526 m 1544 s 1152 m 920 w
3492 w 1478 m 1142 m 882 m
';3364 m 1412 s 1112 m 878 w
3250 m 1398 s 1080 m 840 w
1758 s 1332 s 1058 m 818 w
169$ s 1284 m `~';1045 m 792 w
1665 s 1268 m 1005. m 752 m
1642 sh 1240 m 980 m
1624 s 1172 m 954 w
Form III
3465 m 1532 s1155 m 820 w
3415 m 1482 m*1124 s 800 w ,-
` ,
3345 m 1412 s1078 m 790 w
- 3275 m 1395 s~';1058 s 768 m
. 3200 m 1326 s1048 s 748 m
1780 s 1285 m1014 m
!
, 1702 s 1~60 m985 m
1660 s 12~0 m938 w
1632 m 1225 m888 m
!
. ~
f 1618 s 1196 w878 s
. 1552 m 1180 m836 w -;
"
, ` ~ ~ .
"
"~
. r ~ \ ' ~ '
: ~ :
~7~3
.; .
~ Form IV
~,' - ' .
:', 3585 w 1594 s 1264 m 1008 m 788 w
~;
: 3520 w1555 m 1240 m 980 m 752 m
` 3370 m1540 m 1172 w 956 w
~:3260 s1478 m 1152 m 920 w
1758 s1410 s 1114 w 882 m
,
R 1712 s1400 s 1078 m 878 w
~ . 1664 s1330 s 1058 m 838 w
'i
:~ 1620 s 1285 m 1042 m : 818 w
s = strong
,.1 ~
, ~ ~ sh = shoulder
Y~ ~ m= medium
~ . ~
w = weak
. : ~
* deno~es bands characteristic of each crystallîné-~orm. ~ :
~, . .
: :.
3, :
'' . '
' ~'~ :.
:
~, .
~' ~
.
~,
: ,. . .
., ~ ~ ......
572133
Where insoluble sal~s of the compound (I) are
desired in a particular application, fior example for
use ;n depot preparations,, such salts may be ormed in
conventional manner, for example with appropriate
organic amines,
The invention further provides a process for
the preparation of the antibiotic compound of formula I
(as hereinbefore defined) or a non-toxic salt, biologically
: acceptable ester, l-oxide or solvate thereo~f which
1 : :
comprises either (A) condensing a compound of general
formula H H ~ :
B
~ ~ N~ ~ CH20,CO,NHR 2
`' 7i COOR~
(whereln B is ~S or ~S-~O; Rll is hydrogen or a
: ,c~rbo~y~ ~locking group, e,g, the residue of an ester~
,1 .
: : : forming~aliphatic or ,araliphatic alcohol or an ester- :
,~ 15 forming phenol, silanol or stannanol, or a symmetrical
., :
or mixed anhydride group derived from an appropriate acid;~
and R is hydrogen or an N-protecting group, e,g, an
. acyl group, especially a lower alkanoyl group such as ~ - :
~ -
acetyl, a halo-substituted lower alkanoyl group such
'; ` ' `.
" ` .
` - 1 9 - . ~
., .
~ :':
"; ' ' `
5~;~83
as mono-, di- or tri-chloroacetyl, or a chlorosulphonyl
group) or an acid addition salt thereof,(e,g an acidaddition :.
salt formed with, for example, a mineral acid such
. as hydrochloric, hydrobromic, sulphuric, nitric or
5 phosphoric acid or an organic acid such as methane --
,. -: .: -
~ sulphonic or toluene p-sulphonic acid),or an N;silyl
: derivative thereof, with an acylating agent
corresponding to the acid
C C00H (III)
~:. . OCH3
~ ~ or (B) reacting a compound~of the formula :
I : : H H
C.CO.NH~
: N 0 N ~ CH2OH
OCH3 . COORll (IV)-
.
(wherein B and R have the above-defined meanings)
with a carbamoylating agent serving to~form a carbamoyloxy- :
methyl group or an N-protected carbamoyloxymethyl group at
the 3-position; whereafter, ;f necessary and/or desired in
- 20 -
!~ ~
~ i7;~3
each instance, any of the foll~wing reactions ~C), in
any appropriate sequence are carried out:-
~,
(i) removal of any carboxyl blocking or N-protecting
groups, and (ii) reduction of a cephalosporin sulphoxide
S product to yield the corresponding sulphide; and finally ~-
; (D) recovering the desired compound of formula I if
desired after conversion of the compound to a non-toxic
salt, biologically acceptable ester, l-oxide or solvate
thereof : ~-
;- 10 Non-toxic derivatives of the compound of formula I
,
may be formed in any convenient way, for example according
to methods well known in the art, Thus, for example,base .
salts may be formed by reaction of the cephalosporin
~ .
acid with sodium or potassi.um 2-ethylhexanoate, Biologically
~ .
acceptable ester derivatives may be formed using conventional
- esterifying agents, l~Oxides may be formed by treatment
-~ of the corresponding cephalosporin sulphide with an
appropriate oxidising agent, for example with a peracid
" ~ .
such as metaperiod.ic acid, peracetic acidS monoperphthalic
acid or m-chloroperbenzoic acid, or with t-butyl ~ -
; hypochlorite conveniently in the presence of a weak - base such as pyridine
The compounds of formula (I) may conveniently be
prepared bycondensinga compound of formula (II) with
. an acylating
; - 21 -
~' ' .~', .
,
~ L~57
`:
agent comprlsing an acid halide, particularly an acid
; chloride or bromide, corresponding to the acid (III),
Such acylation may be effected at temperatures of from
-50 to +50C, preferably -20 to +30C~ The acylation
5 may be effected in aqueous or non-aqueous media.
Acylation with an âcid halide may be efected in
the presence of an acid binding agent (e.g. a tertiary
amine such as triethylamine or dimethylaniline, an
inorganic base such as calcium carbonate or sodium bi-
10 carbonate, or an oxirane7 preferably a lower-1,2-
s alkylene oxide such as ethylene oxide or propylene oxide)
which serves to bind hydrogen halide liberated in the
acylation reaction,
.
~ The free acid form of the compound of formula (III)
;
~15 may itself be used as the acylating agent. Such
acylations are desirably conducted in the presence
,
,
of, for example, a carbodiimide, such as N,Nt-diethyl-,
~dipropyl-or dlisopropylcarbodiimide, N,N'-dlcyclohexyl-
carbodiimide, or N-ethyl-N'-y-dimethylaminopropylcar-
bod~imide; a carbonyl compound such as carbonyldiimidazole;
i -22-
,, .
" .
-
71'Z8~
or an isoxazolinium salt such as N-ethyl-5-phenylisoxa-
zolinium-3'-sulphonate or N~t-butyl-5-methylisoxazolinium
. .
perchlorate, The condensation reaction is desirably ;~
effected in an anhydrous reaction medium, e,g, methylene
. ~ ;
chloride, dimethylformamide or acetonitrile,
Acylation may also be effected with other amide
forming derivatives of the free acid (III) such as,
: for example, a symmetrical anhydride or a mixed anhydride,
e,g, with pivalic acid or formed with a haloformate
such as a lower alkyl haloformate, The mixed or
symmetrical anhydrides may be generated in situ, Thus, :~
for example, a mixed anhydride may be generated using
. .. .
~ ~ N-ethoxycarbonyl-2-ethoxy-1,2~dihydroquinoline,
; Mixed anhydrides may also b~.formed with phosphorus ;:
' ~ lS acids (for example phosphoric or phosphorous acids),
sulphuric acid or alïphatic or aromatic sulphonic
acids (for example ~-toluenesulphonic acid~
~ ; Where a starting material of formula (IV) is
s employed, suitable carbamoylating agents include :
:. :
isocyanates of general formula
~13 NCO (V) ~ :
,
. . - 23 - : ~
~ ::
, . . .
1057'h8~
where R13 is a labile substituent group; such carbamoylating
agents serve to form at the 3-position an N-protected
carbamoylox~methyl group of formuIa
'' ` --CH20.CO.NHR13
(where R13 has the above~defined meaning) which may be
converted to the desired unsubstituted 3-carbamoyioxymethyl
~; group by subsequent cleavage of the group R 3 9 for example
by hydrolysis,Labile groups R 3 which are readily cleavable
upon such subsequent treatment include chlorosulphonyl and
bromosulphonyl; aralkyl groups such as benzyl, p-methoxybenzyl
and diphenylmethyl; t-butyl; halogenated lower alkanoyl
groups such as dichloroacetyl And trichloroacetyl; and halo-
- genated lower alkoxycarbonyl groups such as 2,2,2- ,-
trichloroethoxycarbonyl. R groups of this type, with the
- 15 exception of aralkyl groups such as diphenylmethyl, may
; generally be cleaved by acid or base catalysed hydrolysis
.
(e.g, by base catalysed hydrolysis using sodium bicarbonate).
Halogenated groups such as chlorosulphonyl, trichloroacetyl
and 2,2,2-~richloroethoxycarbonyl may also be cleaved re~
ductively, while groups such as chloroacetyl may also be
cleaved by treatment with thioamides such as thiourea. Aralkyl
~ . .
