Abstract: The present invention provides a process for preparing a cephem derivative characterized in that an allenyl .beta.-lactam compound represented by the formula (1) ##STR1## wherein R.sup.1 is amino or protected amino, R.sup.2 is a hydrogen atom or lower alkoxyl, R.sup.3 is a hydrogen atom or carboxylic acid protecting group and X is the group --SO.sub.2 R.sup.4 or --SR.sup.4, R.sup.4 being substituted or unsubstituted aryl or substituted or unsubstituted nitrogen-containing aromatic heterocyclic group is reacted with a nucleophilic agent to obtain the derivative, the cephem derivative being represented by the formula (2) ##STR2## wherein R.sup.1, R.sup.2 and R.sup.3 are as defined above, and Y is the residue of the nucleophilic agent.

Abstract: Disclosed herein are processes for preparing a compound of the formula ##STR1## in which a novel compound of the formula ##STR2## is reacted with a beta lactam of the formula ##STR3## by treatment with a base, wherein the symbols are as defined in the specification.

Abstract: The absorption of antibiotics given through oral and rectal routes of administration is significantly enhanced by use of the antibiotic in conjunction with a two-component absorption enhancing system made up of an ether of a C.sub.6 to C.sub.18 alcohol and a polyoxyethylene glycol together with a second component selected from among polyoxyethylene glycol C.sub.6 to C.sub.18 glyceride esters, C.sub.6 to C.sub.18 carboxylic acids or salts thereof, and esters of two or more C.sub.6 to C.sub.18 carboxylic acids, glycerol and a polyoxyethylene glycol. A carrier and adjuvants are usually included. These compositions can be administered in any convenient oral or rectal dosage form, including tablets, capsules, beadlets and suppositories.

Abstract: Disclosed are an advantageous method of industrial production of tert-butyl 3-oxobutylate, which is a useful intermediate for synthesis, characterized by reacting tert-butyl alcohol with diketene in the presence of 4-(tertiary amino) pyridine, and an industrially advantageous method of producing cephalosporin compounds or pharmaceutically acceptable salts thereof, using tert-butyl 3-oxobutylate as an intermediate.

Abstract: The invention relates to new stable, crystalline forms of the t-butylester of ceftazidime of formula ##STR1## and the production thereof.

Abstract: The invention relates to an antimicrobial compound of the formula: ##STR1## wherein R.sup.1 is amino or a protected amino group,R.sup.2 is lower alkyl, lower alkenyl, carboxy (lower) alkyl or protected carboxy(lower)alkyl,R.sup.3 is hydrogen, lower alkyl, hydroxy(lower)alkyl, protected hydroxy(lower)alkyl, amino(lower)alkyl, protected amino(lower)alkyl or lower alkanoyl,R.sup.4 is hydrogen, lower alkyl or lower alkylthio, andZ is N or CHor a pharmaceutically acceptable salt thereof.

Abstract: .beta.-Lactam compounds of the formula ##STR1## wherein R.sup.5 represent cyclopropyl or methyl, useful as antibiotics.

Abstract: A novel process for the preparation of syn isomers of cephalosporanic acid derivatives of the formula ##STR1## comprising reacting first in a solvent and optionally in the presence of a base, a compound of the formula ##STR2## with a compound of the formulaR.sub.4 --SO.sub.2 --Hal IIIwherein R.sub.4 is selected from the group consisting of optionally substituted alkyl, aryl and aralkyl and Hal is a halogen and reacting the resulting product in a solvent and optionally in the presence of a base with a compound of the formula ##STR3## to obtain the compound of formula I' which are known to possess good antibiotic properties.

Abstract: 3-Substituted vinyl cephalosporin derivatives represented by the following formula: ##STR1## wherein R.sup.1 represents a hydroxyl or lower alkoxyl group, X represents a nitrogen atom or a group represented by the formula --CH.dbd., R.sup.2 represents a carboxyl group or a carboxyl group protected with a protecting group, and R.sup.3 is as defined herein, and pharmaceutically acceptable salts thereof are potent antibacterial agents. Processes for their preparation, intermediates in such processes, and antibacterial compositions containing them as active ingredients are also described.

