Abstract: The present disclosure provides a method for preparing a 7?-alkoxyoxacephem intermediate compound, the method comprising a process (S1) including: reacting a compound represented by a following chemical formula 1 with a halogen compound in an organic solvent to form a reaction product such that unreacted halogen compound remains; and adding metal alkoxide and reducing agent to the reaction product with the unreacted halogen compound remaining, thereby to produce a compound represented by a following chemical formula 2: where R is a Cl, Br, I, halogen derivative, R1 is a carboxyl protecting group including diphenylmethyl, p-methoxybenzyl, p-nitrobenzyl or hydrogen (H), and R2 is an alkyl group having 1 to 4 carbon atoms.

Abstract: A compound of the formula: wherein X is —N?, —CH?, or the like; W is —CH2— or the like; U is —S— or the like; R1 and R2 are each independently hydrogen, halogen, optionally substituted lower alkyl, or the like; R3 is hydrogen or the like; each R4 is independently hydrogen, halogen, or the like; m is an integer from 0 to 2; Q is a single bond, or the like; G is —C(?O)—, or the like; D is a single bond, —NH—, or the like; and E is a cyclic quaternary ammonium group, or an ester, a protected compound at the amino on the ring in the 7-side chain, a pharmaceutically acceptable salt, or a solvate thereof.

Abstract: The invention relates to methods of identifying genes involved in cognitive impairment and compositions for treating cognitive impairment.

Abstract: Provided are fluorescent substrates for ?-lactamases having the general formula I: in which R is a benzyl, 2-thienylmethyl, or cyanomethyl group; R? is selected from the group consisting of H, physiologically acceptable salts or metal, ester groups, ammonium cations, —CHR2OCO(CH2)nCH3, —CHR2OCOC(CH3)3, acylthiomethyl, acyloxy-alpha-benzyl, deltabutyrolactonyl, methoxycarbonyloxymethyl, phenyl, methylsulphinylmethyl, ?-morpholinoethyl, dialkylaminoethyl, and dialkylaminocarbonyloxymethyl, in which R2 is selected from the group consisting of H and lower alkyl; A is selected from the group consisting of S, O, SO, SO2 and CH2; and Z is a donor fluorescent moiety. Also provided are methods of use of the compound of general formula I.

Abstract: A compound of the formula: (wherein, T is S, SO or O; X is halogen, CN, carbamoyl optionally substituted with lower alkyl, lower alkyl, lower alkoxy, or lower alkylthio; A is substituted lower alkylene (wherein the substituent is optionally substituted mono lower alkyl, optionally substituted lower alkylidene, or optionally substituted lower alkylene); Z+ is an optionally substituted, a cation and an N atom-containing heterocyclic group), ester, amino-protected compound wherein the amino bonds to a thiazole ring at the 7-position, or pharmaceutically acceptable salt or solvate thereof.

Abstract: There is provided a process for the preparation of a compound according to Formula (II): which includes the step of cyclizing a compound of Formula (III): wherein R1, R2, R3, R4, X and m have meanings which are given in the description.

Abstract: There is provided a process for the preparation of a compound according to Formula (II): which includes the step of cyclising a compound of Formula (III): wherein R1, R2, R3, R4, X and m have meanings which are given in the description.

Abstract: A method for the recovery of an N-substituted cephalosporanic acid compound of general formula (I), wherein R2 is selected from the group consisting of adipyl (1,4-dicarboxybutane), succinyl, glutaryl, adipyl, pimelyl, suberyl, 2-carboxyethyithio)acetyl, 3-carboxyethylthio)propionyl, higher alkyl saturated and higher alkyl unsaturated dicarboxylic acids, from a complex mixture comprising in addition to the compound of general formula (I) 6-aminopenicillanic acid (6-APA) and optionally one or more N-substituted penicillanic acid compounds, comprising the steps of: (a) acidifying the complex mixture to a pH below 6.5 and maintaining the mixture below said pH at a temperature of between 10° C. and 150° C.; and/or (b) contacting the complex mixture with a carbon dioxide source; and (c) recovering the cephalosporanic acid compound of formula (I) from the mixture obtained after steps (a) and/or (b).

