CA1157013A - Process for the preparation of (substituted)-2- carbamoyloxymethylpenam and (substituted)3- carbamoyloxycepham - Google Patents

Abstract

ABSTRACT

Penicillin sulfoxide ester are reacted with an iso-cyanate to produce the corresponding (substituted)-2-carbamoyl-oxymethyloeban, the corresponding (substituted)-3-carbamoyl-oxycepham or the corresponding 3-methylcephem. The 6- or 7-side-chain of these products may be cleaved to give the corresponding 6-amino (penams) or 7-amino (cephams and cephems) compounds, and the latter may be reacylated to produce different 6-acyl-2-carbamoyloxymethyl penams, 7-acyl-3-carbamoyloxy cephams and 7-acyl-3-methylcephems. The substituent groups may be removed from the (substituted)-2-carbamoyloxypenams or the (substituted)-3-carbamoyloxycephams to give the corresponding free 2-carbamoyloxymethylpenams or 3-carbamoyloxycephams, respectively. Novel penams and cephams provided by the present invention (after removal of the carboxyl-protecting group to produce the free acid) are active against various Gram-positive and Gram-negative organisms and, accordingly, are useful antibacterial agents for the treatment of diseases caused by such organisms in animals, including man.

Description

~L~S7~313 Detailed Descrle~_on This invention relates to ~-lactam antibiotics. More specifically, it relates to the reaction of a penicillin sulfoxide with an isocyanate to produce the corresponding

2-carbamoyloxymethylpenam, the corresponding 3-carbamoyloxy-cepham or the corresponding 3-methylcep~em. In another aspect, this invention relates to the cleavage of the above products to produce the corresponding compounds having a free amino group in t~e 6-position (penams) or 7-position (cephams and cephems), and to the acylation of the free amino groups of these latter compounds to produce still different 6-acyl-2-carbamoyloxymethylpenams, 7-acyl-3-car~amoyloxycephams and 7-acyl-3-methylcephem3.
The reactions may be better visualized by referenca to the following general reaction schemes.

R2/ ~H3 ~ CO) oOR4 (I) (II) Rl R3 CH20CNHR Rl R3 S

\ N ~ ~ H3 d R ~ 6 ,O COOR O ~ ~ OCNHR
COOR
(III) (IV) .., ' Rl R3 base N ~ ~
III or IV ~ O ~ CH3 (V) cleavage > H2N ~ ~ CH3 , 7 O COOR
(VI) cleavage H2 ~ OCNHR6 (VII) cleavage ~ ~S ~

V ~ H2Nt~ 1 ~ ~ 7CH3 COOR
(VIII) acylation R3 S CH20CNHR6 VI _ > R -CN ~ ~ CH3 o~N '''CooR7 (IX) ~7~3 o ~3 acylation > R8-CNH;; ~ ~HR6 IX) ylat~on 8 11 ~ S ~

O ~ C~3 CooR7 (XI) In the above general reaction schemes, Rl is hydrogen and R2 i5 an amino-blocking group or a conventional acyl group known in the penicillin or cephalosporin art, or Rl and R2, taken together with the nitrogen to which they are attached, may form a phthalimido group, a succinimido group or a group of the formula Rll o R12_~; N--R?<Rl o ~ ~7~13 in which R and R are (lower)alkyl, R is 1,4-cyclo-hexadienyl, substituted or unsubstituted phenyl, or a substituted or unsubstituted heterocyclic group containing one or more hetero atoms such as sulfur, oxygen and/or nitrogen, e.g. thienyl, furyl, tetrazolyl, thiazolyl or thiadiazolyl; and R12 is hydrogen, an aldehydo group or a nitroso group;

R3 is hydrogen, tlower)alkoxy, (lower)alkylthio or R13~H- in which ~13 is substituted or unsubstituted (lower)-OH
alkyl or aryl;
-CooR4 is a protected carboxyl group or a derivative o a carboxyl group;

R5 is an acyl group, a thioacyl group, a substituted sulfonyl, sulfinyl or sulfenyl group, or a substituted metal or non-metal atom having a valence of from 2 to 5;

n is an integer of from 1 to 4;

R6 is hydrogen, is the same as ~5, or is ~;i7~13 ~Coil2c~\ 2 COOR

-R5 (XII) \ O ~_N/

COO~

in which Rl, R2, R3 and R7 are as defined above, and a and b are the same or different and represent an integer ~rom O to n-1, wherein n is as defined above, provided that the sum of a and b is not greater than n-l;

R7 's hydrogen or the same as R4; and R -C- is a conventional acyl group known in the penicillin and cephalosporin art.

:`
:

~. -6-i' ~57~3 In this divisional application the invention provides a process for the preparation of a compound of the formula ~ N ~ S

- 0 ~ ~ CH

wherein ~1 is hydrogen and ~ 2 is hydrogen, an amino-protecting group or an acyl group; or Rl and R2, taken together with the nitrogen to which they are ~ttached, form a phthalimido group, a succinimido group or a group of the formula R12_ ~ N
/\

in which R9 and R10 are (lower)alkyl, Rll is 1,4-cyclo-hexadienyl, substituted or unsubstituted phenyl, or a ~ubstieuted or unsubstituted heterocyclic group, and nl2 i5 hydrogen, an aldehyde group or a ni~roso group;

; -6(a)-~5~ 3 R3 is hyd~ogen~ (lower)alkoxy, (lower)alkylthio or R13C~ (OH) ;~ in which R13 is substi~u~ed s:)r u:nsubsti~uted ~lower)alkyl, or substituted or unsubstituted aryl; and ~ OOR is ~COOHo a pro~ected ~:arbos:yl group or a desivative of a ~arboxyl group;
which procass comprise~ rea ting a compou~d of th~ fDrmula R ~ 3 ~OOR

in ~hich Rl, R2 and ~3 ~re as deflned a~ove and coo~4 iB a protec ted c~rboxyl group or ~ d erivative of a carbo~;yl group;
at a tem~erature up to about 200 g in {~ lnert organic sol~ent, ~ith ~t lea~t an equi~olar amount of an lsocyans,te of the ~os7nula R5 ~NCO )n dh~rein ~5 ~ an a~yl group, a thioacyl group, a ~ub~tituted ~ulfonylg sul~inyl or ~ enyl group~ or a ~ub tituted metal or ~on-met~l atom ha~ring a valence ~ frola 2 to 5, ~nd n is an int~ger o~ 1 to 4; in tAe presence of ~n organic bl~e or an inorganlc lbase ~rhich ~s ~oluble ln the organic ~olv~nt, OEt an ~lkalisle pH; and, lf P~7 is not hydrogen, optlon~lly conYerting GoOR7 to a carbo~l grou~ by a conventlonal oetbod .

-6 (b)-i7~3~3 The isocyanates of Formula II, above, include, for e~ample, those of the following formulae.

(a) W2 M2 NCO

in which ~2 is a divalent metal or non-metal atom (and preferably sulfur or selenium) and ~2 is a substituted or unsubstituted alkyl, aryl or aralkyl group, or an isocyanate group. Examples of isocyanates falling within this class are trichloromethylsulfenyl isocyanate, di~hloromethylsulfenyl isocyanate, trifluoromethylsulfenyl isocyanate, difluoro-methylsulfenyl isocyanate, 2,4- dinitrophenylsulfenyl isocyanate, sulfenyl diisocyanate, selenium diisocyanate, chloromethyl selenium isocyanate, dichloromethyl .qelenium isocyanate trichloromethyl selenium isocyanate, mono-, di- or trifluoro-methyl selenium isocyanate, and the like.

W3 ~
(b) ~ M3-NCO
x3 in which M3 is a trivalent metal or non-metal atom, ~3 and X3 are the same or different and represent a substituted or unsubstituted (lower)alkyl, aryl, ar(lower)alkyl, cycloalkyl, (lower)alkoxy, aryloxy, ar(lower)alkoxy, (lower)alkylthio, or ar~lower)alkylthio group, or an isocyanate group; or W3 and X3, taken together with ~13, r~present a ring system.
Examples of isocyanates falling within this class are phosphorous triisocyanate, boron trlisocyanate, antimony triisocyanate, aluminum triisocyanate, (C4Hg)2BNCO, (C2H~)2~lNCO, C4HgB(NCO)2, C2H5Al(NC0)2, (C6H~)2PNCO, ~57~3 (C H 0)2BNCO, (C6H5CH20)2PNCO, (C2~5S)2P , 3 2 Clcx2c~2op(NcO)2~

¦ P -NCO , CH -O ~
CH2 -O / 1 ~P -NCO

~( CH2~ [~C

and the like.

w4 \
(c) X4/ M4 NC~

in which M4 is a tetravalent metal or non-metal atom, W4, X4 and Y4 are the same or different and represent a substituted or unsubstituted llower)alkyl, aryl, ar(lower)-alkyl, cycloalkyl, (lower)alkoxy, aryloxy, ar(lower)alkoxy, (lower)alkylthio, or ar(lower)alkylthio group, or an isocyanate group; or W4 and X4, taken together with M4, i represent a ring system; or W4, X4 and Y4, taken together with M4, represent a ring system other than phenyl or substituted phenyl; or W4 and X4, taken together, represent : =0, -S or =NW4. Examples of isocyanates within this class are:

',`

7~3 (1) acyl isocyanates and thioacyl isocyanates such as acetyl isocyanate, mono-, di- or trichloroacetyl isocyanate, mono-, di- or trifluoroacetyl isocyanate, propionyl and butyryl isocyanates and their chlorinated or fluorinated analogs, phenylacetyl isocyanate, cyanoacetyl isocyanate, benzoyl isocyanate, p-nitrobenzoyl isocyanate, 2,4-dinitxo-benzoyl isocyanate, benzyloxycarbonyl isocyanate, p-nitro-benzyloxycarbonyl isocyanate, methoxycarbonyl isocyanate, chloromethoxycarbonyl isocyanate, carbonyl diisocyanate, cyanocarbonyl isocyanate, and the like,as well as their thio analogs, e.g. trichlorothioacetyl isocyanate, chloro-methoxythiocarbonyl isocyanate, and the like;

~ 2) sulfinyl isocyanates of the formula in which Y4 is as defined above;

(3) metal and non-metal tetraisocyanates such as Sn(NCO)4, Se(NCO)4, Ti(NCO)4, Ge(NCO)4, Si(NCO)4, and the like;

(4) substituted metal and non-metal isocyanates of the formula W4a~
X4a ~ M4 - NCO
Y4a in which M4 is as defined above and W4a, X4a and Y4a are the 3ame or different and represent substituted or unsubstituted (lower)alkyl, (lower)alkoxy or (lower)alkylthio; or W4a or 7~3 both r~4a and X4a, may be an isocyanate group; or W4a and X4a, taken together with M4, may represent a ring system.
Examples of isocyanates falling within this class axe (CX3)3SnNCO, ~C~3)3SbNCO, (CH3)3GeNCO, (CH3)3TiNCO, 3 2 ( )2~ (CH3)2Sb~NC0)2, CH3Ti(NCo)3, CH3Ge(NCO) 2 5 3 , (C2H50)3SbNCO, (C2H55)3TiNCO, (c2H~s~3GeNco (ClC2H4)3ShNCO, 1 2 5b'~' f~2 ~ s NCO
C~2__~' NCO , CH2 ~ NCO
and the like;

(5) silyl isocyanates of the formula ~W4)m - Si (NCO)4-m in which W4 i5 as described above and m is an integer of from 1 to 3. Examples of isocyanates falling within this class include trimethylsilyl isocyanate, d~methylsilyl diisocyanate, methylsilyl triisocyanate, trimethoxysilyl isocyanate, triethoxysilyl isocyanate, triethylsilyl isocyanate, diphenylsilyl diisocyanate,dibenzyloxy diisocyanate,triphenylsilyl isocyanate, tribenzylsilyl isocyanate, (ClC2H4)3SiNCO, (ClC2H40)2Si(NC0)2, (C6H50)2Si(N~0)2, CH3 Si - NCO CH3___ _ _,, NCO
C~30 ~ NCO , C2H50~'' ~ NCO

~7~ 3 C2~50 CH3 \

CH3 / SiNCO , C4Hg - SiNCO
C2~50 CH3 and the like; and ~6) ring compounds of the formula ~ 3a\
OC~-C C-NCO

3a / 3a ~C
NCO

in which M3a is nitrogen, boron, phosphorus or antimony.

(d) / M5- NCO

in which ~S is a pentavalent metal or non-metal atom and W5, X5, Y5 and ZS are the same or different and represent a substituted or unsubstituted (lower)alXyl, aryl, aryloxy, (lower)alkoxy, or (lower)alXylthio group, or an isocyanate group; or W5 and X5, taken together with M5, represent a ring system; or W5 and X5, taken together, represent =0 or -S. Examples of isocyanates within this class are (C4H9)3Sb(NC0)2, (CH3)4SbNCO, (ClC2H4)3Sb~NC0)2, ~i7~313 C~30P~NCO)2 ~ P(NC0)3 , ~ P~NC0)2 o CH3 \ IJ C2H5 \ ll Clc2H40P(NC0)2 ~ / PNC0 , / PNC0 CH3 C~H50 CH30 \ S C2H~S \ e O
/ PNC0 , / PNC0 , ~ OP(NC0)2 P(NC0)3 , and the like.

~e) R14 - S - NC0 , in which R14 is a substituted or unsubstituted ~lower)alkyl, aryl, ar(lower)alkyl, cycloalkyl, (lower)alkoxy, aryloxy, ar(lower)alkoxy, (lower)alkylthio, or ar(lower)al~ylthio group, or an isocyanate group. Examples of isocyanates falling within this class are methylsulfonyl isocyanate, chloromethylsulfonyl isocyanate, phenylsulfonyl isocyanate, p-nitrophenylsulfonyl isocyanate, 2,4-dinitrophenylsulfonyl isocyanate, toluenesulfonyl isocyanate, phenoxysulfonyl isocyanate, benzyloxysulfonyl isocyanate, ethoxysulfonyl isocyanate, ethylthiosulfonyl isocyanate, sulfonyl diisocyanat2, and the like.