Abstract: Cephalosporin antibiotics having a 3-position substituent of the formula:--CH.sub.2 NR.sup.1 --Y--A--Z--Qare described, wherein R.sup.1 is hydrogen or certain optionally substituted alkyl groups; Y is --CO-- or --SO.sub.2 --; A is optionally substituted phenylene or heterocyclylene; Z is a linking group and Q is a catechol or related ring system. Processes for their preparation and use are described.

Abstract: There are presented anti-bacterial cephalosporins having broad antimicrobial activity of the formula ##STR1## wherein R.sub.1 is an antibiotically active quinolonyl; R.sub.2 is selected from the group consisting of hydrogen, lower alkoxy, amino, lower alkylthio and amido; R.sub.3 is selected from the group consisting of hydrogen, and acyl group, and m is 0, 1 or 2 and the readily hydrolysable esters or salts of these compounds and hydrates of the compounds of formula I or of their esters or salts.

Abstract: A cephem derivative represented by the following formula: ##STR1## wherein R.sub.1 means a fluorine-substituted lower alkyl and A.sub.1 denotes a cyclic or acyclic ammonio group, or a non-toxic salt thereof, is prepared by reacting a compound represented by the following formula: ##STR2## wherein A.sub.1 has the same meaning as defined above, with another compound represented by the following formula: ##STR3## wherein R.sub.1 has the same meaning as defined above, and if necessary, removing the protecting groups.

Abstract: This invention relates to novel cephalosporin derivatives of the formula ##STR1## wherein R.sup.1 is hydrogen, a straight, branched, or cyclic lower alkyl group having up to six carbon atoms or a radical of the formula ##STR2## in which R.sup.3 and R.sup.4 are each independently hydrogen, methyl or ethyl, or R.sup.3 and R.sup.4, taken together with the carbon atom to which they are attached, may be a cycloalkylidene ring containing from 3 to 5 carbon atoms;R.sup.2 is a radical selected from the group consisting of ##STR3## wherein R.sup.5 is hydrogen or acetyl; R.sup.6, R.sup.7 and R.sup.8 each are independently C.sub.1-5 alkyl; n is 1 or 2; and y is 1 to 5.In another aspect, this invention relates to compounds of formula I and their nontoxic pharmaeutically acceptable salts, physiologically hydrolyzable esters or solvates.Representative compounds of this invention were selected for testing and were shown to display potent antibacterial activity.

Abstract: Disclosed are an advantageous method of industrial production of tert-butyl 3-oxobutylate, which is a useful intermediate for synthesis, characterized by reacting tert-butyl alcohol with diketene in the presence of 4-(tertiary amino) pyridine, and an industrially advantageous method of producing cephalosporin compounds or pharmaceutically acceptable salts thereof, using tert-butyl 3-oxobutylate as an intermediate.

Abstract: A water-soluble antibiotic composition which comprises crystals of a cephem compound of the following formula: ##STR1## wherein R.sup.1 is a residue of an aliphatic hydrocarbon which may have suitable substituent(s), andR.sup.2 is a heteronio (lower)alkyl, or an acid addition salt thereof, and a pharmaceutically acceptable carbonic acid salt.And a salt of new cephem compound derived from the above-mentioned cephem compound.

Abstract: The present invention relates to new cephalosporins of the formula ##STR1## wherein R.sup.1 and R.sup.2 are hydrogen or carboxy, with the proviso that both cannot be the same;R.sup.3 is hydrogen or acetyl; andR.sup.4 is a radical selected from the group consisting of ##STR2## in which n is 1 or 2, R.sup.5 is hydrogen or acetyl, and R.sup.6 is hydrogen, a lower C.sub.1-3 alkyl, or a radical selected from the group consisting of ##STR3## in which n and R.sup.5 are as defined above. In another aspect, this invention relates to processes for the preparation of the compounds of Formula I, to pharmaceutical compositions containing at least one compound of Formula I, and to intermediates in their preparation.