, ,
~ ~5~ 3
groups such as diphenylmethyl are conveniently cleaved by
treatment with acid, e~g. a strong organic acid such as
trifluoroacetic acid.
The carbamoylating agent of formula Y is desirably
;~ 5 used in excess (for example at least 1.1 moles relative
to the compound of formula IV). The carbamoylation may be
assisted by the presence of base, e g, a tertiary organic
base such as a tri-(lower alkyl) amine (e~g. triethylamine~
or by employing the acid V in the form of an alkali
Si lO metal (e,g. sodium) salt, although such assistance may not
. .
be necessary in the case of more active isocynates, e.g.
compounds CV) when R13 is a strongly electron-withdrawing
group such as chlorosulphonyl or trichloroacetyl.
i, , ,
s Carbamoylations involving reaction of a free acid IV
13
15 with excess isocyanate (V) wherein R is a group such
- as chlorosulphonyl or trichloroacetyl are th~s of particular
practical advantage by virtue of the simplicity of the
reaction conditions, since there is no need for temporary
- blocking and subsequent deblocking of the 4-posltion
` 20 carboxy group of the cephalosporin and since the electron
withdrawing R13 group in the resulting N-protected 3-
, . ~, . ,
j -25-
,, ;~ .
~. . . .
" , .
``` -
5~
-carbamoyloxymethyl cephalosporin product is readily
removed by, for example, hydrolysis with aqueous sodium
bicarbonate.
~; Itishould be noted that it may be convenient to
S retain or even to introduce an N-substituting group R13
during transformations of intermediate 3-carbamoyloxymethyl
compounds in order to minimise unwanted side reactions
involving the carbamoyloxymethyl group.
Another useful carbamoylating agent is cyanic acid,
which is conveniently generated in situ from, for example,
an alkali metal cyanate such as sodium cyanate, the
reaction being facilitated by the presence of an acid,
~ e,g. a strong organic acid such as trifluoroacetic acid.
- Cyanic acid effectively corresponds to the compound of
formula V wherein R is hydrogen and therefore
., ~
~7 converts compounds of formula V directly to their 3- ;
;~ carbamoyloxymethyl analogues.
3~Hydroxymeth~l starting material for use in the
process of this embodiment of the invention may be prepared
`~ 20 by, for example, the methods described in British Patent No.
~ 1,121,308 and Belgian Patent No~ 783,449.
., ' ~
., , `'
~ -26-
' ~
:
5~7Z~33
Any blocking group substituting the 4~carboxy
group of compounds of formula II or IV is desirably a
group which may readily be split off at a later stage of a
reaction sequence and advantageously is a group containing
~` 5 1-20 carbon atoms~ Suitable blocked carboxyl groups are well ~?
~- known in the art, a list of representative groups bei~g included
in our aforementioned Belgian Patent NoO 783,449. Preferred
blocked carboxyl groups include aryl lower alkoxycarbonyl
groups such as p-methoxybenzyloxycarbonyl, ~-nitrobenzyloxy ~:~
~ 10 carbonyl and diphenylmethoxycarbonyl; lower alkoxycarbonyl
:~. groups such as t-butoxycarbonyl; and lower haloalkoxycarbonyl
:. groups such as 2,2,2-trichloroethoxycarbonyl. The carboxyl
~. : blocking group may subsequently be removed by any of the
... , , :
appropriate methods disclosed in the literature; thus, for
.example, acid or base catalysed h.ydrolysis is applicable
. in many cases, as are enzymically-catalysed hydrolyses~
Where at the end of a given preparative sèquence
.. . . . .
a sulphoxide analogue of the compound of formula I is obtained,:
conversion to the corresponding sulphide may, for example~ ~ :
.~i 20 be effected by reductlon of the corresponding acyloxysulphonium
. or alkyloxysulphonium salt prepared in situ by, for example, :
,, : :: .
` -27-
.
.
.
'
- . , , . , . . , ;
,, . . , . . , , , . , ,
~"
~2
reaction with acetyl chloride in the oase of an
acetoxysulphonium salt, reduction being effected by~ for
; example, sodium dithionite or by iodide ion (as in a
solution of potassium iodide in a water miscible solvent
5 such as acetic acid, tetrahydrofuran, dioxan, dimethyl-
~: formamide or dîmethylacetamide), The reaction may be
effected at a temperature of -200 to +500C
The anti~io~ic compound according to the
l;~ invention may be formulated for administration in any
s 10 convenient way, by analogy with other antibiotics,
;. for example, in the form of pharmaceutical compositions
comprising the compound of formNla I or a non-toxic
derivative (e g, a salt, biologically acceptable esterj7
l-oxide or solvate) thereof adapted for use in human or
,~ è
~ 15 veterinary medicine, Such compositions may be presented
,:~, .
s for use in conventional manner with the aid of any
necessary pharmaceutical carriers or excipients :: ;
.
.. ,~, ~ .
,
.
- 28 -
. ,
, .' '
~s,
:~ .
~ . , , ., - , . . .
,,,;, ,: , , ,, . . , : , ,; ~ ,
5~
The antibiotic compound according to the invention
may be formulated for injection and may be presented in
unit dose form in ampoules, or in multidose containers
`` with added preservative. The compositions may take such
forms as suspensions, solutions and emulsions in oily or
aqueous vehicles, and may contain formulatory agents such
as suspending, stabilising and/or dispersing agents.
Alternatively the active ingredient may be in powder form
fsr reconstitution with a suitable vehicle, e.g. sterile,
; 10 pyrogen-free water, before use.
For veterinary medicine the compositions may, for
example, be formulated as intramammary preparations in
either long acting or quiok~release bases.
In general the compositions may contain from 0.1% ~
15 upwards, e.g. 0~1-99%, pref~rably from 10-60% of the ;
active material, depending on the method of administration.
Where the compositions comprise dosiage units, each unit ~ ~
will preferably contain 50-1500 mg of the active ingredient. ~ -
.,; . .
~ The dosage as employed for adult human treatment will
,~
;~'~' ' i
ij .
" .
~ - 29
., ':
.. . . ~ , . . - .
.
::~ 105~2B3
.
preferably range from 500 - 4000 mg per day, depending
on the route and frequency of administration,
The compound according to the invention may be
.
administered in combination with other compatible
`- 5therapeutic agents such as antibiotics, for example
.: .
- penicillins, other cephalosporins or tetracyclines, '
.
. .,i , .
". ~ . .
~, . . .
.
. .......................................................................... .
.:
'~' : ' '. :
: ~'
,~
'' ~ . ',:
" . .
'~ ~
, :~
.
., .
. '. . .
~.~ . . . .. .
; ~572~3
~".
The following examples illustrate the invention.
` All temperatures are in C. Melting points were
~` determined on a Kofler block.
.
~ , . - ., .
: . :
.~, , .
.,: :
.. , :
.
...
.~`.
.. ~ .
.,, . . ::
. :.; .
. .
~',; .
!' ~ ' i
~"
~,J ' ~ ' ' . :
"~. ' ' . '
. ~ .
,'.'~ ' ' ' '
.'~. ,
,'~ . '
. , :
`' ~ 31 ~:
.. ` :
.
.
. -
~7~
A~ PREPARArlON or 5TARTING M ERIALS
Preparation 1
a).iDi~henylmethyl (6R,7R)-7-(Thien-2-ylacetamido)-3~
Trichloroacetyl isocyanate (13.2 g~ 70 mmole) was
added to a stirred suspension of diphenylmethyl (6R,7R)-
3-hydroxymethyl-7-(thien-2-ylacetamido~ceph-3-ern-4
. .
carboxylate (26.0 g, 50 mmole) in anhydr.~us`acetone (600 ml) : :
.~ at 20. The solid soon dissolved and after the mixture ~`
~`" 10 had~been stirred at 20 for 1 hour it was chilled for 1 ;:
, .
hour and the resulting solid was filtered off and washed -.
with ether to giv the title ~ (33.1 g, 93%), : -
.~ . m.p. 183 to 184; C~D1 ~ 24 (c 0.95 in DMS0); ~EtfH
235 nm (~ 14,500) and AEtOfH 256 nm ~ 8,820).
IR~ NMR and microanal~tical data confirmed the
structure as that of the title compound. - -
;; b~ DiphenylmethYl (6R,
-.,. . . . :
:.
. .
Anhydrous pyridine (31ml, 0.384 mole) was added
. to a solution of phosphorus pentachloride (20 g, 96 mmole)
i.n dry d;chloromethane (300 ml)
,:
'' ' '3~
, ~, .:
~ .. .
, . ~. . . ~ , . . . .. .
16~S~7Z~33
at 3. The suspension was stirred for 10 minutes at 3
:,
- and diphenylmethyl (6~,7R~-7 (thien-2-ylacetamido)-3- ~
:, .: , .
trichloroacetylcarbamoyloxymethylceph-3-em-4-carboxylate
(22.5 g, 32 mmole) was added; the reaction was stirred
at ca. 2 for 1 hour. The dark solution was poured
slowly into a cold (0) anhydrous mixture of methanol
(80 ml) and dichloromethane (200 ml) with the
temperature kept below 5. The temperature of
' the solution was then allowed to rise to 23 and, a~ter
`~ 10 stirring the solution at this temperature for 1 hour, .