~L~57i~3 In one preferred embodiment of the invention, in the penicillin sulfoxide ester starting material of ~ormula I, Rl and R2, taken together with the nitrogen to which they are attached, may form a phthalimido group, a succinimido group or a group of the formula Rll o R12~
R9 ~ R

in which R9 and R10 are (lower)alkyl, Rll is 1,4-cyclo-hexadienyl, substituted or unsubstituted phenyl, or a ~ubstituted or unsubstituted heterocyclic group containing one or more hetero atom~ such as sulfur, oxygen and~or nitrogen, e.g. thienyl, furyl, tetrazolyl, thiazolyl or thiadiazolyl, and R12 is hydrogen, an aldehydo group or a nitroso group.

In a more preferred embodiment Rl and R2, taken together with the nitrogen to which they are attached, form a group of the formula Rll o R12_ N N--R9>~Rl O

~57~3 iXI which R9 and R10 are as defin~d above (but preferably are each methyl), R 2 is as defined above (but preferably is hydrogen, and Rll is as defined above tbut preferably i3 1, 4-cyclohexadienyl, phenyl, p-hydroxyphenyl, thienyl, furyl, tetrazolyl, thiazolyl or thiadiazolyl). Most preferably, Rll is phenyl or p-hydroxyphenyl, It is also preferred that R6 be hydrogen.
In another preferred embodiment of the invention, in the penicillin sulfoxide ester starting material of Formula I, R is hydrogen and R is an acyl group of the formula Rl~-(A)r(c~2)s(lH)t (XIV) in which r is O or 1, s i5 an integer of from O to 6, t is O or 1, A is oxygen or sulfur, R16 is amino, substituted amino, acylamino, hydroxy, azido, halogen, carboxy, caxbamoyl, guanidino, sulfo, sulfamino, phosphono, acyloxy, tetrazolyl, carboalkoxy, or the like, and R15 is hydrogen, or a substituted or unsubstituted alkyl, aryl, aralkyl,cycloalkyl, heterocyclyl or heterocyclylalkyl group.
In a more preferred ~ bodiment, the acyl group of Formula XIV has the structure O
R15 C- (XV) in which R15 is as defined a~ove. Group R 5 may be unsubstituted or may be substituted by such groups as OH, Sll, SR (where R
is alkyl or aryl), alkyl,alkoxy, aryl, halo, cyano, carboxy, nitro, sulfoamino, carbamoyl, sulfonyl, azido, amino, substituted amino, haloalkyl, carboxyalkyl, carbamoylalkyl, 7~3 N-csubstituted carbamoylalkyl, guanidino, N-substituted guanidino, guanidinoalkyl, or the like. Examples of su:Ltable acyl groups of Formula XV are those in which R15 ic~ benzyl, p-hydroxybenzyl, 4-amino-4-carboxy~utyl, methyl, cyanomethyl, n-amyl, n-heptyl, ethyl, propyl, isopropyl, 3- or 4-nitrobenzyl, phenethyl, ~,B-diphenyl-ethyl, methyldiphenylmethyl, triphenylmethyl, 2-methoxy-phenyl, 2,6-dimethoxyphenyl, 2,4,6-trimethoxyphenyl, 3,5-dimethyl-4-isoxazolyl, 3-butyl-5-methyl-4-isoxazolyl, 5-methyl-3-phenyl-4-isoxazolyl, 3-(2-chlorophenyl)-5-methyl-4-isoxazolyl, 3-(2,6-dichlorophenyl)-5-methyl-4-isoxazolyl, 2- or 3- (5-methylthienyl)methyl, D-4-amino-4-carboxybutyl, D-4-N-benzoylamino-4-carboxy-n-butyl, p-amino-benzyl, o-aminobenzyl, m-aminobenzyl, (3-pyridyl)methyl, 2-ethoxy-l-naphthyl, 3-car~oxy-2-quinoxalinyl, 3-(2,6-dichloro-phenyl)-5-(2-furyl)-4-isoxazolyl, 3-phenyl-4-isoxazolyl, 5-methyl-3-(4-quanidinophenyl)-4-isoxazolyl, 4-guanidinomethyl-phenyl, 4-guanidinomethylbenzyl, 4-quanidinobenzyl, 4-guanidinophenyl, 2,6-dimethoxy-4-guanidinophenyl, o-sulfobenzyl, p-carbcxymethylbenzyl, p-carbamoylmethylbenzyl, m-fluorobenzyl, m-bromobenzyl, p-chlorobenzyl, p-methoxy~enzyl, l-naphthyl-methyl, 3-isothiazolylmethyl, 4-isothiazolylmethyl, 5-iso-thiazolylmethyl, 4-pyridylmethyl, 5-isoxazolylmethyl, 4-methoxy-5-isoxazolylmethyl, 4-methyl-5-isoxazolymethyl, l-imidazolyl-methyl, 2-benzofuranylmethyl, 2-indolylmethyl, 2-phenylvinyl, 2-phenylethynyl, 2-(5-nitrofuranyl)~inyl, phenyl, o-methoxy-phenyl, o-chlorophenyl, o-phenylphenyl, p-aminomethylbenzyl, 1-~5-cyanotriazolyl)methyl, difluoromethyl, dichloromethyl, dibromomethyl, 1-(3-methyllmidazolyl)methyl, 2- or 3-(5-carboxymethylthienyl)methyl, 2-- or 3-(4-car~amoylthienyl)methyl, ~ 57~3 2-- or 3-(5-methoxythienyl)methyl, 2- or 3-(4-chlorothienyl~-methyl, 2- or 3-(5-sulfothienyl~methyl, 2- or 3-(5-carboxy-thienyl)methyl, 3-(1,2,5-thiadiazolyl)methyl, 3-(4-methoxy-1l~2,5-thiadiazolyl)methyl, 2-furylmethyl, 2-(5-nitrofuryl)-methyl, 3-furylmethyl, 2-thienylmethyl, 3-thienylmethyl, tetrazolylmethyl, cyclopentyl, cyclohexyl, cycloheptyl cyclohexylmethyl, cyclohexylpropyl, dihydrobenzyl, dihydro-phenylmethyl, tolylmethyl, xylylmethyl, te~rahydronaphthyl-methyl, piperazinylmethyl, pyrrolidiny~methyl, benzothiazolyl-methyl, benzoxazolylmethyl, and lH (or 2H)-tetrazolylmethyl.

In another more preferred embodiment, the acyl group of Formula XI~ has the structure o R15A(CH2)sC- (XVI) wherein R15, A and s are as defined above. Examples of suitab}e groups of the formula R15AtCH2)~- include methoxy-methyl, methylthiomethyl, cyclohexylthiomethyl, cyclohexyloxy-methyl, dihydrophenoxymethyl, dihydrophenylthiomethyl, cyclo-pentyloxy, cyclohexyloxy, dihydrophenoxy, benzyloxy, xylyloxy, tolyloxy, naphthoxy, phenylthiomethyl, butylmercaptomethyl, allylthiomethyl, 2-furyloxy, 8-quinolyloxy, pyridylmethoxy, trichloroethoxy, l-cyclopropylethoxy, p-nitrobenzyloxy, o-chlorobenzyloxy, o-nitrobenzyloxy, p-methoxybenzyloxy, 3,4-dimethoxybenzyloxy, a-chlorocrotylmercaptomethyl, phenoxy-methyl, phenoxyethyl, phenoxybutyl, phenoxybenzyl, diphenoxy-methyl, dimethylmethoxymethyl, dimethylbutoxymethyl, dimethyl-phenoxymethyl, 4-guanidinophenoxymethyl, 4-pyridylthiGmethyl, p-~carboxymethyl)phenoxymethyl, p-(carboxymethyl)phenylthio-methyl, 2-thiazolylthiomethyl, p-(sul~o)phenoxymethyl, ~57~3 p (carboxy)phenylthiomethyl, p-5carboxymethyl)phenoxymethyl, p~-(carboxymethyl)phenylthiomethyl, 2-pyrimidinylthiomethyl, phenethylthiomethyl and l-(5,6,7,8-tetrahydronaphthyl)-oxomethyl.

In another morP preferred embodiment, the acyl group of Formula XIV has the structure Rl CH-C- (XVII) l16 wherein R15 and R16 are as defined above. Examples of suitable groups of the formula R15_c~_ include a-aminobenzyl, a-amino-2-thienyl, a-methylamino-benzyl, a-amino-methylmercaptopropyl, a-amino-3- or 4-c~lorobenzyl, a-amino-3 or 4-hydroxybenzyl, -amino-2,4-dichlorobenzyl, aoamino-3,4-dichlorobenzyl, ~(-)-a-hydroxy-benzyl, a-carboxybenzyl, a-amino-3-thienyl, a-aminO-2-thienyl, D-(-)-a-amino-3-chloro-4-hydroxybenzyl, D(-)-a-amino-3-thienyl, l-aminocyclohexyl, a-(5-tetrazolyl)benzyl, 2-(a-carboxy)thienylmethyl, 3-(a-carboxy)furylmethyl, a-sulfaminobenzyl, a-sulfamino-3-thienyl, a-(N-methylsulfamino)-benzyl, D(-)-a-yuanidino-2-thienyl, D(-)-a-guanidinobenzyl, a-guanylureidobenzyl, a-hydroxybenzyl, a-azidobenzyl, a-fluoro-benzyl, 4-(5-methoxy-1~3-oxadiazolyl)-amlnCmQthyl~ 4-(5-methoxy-1,3-oxadiazolyl)-hydroxymethyl, 4-(5-methoxy-l~3-oxadiazolyl) carboxymethyl, 4-t5-methoxy-1,3-sulfadiazolyl)-aminomethyl, 4-~(5-methoxy-1,3-sulfadiazolyl)-hydroxymethyl, 4-(5-methoxy-1,3-sulfadiazolyl)-carboxymethyl, 2-(5-chlorothienyl)-amino-methyl, 2-(5-chlorothienyl)-hydroxymethyl, 2-(5-chlorothienyl)~
carboxymethyl, 3-(1,2-thiazolyl)-aminomethyl, 3-(1,2-thiazolyl)-hydroxymethyl, 3-(1,2-thiazolyl)-carboxymethyl, ~-(1,4-thiazolyl)-aminomethyl, 2-(1,4-thiazolyl)-hydroxymethyl, 2-(1,4-thiazolyl)-carboxymethyl, 2-benzothienylaminomethyl, 2-benzothienyl-hydroxymethyl, 2-benzothienylcarboxymethyl, a-sulfobenzyl, and a-phosphonobenzy~

I~ the acyl group contains a functional group, such as amino, hydroxy, mercapt~ or carboxy, the functional group may be protected with an appropriate protective group.
Because the acyl side-chain may subsequently be cleaved to produce the free amino compound (which may, if desired, be re-acylated with a different side-chain), it is not always necessary to protect reactive substituent groups in the side-chain.

Suitable protective groups for the amino radical include any of the conventional protective groups such as those acyl groups which can easily be split off (e.g. trichloroethoxy-carbonyl, benzyloxycarbonyl, p-toluenesulfonyl, p-nitrobenzyl-oxycarbonyl, o-chlorobenzyloxycarbonyl, o-nitrophenylsulfenyl, chloroacetyl, trifluoroacetyl, formyl, tert-butoxycarbonyl, p-methoxybenzyloxycarbonyl, 3,4-dimethoxybenzyloxycarbonyl, 4-phenylazobenzyloxycarbonyl, 4-(4-methoxyphenylazo)benzyloxy-carbonyl, pyridine-l-oxide-2--methoxy-carbonyl, 2-pyridyl-~ 18-;7~3 methoxycarbonyl, 2-furyloxycarbonyl, diphenylmethoxycarbonyl, l,1-dLmethylpropoxycarbonyl, isopropoxycarbonyl, l-cyclo-pxopylethoxycarbonyl, phthaloyl, succinyl, 1-adamantyloxy-carbonyl or 8-quinolyloxycarbonyl), or other radicals which can easily be split off (e.g. trityl, 2-nitrophenylthio, 2,4-dinitrophenylthio, 2-hydroxybenzylidene, 2-hydroxy-5-chlorobenzylidene, 2-hydroxy-1-naphthylmethylene, 3-hydroxy-4-pyridylmethylene, 1-methoxycarbonyl-2-propylidene, l-ethoxy-carbonyl-2-propylidene, 3-ethoxycarbonyl-2-butylidene, l-acetyl-2-propylidene, 1-benzoyl-2-propylidene, 1-[N-(2-methoxyphenyl)-carbamoyl]-2-propylidene, 1-[~-(4-methoxyphenyl)carbamoyl~-2-propylidene, 2-ethoxycarbonylcyclohexylidene, 2-ethoxy-carbonylcyclopentylidene, 2-acetylcyclohexylidene, 3,3-dimethyl-5-oxocyclohexylidene, or mono- or bis-trialkylsilyl). Other coAventional amino protecting groups such as those described in ~Protective Groups in Organic Chemistry, n J. F . W. McOmie, Ed., Plenum Press, New York, ~ew Yor~, 1973 Chapter 2, shall be recognized as suitable.