Abstract: Cephem derivatives of the general formula ##STR1## in which the R.sub.2 O group is in the syn-position, a process for their manufacture and pharmaceutical formulations which are active against bacterial infections and contain these compounds.

Abstract: A 3-propenylcephem derivative of the following formula: ##STR1## wherein R.sub.1 represents a fluoro-substituted lower alkyl group or a cyano-substituted lower alkyl group, and A represents a cyclic or an acylic ammonio group, or a pharmaceutically acceptable salt thereof, exhibiting excellent anti-bacterial activities against both Gram-positive bacteria and Gram-negative bacteria; Process for the preparation thereof; Anti-bacterial composition; Intermediate for the 3-propenylcephem derivative; and Process for the preparation of the intermediate.

Abstract: The present invention relates to a compound having the formula: ##STR1## wherein R is a hydrogen atom, a carboxyl-protecting group or a negative charge and Q is a hydrogen atom, a halogen atom, a hydroxyl group, an acetoxy group, a carbamoyl group, an azide group, a substituted or unsubstituted quarternary ammonio group or a substituted or unsubstituted heterocyclic thio group having at least one hetero atom selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom, or a non-toxic salt or physiologically hydrolyzable non-toxic ester thereof; a process for producing it; and an antibacterial agent comprising it as an active ingredient.Further, the present invention also relates to a compound having the formula: ##STR2## wherein R.sup.3 is a hydrogen atom or an amino-protecting group, and each of R.sup.4 and R.sup.5 which may be the same or different is a hydrogen atom or a carboxyl-protecting group, or a salt thereof; and a process for producing it.

Abstract: The present invention relates to novel cephalosporin derivatives with improved pharmacokinetics, corresponding to the formula: ##STR1## in which: R.sub.1, R.sub.2 and R.sub.3 represent a hydrogen atom, or R.sub.1 and R.sub.2 represent a hydrogen atom or a methyl group and R.sub.3 represents a carboxyl group, or ##STR2## form a cyclobutyl group and R.sub.3 represents a carboxyl group; and A and B are different and occupy the meta and para positions of the benzene ring, one representing a hydroxyl group and the other being selected from the groups ##STR3## and --NH--SO.sub.2 --Alk--NH.sub.2 in which Alk denotes a C.sub.2 -C.sub.4 lower alkylene group and also to the pharmaceutically acceptable salts and esters of the said derivatives.It further relates to a process for the preparation of such cephalosporins and to pharmaceutical compositions in which they are present.

Abstract: Compounds of formulae Ia and Ib ##STR1## wherein A is hydrogen atom or an organic residue, R.sup.1 is halogen atom, or an organic group, R.sup.2 is hydrogen or halogen atom, C.sub.1 -C.sub.4 alkyl or alkoxy group, R.sup.3 is hydrogen atom, C.sub.1 -C.sub.4 alkyl or alkoxy group, benzyl or a methylene group and R.sub.4 is an organic residue are disclosed. Compounds (Ia) and (Ib) are endowed with elastase inhibitory activity. A two-step process for their preparation starting from the corresponding 4-carboxy cephem or 3-carboxy penam is also provided.

Abstract: A compound selected from the group consisting of a syn isomer of a compound of the formula ##STR1## wherein R is selected from the group consisting of hydrogen, alkyl of 1 to 6 carbon atoms, alkenyl and alkynyl of 2 to 6 carbon atoms and cycloalkyl of 3 to 6 carbon atoms, all optionally substituted with at least one member of the group consisting of optionally esterified or salified carboxy, alkoxy carbonyl, carbamoyl, dimethylcarbamoyl, amino, alkylamino, dialkylamino, halogen, alkoxy and alkylthio of 1 to 4 carbon atoms, aryl, heterocyclic aryl, arylthio and heterocyclic arylthio optionally substituted by alkyl of 1 to 4 carbon atoms, R.sub.1 is selected from the group consisting of ##STR2## and A is selected from the group consisting of hydrogen, alkali metal, alkaline earth metal, magnesium, --NH.sub.4 and an organic amine or A is selected from the group consisting of the residue of an easily cleavable ester group or --COOA is --COO-- and the wavy line indicates --CH.sub.2 --R.sub.

