Abstract: Processes for preparing compounds having two or three antibiotic functionalities using quinolone derivatives, &bgr;-lactams and vancomycin and the like as the starting materials and chloride linking agents; and the novel compounds prepared by these processes, are disclosed.

Abstract: A process for preparing a 3-cephem compound represented by the formula (3), the process comprising the steps of reacting a &bgr;-lactam compound represented by the formula (1) with a phosphorus halide compound in the presence of an organic base to give an imino-&bgr;-lactam compound represented by the formula (2), adding a phenol to the same reaction system to cause decomposition due to reaction with an alcohol and simultaneously to remove the protection of carboxylic acid ester, giving a 3-cephem compound represented by the formula (3) or a salt thereof where R1, R2, R3 and X are as defined above.

Abstract: A process for preparing 3-alkenylcephem compounds characterized in that 3-alkenylcephem compound of the formula (3) is prepared in a single step by simultaneously conducting reactions of a 3-chloromethylcephem compound of the formula (1) with iodization reagent, alkali metal hydroxide or carbonate, arylphosphine and an aldehyde of the formula (2)  R4—CHO  (2) wherein R1, R2, R3 and R4 are as defined in the specification.

Abstract: A process for the production of a 3-vinylcephalosporin compound of formula I wherein R1 and R2 denote hydrogen or an organic group by a Wittig reaction reacting first a compound of formula II with a compound of formula P(R4)3 or P(OR4)3 to produce a compound of formula III and secondly reacting the compound of formula III with a weak base of formula or of formula R10—COO−W+ wherein R5 is hydrogen, alkly or aryl and R6 and R7 are each an activated group of formula —COOR8, —CN, —SO2R8, —COR8 or —CON(R8)2; or R5 and R8 are each aryl and R7 is an activated group of formula —COOR8, —CN, —SO2R8, —COR8 or —CON(R8)2, W+ is an alkali metal cation and R10 is alkyl or aryl to produce a compound of formula IV and finally reacting a compound of formula IV with a compound of formula V to produce a compound of formula I.

Abstract: The invention provides compounds of formula I and IV: wherein R1-R11 and A have any of the values defined in the specification, and their pharmaceutically acceptable salts, are useful for inhibiting &bgr;-lactamase enzymes, for enhancing the activity of &bgr;-lactam antibiotics, and for treating &bgr;-lactam resistant bacterial infections in a mammal. The invention also provides pharmaceutical compositions, processes for preparing compounds of formula I and IV, and novel intermediates useful for the synthesis of compounds of formula I and IV. The A can be, for example, thio, sulfinyl, or sulfonyl.

Abstract: A halogenating agent of the formula (1) and a method of halogenating hydroxyl group wherein R1 and R2 are the same or different and are each ethyl, propyl, isopropyl, butyl, isobutyl or allyl; X is chlorine atom or bromine atom; and Y is chlorine ion, bromine ion, dichlorophosphate ion, dibromophosphate ion, chlorosulfonate ion, bromosulfonate ion, chlorooxalate ion or bromooxalate ion.

Abstract: A process for preparing a &bgr;-hydroxyester comprising reducing a &bgr;-keto ester in the presence of a salt of ammonium borohydride.

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 relates to a new process for the depletion of 7-amino-3-[(E)-1-propen-1-yl]-3-cephem-4-carboxylic acid in mixtures of 7-amino-3-[(Z)-1-propen-1-yl]-3-cephem-4-carboxylic acid and 7-amino-3-[(E)-1-propen-1-yl]-3-cephem-4-carboxylic acid, by means of the crystalline hydrochloride or a metal or amine salt of 7-amino-3-[(z/E)-1-propen-1-yl]-3-cephem-4-carboxylic acid or by adsorption chromatography.

Abstract: A process for purification of vinyl-ACA of formula from a mixture of vinyl-ACA and 7-ADCA of formula is provided. The process comprises a) producing a mixture of a salt of vinyl-ACA and a salt of 7-ADCA in a solvent in which the salt of 7-ADCA has a higher solubility than the salt of vinyl-ACA, and b) subjecting the mixture to crystallization to obtain a precipitate of the salt of vinyl-ACA. A process of purifying vinyl-ACA from a mixture of vinyl-ACA and 7-ADCA via chromatography, particularly adsorption chromatography is also provided.

Abstract: A process for preparing halogenated &bgr;-lactam compounds, characterized in that a &bgr;-lactam amino compound of the formula (1) is reacted with nitrous acid or nitrite in a slurry dispersion state in water, under acid condition in the presence of halogen molecules, thereby obtaining a halogenated &bgr;-lactam compound of the formula (4) wherein n is an integer of 0 to 2; A is the formula (2) or (3); R1 and R2 are the same or different and are hydrogen atom, halogen atom, C1˜C3 alkyl group, C2˜C4 alkenyl group, C2˜C4 alkynyl group, nucleophilic group, or CH2R3; and R3 is halogen atom or nucleophilic group  wherein A is as defined above; X1 is hydrogen atom or halogen atom; and X2 is halogen atom.

Abstract: The present invention relates to cephem-derivatives and to a process for their preparation, having proper substituents at C-2 position, i.e. heterocyclylthio or acyloxy group. They are potent protease inhibitors, in particular human leucocyte elastase (HLE) inhibitors.

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: A process for the production of a 3-vinylcephalosporin compound of formula I wherein R1 and R2 may be the same or different and denote hydrogen or an organic radical, which comprises subjecting a 3-iodomethyl-cephalosporin to a Wittig reaction in the presence of a weak base.