Suitable protective groups for the hydroxy or mercapto groups include any of the conventional protective groups for hydroxy or mercapto groups such as the acyl groups which can be easily split off ~e.g. benzyloxycarbonyl, 4-nitrobenzyloxy-carbonyl, 4-methoxybenzyloxycarbonyl, 3,4-dLmethoxybenzyloxy-carbonyl, 4-phenylazobenzyloxycarbonyl, 4-~4-methoxyphenylazo~-benzyloxycarbonyl, tert-butoxycarbonyl, 1,l-dimethylpropoxy-carbonyl, isopropoxycarbonyl, l-adamantyloxycarbonyl, l-cyclopropylethoxycarbonyl, 8-quinolylethoxycarbonyl, 2,2,2-trichloroethoxycarbonyl, 3-iodopropoxycarbonyl, 2-furfuryloxy-carbonyl, 8-quinolyloxycarbonyl and trifluoroacetyl) and those protecting groups other than acyl groups which can be easily split off, such as benzyl, trityl, methoxymethyl, 2-nitrophenylthio and 2,4-dinitrophenylthio. Other conventional hydroxy and mercapto protecting groups, including those described in ~rotective Groups in Organic Chemistry~, supra, Chapters 3 and 7, shall be considered as suitable.

The protective group for the car~oxy group may be any of those conventional protective groups used for protecting a carboxy group, e.g. an ester group such as methyl, ethyl, propyl, isopropyl, tert-butyl, butyl, benzyl, diphenylmethyl, tri~henylmethyl, p-nitrobenzyl, p-methoxybenzyl, benzoylmethyl, acetylmethyl, p-nitrobenzoylmethyl, p-chlorobenzoylmethyl, p-methane~ulfonylbenzoylmethyl, phthalimidomethyl, trichloro-ethyl, 1,1-dimethyl-2-propynyl, acetoxymethyl, propionyloxy-methyl, pivaloyloxymethyl, 1,l-dimethylpropyl, 1,l-dimethyl-2-propenyl, 3-methyl-3-butenyl, succinimidomethyl, l-cyclo-propylethyl, 3,5-di(tert)butyl-4-hydroxybenzyl, methyl-sulfenylmethyl, phenylsulfenylmethyl, methylthiomethyl, phenylthiomethyl, dimethylaminomethyl, 2-methoxquinoline-1-oxide, 2-methylpyridine-1-oxide, chlorooxalyl or di(p-methoxy-phenyl)methyl ester, the silyl ester groups derived from a silyl compound such as dimethyldichlorosilane twhich have been reported in U. S. Patent 3,944,545, in Japanese Patent Application No. 7332/1971 laid open to public inspection under No~ 7073/1971 and in Netherlands Patent Application laid open to public inspection under No. 7,105,259), and metallic or non-metallic derivatives of the carboxy group derived from such compounds as boron trichloride, ~C2H5)2AlCl, ~C~3O)2PCl and the like ~hich have been disclosed in U. X. Patent 1,409,415. Other known conventional carboxyl protecting groups such as those described in "Protective Groups in Organic Chemistry", supra, Chapter 5, shall be recognized as suitable.

In compound I, above, -COOR is defined as a protected carboxyl group or a derivative of a carboxyl group. Suitable car~oxyl-protecting groups are well known in the art, and include those listed above for protecting carboxyl substituents on the acyl side-chain. R4 also may be a metallic or non-metallic derivative such as described above for protecting carboxyl substitutents. The group -CooR4 preferably is (1) an ester: a silyl ester such as referred to above, an alkyl or alXenyl (e.g.~ methyl, ethyl, propyl, isopropyl, butyl, tPrt-~utyl, cyclohexyl, cycloheptyl, vinyl, l-propenyl, 2-propenyl or 3-butenyl) ester, aryl (e.g., phenyl xylyl, tolyl or naphthyl) ester, aralkyl (e.g., benzyl or diphenylmethyl) ester, or an ester wherein one of the car~on atoms of the alkyl group is replaced with a nitrogen, sulphur or oxygen atom, or by a carbonyl group, such as methoxymethyl ester, ethoxymethyl ester, methylthioethyl ester, methylthiomethyl ester, dimethylaminoethyl ester, diethylaminoethyl ester, phenoxymethyl ester, phenylthiomethyl ester, methylsulfenyl-methyl ester, phenylsulfenyLmethyl ester, benzoylmethyl ester or toluoylmethyl ester, or an ester containing one or more appropriate substituents (e.g., halogen, alkoxy, alkanesulfonyl or phenylazo) such as chloromethyl ester, bromomethyl ester, ~7~3 trichloroethyl ester, cyanomethyl ester, p-nitrophenyl ester, 2,4,5-trich}orophenyl ester, 2,4,6-trichlorophenyl ester, pentachlorophenyl ester, p-methylsulfon~lphe~l estar, 4-phenylazophenyl ester, 2,4-dinitrophenyl ester, p-chlorobenzyl ester, o-nitrokenzyl ester, p-methoxybenzyl ester, ponitrobenzyl ester, 3,4,5-trimethoxybenzyl ester, bis~p-methoxyphenyl)methyl ester, pentachlorobenzyl ester, trichlorobenzyl ester, 3,5-dittert)butyl-4-hydroxybenzyl ester, p-nitrophenylthiomethyl ester, p-nitrobenzoylmethyl ester or p-chlorobenzoylmethyl ester, or an ester formed from a thioalcohol, a substituted thioalcohol, N-hydroxysuccinimide, N-hydroxyphthalimide, tetrahydrofuran, l-cyclopropylethanol, l-phenyl-3-methyl-5-pyrazolone, 3-hydroxypyridine, 2-hydroxymethylpyridine-1-oxide, l-hydroxy-2(1~)-pyridine, dimethylhydroxyamine, diethylhydroxyamine, glycolamide, 8-hydroxyquinoline, 2-hydroxymethylquinoline-l-oxide, methoxyacatylene, ethoxyacetylene, tert-butylethynyldimethylamine, tert-butylethynyldiethylamine, ethylethynyldiethylamine or 2-ethyl-5-(3-sulfophenyl)isoxazolium hydroxide inner salt;or (2) an acid amide: an N-al~yl acid amide (e.g., N-methyl acid amide or N-ethyl acid amide), N,N-dialkyl acid amide (e.g., N,N-dimethyl acid amide, N,~-diethyl acid amide or N-methyl-N-ethyl acid amide), or an acid amide with Lmidazole, benzotriazole, a 4-substituted imidazole or a protected tetrazole.

Other known conventional carboxy protecting groups such as those described in nProtective Groups in Organic Chemistry", supra, Chapter 5, shall be recognized as suitable.

The reaction of the penicil}in sulfoxide (I) with thle isocyanate (II) is conducted in an inert organic solvent such as dioxane, toluene, xylene, benzene, tetrahydrofuran, methyl isobutyl ketone, 1,2-dichloroethane, methyl chloroform or the like. The reaction may, if desired, be conducted in excess isocyanata as the solvent. Dioxane is a preferred solvent.

The reaction may be conducted over a wide temperature range, e.g. up to about 200, preferably from about 70 to about 140 and most preferably from about 90 to about 115.
It is most convenient to conduct the reaction at the reflux temperature of a suitably selected solvent.

The reaction time is not critical and may range from 1 hour to 24 hourq, or more, depending on the particular reactants, reaction temperature, etc.. In general, we prefer to conduct the reaction for from about 1 to about 10 hours, and typically from about 3 to about 7 hours.

The penicillin sulfoxide (I~ is reacted with at least one equivalent of the isocyanate (II) and preferably with an excess thereof, Up to about 5 equivalents, or more, of isocyanate may be utilized, but no advantage is obtained by using greater amounts. The isocyanate aids in maintaining an anhydrous reaction medium by scavenging any free water which may be present. We prefer to use from about 2 to 4 equivalents of the isocyanate, and most preferably about 3 equivalents of the isocyanate, per equivalent of the penicillin 3ulfoxide.

If the reaction of the penicillin sulfoxide (I) and the isocyanate (II) is conducted in the absence of a base the product is primarily a mixture of the penam (III) and the ~7~`~3 cepham ~IV), along with a small amount o~ the cephem (V~.
Thle xatio of the penam and cepham in the product may be varied by the use of different isocyanates. Thus, for example, when the p-nitrobenzyl ester of penicillin V
sulfoxide is reacted in dioxane with silicon tetraisocyanate, the product usually consists of 95-98% of the penam and traces of the cepham. ~lowe~er, the reaction of the p-nitrobenzyl ester of penicillin V sulfoxide in dioxane with trichloroacetyl isocyanate gives a product which typically is 30-35~ penam, 60-65% cepham and about S~ cephem. The product mixture may readily be separated into its components by chromatography, e.g. on silica gel.

Penam (III) and/or cepham (IV) may be converted to cephcm (V) by treatment with base, as shown in the general reaction scheme, above. Alternatively, if the cephem (V) is the desired product, the penicillin sulfoxide (I) may be reacted with the isocyanate (II) in the presence of a base to give the cephem (V) directly. When preparing the cephem directly in this manner, we have found that highest yields of the cephem are obtained if a source of bromide ions is also added to the reaction mixture.

When converting penam (III) and/or cepham (IV) to cephem (V) by treatment with base, one may use any organic or inorganic base. The reaction may be conducted in an organic solvent by using a base which is soluble therein or by using a two-phase aqueous-organic solvent system wherein the base is water soluble.

~7C~3 When utilizing a two-phase system for base treat~ent oE the penam and/or cepham, one may utilize any of the ul3ual water-soluble bases, e.g. NaOH, KOH, K2C03, Na2C03, NaHC03, XHC03, an alkaline phosphate buffer, or the like.
When the base treatment is conducted in an organic solvent, one may use any of the usual organic-soluble bases, e.g. a tertiary amine such as triethylamine, pyridine, quinoline, isoquinoline, lutidine, tetramethylguanidine, or the li~e.
We have found that some bases such as X2C03, which are generally considered to be insoluble in organic solvents, appear to have sufficient solubility in certain organic solvents such as dioxane to be utilized in such systems.

Thus, the penam ~III) and/or cepham (rV) ~either as isolated products or as the crude reaction mixture) may be con~erted to the corresponding cephe.~ (V) by adjusting a solution the_eof to an al~aline p~ and maintaining it at a~ al~aline pH for from about 15 minutes to 24 hours, depending o~ the temperature, base, particular reactants and solvent system. The tcmperature is not critical. We find that 0-40 is a convenient range and that 0-25 is preferred.
Higher temperatures may be used but normally decrease the yield of desired product, while lower temperatures require excessively long reaction times.

The base utilized to convert the penam and/or cepham to the cephem need not be added in a stoichiometric amount, as this is merely a catalyst. We have utilized from about 5 to about 150 mole percent of base and prefer to use from about 20 to about 50 mole percent. A greater amount of base may be utilized b~t normally does not increase the yield.

~5~ 3 The use of less than about 5 mole percent of base usually unduly increaRe~ the reaction time and/or yield of product.
The most suitable amount of base depends on the particular penam and/or cPpham being treated, as well as on the particular solvent system.

As indicatsd above, we have found that, in the "one-step" reaction of a penicillin sulfoxide with an isocyanate in the presence of a ~ase to produce the cephem directly, the yield of cephem is normally significa~tly increased by the addition of a source of bromide ions to the reaction mixture. Suitable sources of bromide ion will be apparent to those skilled in the art, and include acetyl bromide, propionyl bromidQ, benzoyl bromide, pyridine hydrobromide, trimethylbromosilane, thionyl bromide, boron tribromide, silicon tetrabromide, aluminum tribromide, tin tetrabromide, and the like. The amount of br ide giving the best yield of cephem will depend on the particular penicillin sulfoxide, isocyanate, base and solvent being utilized. We have found that from about 5 to about 50 mole percent of bromide is adequate while from about 10 to about 30 mole percent is usually preferred.

After reaction of the penicillin sulfoxide with the isocyanate to produce the desired penam (III), cepham (IV) or cephem (V), the latter products will still contain a protected carboxyl group, i.e. R7 is initially the same as R4. It is usually desired ~o remove the protecting group to pr~oduce the corresponding compound containing a free carboxyl group (i.e. R7 is hydrogen). Removal of the carboxyl-~7C~3 protecting group is achieved by conventional treatment, e.g. catalytic hydrogenolysis in the case of the p-nitro-benzyl protecting group. This may be accomplished, for example, by the use of hydrogen in the presence of a catalyst such as palladium or rhodium on a carrier such as char~oal, barium sulfate or alumina. Alternative methods of removal of the protecting group include reaction with Lewis acids such as trifluoroacetic acid, formic acid or zinc bromide in benzene (the reaction with Lewis acids may be facilitated by the addition of a nucleophile such as anisole), or by reduction with agents such as zinc/acetic acid or zinc~formic acid, or by reaction with nucleophiles such as those containing a nucleophilic oxygen or sulfur atom, e.g. alcohols, mercaptans or water.
The side chains of penam (III), cepham (IV) and cephem (V) may, if desired, be clea~ed to give the free 6-amino compound (penam~) or 7-amino compound (cephams and cephems)~ Cleavage may be e~fected by means of enzymes or by chemical hydrolysi~
or hydrogenolysis. If the side chain is to be cleaved, such cleavage preferably is conducted prior to removal of the carboxyl-protecting group. In the chemical hydrolysis of the sidechain, the penam, cepham or cephem is first converted to an imino halide by reaction with a halogenating agent such as phosphorus pentachloride, phosphorus oxychloride, phosgene, thionyl chloride, oxalyl chloride or p-toluenesulfonyl chlorid2 (and preferably phosphorus pentachloride or phosphorus oxychloride) in the pre~ence of an acid binding ` agent. The reaction is conducted in an inert organic solvent such as diethyl ether, nitromethane or a halogenated hydrocarbon ' ~ ~ ~7a~3 ~methylene chloride and chloroform are the preferxed solvents).
It is preferred to use an excess of the halogenating agent (up to about 2 moles per mole of penam, cepham or cephem) and to use from about 1.5 to about 5 moles of acid binding agent per mole of halogenating agent. Suitable acid binding agents are tertiary amines such as triethylamine, N,N-dimethyl-aniline, pyridine, quinoline lutidine, picoline and the like.
The reaction may be conducted at a temperature of from about -60 to -10 for penams and at from about -60 to about +10 for cephams and cephems. We prefer to conduct the reaction at from about -30 to about -40.
The imino halide prepared in the above step is then converted into an imino ether by reaction with a primary or secondary alcohol in the presence of an acid binding agent (this is usually most simply accomplished by conducting this step without isolation of the imino halide). Suitable alcohols include alkanols such as methanol, ethanol, propanol, isopropanol, butanol and isobutanol; aralXanols such as benzyl alcohol and 2-phenylethanol; cycloalkanols such as cyclohexanol;
and alkanedisls such as ethylene glycol and l,6-hexanediol.
The preferred alcohol is methanol. The reaction may be conducted over the same temperature range as in the formation of the imino halide, and preferably is conducted at from about -30 to about -40.
The imino ether is then hydrolyzed to produce the free amino compound. This is most simply accomplished by quenching the solution of the imino ether with watex at a temperature of from about -5 to about +10.