Abstract: Novel cephalosporin compounds represented by formula (I): ##STR1## wherein R.sup.1 represents a lower alkyl group which may optionally have a substituent; each of R.sup.2 and R.sup.3 independently represents a hydrogen atom or hydroxy group; and A represents a hydrogen atom or a residue of nucleophilic compound, and pharmacologically acceptable salts or esters thereof exhibit a potent antibacterial activity against gram positive and gram negative bacteria.

Abstract: Antibacterial compounds of the formula ##STR1## wherein R is a mononuclear carbocyclic aromatic group, a 5-membered aromatic heterocyclic group which contains as the hetero (non-carbon) ring member(s) an oxygen or sulphur atom or an imino or lower alkylimino group and, optionally, one or two nitrogen atoms, or a 6-membered aromatic heterocyclic group which contains one to three nitrogen atoms as the hetero ring member(s); R.sup.1 is hydrogen or a 3-substituent which is usable in cephalosporin chemistry; A is lower alkylene or C.sub.3-7 cycloalkylene which is optionally substituted with carboxy, carbamoyl, lower alkylcarbamoyl or di-(lower alkyl)carbamoyl; Q is lower alkylene or C.sub.3-7 cycloalkylene which is optionally substituted with carboxy, carbamoyl, lower alkylcarbamoyl or di(lower alkyl)carbamoyl, or the group --NR.sup.2 -- or --NR.sup.2 NR.sup.3 --; R.sup.2 and R.sup.3 are independently hydrogen or lower alkyl; p and m are the zero or 1, n is zero, 1 or 2; R.sup.

Abstract: What are disclosed are anti-bacterially active cephalosporin compounds of the formula ##STR1## pharmaceutical preparations containing such compounds, methods of making the compounds, methods for combatting bacterial infections therewith, and intermediates for such 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: The invention provides crystallilne (6R, 7R)-7-[[2 ( 2-Amino-4-thiazolyl)-(Z)-2-(1-diphenylmethoxycarbonyl-1-methylethoxy)imino ]acetamido]-3-(1--pyridiniummethyl)-3-cephem-4-carboxylate and a process for its production.

Abstract: Cephalosporin antibiotics having a 3-position substituent of the formula: ##STR1## are described; wherein R.sup.1 is hydrogen or certain substituted alkyl groups, Z is CH or N, R.sup.2 and R.sup.3 are hydroxy or in vivo hydrolysable esters thereof, (R.sup.12).sub.n represents various optional substituents and X=Y is an olefin, oxime, azo or related group. Processes for their preparation and use are described.

Abstract: Cephalosporin antibiotics having a 3-position substituent of the formula:--CH.sub.2 NR.sup.1 --Y--A--Z--Qare described, wherein R.sup.1 is hydrogen or certain optionally substituted alkyl groups; Y is --CO-- or --SO.sub.2 --; A is optionally substituted phenylene or heterocyclylene; Z is a linking group and Q is a catechol or related ring system. Processes for their preparation and use are described.

Abstract: A cephalosporin derivative of the formula I: ##STR1## in which X is ##STR2## represents one of C-7 acyl groups known in the cephalosporin art, R3 is hydrogen or methoxy, R4 is hydrogen, optionally substituted alkyl or allyl, and R5 is an aromatic heterocyclic ring system which is linked via carbon, and which contains a quaternized nitrogen atom.

Abstract: .beta.-Lactam antibiotics have the formula (Ia) or are pharmaceutically acceptable salts or pharmaceutically acceptable in vivo hydrolysable esters thereof: ##STR1## in which the group CO.sub.2 R.sup.1 is carboxy or a carboxylate anion. The use of the compounds and processes for their preparation are disclosed.