~ : , . :.
~ water (200 ml) was added. The organic layer was separated
-~ and washed with 2N-sulphuric acid, water, sodium bicarbonate
~ solution and water, dried over magnesium sulphate, and
, :.i ~ ~
.`.6,'; ~ ~ evaporated in vacuo. The resulting oil was dissolved in
ethyl acetate and a so~lution of toluene-~-sulphonic~acid
monohydr~ate (6.0 g, 31.~ mmole) in ethyl acetate was added.
; The combined isolutions (ca. 350 ml) were poured into diethyl -~
;: , ,
`~ ~ ether (ca. 1 litre) ~and the resulting solid was filtered
~, off and dried in vacuo to give the title compound
(17~2 g, 72~/o) ~ m.p; 150 to 153; [a]21 ~ 7.5 (c 0~82 in
.
s DMS0); ~max 263 nm ( E 7,600) and ~înf 267 nm ( E 7 ~ 3 50) ~
... .
- - ~ 33
,i
,. ..
...
j, :
,................. ~ ,
. .
33
..
IR, NMR and microanalytical data confirmed the structure
as that of the title compound.
Evaporation of the iltrate and trituration of
the residue with ethanol a~forded unchanged starting
.,
material (3.2 g~ 14.2~
- c) Di~henylmeth~l (6~R)-7-Amino-3 ca bamoyloxymethyl-
The toluene-~-sulphonic acid salt of diphenylmethyl
- (6R,7R)~7-amino-3-Lrichloroacetylcarbamoyloxymethylceph-3-
;il 10 em-4-carboxylate (17.2g, 22.7 mmole)was dissolved in a
mixture o~ anhydrous methanol (900 ml) and acet~l chloride
(45 ml) and let to stand at 20 for 5 hours. Removal
;
~ of the solvent under reduced pressure gave an oil, ~-hich
-~ ~ - was dissolved in dichloromethane. This solution was
. 15 shaken with aqueous sodium bicarbonate solution and then
.. . . .
washed with water. Toluene-p-sulphonic acid monohydrate
.. .. .
(~.3 g, 22.7 mmole) was added and the solvent was evaporated ~?
in vacuo. The residue was dissolved in hot isopropanol
(ca. 150 ml) and the solution was poured into diisopropyl
ether (ca. 600 ml). The precipitated solid was filtered
i,
: .' ' ' -3~ '
- ,3q - "
. :
,~., .
" .
. . .
. ., - . j, ~ ,
:
~, - " , ,, ~ , ' ' " , ~ , '
~ 5~ ~ 3
:
' ; ,:
o~f and dried in vacuo to give the title compound
", O
~: (8.9 g, 64%~, m.p. 110 to 112; [~]DL -14~ (c, 1.0 in
` CHC13) 3 ~max 259 nm ( E 6,120~ and ~inf 227 nm ( 15,800).
-. ' IR, NMR and microanalytical data confirmed the
structure as that of the title compound~
E~!____on 2
.
`. Diphenylmethyl (6R,7R)-7-Amino-3-carbamoyloxymethylceph-3- :
,;
,.~ .
. em-4-carboxylate Toluene-p-su ~onic Acid Salt
.i A stirred suspension of phosphorus pentachloride (156 g~,
`~ 10 0.75 mole) in dry dichloromethane (l.S litres) was cooled
` in an ice-bath and treated with pyridine (60.5 ml, 0~75 mole)
. at such a rate that the tempPrature of the mixture remained at
- ca 20 to 25. The mixture was stlrred and cooled to 8 ~nd .
.~ . . .
~ ~ diphenylmethyl (6R,7R)-7-(thien-2wyl)acetamido-3-trlchloroacetyl-
~' - ' . .
I5 carbamoyloxymethylceph-3-em-4-carboxylate (354.5 g,0.5 mole)
was added in portions over 10 minutes. The mixture was~ stirred
at ca. 8 for 1.75 hours and then added over 10 minutes to a
,. .
stirred mixture o~ butane-1,3-diol (225 ml, 2.5 mole) and
dichloromethane (500 ml) precooled to -20 so that the tem-
.. . .
perature o~ th~ mixture was kept in the range -15 to -20.
` _ ~ _
:
, ~ . . . .
~72~33
The cooling b~th was removed and the mixture was stirred at ca.
-10 for 20 minutes. Water (1 li.tre) was added and the two-
phase mixture was stirred for 30 minutes. The aqueous phase
- was extracted with dichloromethane (2~500 ml), and th~ organic
.: :
5 phases were washed sequentially with 2N hydrochloric acid (1 litreJ
com~ined and evaporated to a brown gum~ The gum wa~ dissolved
in methanol (3,6 litres~ and this solution was stirred and
treated with saturated aqueous sodium hydrogen carbonate solution
(1.2 litre~ over a period of 10 minutes. The mixture was
- 10 stirred at ca. 20 for 1.5 hourc; and a small quantity o~ bro~nsolid was removed by filtration. The yellow filtrate was
concentrated in vacuo (bath temp. not greater than 40) to ca.
1.5 litres and water (1.5 litres~ was added. The resulting
, . .
suspension was refrigerate~ for 1 hour~ and the yellow salid
15 was filtered off, washed well with water, sucked as dry as
possible and dried in vacuo at 40 for 24 hours. The greasy solid
thus obtained, followed by toluene-p-sulphonic acid monohydrate
(81 g, 0.425 mole), were added to stirred chlorofonm (2 litres).
.
After several minutes the toluene-p-sulphonic acid salt
20 began to crystallise. Stirring was continued for a further
J 30 minutes, after which the water was removed azeotropically
., ' ~,~ .
' ~' ' ~ ,.
'
; ~
~ 5~Z~3
,
n vacuo with continuous replacement o the chloroform so as
to maintain a volume of 2 litres. The suspension was re-
.
frigerated overnight and the product was filtered off, slurry
washed with chloroform (2x250 ml), ~efiltered9 washed by
,
displacement with chloroorm ~250 ml) and dried in vacuo at
40 to give the title compound as an off-white crystalline
solid (237.8 gg 74,1%); ~maX(EtOH) 262 nm ( 7,250); the
..
NMR spectrum (Me2SO-d6) indi.cated-the presence of 0.25
.
mole of chloroform.
0 Preparation 3
- ~(6R~7R)-7-Amino 3-carbamoy~ox~methylceph-3-e _ 4-carboxy~ic A ~d
Diphen~lmethyl (6R,7R)-7-amino-3-car~amoyloxymethylceph-3-
` em-~-carboxylate toluenP-p sulphonic acid salt (300.0 g, ~-
- 0.44 mole), solvated with~ca. 0.6 mole of chloroform; was
.. .
added in portions over 30 minutes to a stirred mixture ~
. . .
~ trifluoroacetic acid (300 ml) and anisole ~300 ml) immersed
.f in a water-bath at 20. The temperature of the mixture
. .
rose from 23 to 28 over the first 20 minutes but fell back
to 26 by the end of the addition. The golden yellow solution
was stirred for 1 hour, the temperature falling to 21, and
,., : :
57
" .
.. . . . . . . .
. . ~ . : .
~S~t~83
: '
`
,.~,,
was then added to a stirred mixture of ethyl acetate
(105 litres) and water (1.5 litres~ immersed in an ice-
bath. The pH of the stirred mixture was adjusted to 3,8
over 10 minutes with ammonia solution (S.-G. 0,880), the
temperature rising to 38. The suspension was stirred
.
and cooled to 10~ over-1.~5 hours and filtered. The cream
solid was washed with water (750 ml) and ethyl acetate
(4 x 200 ml) and dried in vacuo to give the title compound
(llS~6 g, 96-2 %); ~max (pH6 pho~phate~ 265 nm (E7~7~0);
. ~
purity by HPLG (high pressure liquid chromatography) 99~7 %.
MicroanaIytical data confirmed the structure as that
- of the title compound.
; .
:: .
::,. ..
.;
: "~! ,
: :' :
.,"; ~ :
.~ .
',, ' . ' :,
."':~ - '
.
~' ''~ , '
-', `
'~', : ' '
'' r "''
. :'~ . .
,
- 38
.:
.
` ' ~' ~ '
j~
. ~ .
a~
~; A stirred solution of (6R,7R~-7-(R-5-amino~5~
carboxypentanamido)-3-hydroxymethylceph~3 em~4-carboxylic
acid mono potassium salt (ca~ 67% pure) (62,00g, ca. 100
mmole) in water (300 ml) was cooled to ~5 and treated
with a solution of benzoyl chloride (17.4ml, l50mmole) in
acetone (200ml) over 25 minutes. The pH of the reaction
mixture was maintained at 8.2 to 8,5 by the controlled
addition of 30% w/v aqueous tripotassium orthosphospate.
The mixture was stirred for a further ten minutes and was
then covered with ethyl acetate (140ml) and the pH was
~ i
lowered to 5.6 with orthophosphoric acid. The layers were
separated and the aqueous portion washed with more ethyl
acetate (2x400ml). The aqueous portion was diluted with
water (2 litres), covered with ethyl acetate (2 litres)~
and the pH of the stirred mixture taken to 2~0 with
orthophosphoric acidO The layers were separated and the
.