7~3~3 Chemical cleavage of the acyl side-chain, such as described above, alRo will remove some or all of the substituent R on the penam and cepham, depending on the particular nature of R6, the particular halo~enating agent which i8 utilized, the temperature at which the reaction is conducted, the particular work-up procedure, etc.. Thus, with the penam having a phenoxyacetamido side-chain and R6 substituent which ~s trichloroacetyl, PC15 mediated cleavage followed by wor~ up in methanol with a bicar~onate will remove both groups. In such cases (where two acyl groups are being removed~ one should utilize about twice the amount of halogenating agent and alcohol referred to above.
In those cases where little or no R6 group is removed during Ride-chain cleavage, the æmount o~ halogenating agent and alcohol should be in the range stated above. It will be appreciated by those skilled in the art that PC15 side-chain cleavage cannot be utilized on compounds III or rv wherein R6 is hydrogen, since the free carbamoyl group will be destroyed. The side-chain may be removed without r~moving substituent R6 of the penam or cepham (wherein R6 is other than hydrogen) by utilizing specific halogenating agent~
and specific R6 substituents. Similarly, one may ramove the R6 substituent of the penam or cepham without removing the side-chain by utilizing suitable R6 substituents and methods of removal, eOg. if R6 is chloroacetyl, it may be removed with thiourea, without removing the side-chain.
The trichloroacetyl group may be removed by the use of sodi~m bicarbonate in methanol.

Cleavage of the 6- or 7-acyl side-chain in the penam ~III) or cepham (IV~ may be achieved by hydrogenolysis techniques when the side-chain ic a group readily removed ~y such techniques, e.g. p-nitrobenzyloxycarbonvl~

ii7~3~3 When a penicillin sulfoxide ester of Formula I isreacted with an isocyanate of Formula II in which n = 1 (i.e. a monoisocyanate), R6 in the resulting penam (III) or cepham (n) will be the same as R5. If, however, n is greater than 1 (i.e. is 2-4), then the resulting R6 substituent on the penam or cepham may have the structure XII shown above. Thus, if a penicillin sulfoxide e~ter is reacted with, for example, carbonyl diisocyanate, the initially resulting prcduct will be a carbonyl group which is substituted with two penam moieties, with two cepham moieties, or with one penam moiety and 1 cepham moiety, or a mixture of these products. Such bis , tris- and tetrakis-penam or cepham compounds may be utilized in that form ~after removal o~ the carboxyl protecting groups) or they may be split to the mono-substituted compounds either under normal workup .steps or by subsequent procedures.

After cleavage of the side-chains from the penam (III), cepham (IV) or cephem (V) to produce the free amino compounds of Formula VI~ ~II or VIII, the latter compounds may be reacylated with a different side-chain to produce compounds of Formula IX, X or XI. Briefly, a compound of Formula VI, VII or VIII is reacted with an acid of the formula o or with an acylating derivative of said acid, in which o R8-~- is a conventional acyl group known in the psnicillin or cephalosporin art. Such conventional acyl groups include, but are not limited to, those e~emplified above for R2.

~ ~7C~3 In the acylation of a compound of Foxmula VI, VII or VII;I, the carboxylic acid of formula XIII may be used se in which case it is preferred to use an enzyme or a condensing agent. Suitable condensing agents include, N,N-dimethylchloroform~minium chloride, an N,N'-carbonyldiimida-zole or an N,N'-carbonylditriazole, a carbodiimide reagent ~especially N,N'-dicyclohexylcarbodiimide, N,N'-diisopropyl-carbodiimide or N-cyclohexyl-N'-(2-morpholinoethyl)carbodiimide~, a~ alkynylamine rçagent, i~oxazolium salt reagent, ~etenimine reagent, hexachlorocyclotriphosphatriazine or hexabromocyclo-triphosphatriazine, diphenylphosphoryl azide (DPPA), diethyl-phoaphosphorylcyanide (DEPC), diphenylphosphite or rl-eth carbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ).

As an alternative to using the carboxylic acid XIII
in the above process, there may also be employed reactive acylating derivatives of acid XIII, i.e. functional equivalents of the acid as acylating agents for a primary amino group.
Examples of reactive acylating derivatives of the carboxylic acid include the acid halide (e.g. acid chloride or acid bromide), acid anhydrides, including mixed anhydrides (e.g.
alkoxyformic anhydrides), acid azides, active esters (e.g.
p-nitrophenyl) and active thioesters. Another reactive deri-vative of the acid is a corresponding azolide, i.e. an amide of the acid whose amide nitrogen is a member of a quasiaromatic five-membered ring containing at le~st tw-o nitrogen atoms, i.e. imidazole, pyrazole, the triazoles, benzimidazole, benzotriazole and their substituted derivatives. The general method for preparation of azolides is described, for example~
in U. S. Patent 3,910,900.

~ ~7~ 3 Mention was made above of the use of enzymes to couple the free acid with a compound of Formula VI, VII or VIII. Included in the scope of such processes are the use of an ester, e.g. the methyl ester, of that free acid with enzymes provided by various microorganisms, e.g. those described in J Am. Chem. Soc., 94(11), 4035-4037 ~1972), J Antibiotics (Japan), 24(S), 321-323 (1971) and U. S.
Patent 3,682,777.

The acylation process is conducted in a reaction-inert solvent system which can be aqueous or non-aqueous. Suitable reaction-inert solvents include, for example, water, acetone, tetrahydrofuran, dioxane, acetonitrile, dimethylformamide, dimethylsul~oxide, methylene chloride, chloroform, benzene, toluene, methyl isobutyl ketone and mixtures of the above-mentioned organic solvents with water. The choice of solvent, i.e. particularly whether an aqueous or non-aqueous solvent is used, is dependent on the particular starting materials employed. Thus, for example, if the starting compound of Formula VI, VII or VIII is used in the form where the 3- or 4- carboxyl moiety is protected by an ester group cleaved by hydroxylic solvents, e.g. a silyl or stannyl ester, an aprotic organic solvent is most preferably employed. When the starting compound of Formula VI, VII or VIII is used in its salt form, water or an aqueous organic solvent system is preferably employed. The most advantageous solvent system for the particular reagents used can be determined by routine exper~entation.

i7~13 The duration and temperature of the acylation rea,ction are not critical. Temperatures in the range of frc~ about -30C to about +50C are commonly used for reaction times ranging from less than one hour up to a day or more. Although the initial contacting of the reactants is preerably carried out at around 0C to reduce the incident of by-products, it is frequently desirable after a few minutes of mixing to allow the reaction mixture to warm to room temperature until the reaction is complete.

Any of compounds III-XI of this invention, after rem~val of the carboxyl-protecting group R7, may be converted, if desired, to a pharmaceutically acceptable salt or to a physiologically hydrolyzed ester 3uch as the pivaloyloxymethyl, acetoxymethyl, phthalidyl, 5-indanyl or methoxymethyl ester.

A~ shown by the wavy lines in the structural formula for Compound I, the substituents on the 6-position may have either stereochemical configuration, i.e. the amino moiety may have the normal ~ configuration and ~3 the normal a configuration, or these may be reversed. Whatever the configuration at the 6-position of starting Compound I, the same configuration will be maintained in the penam, cepham or cephem product.

~ owever, the configuration of the 2-position of penam III or the 3-position of cepham rv is dependent on the configuration of the sulfoxi~e moiety of starting Compound I.
Thus, as shown in the following equations, the S sulfoxide i7~3i3 (Ia) gives pr~marily the R penam (IIIa) or S cepham (IVa), whi.le the R sulfoxide (Ib) gives primarily the S penam (IIIb) or the R cepham (IVb)~ which readily elLminates to thle cephem.

R2/ ~ CRCR3 + R NCO >

(Ia) [S-sulfoxide]

R1 R3 S CH20CNHR R \ R3 S

R2~ ~ ~ COOR ~ CH3 COOR
(IIIa) [R penam] (Iva) R2 / ~ 3 ~ R5NCo >
COOR
(Ib) lR sulfoxide]

~ ~7 ~1 3 R2/ ~ 4nd R ~ CCU~R6 COOR
(IIIb) ~IYb) [S penaml tR cepham]

Depending on the particular substituent groups on the starting penicillin sulfoxide, small to moderate amounts of the product having the alternate configuration may also be prsduced.
The reaction of penicillin sulfoxides of Formula I
with i~ocyanates of Formula II to produce the penams of Formula III and/or the ring-expanded cephams and cephems of Formulae IV and V, respectively, is completely unprecedented.
The literature indicates that sulfoxides react with activated is.ocyanates such as acyl isocyanates to produce sulfilimines.
The literature also indicates that activated isocyanates such as acyl isocyanates react with amides to give acyl ureaq and amidines (see, for example, H. Ulrich, Chemical Reviews, 65, 369 (19~5)). It would therefore be expected that penicillin sulfoxides would give such unwanted products upon reaction with activated isocyanates such as those described herein, particularly at elevated temperatures. To our surprise, we have found that acyl isocyanates and other activated isocyanates of Formula II, above, react with penicillin sulfoxides (in which the carboxyl group is bloc~ed) to give the new 2-carbamoyloxymethylpenams of Formula III and 3-~57~3 carbamoyloxycephams of Formula IV, as well as the corr~-sponding 3-methyl-~3-cephems of Formula V.
In terms of the ring-expansion aspect of the present invention, the use of isocyanates of Formula II offer several advantages over presently known ring expansion processes, e.g..
1) Isocyanates of Formula II maintain an anhydrous situation throughout the ring expansion reaction, thus avoiding the water-induced degradation reactions which can occur in catalytic ring expansion processes.
2) Ring expansion utilizing isocyanates of Formula II are faster than catalytic ring expansion processes.
3) I~ocyanates of Formula II are twice as effective in scavenging active hydrogen compounds than the trimethyl-silyl compound~ used in some other processes. Thus, o~e molecule of water is scavenged by one isocyanate group or by two trimethylsilyl groups.
4) Isocyanates such as acetyl isocyanate, methane-sulfonyl isocyanate, sulfonyl diisocyanate, carbonyl diisocyanate and phosphorous triisocyanate give, as reaction by-products, acetamide + C02, methanesulfonamide + C02, sulfonæmide + C02, urea + C02 and phosphorous amides ~ C02, respectively. These are simpler to handle and dispose of than by-products from processes utilizing bistrimethylsilyl urea, i.e. urea +
hexamethyldisiloxane. Further, such neutral amide by-products do not react with the lactam ring.

~5~ 3 5) ~any of the isocyanates of Formula II are substantially less expensive than bistrimethylsilyl urea ancl other trimethylsilyl ureas utilized in other ring expansion processes.

6) Many of the isocyanates of Formula II are liquids at room temperature. From a practical plant point of view, liquids are easier, and generally safer and less costly to dispense and handle than solids.
Most of the silyl compounds utilized in other ring-expansion processes are solids.

7) From a practical point of view, isocyanates of Formula II may be ~elected such that their by-products are ea~ily qeparated from the desired product by dif~erent techniques. For example, acyl isocyanates give water-soluble amides as by-products. Silicon tetraisocyanate, on the other hand, gives silica as a by-product, which is completely insoluble in either organic or aqueous solvents.

The starting compounds for use in the present process are either known (many are commercially available) or may be prepared by known procedures from readily available materials.
~any of the penicillin sulfoxides of Formula I are known;
others may be prepared from the corresponding penicillin by standard techniques well known to those s~illed in the art, e.g. by use of sodium metaperiodate, hydrogen peroxide in acetic acid, m-chloroperbenzoic acid, iodobenzene dichloride in aqueous pyridine, ozone, or aqueous bromine. The penicillins themselves also are either known or may be prepared by acylating 6-aminopenicillanic acid with the appropriate side-chain acid, using standard procedures known in the art.

~ ~7~ 3 The isocyanate~ of Formula II also are known or are realdily prepared by known techniques from available starting materials. Thus, acetyl i~ocyanate and ~imilar isocyanates may be prepared by the procedure de~cxibed in Berichte, 36, 3213 (1903); the preparation of chloroacetyl i~ocyanate i~
described in J. Org. Chem., 27, 3742 (1962); the preparation of 3ilicon tetraiRocyanate is described in Inorganic Syntheses, 8, 27 (1966); the preparation of sulfonyl dii~o-cyanate iR described in W. German Pa~ents 940,351 and 1,150,093, and the preparation of methylsulfonyl isocyanate is described in J. Org. Chem., 39, 1597 (1974). General procedures for the preparation of many sulfonyl $~ocyanates are given in Chemical Reviews, 65, 369 (1965) and references cited therein.