Abstract: Cephalosporin compounds of the formula (I): ##STR1## wherein R.sup.1 and R.sup.2 may be the same or different and are a hydrogen atom or a lower alkyl group of 1-5 carbon atoms and A is a hydrogen atom or a nucleophilic compound residue or pharmacologically acceptable salts thereof have excellent antibacterial activity against Gram positive and Gram negative microorganisms.

Abstract: Reaction of a 7-aminocephalosporanic acid with a carboxylic acid in the presence of a dehydration condensing agent and an acid or acid complex provides the corresponding amide in high yield and high purity.

Abstract: An improvement in the process of preparing ceftazidime pentahydrate from ceftazidime dihydrobromide which comprises commingling a secondary-amine-type ion-exchange resin such as Amberlite LA-2 in a water-immiscible organic solvent with an aqueous solution of the dihydrobromide, stirring the mixture while maintaining a pH at or below about 6.0 and isolating ceftazidime pentahydrate from the aqueous layer. This process provides significantly higher yields of the pentahydrate than previously could be obtained from the dihydrobromide.

Abstract: Cephalosporin compounds having a 3-position substituent of the formula (I) are described:--CH.sub.2 --Y--Q (I)wherein Y is a linking group --NR.sup.4 CO--Y'--, --NR.sup.4 SO.sub.2 --Y'--, --OCO--Y;-- or --SCO--Y'-- wherein R.sup.4 is hydrogen, various optionally substituted alkyl groups or alkenyl and Y' is a bond or various optionally substituted alkylene or alkenylene groups; and Q is a benzene ring (optionally fused to a further benzene ring so forming a naphthyl group or optionally fused to a 5 or 6 membered heterocyclic aromatic group containing 1, 2 or 3 heteroatoms selected from nitrogen, oxygen and sulphur), said benzene ring (or in the case of naphthyl either benzene ring) being substituted by groups R.sup.1 and R.sup.2 which are ortho with respect to one another, wherein R.sup.1 is hydroxy or an in vivo hydrolyzable ester thereof and R.sup.

Abstract: Cephalosporins having a 3-position substituent of the formula: ##STR1## are described, wherein R.sup.5 is hydrogen, alkenyl, alkyl or substituted alkyl, Q is a mono- or bicyclic heterocyclic ring, variously substituted, Y is variously substituted alkylene, Y' represents various linking groups, m and n are independently zero or one, and P is a benzene ring with two ortho groups, one of which is hydroxy or an in-vivo hydrolysable ester thereof and the other is hydroxy, an in vivo hydrolysable ester thereof, carboxy, sulpho, hydroxymethyl, --NHSO.sub.2 CH.sub.3 or --NHCONH.sub.2 ; or P is a particularly substituted pyridone or pyranone. The use of such compounds as antibacterial agents is described, as are processes for their preparation.

Abstract: Described herein is a cephem derivative represented by the general formula: ##STR1## wherein n stands for 1 or 2, Y stands for CH or nitrogen atom, R.sub.1 represents a lower hydrocarbon group or a carboxyl-substituted, a carbamoyl-substituted, or a cyclopropyl-substituted lower alkyl group, and R.sub.2 denotes hydroxyl group, a lower alkyl group, a hydroxy-substituted lower alkyl group, or carbamoyl group. The derivative is useful as an antibacterial agent. Also described herein are processes for the production of the derivative, antibacterial composition, intermediate of the derivative and process for the production thereof.

Abstract: Cephalosporin compounds having as a 3-substituent the group: ##STR1## wherein Y represents a bond, optionally substituted alkylene or --CH.sub.2 CH.sub.2 NHCO--, P is a benzene ring substituted by groups W and Z ortho with respect to one another wherein W is hydroxy or an in vivo hydrolyzable ester thereof, Z is hydroxy, an in vivo hydrolyzable ester thereof, carboxy, sulpho, hydroxymethyl, --NHSO.sub.2 CH.sub.3 or NHCONH.sub.2, Q is a mono- or bicyclic ring system substituted by R.sup.7 wherein R.sup.7 is hydrogen or a range of groups and ring Q is optionally further substituted; are described as antibacterial agents. Processes for their preparation and their methods of use are described.