Abstract: A method for the recovery of a compound formula (I) from a complex mixture, comprising the steps of: (a) acidifying the complex mixture to a pH below 6.5 and maintaining the mixture below said pH at a temperature of between 50° C. and 130° C.; and/or (b) contacting the complex mixture with a carbon dioxide source; and (c) subjecting the mixture obtained after steps (a) and/or (b) to chromatography to obtain the compound of formula (I).

Abstract: Compounds of the formula and the salts, esters and amides thereof wherein Z is S, SO, SO2 or O; each of R1, R2 and R3 is independently H or substituted or unsubstituted alkyl (1-10C), substituted or unsubstituted alkenyl, substituted or unsubstituted acyl (2-11C), substituted or unsubstituted aryl (6-14C), substituted or unsubstituted arylcarbonyl (7-15C), substituted or unsubstituted arylalkyl (7-15C), substituted or unsubstituted pyridyl wherein substituents on any alkyl, alkenyl, or acyl moiety are selected from the group consisting of halo, and RO, wherein R is H or alkyl (1-6C), and substituents on any aryl or pyridyl moiety are selected from the group consisting of halo, and RO, where R is H or alkyl (1-6C), —CN and —CF3; with the proviso that R1 is not H and R1 and R3 are not identical and with the proviso that in formula (1), the B ring may contain one double bond that is located between positions 2 and 3, and in formula (2), the B ring may contain one double bond tha

Abstract: There is provided a process for the preparation of a compound according to Formula (II): 1

Abstract: The invention provides new fluorinated cephalosporin antibiotics of Formula I wherein Ra, Rb, Rc, Rd and Re, independently, are H, F or a C1-C6 alkyl-(Z)n— group having at least one fluorine substituent; X is O or S; Y is S, O, or —CH2—; Z is O, S, —SO—, or —SO2—; m and n independently are 0 or 1; and R1 is H, C1-C6-alkyl, phenyl or benzyl, each of which may optionally have up to three substituents selected from halo, C1-C4-alkoxy, phenyl, NO2, C1-C6-alkanoyl, benzoyl, or C1-C6-alkanoyloxy; or a physiologically acceptable salt thereof; and methods of preventing or treating or treating infection, particularly mastitis in ruminants, using these antibiotics.

Abstract: The invention provides new fluorinated cephalosporin antibiotics and methods of preventing or treating infection, particularly mastitis in ruminants, using these antibiotics, and veterinary and pharmaceutical formulations comprising these antibiotics.

Abstract: A method for preparing an &agr;-oxolactam comprising, reacting a corresponding &agr;-diazolactam with an oxygen donor, in the presence of a transition metal catalyst, to yield the corresponding &agr;-oxolactam.

Abstract: Compounds based on the benzoxazine ring system that are remarkably more potent than corresponding benzoyl piperidines for enhancing synaptic responses mediated by AMPA receptors are disclosed, as are methods for the preparation thereof, and methods for their use for treatment of subjects suffering from impaired nervous or intellectual functioning due to deficiencies in the number of excitatory synapses or in the number of AMPA receptors. The invention compounds can also be used for the treatment of non-impaired subjects for enhancing performance in sensory-motor and cognitive tasks which depend on brain networks utilizing AMPA receptors and for improving memory encoding.

Abstract: A compound of formula (II) or a salt: ##STR1##

Abstract: .beta.-Lactam antibiotics of formula (I) or a salt thereof, wherein R.sup.1 is hydrogen, methoxy or formamido; R.sup.2 is an acy group; CO.sub.2 R.sup.3 is a carboxy group or a carboxylate anion, or R.sup.3 is a readily removable carboxy protecting group; R.sup.4 represents up to four substituents; X is S, SO, SO.sub.2, O or CH.sub.

Abstract: .beta.-Lactam antibiotics of formula (I) or a salt thereof, wherein R.sup.1 is hydrogen, methoxy or formamido; R.sup.2 is an acyl group; CO.sub.2 R.sup.3 is a carboxy group or a carboxylate anion, or R.sup.3 is a readily removable carboxy protecting group; R.sup.4 represents up to four substituents; X is S, SO, SO.sub.2, O or CH.sub.2 ; m is 1 or 2; and n is 0, useful in the treatment of bacterial infections.

Abstract: Novel chemotherapeutic agents having utility in treating infectious diseases such as periodontal disease, certain urinary tract infections, and infectious urinary tract stones, are obtained by combining chemically a diphosphonate compound with a therapeutic agent effective against the foregoing diseases.