- 20 aqueous layer extracted with further ethyl acetate (3x
1500ml), The combined extracts were washed with saturated
brine (800ml~, dried, and concentrated in vacuo
..
- 39
' , , ': ' ' '
Z133
': . . :.
to a volume of 300 to 400ml. The resulting slurry was
stirred with ether (2 litres~ for 20 minutes and was
then filtered. The collected solid was washed with ether
' (2x250ml) and dried in vacuo (1 'mm.) to give the title
~ as a white solid (54.95g, 88.6% W/W) 9 []20 + 74 ?
(c 1-00~ dioxan); Amax (pH 6 buffer) 231nm (El/m 275),
266nm (inflexion9 ElCm 145). The NMR spectrum (Me2SO-d
showed the presence of ca. 20% lactone impurity and ethyl
~;~ acetate (ca~ Q.4mole~. -
: ~ .
~ io b) (6R ~ 7-(R-5-Benzoylamino-5-carboxy~__tanamido)-
','~ . ' :
.~
cid Monosodium Salt.
The product of (a) above (25.46g) was treated
~; . .
with a solution o~ chloroacetylisocyanate (9.0Qg9 75mmole~
in dry acetone (92ml). The resulting solution was stirred
for ~5 minutes at ca. 20, then cooled to ca. 5 over 5
:., :
minutes and treated with a solution of sodium 2-ethyl~
'~ hexanoate (8.47g~ 51mmole) in acetone ~51ml). The
; crystalline suspension was stirred at ca. 5 for 5
x 20 minutes, and the solid was collected by filtration, washed -
ith acetone (80ml) and ether (250ml), then dried in vacuo
(lmm.) to give the title ~ ound (27.23g, 107 .0/0 w/w), .,
.,
; ~ V~, G~,,x ;,
., .
~ 72
.: .
[a~D -~72.0 (c 1.00, 3% aqueous NaHC03)) A aX(pH6 ~uffer)
227nrn (El/m 249) 7 261nm (inflexion, ElCm 105)~ The NMR
- - spectrum (Me2SO-d6) showed the presence of ca.35% lac~one
impurity and chloroacetamide (ca. l.Omole).
S c~ (6R,7R)-7-Amino-3-chloroacetylcarbamoylox~nethylceph~
3-em-4-carboxylic Acid
A suspension of the product o~ (b) above (24.77g)
,. .
` in dry methylene chloride (320ml) under nitrogen was
cooled to ca. 10 with stirring. Pyridine (17.60ml,
.,
218.0mmole), then dichlorodirnethylsilane (16.80ml,1~9.2mmole)
.
~ were added and the pale-bro~l suspension was stirred at ~
.
. ca. 20 for 20 minutes and was then cooled to -17.
.. ~, . .
Phosphorous pentachloride (10.84g, 52.0mmole) was added
and the mixture was stirred at -17 to ~23 for 2 hours.
15 ~ Pyridine (6.48ml9 80.4mmole) was addedJ and the mixture
was added to methanol (104ml ~ 20ml washings, pre-cooled
to-35~) at such a rate that the temperature of the stirred
solution did not exceed -10 . The stirred solution was
allowed to reach ~2 over 25 minutes, then ~ater (88ml)
was added, and the pH of the mixture was taken from 0.6
to ~.. 8 with aqueous ammonia solution (S.G. 0.880). The
: resultlng two-phase mixture containing a precipitated
.'~ ~ ~ ~ '.
, ' :
l ",~ :
,.~,,... ,, , . , ~ .; ~. ,
`
- ~5~9~8~
: i solid was refrigerated for 1 hour and was then filtered~
. , .
The solid was successively washed with 50% v/v aqueous
methanol (lOOml), methanol (80ml), and methylene chloride
(40ml), then dried in vacuo (lmm.) to give the title
. 5 ~ as a cream powder ~6.86g, 27.7% wjw), ~a]D
48 (c 1.04~ Me2SO); Amax(pH 6 buf~er) 237.5nm (ElCml49),
1/
. . .
.~-,, .
.:,
.
~ ,
`". ' . :
: .
,.,; ~
. - , . . . :
. ;~ ~ . .
~ ~,
: : .
t
f~
:',j ' ~ ~ "
~' ' ' . " .
. . - , ,.'
,~" , ' ' ~"'~''',.
, ,1 . .
~ '
~,'`' ' .
S' ~ ''~.
,1 '."'
... . .
., .
: ~S~83
~ .
B) EXAMPLES
~xam~le 1
a) Diphenylmethyl (6R,7R)-3-Carbamoyloxymethyl-7-[2-~ur-
,, ~
.. . .
~. 5 isomer)
-
Method (i)
Crude diphenylmethyl (6R,7R)-7-amino-3~carbamoyloxy- :~:
i ~ methylceph-3-em-4 carboxylate toluene-~-sulphonic acid
... salt obtained from the corresponding 3-trichloroacetyl-
carbamoyloxymethyl compound (25.0 g, 0.33 mole) was
..
dissolved in a mixture of ethyl acetate and aqueous
sodium bicarbonate solution. The organic layer was : ;,
separated, washed with water7 dried over magnesium sulphate, -~
; ~and evaporated on a rotary evaporator to give diphenylmethyl
(6R,7R)-7-amino-3-carbamoyloxymethylceph-3-em-4~carboxylate
(11.5 g, 0.262 mole, 77%) as a foam.
2-(Fur-2 yl)-2-methoxyiminoacetic acid (~y~ isomer)
(5.32 g, 0.312 mole~ in dry dichloromethane (100 ml) was
added to a solution of this amine in dichloromethane :~
(50 ml) cooled to 3; followed 10 minutes later by a
solution o~ DL-dicyclohexylcarbodiimide (6.5 g~ 0.312 mole) :
_, . . .
~ ~S ' , '.
:', '
'-'
.. .
.: . . .. : .. .
.. " , - . ~,. . . .. ..
~ ~057ZB3
;'~ ' ' '
~` . .. ..
in dichloromethane (30 ml). The reaction mixture was
stirred in an ice-bath for 45 minutes during which time a
solid (presumably N,N'-dicyclohexyl urea) crystallised out.
- This was filtered off and discarded, and the filtrate was
washed with aqueous sodium bicarbonate solution and water,
dried over mangesium sulphate, and evaporated to dryness.
~` ~ The residue was triturated with ethanol to give a crude
product (lC.6 g ~ which was purified by chromatography on
,.,j
3 Silica Gel (lkg). Elution with 10~/o acetone in
dichloromethane remo~ed non-polar impurities, and
frac~ions eluted with 20% acetone in dichloromethane gave
:. .
the title com~Ro~md (4.8 g, 31%), m.p. 199 to 202; -~
[alD1 + 14 (c, 1.0 in DMS~ maH 277 nm (~18,600) ~ ;~
and Ai f 270 nm (~17,900). --
T' 15 IR,N~R and microanaly~ical data confirmed the
`~ structure as that of the title compound.
~ Method (ii)
... .
Triethylamine (1.86 g, 18.4 mmole) was added to a
dichloromethane solution (35 ml) of 2-(fur-2-yl)-2-methoxy-
:i . .
~i 20 -iminoacetic acid (~ isomer) (3.1 g, 18.4 mmole). After
cooling this solution in an ice-bath for 5 minutes, oxalyl
chloride (1.57 ml. 18.~ ~mole) and a drop of N,N-dimethyl-
formamide were added. After 0.5 hours the solven-t was
., 1~ ~t
. " .. .. . . , . , , , , , ~ , , ,
.... . .. .. . . . .
f~
removed under reduced pressure and the solid residue was
dried for 1 hour ~n vacuo. Anhydrous ether (150 ml) was
added to dissolve the acld chloride that had been formed
and the insoluble triethylamine hydrochloride (2.5 g)
~ 5 was filtered off. The'ether was evaporated on a rotary ,,
;~ evaporator and the oily residue was redissolved in "
- . .
dichlororn~thane.
'' Diphenylmethyl (6R,7R)-7-amino-3-carbamoyloxymethyl-
ceph-3-em-4-carboxylate toluene-p-sulphonic acid salt
s 10 (8.9 g, 14.7 mmole) was dissolved in anhydrous dichloromethane.
This solution was shaken with àqueous sodium bicarbonate
solution, washed with water, and dried over magnesium
sulphate. To this solution,of the free amine were
-added the dichloromethane,solution'of 2-(fur-2^yl)-2-
,~ 15 methoxyiminoacetyl chloride (~y~ isomer) and propylene
.
~! oxide,(S ml). After 10 minutes a crystalline solid- ~
, (l.l g) was filtered off, which was subsequently
identified as diphenylmethyl (6R,7R)-7-amino 3-carbamoyloxy-
.
~, . , Lr ~ ' '''" '' ' '
,. , . ',~ '
~ ~ .
", .
'"';3i;"~
,r~~ .
~S~Z83 :::
.
.,,
; .
~` methylceph-3-em-4-carboxylate hydrochloric acid salt.