Abstract: The present invention relates to novel cephalosporin derivatives, processes for preparing thereof, compositions for preventing and/or treating infectious diseases which comprise the novel cephalosporin derivatives as active components, and the intermediate compounds in the synthesis of cephalosporin derivatives and processes for producing thereof.The present invention is based on the selection of groups containing a condensed heterocyclic ring, particularly a triazolopyrimidine ring or a thiadiazolopyrimidine ring, as substituents at the 3-position of the cephem skeleton, and of groups containing a catechol moiety, particularly a catechol carboxymethyloxyimino moiety or a catechol carboxyimino moiety, as substituents at the 7-position of the cephem skeleton.The compounds of the present invention containing the aforementioned substituents have a strong antibacterial activity against Gram-negative bacteria and also against Gram-positive bacteria including methicillin-resistant Staphylococcus aureus.

Abstract: A compound having the formula: ##STR1## wherein R is a vinyl, phenyl or aralkyl group which may be substituted; or a pharmaceutically acceptable salt, physiologically hydrolyzable ester or solvate thereof.

Abstract: Disclosed is a novel cephem compound which is either one of a cis- or trans-isomer or a mixture of the cis-and trans-isomers, represented by the following general formula (I) and a pharmacologically acceptable salt thereof: ##STR1## wherein all of the substituents are as defined hereinbefore. Also disclosed are a process for producing the above compound and its use as an anti-bacterial agent comprising the same.

Abstract: A method for producing a compound of the formula; ##STR1## wherein R stands for a hydrogen atom, an acyl group or a protective group other than acyl groups, Q stands for a hydrogen atom or an ester residue, Y stands for the residue of a nucleophilic compound and the dotted line shows the double bond at 2- or 3- position of the cephem ring or a salt thereof, characterized by allowing a compound of the formula; ##STR2## [R, Q and the dotted line are of the same meaning as above] or a salt thereof to react with a nucleophilic compound or a salt thereof and a compound of the formula; ##STR3## wherein R.sup.1, R.sup.2, R.sup.3 independently stand for a hydrocarbon group having not more than 8 carbon atoms, or R.sup.1 and R.sup.2, R.sup.1 and R.sup.3 or R.sup.2 and R.sup.

Abstract: An antibacterial agent is provided which is a cephem compound of the formula: ##STR1## wherein R.sup.1 is an acyl group; R.sup.2 is a carboxy group which may be esterified; R.sup.3 is a hydrogen atom, a lower alkyl group or cyano group; R.sup.4 is a hydrogen atom or a lower alkyl group, or R.sup.4 together with R.sup.3 is a methylene chain having 2 or 3 carbon atoms; R.sup.5 is a hydrogen atom or a lower alkyl group; A is an optionally substituted bivalent aromatic heterocyclic group which is bonded to a ring-constituting carbon atom with the adjacent sulfur atom; Y is a binding arm, sulfur or oxygen atom, --NH--, --CONH-- or --NHCO--; Z is a binding bond or --NH--; m is an integer of 0 to 4 and n is an integer of 0 to 6, or a pharmacologically acceptable salt thereof.

Abstract: This invention provides cephalosporin compounds represented by the following general formula: ##STR1## wherein R.sup.1 and R.sup.2 are same or different hydrogen atom or a lower alkyl group of 1 to 5 carbon atoms; R.sup.3 is a lower alkyl group which may optionally be substituted with a halogen atome (or atoms), an alkenyl group, or a cycloalkylmethyl group of 3 to 6 carbon atoms; and A is hydrogen atom or residue of a nucleophilic compound and pharmacologically acceptable salts thereof. These compounds have broad-spectrum antibacterial activity against Gram-positive and -negative bacteria including Pseudomonas aeruginosa, as well as against a great variety of .beta.-lactamase-producing strains.