Abstract: Novel chemotherapeutic agents having utility in treating infectious diseases such as periodontal disease, certain urinary tract infections, infectious urinary tract stones, and bone cancer, are obtained by combining chemically a diphosphonate compound with a therapeutic agent effective against the foregoing diseases.

Abstract: The present invention provides a process for the substitution of an acylamino .beta.-lactam compound at the carbon atom carrying the acylamino group, which process comprises reacting the .beta.-lactam compound with an halogenating agent and a nucleophilic reagent; characterized in that the acylamino group has an acidic group on the carbon atom adjacent the carbonyl group.In particular the process of this invention comprises reacting a .beta.-lactam of partial structure (I): ##STR1## where X represents an acidic group; with an halogenating agent and a nucleophilic reagent.

Abstract: The present invention provides a process for making a compound having a structure according to Formula (I) ##STR1## wherein A.sup.1, A.sup.2 and A.sup.3 are independently carbon or nitrogen and R.sup.1, R.sup.3, R.sup.4 and R.sup.6 are known quinolone substituents; and wherein one of R.sup.1, R.sup.3 or R.sup.6 may be a lactam-containing moiety;or a protected form, salt, pharmaceutically-acceptable salt, biohydrolyzable ester, or solvate thereof;the process comprising reacting one or more organosilicon compounds with a compound having a structure according to Formula (II) ##STR2## wherein A.sup.1, A.sup.2 and A.sup.3, R.sup.1, R.sup.3, R.sup.4 and R.sup.6 as described above; wherein one of R.sup.1, R.sup.3 or R.sup.6 may be a lactam-containing moiety; and X is a leaving group;or a protected form, salt, biohydrolyzable ester, or solvate thereof.

Abstract: The present invention includes novel compounds or their pharmacologically acceptable salts which exhibit antibiotic activity against a wide spectrum of organisms including organisms which are resistant to .beta.-lactam antibiotics and are useful as antibacterial agents. The invention also relates to novel intermediates useful for making the novel compounds of the present invention and to novel methods for producing the novel compounds and intermediate compounds.

Abstract: A new process is described for the production of 7-alpha-aminoacyl-cephalosporin free from halogen-containing solvents by acylating 7-amino-ceph-3-em-4-carboxylic acid or a derivative thereof in a halogen-free solvent.

Abstract: .beta.-lactam antibiotics of formula (I) or a salt thereof, wherein R.sup.1 is hydrogen, methoxy of formamido; R.sup.2 is an acyl group, in particular that of an antibacterially active cephalosporin; CO.sub.2 R.sup.3 is a carboxy group or a carboxylate anion, or R.sup.3 is a readily removable carboxy protecting group (such as a pharmaceutically acceptable in vivo hydrolysable ester group); R.sup.4 represents up to four substituents selected from alkyl, alkenyl, alkynyl, alkoxy, hydroxy, halogen, amino, alkylamino, acylamino, dialkylamino, CO.sub.2 R, CONR.sub.2, SO.sub.2 NR.sub.2 (where R is hydrogen or C.sub.1-6 alkyl), aryl and heterocyclyl, which may be the same or different and wherein any R.sup.4 alkyl substituent is optionally substituted by any other R.sup.4 substituent; X is S, SO, SO.sub.2, O or CH.sub.2 ; Y is S, SO or SO.sub.2 ; and m is 1 or 2, useful in the treatment of bacterial infections in humans and animals.

Abstract: A process for preparing a .beta.-lactam compound of the formula (I): ##STR1## which comprises cyclization of an azetidinone derivative of the formula: ##STR2## is provided in which R.sup.1 is hydrogen, alkyl which is optionally substituted, or amino which is optionally substituted; R.sup.2 is a carboxy-protecting group; and X is alkylene which is optionally intervened by --O-- or --S--, and/or which is optionally substituted; and R.sup.3 is aryl which is optionally substituted.

Abstract: A process for preparing a .beta.-lactam compound of the formula (I): ##STR1## which comprises cyclization, in the presence of a catalyst, of an azetidinone derivative of the formula: ##STR2## is provided in which R.sup.1 is hydrogen, alkyl which is optionally substituted, or amino which is optionally substituted; R.sup.2 is a carboxy-protecting group; and X is alkylene which is optionally intervened by --O-- or --S--, and/or which is optionally substituted; and R.sup.3 is aryl which is optionally substituted. The catalyst is preferably a transition metal salt (especially rhodium) or is an acid.