The iltrate was washed with 2N-sulphuric acid, water,
-~i aqueous sodium bicarbonate solution and water7 and was
~ dried over magnesium sulphate and evaporated to dryness
. ~ .
~; 5 to yield the title co~pound (2.5 g, 30.5%), similar in ~
: ,i
physical properties to the product of Method (i) above.
Z~ b) ~ Sodium ~ R~7R)-3-Carbamoy oxymethyl-7-[2-(fur_2-yl)-2-~
~ ~ methoxyiminoacetamidolce~h 3_em-4-carb
.
i Trifluoroacetic acid (20 ml) was added slowly to
. " ~ ~ ~
- ~ ~ 10a mixture of anisole (5 ml) and diphenylmethyl (6R,7R)-3- ; ;
ca ~ amoyloxymethyl-7-r2-(fur-2-yl)-2-met~ioxyiminoacetamido~
' ceph-3-em-4-carboxylate (syn isomer) (~-7 g, 8~mmolej which ;~
had been cooled in an ice-bath. The flask was shaken ;
... . - :
occasionally during the next 10 minutes to ensure complete ~ ~ ~ Y
solution of the-solid. It was then removed from the ice-
bath and excess tri~luoroacetic acid was removed on a rotary
evaporator. Trituration of the residue with ethyl acetate
,. : .
~ (5 ml) gave (6R,7R)-3-carbamoyloxymethyl-7-[2~(fur-2-yl)-2~~
.,~, .
. . .
"
J
. .
2 ~ 3
methoxyiminoacetamidolceph-3-em-4-~rDoxylic acid (~y~
isomer) (3.3 g, 94%) as a solid which was filtered off
and washed with diethyl ether.
The free acid was dissolved in ac~tone and a
slight excess of sodium 2-ethylhexanoate ~n acetone (8.0 ml
of a molar solution) was added. After the reaction mixture
had been stirred at 0 for 2 hours, the title salt (2.3 g,
. - .
~' 73V/o) was filtered off. This was combined with another batch
... .
of the title salt (0.8 g) and purified by ~ashing an aqueous
' 10 solution (250 ml) with ether (2xlO0 ml, lx50 ml) r The
'! ' aqueous solution was ~reeze-dried to give odium (6R!7R)-3-
~;
carbamoylo ~ ~2-(f~ y~ metho~iminoacetamidol-
ceph-3-em-4-carboxylate ~ isomer? (2.66 g),
; ~a~D +73 5 (c 1.06 in MezSO);Am x 274 nm (- 16,500);
lS v (Nujol) 3450, 3330, 3250, (NH,NH2 and H20), 1752
(azetidin-2-one) and 1652 and 1600 cm (carboxylate);
.s
Me~SO-d6)0.24 (d,J8Hz, CONH), 2.12 (d, J2Hz, furyl C5-H),
3.25 and 3.30 (m,.furyl C3-H and C4-H), 3.44 (broad s~
CONH2), 4.34 (dd, J 5 and 8Hz, C7-H), 4.92 (d, ~
C6-H), 5.15 (q, J13Hz C3-CH2), 6.07 (s, NoCH33 and 6.58
-- _ .
, ~7
.- ~
,: ~ ~. .. . .
57~83
' ,
(q. J 18Hz, C~- H2)
(Found: C, 42.0; H~3.8; N, 12.1; S~7.2
C16H15N~NaO8SØ5H20(455.37) requires C, 42.2; H, 3.S;
N, 12.3 and S, 7.0 %)O
.
r (syn isomer)
A stirred mixture of N,N-dimethylacetamide (75 ml),
`~ 10 acetonitrile(75 ml), triethylam-ine (42 ml, 0.3 mole~
"t ~ ' : , ',.
3 and (6R~7R)-7-amino-3-carbamoyloxymethylceph-3~em-4- -
;~ ~ carboxylic acid (16.40 g~ 0~06 mole) was immersed in an
ice-bath and water (10 ml) was added The mixture was
.,
sti~red at O to 2 for 45 minutes, the solid slowly ;-
15 d~ssolving to glve a yellow solution. ~ ~
., .
Meanwhile a stirred suspension of phosphorus
,:. , ,
pentachloride (14.99 g, 0.072 mole) in dry dichloromethane
~150 ml) was cooled to 0, and N,N-dimethylacetamide
(27.5 ml) was added. The resulting solution was recooled
to -10 nnd 2-(fur~2-yl)~2-methoxyiminoacetic acid (~y~
isomer) (12.17 g, 0~072 mole) was added. The mixture was
,j . . .
stirred at -10 for lS minutes and crushed iGe (35 g)
_ 48 -
'
,
. . :, ~, . . .
- . . - .,
.
:
. was added~ The mixture was stirred at 0 for 10 minutes,
. .,
whereafter the lower dichloromethane phase was added over
10 minutes to the cephalosporin solution prepared above,
cooled to -~0 so that the reaction temperature rose steadily
S to 0. The mixture was stirred at 0 to 2 for 1 hour, where-
after the cooling bath was removed and the reaction temp~rature
:. ,,' .
.j allowed to rise to 20b over I hour. The reaction mixture ~ ~'
.~ was then aclded slowly to 2N hydrochloric acid (100 ml) diluted ~:
.; with cold water (1.15 litres) at 5. The pH o the two~
.~ :
; 10 phase mixture was adjusted to below 2 with 2N hydrochloric
acid (10 ml), and the mixture was stirred and ~cooled to 5.
The solid which precipitated was filtered, washed with :~
dichloromethane (100 ml) and water (250 ml), and dried in
vacuo a~ 40 overnight to give th title compound (22.04 g, -~
~, ~15 8606%), ra]2 ~ 58 (c 1.08, Me2S0); AmaX (pH 6 phosphate
., bufEer) 274 nm ~ 17,500); vmax (Nujol~ 34809 3440, 33671 3255
and 3133 (bonded NH and NH2), 2725 and 2590 (C02H), 1760
- (azetidin-2-one), 1728, 1712 and 1698 (OCONH2 and ~2H), 1655
and 1530 cm (CONH),~p(Me2S0-d6) 0.25 (d, J 8 Hz; CoNHj, 2.18
' 20 (s, furyl C5-H), 3.28 and 3.4 (m, fur~l C4-H and C3-H), 3.42
;-~ (8~ CONH2), 4.19 (dd9 J 8 and 5 ~z; C7-H)~4.80 (d, J S Hz
, , .
' ~ ~ ?
', , :
~ , . . . ~ .
5~72~3
;~ .
~` C6-H)9 5.06 and 5,39 (q, J 13 Hz; C3-CH2), 6.09 (s; NOSH3),
6.44 (collapsed ABq; C2-H2), and 7.99 (0.03 mole
CH3CON(CH3)2).
.~: ~ ' ' :
~ 5 a) ( ~ -3-
., S ~e `~' ''`
,
A stirred solution of (6R;7R)-7-(R-5-amino-5~
~`i carboxypentanamido)-3-hydroxymethylceph 3-em-4-carboxylic
: : 10 acid~ monopotassium salt (18,45 g, 30 mmole) in water
.
~` ~93 ml) was cooled to 0 to 5 ~ice/water bath) and treated
with a solution of benæoyl chloride (5.19 ml, 45 mmole)
. : in acetone (63 ml) over 25 minutes~ The pH of the reaction
mixture was maintained at pH 8.S (i 0.1~ by the controlled
:15 addition of 30% w/v aqueous tri-potassium orthophosphate
(ca, 100 ml~. Thè mixture was stirred for a further 5 .
... ~ , .
minutes, overed with ethyl aceta~e (150 ml) and the pH was
then lowered to 5.6 with orthophosphoric acid. The layers
were separated and the aqueous portion washed with additional
- ethyl acetate (2x300ml), The combined washingswere extracted
with water (200 ml), The combined aqueous portion and washings
were diluted with water (600 ml), covered with ethyl acetate ~
(600 ml), and the pH of the stirred mixture was taken to 2.0 with
_
,. . : . ., , ,. ~
i~ ~
83
orthophosphoric acid~ The organic layer was separated
and quinoline (10.64ml, 45 mmoles) in ethyl acetate
(25 ml) was added, with stirring, to give a white precipi-
tate. The aqueous portion was extracted with further ~ -
ethyl acetate (3 x 300 ml) and these were added to the
suspension containlng quinoline. The mixture was stirred
for 1 hour at ca 18 and then concentrated in vacu~ to
ca~ 500 ml. Ether (900 mlj was added with stirring and
~ .
after 30 minutes the solid was collected by ~iltration, -; -
washed with ether (5x200 ml) and dried in vacuo (1 mm) to
:,, ! .
~ive the title ~e~ a~ a white powder (19.20g, 104.1%
w/w), Ca]D + 780 (c 1.00, dioxan); ~max (pH 6 buffer)
258 nm (inflection, ElC%m 185). IR and NMR data confirmed
the structure as that of the title compound containing ca.
15% lactone impurity and trace amounts of ekh~r and ~hyl
acetate. ;-
b) ( ~
,
Ac~ t ~
,
:
; ~o The product of (a) above (4.24 g, equivalent~to 7
mmole) was treated with dry dioxan (100 ml) in which it
partially dissolvedl To the stirred mixture was added
krichloroacetyl-
- 51 -
;~
" .