Abstract: The present invention relates to novel cephalosporin compounds having high antimicrobial activity, which are shown by the formula(I), and to a process for preparing them ##STR1## wherein R.sup.1 is a hydrogen atom or an amino protecting group;R.sup.2 is acetoxy; andR.sup.3 is a hydrogen atom or a carboxyl protecting group (wherein when R.sup.2 contains quaternary ammonium, r.sup.2 and R.sup.3 may form a zwitter ion).The present invention also relates to the non-toxic and pharmaceutically acceptable salts of the cephalosporin compounds of the formula (I). Also described are compositions containing the antibiotics according to the present invention.

Abstract: The crystalline dihydrochloride of a specific cephalosporin derivative is stable to heat and retains its antibacterial activity even after storage over long periods at high temperature. The crystalline dihydrochloride can be obtained by removing protective groups from the cephalosporin derivative wherein the amino group and carboxy groups are protected and then crystallizing the cephalosporin derivative from a hydrochloric acid aqueous solution. The crystalline dihydrochloride is useful for pharmaceutical preparations.

Abstract: There are disclosed a .beta.-lactam compound represented by the formula (I): ##STR1## wherein R.sub.1 and R.sub.2 are independently a hydrogen atom or a lower alkyl group; M is a hydrogen atom, a protective group or an eliminatable group which is easily hydrolyzable in a human body; R' and R" are independently a hydrogen atom or a protective group; A is a mercapto group substituted by a substituted or unsubstituted polycyclic nitrogen-containing heterocyclic ring or a group represented by the following formula (a):--OOCNR.sub.3 R.sub.4 (a)where R.sub.3 and R.sub.4 are independently a hydrogen atom or a lower alkyl group, provided that R.sub.1 and R.sub.2 are both hydrogen atoms, both R.sub.3 and R.sub.4 being hydrogen atoms are excluded,or its pharmaceutically acceptable salt, and a method for preparing the same , medicinal composition for microbism therapy containing the same and intermediates for synthesis of the same.

Abstract: Disclosed 2-(syn)-hydroxyimino-acetamide derivatives of the formula: ##STR1## wherein Y is hydrogen, hydroxyl, an acyloxy, carbamoyloxy, a quaternary ammonium or a nitrogen-containing heterocyclic ring-substituted thio group; or pharmaceutically acceptable salts or esters thereof are useful as antibacterial agents. Also disclosed are processes for producing them.

Abstract: A compound of the formula: ##STR1## wherein R.sup.1 is an amino group which may be protected, R.sup.3 is a hydrogen atom or an optionally substituted hydrocarbon residue; Z is S, S.fwdarw.O, O or CH.sub.2, R.sup.4 is a hydrogen atom, methoxy group or formamido group, R.sup.13 is a hydrogen atom, methyl group, hydroxyl group or halogen atom and A.sup..sym. is an optionally substituted imidazolium-1-yl group forming a condensed ring at the 2,3- or 3,4-position or a pharmaceutically acceptable salt or ester thereof is novel and has excellent antibacterial activity.

Abstract: The present invention relates to stable cyrstalline (6R,7R)-7-[(Z)-2-(2-aminothiazol-4-yl)-2-(1-carboxy-1-methylethoxyimino)ac etamido]-3-(5,6-dihydroxy-2-methyl-2-isoindolinium)-3-cephem-4-carboxylate sulfate or its hydrate, a process for production of the compound and (6R,7R)-7-[(Z)-2-(2-aminothiazol-4-yl)-2-(1-carboxyl-1-methylethoxyimino)a cetamido]-3-(5,6-dihydroxy-2-methyl-2-isoindolinium)methyl-3-cephem-4-carbo xylate hydrochloride or its hydrate which is a starting material useful for the production of the desired compound of the present invention.