Abstract: The invention provides compounds of the formula ##STR1## wherein X is CH.sub.2, S or O; R.sub.1 is a 3 position substituent such as hydrogen, hydroxy, halo, trifluoromethyl, C.sub.2 F.sub.5, C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 substituted alkyl, C.sub.1 -C.sub.6 alkenyl, C.sub.1 -C.sub.6 alkynyl, CH.sub.2 O(CO)R', CH.sub.2 O(CO)NH.sub.2, CO.sub.2 R', thio(C.sub.1 -C.sub.6)alkyl, thio(C.sub.1 C.sub.6)alkenyl, oxo(C.sub.1 -C.sub.6)alkyl, phosphine oxide, quaternary ammonium group, substituted or unsubstituted thiazolothio, or oxo(C.sub.1 -C.sub.6)alkenyl;wherein R' is hydrogen, C.sub.1 -C.sub.6 alkyl, or C.sub.1 -C.sub.6 alkenyl;R.sub.2 is hydrogen or a carboxy protecting group;R.sub.3 is ##STR2## (CH.sub.2).sub.n ; wherein R.sub.6 is hydrogen Me, CH.sub.2 F, CF.sub.3, C.sub.2 H.sub.5, CH.sub.2 CH.sub.2 F, CH.sub.2 CF.sub.3, C.sub.2 F.sub.5, CH.sub.2 CO.sub.2 R', CH.sub.2 CONH.sub.2, C(Me).sub.2 CO.sub.2 R', or C(Me).sub.2 CONH.sub.2 ; and n is 0-5;R.sub.4 is ##STR3## wherein Z is O, S, NH, or CH.sub.

Abstract: The invention provides complexes of the formula: ##STR1## wherein X is chloro, hydrogen, vinyl, or --CH.sub.3,Z is O;is 0-5;Y is phenyl or 1,4-cyclohexadien-1-yl;R.sub.1 and R.sub.2 are hydrogen or hydroxy, with the proviso that R.sub.1 and R.sub.2 are not both hydrogen andR.sub.3 is --COO.sup.-, --COO(C.sub.1 -C.sub.4 alkyl), --NO.sub.2 or ##STR2## wherein R.sub.4 is C.sub.1 -C.sub.4 alkyl.

Abstract: The invention provides compounds of the formula ##STR1## wherein R* is a group of the formula ##STR2## wherein R and R.sup.0 are individually C.sub.1 -C.sub.6 alkyl groups or together form a ring consisting of the nitrogen atom to which they are attached and two to seven carbon atoms, said ring optionally substituted by one or more C.sub.1 -C.sub.6 alkyl and/or C.sub.1 -C.sub.6 substituted alkyl groups;Q and Q' are individually hydrogen, C.sub.1 -C.sub.6 alkyl, or when taken together form a divalent radical of the formula --CH.dbd.CH--CH.dbd.CH--;A and A' together form a group of the formula ##STR3## wherein R.sup.2 is hydrogen or a carboxy-protecting group; X is oxygen; R.sup.1 is hydrogen, hydroxy, halo, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 substituted alkyl, C.sub.1 -C.sub.6 alkylthio, C.sub.1 -C.sub.6 substituted alkylthio, C.sub.7 -C.sub.12 phenylalkyl, C.sub.7 -C.sub.12 substituted phenylalkyl, phenyl or substituted phenyl; a group of the formula--COR.sup.3wherein R.sup.

Abstract: There is provided a cephalosporin derivative represented by the general formula (1): ##STR1## wherein R.sup.101, R.sup.102, R.sup.103 and Y.sup.101 are as difined; the general formula (2): ##STR2## wherein R.sup.201, R.sup.202 and R.sup.203 are as defined above; the general formula (3): ##STR3## wherein R.sup.301, R.sup.302, Y.sup.301, Y.sup.302 and A.sup.301 are as defined; or pharmaceutically acceptable salt thereof. The compound is useful as an active ingredient of antimicrobial agent.