ZB;~
isocyana~e (2.90 ml, 2~.5 mmoles). The resulting
solution was stirred for 30 minutes, and was then
clarified by filtration and evaporated in vacuo to give a
yellow oam. This was dissolved.in acetone (ca. 10 ml)
and poured into stirred isopropyl ether (ca~ 100 ml). ~`
The resulting white precipitate was cbllected by filtration
and dried in vacuo (1 mmj to give the ti:tl ~
~ :
as a white powder (6.26 g, 147.8% w~w). NMR data
~; conlrmed the structure as that of the title compound and
also showed the presence of lactone (ca. 22%),
isopropyl ether (0.75 mole), dioxan (0.2 mole) and a
small amount of acetone. `
c) (6R/7R)-7-Amino-3-trichloroacetYlcar~amoyl~ymethyl-
ceph-3-em- o rl~xvlic AC d
; 15 ~ A~solution of the product of (b) above (4.77 g, equi-
valent to 6 mmoles)~in dry methylene chloride (40 ml)
under nitrogen was cooled to ca. 10 with stirring.
Pyridlne (2.20 ml, 27.3 mmoles) then dichlorodimethylsilane ~ ;
(2.10 ml, 1~7.4 mmoles)~were added and the brown solution
- 20 ~ was stirred at ca. 17 for 20 minutes and then cooled
to -17. Phosphorus pentachloride (1.355 g, 6.5 mmoles)
, S~~ ' '~:
,
, , '~:
.
'!~'A
:,
7z ~ 3
was added and the mixture was stirred at ca. -16 for
~ 2 hours. Pyridine (0 81 ml, 10 mmoles) was added ~nd
- the mixture was added to methanol (13 ml ~ 2.5 ml
washings, pre-cooled to -35) at such a rate that the ~;
temperature of the stirr~d solution did not exceied -10.
The stirred solu-tion was allowed to reach ~9 over 25
minutes, water (11 ml) was then added and the pH of
the mixture was taken from 0.3 to 3.8 with ammonia solution
(S.~G. 0.880). `The resulting two-phase mixture
containing a precipitated solid was refrigerated for
.
l hour and then filtered. The solid was successivel~
washed with 50% v/v aqueous methanol (12 ml),
methanol (10 ml) and methylene chloride, (5 ml) then
dried in vacuo (1 mm) to give the ~ as
a cream powder (1.22g, 25.6% w/w), ~a]D +44 (c 1.02,
Me2S0); ~ (pH 6 buffer) 240 nm (E1/m 133), 263 nm
(El%m 140). NMR data confirmed the structure as that ;~
~- of the title compound.
.
d) (6R,7R)-3-Carba ~ methyl-7-~2-(fur-2-yl)-2--
.
methoxyiminoacetamido~ce ~ 4-carboxylic Acid :;
(syn is mer) ~ -~
~ ~ 3
' ~ :.'
' `"
~;' .
,., . : . . .. .. .
"
;
~L~S7;~83
.~` .
Phosphorus pentachloride (4.5 g, 21.5 m~loles) was
dissolved in dry methylene chloride (90 ml) and cooled with
stirring to -15. N,N-Dimethylacetamide (9 ml) was added
,
.. ~ . . .
slowly, keeping the temperature below -10, and the mixture
was stirred for lO minutes. 2-(Fur-2-yl)-2-methoxyimino-
acetic acid (syn isomer) (3.66 g, 21.5 mmoles) was added
. and the mixture stirred at -lS for 15 minutes. Crushed
ice (18 g) was added carefully so that the temæerature
of the mixture did not exceed -7. The mixture was
stirred for 10 minutes and lhe organic portion was
separated and added dropwise to a solution of (6R,7R)-7-
. .
amino-3-trichloroacetylcarbamoyloxymethylceph-3-em-4
carboxylic acid (7.52 g, 18 mmoles) in dry methylene
chloride (90 ml) and triethylamîne (5.5 ml, 40 mmol~s),~
. .
- 15 precooled to -10. The acid chloride solution was ~
.
added over 20 minutes, the temperature of the reaction ~ ~;
mixture being maintained between -10 and -8. The -
:, .
mixture was then stirred for~80 minutes, during which
time the temperature was allowed to rise to +3, and
~ 20 methanol (6 ml) was added. After a further 5 minutes
; stirring, the solution was extracted with 3% wjv aqueous
;,,,i,l ~'~
. .
5"7~B3
,
`'~` .
~ sodium hydrogen carbonate (2x120 ml) and water (150 ml). ~-
.
; The combined extracts were 1eft to stand at ca. 20 for
: 3.5 hours, and were then washed with ethyl acetate
~100 ml) and acidified to pH 1.5 with concentrated
~ , .
hydrochloric acid. The resulting deposited oil was
extracted into ethyl acetate (2x300 ml). The combined
organic portions were wa5hed with water (2 x 100 ml), dried
(MgS04) and evaporated n vacuo to give a yellow solid
(7.1 ~) which was stirred with ether (150 ml), filtered,
and dried in vacuo (1 mm) to ~ive the ~ as
a pale yellow solid (5. 20 g, 68.2% of theory), A
(pH 6 buffer) 275 nm (El cm 385). IR and NMR data ~ ~:
confirmed the structure as that of the title compound - ~:
containing a trace of ether. . ~;
: - .
:
: ..
~~ ~.
'
~`
. i.. ~, . : .
.~ ,, `I, j, .
.: . . . , . : . :.,.:. . .~.
:: . . , . .. .. ~
. .
2~
..
.: ..
N,N-Dimethylacetamide (105 ml) was added to a
solutlon of phosphorus pentachloride (750mg, 3.6mmole)
in anhydrous dichloromethane (15 ml) cooled to -10. A~ter -
10 minutes, 2-(ur-2-yl)-2-methoxyiminoacetic acid (~y~ ;
isomer) (612mg, 3.6mmole) was added to the resulting
suspension, which soon became a clear solution and was ;-
stirred at ~10 for lS minutes. Ice (3g) was added and
1:: ~ : .
~: .
' ~: ':'''"'
~ - 56
7283
.
after 10 minutes the layers were allowed to separate in a
dropping funnel The organic phase was slowly (over 5 min-
utes) run into a cooled (-10 ) solution of ~6R,7R)-7-amino-
3-chloroacetylcarbamoyloxymethylceph-3-em-4-carboxylic acid
(l.OSg, 3mmole) in dichloromethane (15ml) containing
triethylamine (0.9ml, 6.5mmole). Methanol (lml) was added : ;
after 40 minutes, and 5 minutes later the reaction mixture ~ -
. . ,
was extracted twice with 3% w/v aqueous sodium bicarbonate
~-l - solution (150ml). The aqueous extract was washed with ethyl
~ 10 acetate t25ml) and left at 2.0 for 4 hours. The solution ~
~ was washed twice with ethyl acetate, acidified with 2N- :
~ hydrochloric acid, and extracted 3 times with eth~l acetate.
,
The combined organic layers were dried over magnesium
~ sulphate, decolourised with activated charcoal, and
; 15 ~ evaporated in vacuo to give a pale-yellow solid ~l.l5g,~
87%). This was washed with diethyl ether and iltered off~
.. , . ' ~:
. , _ ~ , .
S ~ :
- ' ' . ' ' ~,:
- ',',,;
''' ~'
` ::
''' '
,,~'
. . , . . , . , . , . :.. ~..... :
~ 5~2~33 ~:
tolgive the ~ (0.91g,71%); ~pH6 274nm
max
(~17,300) The IR and NMR spectra of the product agreed
with those of an authentic sample.
` 5 (
-` isomer)
:~ .
~ Method (i)
~.. ~ . , -:
Acetone (750 ml) was cooled to 0 and treated with
,i :
trichloroacetyl isocyanate (2808 ml, 240 mmole), and the
solution was recooled to 0. (6R,7R)-7-~2-(fur-2-yl)-2-
methoxyiminoacetamido]-3-hydroxymethylceph-3-em-4-carboxyli~
a~id (sy~ ~somer~ (45,6 g, 120 mmole) was added to the
stirred isocyanate solution in portions ov r 5 minutes so
thàt the reaction temperatùre did not exceed 6. The
yellow solution was stirred for a further 15 minutes and
` methanol (4.5 ml) was added. The solution was con~entrated
to 60ml and the concen~rate dissoived in methanol (750ml). ~;-
Sodium bicaxbonate (45~3 g, 540mmole) in water (600 ml)
.
was added9 followed by activatèd charcoal (4~Sgj, and the
resulting sus~ension was stirred at room temperature for
2 hours. The charcoal was removed by filtration through
~.
- 58 - -
: . , .. , ~: .
. . .
~ `
~ 2 ~ 3
'........... ; ,~
Keiselguhr and the light yellow filtrate was adjusted to
pH 4.5 by the addition of dilute hydrochloric acid. The ;~
solution was concentrated to half volume under reduced
; pressure and an equal volume of water was added. The pH
was adjusted to 2.0 wîth dilute hydrochloric acid and the
product was isolated by filtration, washed with water ;~
(3 x 150 ml) and dried at 40 for 16 hours ln vacuo to
give the title co~ound (37.46 g~ 73 5%); [a~D ~63.7
~c 1.0; 0.2 M pH 7 phosphate buffer); ~max (pH6 phosphate
buffer) 274 nm (~ 17,600).