The penams of Pormulae III and IX, the cephams of Formulae rv and X, and the cephems of Formulae V and XI
provided by the pre~ent invention ~after removal of the carboxyl-protecting group to produce the free acid) are active against various Gram-po~itive and Gram-negative organi~ms and, accordingly, are useful anti~acterial agents for the treatment of diseases caused by such organi~ms in animals, including man.
The free-amino compounds of Formulae VI, VII and VIII obtained by side-chain cleavage of the compounds of Formulae III, IV and V, respectively, generally have lower antibacterial activity than compounds III-rV or IX-XI.
Although they may sometimes ~e utilized therapeutically, their primary utility i8 as intermediates in the preparation of compounds of Formulae IX-XI by re-acylation of the free amino group.

~5~ 13 The an~ibacterial compounds provided ~y the present invention may be used alone or as the (or an) active ingredient in a conventional pharmaceutical composition, by analogy with other penicillins and cephalosporins. They may be adminîstered orally, parenterally or by suppository. For oral administration the co~positions may be in the form of tablets, capsules, powders, granules, lozenges, solutions or suspensions. They may contain conventional excipients suitable to the dosaye form, e.g. binding agents, fillers, lubricants, disintegrating agents, wetting agents, stabilizers, sweetening agents, flavors, and the like. Suppo~itories will contain conventional suppository bases. For parenteral administration, one may utilize fluid unit dosage forms such as ~te~ile solutions or suspensions, or sterile powders intended for reconstitution with a sterile vehicle prior to administration. Conventional adju~ants such as preservatives, buffering agents, suspending agents, and the like may be included in parenteral compositions.

The compositions may contain from 0.1% to 99% by weight of the antibacterial compounds of the present invention.
When the compositions are in unit dosage form, each unit will contain from about 100-750 mg of the active ingredient.
They are administered in an amount of from about 15 to about 250 mg/kg/day in divided doses, e.g. 3 to 4 times per day.

It will be appreciated by those skilled in the art that the penams ~III and IXJ, cephams (rV and X~ and cephems (V and XI~ pro~ided ~y the present invention potential}y contain an asymmetric carbon atom in their side-chain.

It is specifically intended that this invention include all possible epimers, as well as mixtures thereof.

7~3 The Minimum Inhibitory Concentrations (MICIs) of some of the compounds of thig invention were detexmined against a number of organisms, and the results are shown in Table 1.
The substituents ~R" and "X~ in Table 1 ref er to the stated substituents on the following skeletal struc~ure S~

~J~
COO~

This inventlon is illustrated by, but in no way limited to, the specific Examples.

~L~57~13 ~ -- ~ ~ ~1 ~ ~
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_ . _ _ , ~7~3 Ex~mpl~ 1 A) (2R,3S,5R,6R) 2-(U-Acetvl)car~amoYloxvmethvl-2-methYl-6-phenoxyacetamidopenam-3-carboxvlic Acid -Nitrobenz 1 Ester P Y

A solution of (lS,3S,5R,6R) 2,2-dLmethyl-6-phenoxy-acetamidopenam-3-car~oxylic acid-l-oxide p-nitrobenzyl ester (25.18 g, 50.0 mmol), acetyl isocyanate (8.50 ml, 9.53 g, 112 mmol), and dioxane (250 ml) was refluxed under ~itrogen for 5 hours, cooled and concentrated in vacuo to a yellow foam. The foam was chromato.graphed on silica gel (1.7 Kg) with methylene chloride: acetone; 9:1; v:v to give four products; the 3-methyl-~3-cephem; starting sulfoxlde, the title penam, and the cepham (in order of elution). The penam fractions were concentrated to a colorless foam in 40.2~ yield (11.80 g). Re-chromatography of a portion gave n analytical sample. m.p. 83-85; nmr 100 MHz (C~C13) ppm O O
Il il

8.40 tl,3, CNHC),- 8.20 (2, d, J = 8.5, 1/2 aromatic AB pNB), 7.56 (3, d, J = 8.5 over m, 1/2 AB, pNB and C6-NH), 7.5 (2, m) and 6.9 (3, m, O-Ph-H's), 5.7 (2, m's, C5-C6-H's), 5.32 (2, br s, pNB methylene), 4.88 (1, s, C3-H), 4.56 (2, s, OC~2C), 4.26 and 4.06 ~2, d's,J S 11.5, AB of C2-CH2O), 2.22 (3, s, C-CH3), and 1.47 (3, ~, C2-C~3); nmr 13C 4 carbonyls ca 170 ppm, carbamate carbonyl C 157.0, C~ singlet at 67.4, while C2-C~2O is t At 72.3, and C2-CH3 is q at 21~7.

Anal- Calc'd for C26H26N4l0S: C, 53.23; H, 4.47; N, 9.55.
Found: C, 53.21; H, 4.49; N, 9.39.

~57~3 B) (3S,4R,5R,6R) 3-tN-acetYl)carbamoyloxy-3-methyl-7-~henoxy~cetamidocepham-4-carboxylic acid p-nitrobenz~l ester The final chromatographic band from Step A, above, was concentrated in vacuo to give the title cepham in 12.4% yield (3.66 g): nmr (CDC13) 100 MHz ppm 9.89 (1, s, O O
CNHC), 8.23 (2, d, J - a.2 Hz, 1/2 p-NB AB), 7.56 (2, d, J =
8.2, 1/2 pNB AB) 7.24 (2, m) and 6.9 (3, m, OPh-H's), 5.55 (1, dd, J = 9.5, 4.0, C7-H), 5.32 ~3, br 9 over m, pNB-CH2 and C6-H), 4.94 (1, s, C4-H), 4.52 (2, 8, OC~2C)~ 3.56 and 3.34 (2, 2 d'~, J 3 15.5, C2-H2 AB), 2.27 (3, 9, C-C~3), and 1.60 ~3, s, C4-C~3); 13C 4 carbonyls ca 170 ppm carbamate carbonyl C 157.0, C2 (t, 29.5), C3 (s, 74.3), C4-CH3 ~q, 21.7).

Exa~le 2 (2R,3S,5R,6R) 2-(N-Acetyl)carbamoyloxvmethyl-2-methyl-6-phenoxv~cetamidopenam-3-car~oxylic Acid A suspension of 10~ palladium on charcoal (400 mg) in sthyl acetate ~40 ml) and aqueous 0.5% sodium bicarbonate was prehydrogenated and charged with t2~,3S,5R,6R) 2-(N-acetyl)carbamoyloxymethyl-2-methyl-6-phenoxyacetamidopenam-3-carboxylic acid p-nitrobenzyl ester (400 mg 0.68 mmol).
The whole was shaken at 50 psi hydrogen pressure for 30 minutes and polish filtered. The aqueous was washed with ethyl acetate ~20 ml), combined with a back extract of H20 ~ ~ ~;7~l 3 (20 ml), overlayed with ethyl acetate (25 ml) and adjusted to pH 2.9 with 35% sulfuric acid. The layers were separated and the rich organic phase was washed with water (20 ml), combined with a back extract (EtOAc, 20 ml), dried (4A
sieves)~ polish filtered and concentrated in vacuo to a colorless foam (270 mg) in 87% yield: nmr 100 MHz (CDC13-D20) ppm 7.32 (2, m, m-phenyl ~'s3 6.96 (3, m, o,p-phenyl H7s), 5.59 (2, br s, mag equiv. C5,C6-~'s), 4.79 (l, s, C3-H), 4.59 (HOD and OC~2C~, 4.08 (m, AB of C2-CH2O), 2.25 (3, s, CC~3), and 1.58 (3, s, C3-Me) with small ethyl acetate impurlty.

Ex~m~le 3 (2R,3S,5R,6R) p-Nitro~enzvl 2-(N-Chloroacetvl)-carbamo~loxymethvl-2-methvl-6-(2-phenoxyacetamido)penam-3-carboxYlate A solution of (lS,3S,5R,6R) 2,2-dimethyl-6-phenoxy-acetamidopenam-3-carboxylic acid-l-oxide p-nitrobenzyl ester (5.01 g, 10.0 mmol) and chloroacetyl isocyanate (5~0 g, 40 mmol) in dioxane (50 ml) was heated at reflux under nitrogen for 4 hours. The solution was concentrated in vacuo and crudely separated ~y filtration through silica gel (75 g) with methylene chloride:acetone (9:1, v/v).
The filtrate was concentrated and chromatographed on silica gel (140 g) with the same solvent. The second of three product bands (cephem, penam, and cepham) was concentrated in vacuo to crude product (0.53 g) a portion of which (0.23 g) -~7-~5~3 was crystallized ~rom hot methanol (5 ml, Darco) to return the title compound as a colorless ~olid (0.11 q): nmr (CDC13, O O
Il 11 100 MHz) ppm 8.46 (br s, 1, -CN~C-), 8.21 (d, 2, J = 13.2 Hz, l/2 aromatic AB p-~02benzyl), 7.4 ~overlapping m's, 5, lJ2 AB, acyl NH, and orthophenoxy), 6.95 (mls, 3, m,p-phenoxyl), 5.7 (overlapping m's, 2, C5,C6-H's), 5.30 (s, 2, benzyl-CH2), 4.81 (s, l, C3-H), 4.54 (s, 2, phenoxyacetyl CH2); 4.25 (o~er-lapping AB m's, 4, ClCH2 and C2-C~2O), and 1.45 (s, 3, CH3);
13C nmr consistent with four carbonyls ca 170 ppm and car~amate carbonyl at 157.2 ppm.

E~a~E~:_ 4 A) (2R,3S,5R,6R)2-Carbamoyloxvmethyl-2-methyl-6-(2-ethoxynaphthoylamido)penam-3-carboxylic Acid p-Nitrobenz~l Ester A solution of trichloroacetyl isocyanate (4.2 ml, 6.6 g, 35 mmol), (lS,3S,SR,6R) 2,2-dimethyl-6-(2-ethoxynaphthoyl-amido)penam-3-carboxylic acid-l-oxide p-nitrobenzyl ester (7.35 g, 12.5 mmol), and dioxane (65 ml) was refluxed under nitrogen for 3.5 hours and concentrated in vacuo to an oil.
The oil was taken into methanol (125 ml)~ the solution was adjusted to pH 7.4 with 5% sodium bicar~onate, and the mixture was held at pH 7.4 to 7.5 with 3% H2SO4 for 2 hours.
A precipitate was removed by filtration with a methanol wash (20 ml), and the filtrate was distributed between methylene ~57~L3 chloride (250 ml) and water (80 ml). The organic lay~r was washed with water ~75 ml), combined with a back-extract ~CHC12, 75 ml~, dried (4A sieve), polish filtered, and concentrated in vacuo.

The concentrate was chromatographed on silica gel (500 g) with CX2C12:acetone, 9:1, v:v to give three major products; the ~3 cephem, the title penam, and the cepham (see below). The middle fractions were concentrated to a very pale yellow foam ~1.49 g) 19.6%:

nmr 100 MHz ~5DC13) ppm 8.41 (2, d, J = 9 Hz, 1/2 arGmatic AB pNB), 8.0-7.1 ~9, aromatics +NH), 6~08 (1, dd, J ~ 4.2, 9, C6-~1), 5.74 (1, d, J - 4.2, CS-H), 5.36 and 5.21 (2, d's, J ~ 13, A3 pNB methylene), 4.73 ~ , C3-1I), 4.60 (2, br s, NH2), 4.21 ~q, J = 7) with 4.12 ~d, J ~ 11.5, total 3, OC~2C~3 and C2-CH~0-), 3.84 ~1, d, J = 11.5, C2-CHHO), and 1.40 ~t, J = 7) with 1.38 ~g, total 6, CH2CH3 and C2-CH3)-B) ~3S,4~,5R,6R)-3-Car~amovloxy-3-methyl-7-1 2-etho~y~thoylamido ) ceæham-4 -carboxylic Acid p-Nitrobenz~l Ester The last major product fractions of Step A, a~ove, were concentrated in vac~o to give the title product as a light yellow foam (2.Ç~, 0.20 g); nmr CDC13 80 M~z ppm 8.5-6.9 (7, m's, aromatics and C7-NH), 5.96 (1, dd, J = 9.3, 4.5 Hz, C7-H), 5.44 ~1, d, J = 4.5, C6-H), 4.21 ~2, s, pNB C~2), 4.87 _,~g_ (1, g, C4-H), 4.71 (2, br s, -NH2), 4.24 (2, q, J = 7.0, CH2-CH3), 3.54 (1, br d, J - 14.6, 1/2 C2AB), 3.28 (1, d, J = 1~.6, 1/2 C2 AB), and 1.48 (s, C3-CH3) with 1.44 (t, J = 7.0, total 6).

Example 5 (2R,3S,SR,6~) 2-CarbamoYloxymethyl-2-methyl-6 (2-ethoxvnaphthoYlamido)penam-3-carboxYlic Acid The p-nitrobenzyl ester of the title compound t610 mg, 1.0 mmol) was added to a prehydrogenated suspension of 10 palladium on carbon in ethyl acetate (25 ml) and aqueous potassium bicarbonate (0.4%, 20 ml). The whole was shaken at 50 psi hydrogen pressure for 60 minutes, and cen~rifuged.
The organic phase and the solids were extracted with 0.2%
KHCO3 (2 x 20 ml) and the combined aqueous phase was washed with methylene chloride (20 ml). The aqueous phase was stirred with fresh CH2C12 (25 ml) during pH adjustment to 2.0 with 35% sulfuric acid and the layers were separated.
The rich organic phase was washed with pN 2 buffer (lS ml), combined with a back extract (CH2C12, 25 ml), dried (4A sieves), polish filtered, and concentrated in vacuo to a green-tinted foam (170 mg) 36%: nmr 100 MHz (CDC13) ppm 8.1-7.1 (8, 3 m's aromatics + C6-~H, exchangeable near 7.9), 5.98 (1, dd, J = 4, --~0--5~

8 5 Hz, C6-H), 5.75 ~1, d, J = 4, C5-}I), 5.54 (2, ~r s, exchangeable, NH2), 4.62 (1, s, C3-H), 4.23 ~q, J = 7) and 4.19 ~d, J ~ 5, 3 total, OCH2C~3 and 1/2 CXHO AB), 3.86 tl, d, J = 11.5, 1/2 C~HO), and 1.57 (s) with 1.44 ~t, J = 7, total 6~ C2-C~3 and cH2-cH3).