Abstract: .beta.-Lactam compounds of the formula (Ia) including pharmaceutically acceptable salts and in vivo hydrolysable esters, processes for their preparation and their use as antibiotics: ##STR1## wherein R.sup.1 is hydrogen, methoxy or formamido;R.sup.2 is an acyl group, in particular that of an antibacterially active cephalosporin;CO.sub.2 R.sup.6 is a carboxy group or a carboxylate anion;R.sup.3 is a Y-lactone ring optionally containing an endocyclic double bond, which ring is optionally substituted at any carbon atom by alkyl, dialkylamino, alkoxy, hydroxy, halogen or aryl, which in the case of more than one substituent may be the same or different, or is optionally di-substituted at two adjacent carbon atoms, which are available for substitution, to form an aromatic fused bicyclic system; and X is S, SO, SO.sub.2, O or CH.sub.2.

Abstract: Antimicrobial quinolonyl lactam esters comprising a lactam-containing moiety linked, by an ester group, to the 3-carboxy group of a quinolone moiety. These compounds are of the formula: ##STR1## wherein (1) R.sup.3, R.sup.4, and R.sup.5, together with bonds "a" and "b", form certain lactam-containing moieties similar to those known in the art to have antimicrobial activity; and(2) A.sup.2, A.sup.2, A.sup.3, R.sup.7, R.sup.8, and R.sup.9 form any of a variety of quinolone or naphthyridine structures similar to those known in the art to have antimicrobial activity.

Abstract: The present invention provides a process for protecting an amino group in a compound exposed to nucleophilic reaction conditions in which the imido group used for protection is reacted with a secondary amine to form an acyl group which protects the amino group during exposure to the nucleophilic reaction conditions, after which the acylamino group may be reacted with an acid to reform the imido group so that the compound may then undergo non-nucleophilic manipulations. Also provided is a resolution method in which diasteriometric compounds having the acylamino group as described above are reacted with acid, and as these diasteriomers react at different rates to form the imido group, the reaction may be monitored so as to isolate the desired product at the appropriate point to maximize optical purity.

Abstract: .beta.-Lactam compounds of the formula (I) including pharmaceutically acceptable salts and in vivo hydrolysable esters, processes for their preparation and their use as antibiotics: ##STR1## wherein R.sup.1 is hydrogen, methoxy or formamido;R.sup.2 is an acyl group, in particular that of an antibacterially active cephalosporin;R.sup.3 is hydrogen or a readily removable carboxy protecting group (such as a pharmaceutically acceptable in-vivo hydrolysable ester group);R.sup.4 is a .gamma.- or .delta.-lactone ring optionally containing one or (where applicable) two endocyclic double bonds, which ring is optionally substituted at any carbon atom by alkyl, dialkylamino, alkoxy, hydroxy, halogen or aryl, which in the case of more than one substituent may be the same or different, or is optionally di-substituted at two adjacent carbon atoms, which are available for substitution, to form an aromatic fused bicyclic system; x and y are independently 0 or 1; X is S, SO, SO.sub.2, O or CH.sub.2 ; and Y is O or S.

Abstract: An antibacterial 3-vic-dihydroxyaroylmethylpyridiniothiomethyl cephalosporin (I) and its salts represented by the following formula: ##STR1## (wherein, R.sup.1 is amino group or acylamino; R.sup.2 is hydrogen or methoxy; R.sup.3 is hydrogen atom or substituent; R.sup.4 is vic-dihydroxyaryl; R.sup.5 is straight or branched lower alkylene; R.sup.6 is hydrogen, a carboxy-protecting group or combined with Y a negative charge; X is --O--, --S-- or sulfinyl; and Y is a counter-ion of pyridinio or combined with R.sup.6 a negative charge),a disinfecting and treating method of bacterial infection using it, and synthetic methods thereof are provided.

Abstract: A beta-lactam compound of the formula: ##STR1## wherein R.sub.1 is a hydrogen atom, a lower alkyl group or a 1-hydroxy(lower)alkyl group wherein the hydroxyl group is optionally protected, R.sub.2 is a hydrogen atom or a protective group for the nitrogen atom and R.sub.3 is a methyl group, a halomethyl group, a hydroxymethyl group, a protected hydroxymethyl group, a formyl group, a carboxyl group, a lower alkoxycarbonyl group or an ar(lower)alkoxycarbonyl group wherein the aryl group is optionally substituted, or R.sub.2 and R.sub.3 are combined together to form an oxaalkylene group and, when taken together with one nitrogen atom and two carbon atoms adjacent thereto, they represent a six-membered cyclic aminoacetal group, which is useful as a valuable intermediate in the stereospecific production of 1-methylcarbapenem compounds.