IR, N~R and microanalytical data confirmed the
structure as that of the title compound.
. :
,: ~) ~ .
~ ~ A slurry of (6R,7R?-7-[2-(fur-2-yl)-2- ~
.
meehoxyiminoacetamidoJ-3-hydroxymethylceph-3-em-4-carboxylic
acid (syn isomer) (3.81 g, 9.55 mmole) in dichloromethAne~
(70ml)/tetrahydrofuran ~25ml) at S was treated with -
.~. ,,
dichloroacetyl isocyanate ~2.6 ml, 25 mmole). The reaction ~
,
mixture was then treate`d in the same manner as in Method
(i) to give the title comDound (3.36g, 83.0%); ra]D
63; A ax 273.5nm (~ 17,800); with similar IR and N~R
spectra to the product of Method (i). ~
. S~
, : .
( ,. ,~,. . .
~7~ ~ 3
~ethod (iii)
A slurry of (5Rj7R)-7-~2-(fur-2-yl)~2-
methoxyiminoacecamido]-3-hydroxymethylceph-3-em-4
carboxylic acid (~ isomer) (19.05 g, 50mmole) in dry .
acetonitrile (250ml) was treated at between 5 and 10 -:
: with chlorosulphonyl isocyanate (6.33 ml, 75mmole) in
acetonitrile (80ml)O :
. : The reaction was stirred at between 0 and 5 for 10 ~:~
minutes and water (50ml) was added. The mixture was ~ :
.: :
~ 10 stirred at ca 20, and after 20 minutes a white crystalline, . -
solid separated. Evaporation and filtration gave the
(18.17g, 85.`7%); ~a]D ~ 62.5; ~m~x
273.5nm ( 17~820); with similar IR and NMR spectra to
: the product of Method (i). A second crop (1.88g, 8.6%)
: 15 of the product, with similar constants, was obtained by ; ::
,
~ evaporation of the mother liquors.~
,~ .
Lsomer : ;
(6R?7R)-3~Carbamoyloxymethyl-7-~2-(fur-2-yl)-2
- 60 -
.. . , : ~ , . .,: .. . ..... . .. .. . .
~i72~3
methoxyiminoacetamido]ceph 3-em-4-carboxylic acid (syn
isomer) (lOOg) in N9N-dimethylacetamide (400ml)/acetone
(1 litre) was treated with sodium 2-ethylhexanoate (40g)
in acetbne t200ml). The mixture was seeded and stirred at
ambient temperature for 1.25 hours. The product was
, filtered off, washed with acetone (500ml) and then ~
slurried with acetone (3x300ml) and finally slurried with ,
~ ether to give the title com~ound (101.4g, 92.5%)
`' ~ containing (a~ter equilibration in the atmosphere) 0.65mole ,
'equivalents of water. The product has [a]~61 (c 0.5,
pH 4.5 phosphate buffer) and ~max 273 nm ElCm 412 (H20).
~ IR and N~IR data confirmed the structue as that of
; the title compound, the IR spectrum indicating that the - ,~
compound was the Form I salt.
lS Method (ii)
. The process of Method (i) was repeated9 except
that the cephalosporin acid was initially dissolved in
N,N-dimethylformamide/industrial methylated spirits in
place of N,N-dime,thylacetamide/acetone, to yield the ~,,
title compound (80V/~) similar in properties to the product ~
of Method (i). The IR spectrum indicated that the compound ~ '
as the Form I salt.
.,, a;l ,. ~ - ,
........ .
~357;~i~3
~ Method (iii)
. .
f (6R,7R)-3-Carbamoyloxymethyl-7-L2-(fur-2-yl)-2-
~ methoxyiminoacetamido~ceph-3-em-4-carboxylic acid (syn
- ' isomer~ (4.24g, 10 mmoles) was dissolved in N9N-dimethyl~
acetamide (20ml) which had been dried over molecular
,:~
sieve (Linde 4A) for 24 hours. To this was added a '~
solution of sodium 2-ethylhexanoate (2.0g, 12 mmoles~
,~.
recrystallis~d from dioxan and dried over phosphorus
pentoxide) in ethyl acetate (80ml) which had been dried
over molecular sieve (Linde 4A) for 24 hours. The ~ ~;
solution was stirred in a c]osed vessel for about lS
minutes untll crystallisation commenced and then cooled
to 4 for one hour. The product was ~iltered~ washed
'. : ~ : : . ..
with dry ethyl acetate.(~ lOOml) and, while s~till wet
15- with this solvent, was transferred to an oven and dried ;
at 20~in vecuo over phosphoru~ pentoxide overnight to
afford the title compound (3.89 g, 87%).
.
,J , - The IR and NMR spectra of the product conformed
to those of an authentic sample.
. ` ~.~.
,~,j .
:
7283
~.
.~ , ..
isomer ' :~
Method (i) ::
Charcoal (0.2g) was added to a solution of (6R,7R) ~
~3-carbamoyloxymethyl-7-C2-(fur-2-yl)-2 methoxyiminoat~et- :
amido]ceph-3-em-4-carboxylic acid (~y~ isomer) (4.00g,
9042 mmole) in a mixture of acetone (132ml) and water
(1.33 ml)~ The suspension was stirred for 30 minutes and
filtered through a bed of Kieselguhr, the filter bed ~:;
being washed w~th acetone (lOml). A filtered solution of
sodium 2~ethylhexanoate (1.66g, lOmmole) in acetone :~
(20ml) was added over 1 hour to the stirred filtrate.
The resul~ing suspension was stirred for a further 10
minutes, an~ the white solid was filtered off, washed
with acetone (2 x 25ml) and dried in vacuo to give the
(4~06g~ 93.0%); Ca~D + 60~ (c O.91,H20);
~maX(H2o) 274 nm ( 171400); ~F~und: C~41.0~ 41.2; H, ~;
3.45, 3.6; N~ 12.3, 12.4; Na, 5.2; S, 6.6, 6.85; H20, 2~7
2.7.. C16H15N~NaO8S. ~7 H20 (459.0) requires C, 41.89
H~ 3.6; N, 12.2~ Na~ 5.0; S, 7~09 H20, 2.7%); purity
by HPLC 99.4%. The NMR spectrum of the
- 63 -
:
~l~5~3
product resembled that of an authentic sample, and the
IR spectrum indicated that the product was the Form IX ~ ~
,, saltO `' '
: M
(6R,7R~-3 Carbamoyloxymethyl-7-C2-~ur-2-yl)-2-
methoxyiminoacetamido]ceph-3-em-4-carboxylic acid (~y~
isomer) (16.98 g, 40 mmoles) was a~ to a stirred mixture
of acetone (333ml) and water (8.5 ml). After treatmen~ with
.: charcoal and filtration of this solution, sodium 2-ethyl~
. .
hexanoate (7~32 g, 44 mmoles) in acetone (85 ml3 was
:: added slowly over 1 hour. The reaction mixture was stirred ~ :
for 15 minutest filtered, and the product was washed with
a~etone (2 x 65 ml) and dried in vacuo at 20 overnight
- ~ .
to yield the title om~ (17,95 g, 98.5%), containing
~ O,5 mole H20. The NMR spectrum of the product conformed
: to that of an authentic sample, and the IR spectrum
.
indicated that the product was the Form II salt. :~
Example 8
'.
~
' . :
Sodium (6R,7R)-3-carbamoyloxymethyl-7- L2- (fur-2
. .
6~ -
~5~
.
yl)-2 methoxyiminoacetamido]ceph-3~em-4~carboxylate (~y~
isomer) (4 0g) was dissolved in water (20 ml)~ Industrial
methylated spirits (20 ml) and dloxan (160 ml) were
added and the solution was filtered and then set aside at
4 to crystallise. The very white needle~shaped crystals :
wPre filtered off, washed with dioxan (lOOml) and~ while ~:
still wet with dioxan, wer~ transferred to an oven and
dried a~ 20 ~n vacuo overnight to yield the title compound
(3 96 g, 78.5%). The IR and NMR spectra of the product
conformed to those of an authentic sample~ ;
Example 9
~ bamoyloxymethyl-7-C2-(fur~2~ : :
. . .
: ~ v1~-2 methoxviminoacetamidolc
omer)
. 15 S~nple of Form I and Eorm III sodium 3-carbamoyl-
; oxymethyl-7~C2-(fur-2-yl)-2~methoxyiminoacetamido~ceph-
3~em-4~carboxylate (~y~ isomer), prepared according to
Method (iii) of Example 7 and Example 9 respectively,
were exposed to moisture (75% relative humidity) for 3
days to give the ~ . The IR and NMR spectra
of the products conformed to those of an authentic sampleO
Kar~Fischer water analysis gave, respectively, 4~0 and
3,85% (1 mole H20 is equivalent to 3.9%).