Exam~le 6 (2R,3S,5R,6R) 2-Carbamo~loxYmethyl-2-methyl-6-(2-phenoxyacetamido)penam-3-carboxylic Acid -Nitrobenz 1 Ester P ~

A ~olution of (lS,3S,5R,6R) 2,2-dimethyL-6-phenoxy-acetamidopenam-3-carboxylic acid-l-oxide p-nitrobenzyl ester (7.52 g, 15.0 mmol) and trichloroacetyl isocyanate (5.0 ml, 7.9 g, 42 mmol) in dioxane (75 ml) was refluxed under nitrogen for 3.5 hours and conc ntrated in vacuo. The concentrate was 3tirred with methanol (100 ml) and the solution was decanted frcm a black tar with methanol rinses ~2 x 10 ml).
The æolution was diluted with water (5 ml), adjusted to plI
7.4 with 5% sodium bicarbonate, and held at pH 7.4-7.5 with 3% H2S04 for 2.5 hours. The mixture was distributed between methylene chloride (100 ml) and water (50 ml). The organic phase was washed with water (50 ml), combined with a CH2C12 bac~ extract (50 ml), dried (4A molecular sieve~, polish filterecl with CH2C12 washes (2 x 20 ml), and c:oncentrated in vacuo to a light brown oil.
-~57~3 The oil was chromatographed on silica gel ( 500 g ) with methylene chloride:acetone, (9:1 v:v) to give the title prc~uct, as the second of two major zones, concentrated in vacuo to a pale yellow ~oam (2.01 g) 25%; identical by nmr and tlc to the analytical sample prepared by a second chromatography and concentration to a colorless foam: mp 76^d; n~r (CDC13) 100 M~z ppm 8.22 (2, d, J = 9 Hz, 1/2 aromatic AB pNB), 7.52 overlapping 6.8-7.7 (8, d, J = 9 1/2 pNB, with m's phenoxy ~1's, NH), 5.75 (dd, J = 4, 9 C6-~I) with 5.63 (d, J = 4, total 2, C5-~), 5.37 and 5.22 (2, 2 d's J - 13.5, AB pNB methylene), 4.73 (1, s, C3-H), 4.55 (2, s, -OCH2C-), 4.16 and 4.00 (2, 2 d's J - 11.5, AB C2-CH2-0), and 1.41 (3, g C2-C~3).

Anal. Calc~d for C24H24N4O9S: C, 52-93; ~, 4-44; ~, 10-29;
s, 5.89 Found: C, S2.82; H, 4.51; N, 10.11;
s, 5.78 Example 7 (2R,3SL5R,6R) 2-Carbamo~loxvmethvl-2-methvl-6-phenoxvacetamidope ~ xYlic Acid The p-nitrobenzyl es~er of the title compound (1.09 g 2.0 mmol) was added to a prehydrogenated suspension of 10% palladium on charcoal (0.55 g) in ethyl acetate (50 ml) and 0.4% aqueous potassium bicarbonate (35 ml). The whole was shaken at 50 psi hydrogen pressure for 1.4 hours and ~57~3 fi.ltered, with 0.4% bicarbonate (2 x 3 ml) and water (5 ml) wa~shes. The layera were separated and the agueous phase was walshed with CHC13 (2U ml), combined with an H20 bac~ extract ~10 ml), and stirred with CH2C12 (25 ml) during p~ adjustment to 2.0 with 35% sulfuric acid. The organic phase was separated, washed with pH 2 buffer ~10 ml), dried over 4A
sieves, polish filtered a~d concentrated in vacuo to a color~
less foam (0.25 g) in 29% yield; nmr lQ0 MHz (CDC13-D20) ppm 7.3 (2, m, meta-H's), 7.0 (3, m, o,p-~15), 5.7 ~2, m's, O
C C -~'s), 4.74 (1, s, C3-~), 4.59 12, s, OC~2C), 4.04 ~1 ea, ABq, J - 11.5, C2-C~20), 1.58 (3, s, C2-C ~ ).

Ex~

~2R,3S,5R,6R) 2-~N-Acet~l)carbamoylox~methvl-2-methyl-6-~3-(2,6-dichloro~hen~1)-5-methYlisoxa2ol-4-ylamid ~ ~enam-3-carboxylic Acid P-Nitrobenzyl Ester I

A suspension of (lS,3S,5R,6R) 2,2-dimethyl-6-~3-(2,6-dichlorophenyl)-5-methylisoxazol-4-ylamido]penam-3-carboxylic acid-l-oxide p-nitrobenzyl ester (6.21 g, 10.0 mmol~ in dioxane ~50 ml) with acetyl isocyanate (2.3 ml, 30 mmol) was stirred at reflux under nitrogen for 6 hours.
The resulting clear solution was concentrated ln vacuo to a light orange foam. Chromatography of this foam on silica gel (500 g) with methylene chloride:acetone; 9:1; v:v gave 3 major fractions, the ~3 cephem, the title penam, and the ceE~ham analog. The penam was obtained by concentration as an off-white foam in 44% yield ~3.12 g): mp 85d; nmr ~CDC13) 100 MHz ppm 8.23 ~d, J - 8.5 Hz) overlapping 8.17 (s, 3 total, O o 1/2 aromatic AB pNB and -CNHC-), 7.53 (d, J = 8.5) overlapping 7.48 (g, 5 total 1/2 pNB AB and other aromatics), 6.22 (1, d, J - 9.5, C6-N~), 5.79 (1, dd, J = 4, 9.5, C6-H), 5.58 (1, d, J = 4, C5-H), 5~39 and 5.21 ~2, 2 d's, J - 13, AB pNB methylene, 4.72 ~1, s, C3-H), 4.14 ~1, d, J = 11, C2-CHHO), 3.62 (1, d, o J = 11, C2-CHHO), 2.81 ~3, s, isox-CH3), 2.31 (3, s, CCH3), and 1.39 (3, g, C2-C~3).
nal. Calc'd for C29H25N5OloSC12: C, 4g.30; H, 3.57; ~, 4.54;
Cl, 10.04.
Found: C, 49.31; H, 3.83; s, 4.30;
Cl, 10.17.

Exam~le 9 2R,35,5R,6R) 2-(N-AcetYl)carbamovloxYmethYl-2-methyl-6-~henylacetamidoPenam-3 carboxylic Acid p-Nitrobenzyl Ester A solution of (lS,3S,5R,6R) 2,2-dimethyl-6-phenyl-acetamidopenam-3-carboxylic acid -l-oxide p-nitrobenzyl ester (4.85 g, 10.0 mmol) and acetyl isocyanate (2.3 ml, 30 mmol) in dioxane ~50 ml) was refluxed under nitroge~ for 7 hours.

~i7~3 The light orange solution was concentrated in va uo to a foa~ which was chromatographed on silica gel (500 g) with met:hylene chloride:acetone; 9:1, v:v. Two major bands were eluted; the fir~t wa~ the ~3 3-methylcephem (28%, 1.29 g) and the second was the title compound obtained in 45% yield (2.56 g) as an off-white foam: mp 83-85; nmr 100 MHz (CDC13) ppm 8.24 (2, d, J - 9 Hz, 1/2 aromatic AB pNB), 7.61 (2, d, J = 9, 1/2 pNB AB), 7.28 (5, ~, phenyl), 5.54 (2, m's C6-C5-H's), 5.40 (2, br s, pNB methylene), 4.91 (1, ~, C3-H), 4.27 1, d, J - 12, 1/2 C2-C~0 AB), 4 08 (1, d, J = 12, 1/2 C2-methylene AB), 3.12 (2, s, PhC~2CN), 2.12 (3, s, acetyl), and1.41 (3, ~, C2-Ca3).

Anal. Calc'd. for C~6H26N409S: C, S4~73; H, 4.59; N, 9.82.

Found: C, 54.53; H, 4.79; N, 9.82.

~xam~le 10 (2~!35,5R,6R) 2-(N-Acetvl)carbamoYloxymethvl-2-methvl-6-(5-methyl-3-phenyl-4-isoxazolyl)-amidoPenam-3-carboxylic Acid ~-NitrobenzYl Ester A suspension of (lS,3S,5R,6R) Z,2-dimethyl-6-(5-methyl-3-phenyl-4-isoxazolyl)amidopenam-3-carboxylic acid-l-oxide p-nitrobenzyl ester (5.53 g, 10.0 mmol) wa~ treated in refluxing dioxane (50 ml) with acetyl isocyanate (2.3 ml, 30 mmol) for 6 hours. The unreacted ester (1.26 g, 2.3 mmol) was removed by filtration and the filtrate was concen-~L~L57(~3 triated in vacuo to a dar~ yellow foam which was chromato--graphed on silica gel (500 g) with methylene chloride:acetone~
~9:1; v:v). The product fraction was concentrated ln vacuo to a colorless foam (1.02 g) in 20.5% yield; nmr 100 MHz (CDC13) ppm 9,20 (2, d, J = 8.5 Hz, 1/2 pNB AB), 8.84 O O
(1, br 5, C~C) ~ 8.50 with 8.46 (7, m's, 1~2 pNB and phenyl Hls), 8.23 (1, br d, J - 9, C6-NH), 5.76 (1, dd, J - 4, g, C6-H), 5.51 (1, d, J = 4, C~ , 5,26 and 5.19 (2, ABq, J = 13, pNB-C~2), 4.64 (1, s, C3-H), 4.03 (1, d, J = 11.5, / 2 -2-)~ 3-53 (1, d, J = ll.S, 1/2 AB C2-H20), 2.76 (3, s, oxazolyl-Me)~ 2.27 (3, s, CCH3) and 1.33 (3, s, C2-CH3)-~xample 11 A) (2R,3S,5R,6R) 2-(N-Acetvl)carbamoyloxYmethvl-2-methyl-6-(2-ethoxynaphtho~lamido)penam-3-carbo~ylic Acid p-N-trobenz~l Ester A mixture of acetyl isocyanate t2.3 ml, 30 mmol), lS,3S,SR,6R~ 2,2-dimethyl-6-(2-ethoxynaphthoylamido)penam-3-car~oxylic acid-l-oxide p-nitrobenzyl ester (~.66 g, 10.0 mmol) and dioxane (50 ml) was refluxed ~or 6 hours and concentrated in vacuo. The concentrate was chromatographed on si~ica gel (500 g) with methylene chloride:acetone, 9:1, v:v, Four major fractions were obtained; the ~3 3-methyl cepham, the starting sulfoxide, the title penam, and the ~ ~5~3 cepham analog (in order of elution). The "penam~ fractions were concentrated in vacuo to a pale yellow foam in 23% yield (1.47 g): mp, 100 d; nmr (CDC13) 100 MHz ppm 8.29 ~2, d, J =

9 Hiz, 1/2 aromatic AB pNB), 8.0-7.1 (10, m's, aromatics +
NH's), 6.09 (1, dd, J - 9, 4, C6-~), 5.77 (1, d, J = 4, C5-H), 5.37 and 5.23 ~2, 2 d's, J - 13 Hz, AB pMB.methylene), 4.73 (1, s, C3-H), 4.32 (q, J = 7) over 4.29 (d, J a 11~ 3 total CH2CH3 and 1/2 C2-CHHO), 3.91 (1, J - 11, C2-C~HO), 2.14 (3, s, CCH33, and 1.42 (6, s ~ t, J = 7, C2-CH3 and CH2CH3).

C31H30N4olos C, 57.21; H, 4.65; N, 8 61;
S, 4.g3.
Founds C, 57.12; H, 4.72; N, 8.30;
S, 4.87.

B) (3S,4R,5R,6R)-3-(N-AcetYl)carbamoyloxy-3-methyl-7 (2-ethox~naphthovlamido)cephzm-4-carboxYlic Acid p-Ni~robenzYl Ester The final product fractions of Step A, above, yielded the title co~pound as a pale yellow foam in 4.1% (0.27 g) yield; nmr (CDC13) 100 MHz ppm 8.3-7.1 (11, m's aromatics O O
and CNHC), 6.90 (1, br d, J - 8.5 Hz, C7-NH), 6.14 (1, dd, J - 4.5, 8.5, C7-H), 5.35 (2, s, pNB C ~ ), 5.16 (1, d, J z 4.5, C6-H), 4.26 (2, q, J = 7, OC~2CH3), 3.60 (1, br d, J =
18, 1~2 AB C2-CH2), 3.22 (1, d, J = 18, 1/2 AB), 2.18 (3, s, o CCH3), and 1.58 (br s) with 1.49 (t, J = 7, total 6 protons, C3-C~3 and C~2CH3).