Abstract: This invention provides a method of producing a .beta.-lactam derivative represented by the formula (I): ##STR1## said method consisting essentially of the step of reacting a .beta.-lactam derivative represented by the formula (II): ##STR2## with a phenol in a reaction system which consists essentially of said .beta.-lactam derivative of formula (II) and said phenol.

Abstract: A process for preparing compounds of the formula I: ##STR1## wherein X is sulphur, oxygen, methylene or sulphinyl (R or S configuration), R.sup.3 is hydrogen or methoxy, R.sup.4 is an optionally substituted (1-4C)alky group, Y is hydrogen or a carboxyl protecting group and Q is an optionally protected amino group or an acylamino group, which comprises reacting a compound of formula (II) ##STR2## with a compound of formula (III) ##STR3## wherein R.sup.4 is as defined above and W and Z represent hydrogen atoms or a group or groups removable to yield the compound of formula (I). The compounds of the formula I are useful intermediates in the preparation of cephalosporin antibiotics.

Abstract: A process for photochemically converting 3-exomethylene cephams (or 1-carba(1-dethia)cephams or and 1-oxa(1-dethia)cephams) from the corresponding 3-alkyl-3-cephem (or 1-carba(1-dethia)cephem or 1-oxa(1-dethia)cephem) is provided. Further provided are 3-cephams useful as intermediates to 3-cephem compounds.

Abstract: .beta.-Lactam antibiotics having an .alpha.-formamido substituent on the carbon atom adjacent to the carbonyl group of the .beta.-lactam ring and in particular bicyclic compounds having the partial structure: ##STR1## Intermediates and processes for the preparation of the compounds are further disclosed.

Abstract: An antibacterial cephalosporin hydroxamic acid derivative represented by the following formula (I), processes for its preparation, compositions containing the same as an active ingredient, and a method for killing bacteria by contacting with said compound. ##STR1## (wherein, R is acyl; R.sup.1 is hydrogen or methoxy; R.sup.2 is alkylene; R.sup.3 is hydrogen, aliphatic group or a hydroxy-protecting group; R.sup.4 is hydrogen or amino-protecting group; R.sup.5 is hydrogen, light metal atom or carboxy-protecting group; and X is oxygen, sulfur, or sulfinyl).

Abstract: The presence of a copper salt during the oximation of a .beta.-lactam containing compound having glyoxylamino substituents of the formula ##STR1## by reaction with an aminooxy compound having the formulaH.sub.2 N--O--R.sub.a,or a salt or ester thereof, results in a product wherein the ratio of syn isomer to anti isomer is increased.

Abstract: A process for the preparation of a 7-acylamino-3-hydroxy-2-cephem-4-carboxylic acid, 7-acylamino-3-hydroxy-1-dethia-1-oxa-3-cephem-4-carboxylic acid or derivative thereof of the general formula ##STR1## in which R.sup.1 is hydrogen or optionally substituted alkyl, alkenyl, alkinyl, aralkyl, aryl, heteroaryl, heteroaralkyl, aryloxyalkyl, heteroaryloxyalkyl, alkoxyalkyl, arylthioalkyl, heteroarylthioalkyl, alkylthioalkyl, alkoxy, aryloxy, alkylthio or arylthio,R.sup.2 is hydrogen, a carboxy-protective group or a pharmaceutically useful ester radical, andX is sulphur or oxygen,which comprises:(a) reacting a compound of the formula ##STR2## with (i) a compound of the formula ##STR3## in which R.sup.2 and X have the abovementioned meaning and Y represents diazo (N.sub.2) or hydrogen (H.sub.2) in an inert solvent in the presence of a Lewis acid or proton acid catalyst, or(ii) a compound of the formulaHX--CH.sub.2 --C.tbd.C--COOR.sup.

Abstract: .beta.-Lactam antibiotics having an .alpha.-formamido substituent on the carbon atom adjacent to the carbonyl group of the .beta.-lactam ring and in particular bicyclic compounds having the partial structure: ##STR1## Intermediates and processes for the preparation of the compounds are further disclosed.