'
: 65
~ Z ~ 3
l~ :
a3
isomer)
A suspension of (6R~7R)-3-carbamoyloxymethyl~7-C2-
(fur-20yl)-2-methoxyiminoacetamido]ceph-3-em-4-carboxylic
acid (syn isomer) (4.4g3 in dry methylene chloride (200ml)
was treated with O~t-butyl-N,N'-dicyclohe~ylisourea
(6.6ml), whereby a pale-yello~ solution was formed. After ~ ;
24 hours at 23, starting material remained and more
; isourea (3.3ml) was added. A~ter 48 hours, the mixture
was filtered and the filtrate evaporated under reduced
pressure, The resulting material was slurried with ~ ;
ether/ethyl acetate to remove remaining dicyclohexylurea,
:: ~
The filtrate was washed with saturated aqueous sodium
ydrogen carbonate and water, and then was dried and
evaporated to give a foam (5.2g), Chromatography on
silica gel with toluene:ethyl acetate = 2:I as solvent
gave the ~ (3.9g~ as a pale-yellow foam, ~ ,
~max (ethanol) 275~5nm (e 18j400).
IR and NMR data confirmed the structure as tha~
of the title compound.
; - 66
, .. . ,~ .. , .. . ~ ,
~57283
b) t-Butyl (lR,6R lR)-3-Carbamoylox~methYl-7~ ~ -(fur-
2~ methoxyimlnoacetamidolce~h-3-em-4-carbox~ ate 1-
t-Butyl hypochlorite (0.3ml) was added to a ~:
vigorously stirred solu~ion of t-butyl (5R,7R)-3- .
carbamoyloyloxymethyl-7-[ 2-(fùr-2-yl)-2-methoxyimino-
acetamido]ceph-3-em-4-carboxylate (0.98g) in pyridine
(25ml) and water (lml) at -45. After stirring for
~ - 2 minu~es, 2N sulphurous acid (l ml) was added to the .
.; 10 solution and the mixture was immedi~tely poured into .
20% ~/v 2queous orthophosphoric acid (lOOml). The solution
.. was .extracted ~ith ethyl acetate (2xlOOml), and the
: combined organic extracts were w.qshed with aqueous NaHC03 ~:
(lQOml), and ~ater (lOOml), and were then dried (MgS04) and
. concentrated in vacuo.
The crude product was chromatographed on silica --
gel prepar~tive pl~tes, using ethyl acetate as e~ùant9 the
i. .
minor component of S-oxide running ahead of the R-oxide.
~ Extr~ction of the slower component wit~ ethyl acetate
yielded the title compound (0.27g, 27%).
IR and NMR data confirmed.the structure as.that
o~ the ti~e compound.
6~ ;
,~
,
.
~a ;.
J
''' ';, . ' ' ' ' , ' ' '' ' ' . ' '' "' ' ; ,. ,','"~ ' . ',' ' ' '~ ~ '
i7;~83
c) (lRt6R27R)-3-Carbamoyloxymethyl-7-~2-(fur--2-y~
2^methoxyiminoace~midolc ~ ar,boxyl~c Acid l-Oxide
)
; t-Butyl (lR,6R,7R)-3-carbamoyloxymethyl-7-[2-(fur-2-yl)~2-methoxyiminoacetamido~ceph-3-em-4-carboxylate
l-oxide (syn isomer) (0.42g) was dissolved in
trifluoroacetic acid (5ml~ and stirred at room temperature
- for 8 minutes. The solution was evaporat~d to a red oil
in vacuo, dissolved in ~thyl acetate:acetone (1:1, 5ml) :~
and added dropwise with stirring to petroleum ether
(60-80, 50ml). The deposited ~olid was collected and
dried ;n a desiccator. The crude product was slurried ~;~
with ethyl acetate, and the liquid phase~as decanted and
.
added d-ropwise to petroleum ether (60-80, 59ml), yielding
the title com~ound as a colourless solid (150mg, 40%),
ma (0.25N NaHCO3) 263.5 ( 15,000) and 281nm (~ 13,700);
vmax (Nujol) 1,799 (~-lactam), 1725 and 1716 ~COOH-and
OCO~H2), 1684 and 1538 (CONH) and 1060 and 1050cm 1
(S-~O);I(Me250-d6) values include 0.02 (d, J8Hz, CONH),
4.17(dd, J4 and 8Hz9 7-H), 4.99 (d, J4Hz, 6-H) and 6.09
` (s, N-OCH3).
: '
,:
- 1 .
, . . . . . . .
. . .
. . . . . :
-
. ,~, ~a~
~)
S To a stirred solution of sodium (6R,7R)-3-
carbamoyloxymethyl-7-~2-(fur~2-yl)-2-methoxyiminoacetamido]
ceph-3-em-4-carboxylate (~ isomer) (2.59g) in water
(25ml) was added sodium metaperidoate (1.93g). The
solution was stirred for 30 minutes at ambient temperature
and then acidified by the dropwise addition of 2N aqueous
; hydrochloric acidO The resulting precipitate was collected~
- washed successively with water, ethanol and ether and
then dried in vacuo to afford the ~ as a
` white powder (1.63g.)~ c~]2 + 113 (c 0.86,` Me2S03~ ~m
(pH6 bufer~264~5 (~ 17,200j and 279nm (~ 15,600j;
vmax (Nujol) 1770 (~-lactam), 1740 and 1716(C02H), 1688,
1654, 1589 and 1530 (CONH and OCONH2) and 1030cm (S-~O),
; ~(Me2SO-d6)0.60 (d, J 8Hz, NH), 2.11, 3 19, 3.31
(multiplets, furyl protons), 4.08 (q~ J5 and 8Hz, C-7H). '
4.87 and 5.45 (ABq, J13Hz~ CH20CONH2), 4.96(d, J 5Hz,
C-6H), 5 08 (s, OCH3), 6~10 and 6 42(ABq~ J 18H~, C-2 CH2).
' ', :
., ' .
':'
, ~
~5~Z~3
'
.
.
.~
A solution of sodium periodate (1.93g~ in water
(lOml) was added to a stirred solution of sodium (6R~7R)-
3-carbamoyloxymethyl-7~C2-(fur 2-yl)-2-methoxyiminoacetamido]
ceph-3-em-4-carboxylate (2059g) in water (25ml). Stirring
: - was continued for 30 minutes at room temperature and the
solution was then acidified with 2N HCl (2ml)~ The
deposited lS-oxide was filtered off, washed with ethanol
(5ml) and ether (20ml) and dried in a desiccator, yielding
1.55 g of colourless solid, Ca]D+ 110 (c 1, Me2SO),
i resembling the product described in Example 11.
~ 15 The mother liquors were saturated with sodium
chloride and filtered, and the filtrate was extracted with
ethyl acetate (2xlOOml)~ The organic extracts were com-
bined, dried (MgS04) and concentrated in vacuo, yielding
a yellow solid The crude product was washed wi~h acetone :~
and the insoluble material was removed by filtration.
The filtrate was evaporated to dryness and the acetone
washing repeated yielding 380mg of the lR-oxide, Ca]D- .
88 (c 1, Me2SO)~ ~ (Me2SO-d6j values similar to those
reported in Example 10.
- 70
.
: . - ' '' .
.
3S7~Z~33
C) EX~MPLES OF Ph:R ~ :~D~ICAl LUIP~IION~
Example A
The sterile sodium (6R, 7R)~3-carbamoyloxymethyl-7
C2-(fur-2-yl)-2-methoxyiminoacetamido]ceph-3-em-4-carboxy~
late(~y~ isomer) is illed into glass vials, the claimed
contents of each container being 500 mg and 1.00 g of the
cephalosporin compound~ Filling is carried out aseptically ~-
under a blanket of nitrogen~ The vials are closed us~ng
rubber discs or plugs held in position by aluminium
sealing rings, thereby prevent:ing gaseous exchange or
ingress o~ micro-organisms~ The product-is intended for
reconstitu~ion with Water for Injections or other suitable
sterile vehicle shortly bef~e administration.
~e~
Intram~mm ~ )
Sodium (6R, 7R)-3-carbamoyloxymethyl-7-C2-(fur-2-yl~-
2-methoxyiminoacetamido3ceph-3-em-4-carboxylate
(~y~ isomer) 8.33
Vehicle to: 100.00
Vehicle: Tween:60 3.00
White Beeswax 6.00
Arachis Oil 91~00
-~ The word "Tween" is a trade mark.
-~ ~ 71
.... . . .. . .
.... . . . . . . ..
7 ~ ~ 3
The last three ingredients are heated together at
150 for one hour and then cooled to room temperature with
stirring. The ~terile antibiotic,inely powdered, is
added aseptically to this vehicle and the product refined
with a high speed mixter. The preparation is filled
aseptically into sterilecollapsible aluminium tubes with
: a fill weight of 3.0 g, each tube containing 250 mg of
the cephalosporin compound. The product is intended ~or
a~minis~ration into the mammary gland through the teat ::
~.anal.
.: , ' ~ ' .' .
;, ' ' ' , ~
- ' ,~ ;
, , ~ .. . .
' ~ ~
-
' " , ' .
" :
~, ', ' ' .
3~,' ' `~1~ . .
: : , . . . . . .
,. , , , : , : , ,~'