~xam~le 12 (2~,3S,5R,6R) 2-C~ thyl-2-met~
6-t3-(2,6-dichlorophen~1)-5-methyl-4-isoxazolvl]-amido~enam-3-carbox~lic Acid p-Nitroben ~ 1 Ester A mixture of (lS,3S,5R,6R) 2,2-dimethyl-6-[3-(2,6-dichlorophenyl)-5-methyl-4-isoxazolyllamidopenam-3-car~oxylic acid-l-oxide p-nitrobenzyl ester ~6.21 g, 10.0 mmol) and trichloroacetyl isocyanate (3.3 ml, 32 mmol) in dioxane (50 ml) was refluxed for 3.5 hc~rs under nitrogen. The light yellow solution was cosled, and concentsated to an oil which wa~ stirred with methanol (100 ml~. The methanol solution was decanted, with a methanol wash (2 x 10 ml), from a little residual oil, and was adjusted to pH 7.4 with 5% godium bicarbonate. The pH was held at 7.4 to 7.5 with 3% sulfuric acid for 2 hours and the reac~ion was quenched in methylene chloride (200 ml) and water tlOO ml). The rich orga~ic layer was washed with water (100 ml), combin~d with a back extract (ClI2C12, 50 ml), dried (4A sieves), polish filtered, and concentrated in vacuo to a yellow oil.
Chromatography of the oil on silica gel (500 g) with methylene chloride:acetone, (9:1; v:~) gave four zones.
Following the void volume, fractions of 25 ml were collected;
t~bes 6-16 containing the ~3 3-methylcephem, tubes 10-18 small amounts of starting sulfoxide, tubes 20-44 the title penam, and tubes 46-74 the corresponding cepham. Tubes 21-40 of the penam fraction were combined and concentrated in vacuo to a clear light cream foam; 29.7% yield (1.97 g):

7~:~3 n~r 100 MHz ~CDC13) ppm 8.13 (2, d, J = 8.5 Hz, 1/2 aromatic AB pNB), 7.53 (d, J = 8.5) with 7.47 (tight m, total 5~ 1/2 aromatic AB and dichlorophenyl H's), 6.37 ~1, d, J = 9.2, C6-NH), 5.80 ~1, dd, J - 4.0, 9.2, C6-~), 5.55 ~1, d, J = 4.0, C5-H), 5.37 and 5.20 (2, d's, J = 12.8, pNB methylene AB), 5.0 ~2, br ~, NH2), 4.68 (1, s, C3-~), 4.10 (1, d, J ~ 11.5, 1/2 AB C2-CH~O), 3.56 ~1, d, J - 11.5, 1/2 AB C2-CH2), 2.81 (3, s, isoxazolyl CH3), 1.37 (3, s, C2-CH3).

Example 13 (2R,3S,5R,_6R) 6-(4-Nitrobenzvloxycarbonvl)amino-2-carbamoyloxYmethYl-2-methylpenam-3-car~oxy Acid p-Nitrobenzvl Ester A mixture of (lS,3S,5R,6R) 6-(4-nitrobenzyloxycarbonyl)-amino-2,2-dimethylpenam-3-carboxyllc a~id-l-oxide p-nitrobenzyl ester (8.19 g, 15.0 mmol), trichloroacetyl isocyanate (5.0 ml, 7.9 g, 42 mmol) and dioxane (75 ml) was refluxed under nitrogen for 3.5 hours and concent~ated ln vacuo to a light brown oil. The oil was stirred with warm methanol ~150 ml) for 0.5 hour a~d the solution was decantPd from a small amount of dark re~idue. The methanol solution was adjusted to pH 7.4 with 5% sodium bicarbonate and held at pH 7.4-7.5 with 3% sulfuric acid during a 2.0 hour stirring period.
The mixture was ~hen distributed between methylene chloride ~250 ml) and water (100 ml). The organic layer was washed with water (100 ml), combined with a CH2C12 back-~xtract (100 ml), dried (4A molecular sieve), poli~h filtered, and concentra~ed in vacuo to a light brcwn oil.
_ __ ~L5~3 The oil was hromatographed on silica gel ~SOQ g) with methylene chloride:acetone ~9:1 v:~) to give three major bands; (in elution order) the ~3-3-methylcephem, the title penam and the corresponding cepham. The penam fraction was concentrated in vacuo to a pale yellow foam in 19.7% (1.74 g) overall yieldt nmr 100 MHz (CDC13) 8.23 (d, J = 9.5 Hz) with 8.18 ~d, J - 8.5, total 4, 1/2 (2) aromatic AB's), 7.55 (d, J = 9.5) and 7.50 (d, J = 8.S, total 4, other 1/2 (2) aromati~ AB's), 6.36 (1, d, J = 9-5~ C6-N~, 5.63 (1, d, J - 4, C5-~), Ç.48 (-1, dd, J = 4~ 9-5~ ~6-~)' 5.31 (m) and 5.24 (s, -4, pNB methy}enes~, 5.10 (-2, br s, N~2), 4.73 (1, s, C3-U), 4.25 (1, d, J = 12, 1/2 C2 methylene AB), 3.94 (1, d, J = 12, other 1/2 C2CH2O A~), and 1.44 (3, g, C~3). Recrystallization of a portion from ether-methylene chloride returned ~mall colorles~ needles: mp 80-81.

nal. Calc'd for C24H23N5llS C, 48-89~ H~ 3.93; N~ 11-88-Found: C, 48.82; H, 3.97; N, 11.86.

Example 14 (2~,3S?5R,6R) 6-Amino-2-carbamo~loxymeth~1-2-meth~lpenam-3-car~oxylic Acid A suspension of 10% palladium on charcoal (0.50 g) in ethyl acetate (25 ml) and aqueous potassium bicarbonate (0.4%, 22.5 ml, 0.10 g inorganics) waR prehydrogenated at 50 psi hydrogen for 15 minutes. The suspension was charged under nitrogen with t2R~3s~5R~6R) 6-t4-nitrobenzyloxycarbonyl)-amino-2-carbamoyloxymethyl-2-methylpenam-3-carboxylic acid ~57~3 p-nitrobenzyl ester (0~54 g, 0.9 mmol) and the whole was shaken at 50 psi hydrogen pressure for 1.2 hours, The m~ture (pH 5.0) was centrifuged and the aqueous phase was washed with methylene chloride (2 x 15 ml), combined with a water back extract (10 ml), and concentrated to about a 2 ml volume. The rich aqueous phase was diluted with deuterium oxide (4 ml) frozen on dry-ice and lyophilized to give a light yellow solid (0.25 g; theory = 0.25 g + inorganics 0.10 g) in 66% product yield; nmr 100 MHz (D20) pp~ ~.63 (1, d, J = 4.0 Hz, C6-H), 4.46 (1, s, C3-H), C5-~ under ~OD, 4.18 (1, d, J - 11.5, 1/2 AB C2-CHH-0), 4.01 (1, d, J = 11.5, C2-C~HO), and 1.53 (3, s, C2-CH3).

E
S ~
(3S,4R,6R,7R) 7-~4-Nitrobenz~loxycarbonyl)-amino-3-carbamoy~ xy-3-methYlcepham-4-carboxylic Acid p-~itrobenzYl Ester The title c~mpound was eluted as the final fractions in the chromatographic separation of ~xample 13 in a yield of 1.1~ (0.10 g). The product was equal in nmr and tlc characteristics to an analytical sample prepared in a larger run: mp 79-80; nmr 100 MHz tCDC13) ppm 8.23 (d, J = 9.0 HZ) with 8.17 (d, J = 8.5, total 4, 1/2 aromatic AB's p-N02benzyl), 7.55 (d, J a 8.5) with 7. 5a (d, J = 9.0, total 4, 1/2 aromatic AB's), 6.47 (1, d, J = 9.5, C7-NH), 5.31 (s) and 5.22 (s) over 5.5-5.2 (m's, total 8, benzyl CH2's over C6H, C7-H
and NH2), 4.89 (1, s, C4-H), 3.54 (1, br d, J = 14.5, 1~2 AB

~7~3 C2HH), 3.29 (1~ d, J = 14.5, C2HH), and 1.53 (3, s, C3-CH3).

24H23NsO11S-1/2H2O: C, 48.15; H, 4 04;
N, 11.70; S, 5.36.
Found: C, 48.24; H, 3.96;
N, 11.68; S, 5.20 Example 16 6R,7R) 3-MethYl-7-~henoxyacetamidocePh-3-~m 4-carboxylic Acid Diphenvlmethvl Ester A solution o~ (lS,3S,SR,6R) 2,2-dimethyl-6-phenoxy-ac~tamidopenam-3-carboxylic acid-l-oxide diphenylmethyl e~ter monohydrate (5.51 g, 10.0 mmol~ in dioxane (50 ml) was stirred over Linde 4A molecular sieves ~2 g) for 16 hours and filtered with a dioxane wash (2 x lS ml). To the dried solution was added p-toluenesulfonyl isocyanate (4.3 g, 22 mmol), and the mixture was heated at reflux for 7 hours under nitrogen and then concentrated in vacuo to a light orange oil. The residue was distributed ~etw~en methylene chloride (50 ml) and water-ice (50 ml) with pH
adjustment to 8.4 using dropwise addition of 50% NaO~I, and ~75~3 back washes with C~2C12 (20 ml) and pH 10 phosphate buffer (20 ml). The combined organic extracts were dried (sieves), po:Lish filtered, and concentrated ~n vacuo to a light yellow fo~m. The foam was taken into boiling isopropanol (75 ml) and after cooling yielded a glassy solid (6.23 g). A majox portion of the solid (5.95 g) was filtered through silica gel (25 g) with CH2C12:acetone, 9:1, v/v (120 ml) and the filtrate was concentrated in vacuo to a pale yellow solid (4.02 g, 78%). Crystallization of a portion (2.72 g) from isopropanol (40 ml) returned an off-white microcrystalline solid which was collected, washed with O isopropanol (25 ml) and dried in vacuo to give the title compound (1.93 g, 71%
recovery, 55~ overall). NMR indicated 82% purity, with impurities of p-toluenesulfonamide and isopropanol.

Exam~le 17 6R,7R) 3-Meth~l-?-phenox~acetamidoceph-3-em-4-carboxvlic Acid D~phenylmethyl Ester A solution of (lS,3S,SR,6R) 2,2-dimethyl-6-phenoxy-acetamidopenam-3-carboxylic acid-l-oxide diphenylmethyl ester monohydrate in dioxane was dried over Linde 4A
molecular ~ieves and an aliquot (18 ml, ~ontaining 4.1 mmol of the ester) was charged with pyridine (0.081 ml, 1.0 mmol), acetyl bromide (0.073 ml, 1.0 mmol), and acetyl isocyanate (1.1 ml, 12 mmol). The solution was heated at reflux under nitrogen for 4 hours and concentrated ln vacuo to a brown ~S7~313 glass which was filtered through silica gel ~12 g) with 9::L, v/v methylene chloride:acetone (75 ml) to remove color and impurities. The filtrate was concentrated in vacuo to a yellow foam (1.85 g, 88%). A portion of this solid (1~61 g) was crystallized from hot isopropanol (20 ml) to return the title compound as a yellow solid (1.51 g, 94% recovery, 83% overall) of 90+~ purity by n.m.r..

ExamPle 18 (2~,3S,5R,6R) 6-Amino-2-carbamoyloxymethyl-2-meth 1 enam-3-carbox lic Acid -Nitrobenz 1 Ester Y P Y P _ Y

A solution of (2R,3S,5R,6R) 2-(N-acetyl)carbamoyloxy-methyl-2-methyl-6-phenoxyacetamidopenam-3-carboxylic acid p-nitrobenzyl ester (1.17 g,2.0 mmol) in methylene chloride (10 ml) at -40 was charged with dimethylaniline (1.03 ml, 8.0 mmol) and phosphorous pentachloride 10.92 g, 4.4 mmol).
The solution was stirred at -35 to -40 for 30 minutes and cold t--35) methanol (4.1 ml, 100 mmol) was added dropwise.
The pale green solution was stirred at -~5 to -40 for 2 hours and then quenched into ice-water (10 ml). The pH was adjusted to 1.7 with conc. ammonia and the layers were separated. The aqueous was washed with CH2C12 (5 ml), combined with a water back-extract (5 ml), and stirred with CH2C12 (10 m}) during pH adjustment to 6.5 with ammonia. The organic phase was withdrawn, washed (5 ml, H2O), combined with a bac~-extract (CH2C12, 10 ml), dried (4A sieves), filtered, ~57C~:~3 concentrated to 4 ml and diluted with heptane (10 ml~. The suspension was conoentrated to 8 ml and the liquids were decanted. The solids were treated with CH2C12 ~4 ml) and heptane tlO ml) in the same fashion, and the product was washed with heptane and dried to an off-white solid (0.28 g) 34%; nmr 100 MHz CDC13-D20 ~ 8.24 (2, d, J - 8.5 IIZ, 1~2 pNB AB), 7.56 (2, d, J = 8.5, pNB AB), 5.6B (1, ~rd J = 4, C5-~, 5.32 (2, s, benzyl C~2), 4.76 (1, s, C3-II) 4.55 (~OD
overlapping C6-H d), 4.16 and 3.97 (2, ABq J = 11.5 C2-CII2-0), 1.43 (3, s, C3-C~3), wi~h 2.36 (3/4, s, ~CH3 of impurity W-acetyl analog; -25 mol %).

Example lg (6R,7R) 3-Methyl-7-phenoxvacetamidoceph-3-em-4-carbox~lic Acid DiphenYlmethyl Ester (lS,3S,5R,6R) 2,2-Dimethyl-6-phenoxyacetamidopenam-3-carboxylic acid-l-oxide diphenylmethyl ester (25.00 gms, 45.41 mmoles) was dissolved in sieve-dried, peroxide-free dioxane t250 mls) at 25C with good agitation. To this solution, in order, were added pyridine (10.99 mls, 10.78 gms, 136~22 mmoles), acetyl bromide (0.67 mls, 1.12 gms, 9.08 mmoles) and dLmethylsilyl diisocya~ate (16.14 gms, 113.51 mmoles), and the slurry was heated to reflux (ca.
100C) for 4 hours. The dioxane slurry was then cooled to 25C, filtered, and concentrated in vacuo at 50C to a heavy oil. The oil was taken up in methylene chloride (400 mls), stirred for 15 minutes at 25C, filtered, and concentrated in vacuo to dryness. The residue was dissolved n hot l-butanol (500 mls, ca. 90-95C) and allowed to cool to 25ClC. The slurry was cooled to 0-5C for 16 hours, filtered, wa~hed with cold butanol (0-5C, 100 mls), then with *

Skellysolve B (200 mls), and oven-dried at 45C to constant weight. Yield: 20.2 gms, 86.4% of snow-white crystalline title compound. The NMR spectrum was clean and consistent for ~he desired structure, as follows:

~ MHZ H' NMR, ~(CD2C12) 2.08 (3~,s,CH3~, 3.04-3.62 (2H, m, CH2, JABz18.1 Hz), 4.55 (2H, s, CH2), 4.99-5.05 (1~, d~ ~-lactam H, JA=4.7 Hz), 5.74 5.91 (lH, m, ~-lactam H, J - 4.7 Hz), 6.75-7.50 (17~I, m, aromatic C~I, and NII).

Example 2a (6R,7R) 3-Methyl- _PhenoxYacetamidocePh-3-em-4-carbox~lic Acid Diphen~lmethYl Ester (lS,3S,SR,6R) 2,2-Dimethyl-6-phenoxyacetamidopenam-3-carboxylic acid-l-oxide diphenylmethyl ester (55.06 gms, 100.00 mmoles) was dissolved in sieve-dried, peroxide-free dioxane (550 mls) at 25C with good agitation. To this solution, in order, were added pyridine ~24.21 mls, 23.73 gms, 300.00 mmoles), acetyl brom~ide (1.48 mls, 2.46 gms, 20.00 mmoles) and methylsilyl triisocyanate (89% pure, 21.30 mls, 25.-~4 gms, 133.33 mmoles). The slurry was heated to reflux (ca 100C) for 4 hours. The reaction mixture was then cooled to 25C and filtered, with the clear yellow *Trade Mar~ -66-~L57~3~3 fiLtrate ~eing concentrated in vacuo at 50C to a highly vi~scous oil~ The oil was dissolved in hot 2-propanol (-80C, 3000 mls), filtered, and allowed to cool to 25C. The slurry was cooled to 0-5C for 2 hours, filtered, and washed with 2-propanol (0-5C, 400 mls), and oven dried at 45C to constant weight. Yield: 38.6 gms, 75~ of white crystalline title compound. The 80 MHz H' NMR spectrum was clean and consistent for the desired structure.

Example 21 (2R,3S,5R,6R) 2-~N-Acetyl)carbamoYloxy~ethyl-6-amino-2-met ~ lic Acid P-Nitrobenzyl Ester A solution of (2~,3S,SR,6R) 2-(N-acetyl)carbamoyloxy-methyl-2-methyl-6-phenoxyacetamidopenam-3-car~oxylic acid p-nitrobenzyl ester (4.68 gm, 8 mmols) in dry methylene chloride (40 ml) was cooled to -60 under nitrogen. It was charged with dimethylaniline (4.06 gm, 33.5 mmol) and phosphoxus pentachloride (3.68 gm, 17.7 mmol) and stirred for 30 minutes at -64 to -56, during which time the phosphorus pentachloride dsssolved. ~ solution of dry methanol (8.10 ml) in dry methylene chloride (8.10 ml) was then slowly added at -55 to -45. The reaction mixture was stirred for 20 minutes at -60 to -55 and then poured into 16 ml of ice-water. The pH was adjusted to 1.7 with concentrated ammonia and the layers were separated. The methylene chloride layer was washed with 20 ml of pH 2.0 buffer which wa~ separated and combined with the aqueous layer. Methylene chloride 7(~3 (20 ml) was added to the com~ined aqueous layers and the mixture was adjusted to pH 6.5 with concentrated ammonia. The phases were separated, the water was washed with 20 ml of me~hylene chloride, and the combined methylene chloride layers were dried over molecular sieves. After filtration, the solution was concentrated in vacuo to about 20 ml and then added dropwise to 400 ml of stirring heptane. The heptane was decanted from the solid which precipitated and was replaced by 100 ml of fresh heptane. The suspension was thoroughly stirred, filtered, washed, air dried, and finally dried in vaUo. There was obtained 1.66 gm of the title product as a white amorphous solid. The purity was estimated from its nmr spectrum to be about 90%, the remainder being primarily the non-acetylated material.

Example 22 (~R,3S,5R,6R~ 2-(N-Acet~l)carbamoyloxymethyl-6-amino-2-methyl~enam-3-carboxvlic Acid To a prehydrogenated suspension of 10% palladium on carbon (O.B3 ym), water-washed ethyl acetate (8.3 ml) and water (4.1 ml) was added (2R,3S,5R,6R) 2-(N-acetyl)carbamoy-loxymethyl-6-amino-2-methylpenam-3-carboxylic acid p-nitro-benzyl ester (0.83 gm, 1.84 mmol). The mixture was ~haken at 50 psi hydrogen pressure-for 80 minutes and filtered through Dicalite-coated paper. The aqueous phase was separated, concentrated at reduced pressure to remove volatile solvent and gases, frozen and lyophilized. There was obtained 0.38 gm of the title compound as a white amorphou~ solid.
Its nmr spectrum was consis.ent with the desired product.

*Trade Mark ~7~3 Example 23 (2R,35,5R,6R) 2-(N-Acetyl)carbamoyloxymethyl~6-E !R) -2-Amino-2-enylacetamido]-2-methYl~ena_-3-carboxylic Acid p-Nitro-benzYl Ester A solution of (2R,3S,SR,6R) ~-(N-acetyl)carbamoyloxy-methyl-6-amino-2-methylpenam-3-carboxylic acid p-nitrobenzyl ester (0.80 gm, 1.77 mmol) in methylene chloride (10 ml) was cooled to 2 and dimethylaniline (0.214 gm, 1.77 mmol) was added. To the stirred mixture was added (-)-phenylglycyl chloride hydrochloride (0.3g2 gm, 1.83 mmol) in kwo equal portions. The first portion was added at 2 and the reaction m~xture was gradually warmed to 20 over a 90 minute period.
The reaction did not appear to begin at the lower temperatures.
The second portion of the acid chloride was added at 20 and the reaction mixture was stirred at room temperature for 4-1/2 hour~. Water ~10 ml) was added and, with thorough mlxing, the p~ was adjusted to 1.7. The layers were separated, the water layer was washed with methylene chloride, and the methylene chloride layer was washed with pH 2.0 buffer. The aqueous layers were combined, adjusted to pEI 7.0 with 10%
KOH solution, and extracted with methylene chloride (2 x 10 ml). The methylene chloride extracts were combined, dried over molecular sieves and concentrated in vacuo to about 15 ml.
This solution was added dropwise to 300 ml of stirring heptane and produced a fine white amorphous solid. This was removed by filtration and dried to give 0.61 gms of the title product.
The purity was estimated from its nmr spectrum to be about 60~.

~7~3~3 Exam~1e 24 (,2R!3S,5R,6R) 2-(N-Acetvl)carbamoyloxymethyl 6-[(R~-2-_mino-2-phenylacetamidol-2-meth~l~enam-3-carboxvlic Acid To a prehydrogenated suspension of 10% palladium on carbon (O.S9 gm), water-washed ethyl acetate (6.0 ml) and water (3.0 ml) was added (2~,3S,SR,6R) 2-(N-acetyl3carbamoy-loxymethyl-6-[(R)-2-amino-2-phenylacetamidoi-2-methylpenam-3-carboxylic acid p-nitrobenzyl est~r (0.59 gm. 1.06 mmol~.
The mixture was shaken at 50 psi hydrogen pressure for 3 hours at 25 and then filtered through Dicalite-coated paper.
The aqueous phase was separated, co~centrated at reduced pressure to remove volatile solvent and gases, frozen and lyophilized. There was obtained 0.30 gm of the title compound as an amorphous solid. The purity was estimated from its nmr spectrum to be 60-70%.

Example 25 Percentage Of Penam, CePham And Cephem Formed In The Reaction Of [lS,3S,5R,6R] 2,2-Dimethyl-6-phenoxyacetamidopenam-3-carboxylic Acid-l-oxide Di~henylmethYl Ester With Different Isocyanates Under Var~ing Conditions And With Varving Subsequent Treatment Of The Initial Product -A 5% solution of [lS,3S,5R,6R] 2,2-dimethyl-6-phenoxy-acetamidopenam-3-carboxylic acid-l-oxide diphenylmethyl ester in di'oxane was prepared. Aliquots of the above solution containing 5.51 gms (10 mmols) of the penicillin sul~oxide ester were charged with 30 mmols (300 mole %) of the indicated ~ ~S7~3 isocyanate (and, where indicated, with pyridine and/or acetyl bromide). The solutions were refluxed under nitrogen for 4 hours and then concentrated in vacuo to dryness. When indicated, portions of the resulting products were further treated with base or filtered through silica gel with methylene chloride:acetone (9:1, v:v), and concentrated to dryness.
The residues were analyzed for approximate percentages of penam, cepham and ~3-cephem by integration of the nmr methyl group signals at ca. ~1.2 for the penams, ca. ~1.5 for the cephams and ca. ~2.11 for the ~3-ceph~ms.

Mole % Mole % % % %
Pyridine C~3CBr Penam Cepham Ceph~m p-ToluenesulfonYl isoc~anate (a) 0 0 57 41 2 (b) Product of (a) treated 0 7 93 in methylene chloride with tetramethylguan-idine; latter then removed with water washes.

(c) Product of ta) 0 92 8 filtered through silica gel.
Methanesulfonyl isocyanate (d) 0 0 63 27 10 (e)ao 0 57 9 34 (f)53 0 50 0 50 (g) Product of (f) 15 0 85 filtered through silica gel-(h) Product of (d) in 10 20 70 methylene chloride washed with pH 8.5 water and held 2 hrs.

(i) Product of td) 55 o 45 treated in methylene chloride witll dimethyl formamide; latter removed with water washes.

(j~ Product of ~d) 45 30 25 filtered through silica gel.

Trichloroacetvl isocvanate (k) 0 0 26 56 18 Acetvl isocYanate (1~ 0 0 7~ 25 5 (m)50 0 70 25 5 (n)0 20 68 30 2 (o)25 25 0 10 80 MethoxycarbonYl isoc~anate (p) 0 0 37 38 0 Note: Product (o) also contained about 10% of an unidentified impurity appearing at ca. ôl.6.
Product (p) also contained about 25% of an unidentified impur~ty appearing at ca. ~1.9.

Exam~le 26 Preparation of f6R,7R] 3-Methyl-7-phenoxyacetamidoceph-3-em-4-carboxvlic Acid Diphenvlmethyl Ester From ~lS!3S~5R,6R]
2 ! 2-Dimethyl-6-PhenoxyacetamidoPenam-3-carboxYlic Acid-l-ox _ e Diphenylmethyl E~ter Utilizing Various IsocYanates And Varyinq Amounts of Pyridine And Ace ~l_Bromide as Catalysts A solution of 55 gm (100 mmol) of [lS,3S,5R,6R] 2,2-dimethyl-6-phenoxyacetamidopenam-3-carboxylic acid-l-oxide diphenylmethyl ester in dioxane (500 ml) was dried over Linde 4A sieves (50 gm). Aliquots (25 ml each; 5 mmols) were withdrawn, charged with 15 mmoles (300 mole ~) of the ~S~;~013 indicated isocyanate and the indicated mole percentage of pyridine and acetyl bromide. The solutions were refluxed under nitrogen for 6 hours and then concentrated in vacuo to dryne~s. The residues wexe filtered through silica gel (:LO gm) with methylene chloride:acetone (9:1; v:v). ~he f:iltrates were concentrated in vacuo to light yellow foams which were analyzed by liquid chromatography against authentic [6R,7R] 3-methyl-7-phenoxyacetamidoceph-3-em-4-carboxylic acid diphenylmethyl ester as a standard. Listed below are the % weight yield, % activlty and % activity yield for each reaction.

Mole ~ Mole % ~ Weight % % Activity Pyridine CH3CBr Yield Activity Yield .. ~
Methanesulonvl isocYanate

10 5 110 47.2 52 30 25 110 47.8 53 50 25 130 37.5 49 ~00 50 120 27.6 33 TrichloroacetYl isocvanate 20 10 9S 37.4 36 25 20 165 28.2 48 50 25 110 41.3 45 Silicon tetraisocyanate -120 43.2 52 120 51.0 61

Claims (2)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A process for the preparation of a compound of the formula wherein Rl is hydrogen and R2 is hydrogen, an amino-protecting group or an acyl group; or Rl and R2, taken together with the nitrogen to which they are attached, form a phthalimido group, a succinimido group or a group of the formula in which R9 and R10 are (lower)alkyl, Rll is 1,4-cyclo-hexadienyl, substituted or unsubstituted phenyl, or a substituted or unsubstituted heterocyclic group, and R12 is hydrogen, an aldehyde group or a nitroso group;

R3 is hydrogen, (lower)alkoxy, (lower)alkylthio or R13CH(OH)- in which R13 is substituted or unsubstituted (lower)alkyl, or substituted or unsubstituted aryl; and -COOR7 is -COOH, a protected carboxyl group or a derivative of a carboxyl group;
which process comprises reacting a compound of the formula in which R1, R2 and R3 are as defined above and COOR4 is a protected carboxyl group or a derivative of a carboxyl group;
at a temperature up to about 200°, in an inert organic solvent, with at least an equimolar amount of an isocyanate of the formula R5 (NCO)n wherein R5 ia an acyl group, a thioacyl group, a substituted sulfonyl, sulfinyl or sulfenyl group, or a substituted metal or non-metal atom having a valence of from 2 to 5, and n is an integer or 1 to 4; in the presence of an organic base or an inorganic base which is soluble in the organic solvent, at an alkaline pH; and, if R7 is not hydrogen, optionally converting COOR7 to a carboxyl group by a conventional method.

2. The process of Claim 1 wherein the reaction is conducted in the presence of a source of bromide ions.