Abstract: The present invention provides substituted amino bicyclic-&bgr;-lactam penam derivatives and substituted amino bicyclic-&bgr;-lactam cepham derivatives and their diastereoisomers of formula I, as well as compositions, methods of making, and methods of using, which exhibit excellent cysteine protease inhibitory activity and which may be used for treatment of different diseases such as cancer (including cancer metastasis), osteoporosis, rheumatoid arthritis.

Abstract: The invention relates to a new economical and simple process, using a new intermediate compound, for the production of 3′-substituted 7-amino-3-propenyl-4-cephem-carboxylic acid derivatives of formula wherein R is hydrogen, a negative charge or a silyl protecting group, Ro is hydrogen or methoxy, R1 is hydrogen or a silyl protecting group and X is the radical of a nucleophile, and their acid addition salts.

Abstract: The invention relates to a new process for the depletion of 7-amino-3-[(E)-1-propen-1-yl]-3-cephem-4-carboxylic acid in mixtures of 7-amino-3-[(Z)-1-propen-1-yl]-3-cephem-4-carboxylic acid and 7-amino-3-[(E)-1-propen-1-yl]-3-cephem-4-carboxylic acid, by means of the crystalline hydrochloride or a metal or amine salt of 7-amino-3-[(Z/E)-1-propen-1-yl]-3-cephem-4-carboxylic acid or by adsorption chromatography.

Abstract: A phloroglucide derivative having the following formula: ##STR1## wherein Q is halogen; X is CH.sub.2 or C.dbd.O; Y is cephalosporin having a formula of ##STR2## wherein Ph is phenyl, Ac is acetoxy, or pharmaceutically acceptable salts thereof, and an antibacterial pharmaceutical composition derived thereof.

Abstract: Process for purifying 7-substituted aminodeacetoxycephalosporins through the use of filter membranes. A process for purification by ultrafiltration and/or nanofiltration with a cut-off for molecular weights over 10,000 Dalton and preferably over 2000 Dalton is described. For example cephalosporin-G of increased purity, represented by a 6-8% increase in the HPLC titre, with a reduction of 50% in absorbance, is obtained using this technique. The invention makes it possible for the purified products to be used directly in the synthesis of other antibiotic compounds without the need for intermediate isolation.

Abstract: Cephalosporin derivatives of formula II ##STR1## wherein R.sup.a denotes hydrogen or a silyl group; R.sup.b denotes a group of formula --OR.sup.e, wherein R.sup.e denotes hydrogen or alkyl; and R.sup.c and R.sup.d together denote a bond; in free form or in salt form.

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

Abstract: A process for the production of a compound of formula ##STR1## wherein R.sup.a denotes hydrogen or silyl;R.sup.b denotes a group of formula --OR.sup.e, whereinR.sup.e denotes hydrogen or alkyl; andR.sup.c and R.sup.d together denote a bond;in free form or in salt form,which process comprises the step of spitting, in the presence of ozone, the double bond in position 3 of the ring structure of a compound of formula III ##STR2## wherein R.sub.2 and R.sub.3 are the same or different and independently of each other denote hydrogen or an organic group, and X.sup.- denotes the anion of an inorganic or organic acid and optionally silylating the amine group in position 7 of the ring system.

Abstract: 3-Imino-cephalosporin derivatives of formula II ##STR1## wherein Y denotes alkyl, aryl or heterocyclyl; and R.sup.a and R.sup.d denote hydrogen or a silyl group; in free form or in salt form, and methods of preparation.

Abstract: A compound having the following general formula (I): ##STR1## where R is a hydrogen atom; a linear or branched C.sub.1 -C.sub.4 alkyl group, unsubstituted or substituted by at least a phenyl group or at least a hydrogen atom; a benzyl group substituted by at least a linear or branched C.sub.1 -C.sub.4 alkyl or alkoxy group or a nitro group; a silyl substituted by at least a linear or branched, unsubstituted or substituted C.sub.1 -C.sub.4 alkyl group; n is 0 or 1; and Y is a radical of formula ##STR2## wherein A is H, OH, Cl, CH.sub.2, CH.sub.2 X, where X is F, Cl, Br, I, OH or OR' and R' is COCH.sub.3 or a linear or branched, unsubstituted or substituted C.sub.1 -C.sub.4 alkyl group and - - - represents a single or a double bond, with the proviso that when n=0 and R is H, R' is not a methyl group.

Abstract: An industrially excellent, novel process for producing cephem compounds which are useful as medicines, particularly, antibiotics and represented by the following formula (III): ##STR1## wherein R.sup.1 means either group represented by the following formula: ##STR2## R.sup.2 denotes a carboxyl group or a carboxyl anion, and R.sup.3 stands for a lower alkyl group, a halogen atom, a lower alkyl group substituted by an aliphatic acyloxy group having 1-6 carbon atoms, or any one of the groups represented by the following formulae: ##STR3## which comprises reacting in water a 3-cephem-4-carboxylate represented by the following formula (I): ##STR4## or a salt thereof with an acid chloride represented by the formula (II), R.sup.1 COCl.

Abstract: A process for the silylation of 6-aminopenicillanic acid or 7-amino-desacetoxy-cephalosporanic acid by silylation in certain carboxylic acid esters and its use in the production of 6-alpha-aminoacyl-penicillins and 7-alpha-aminoacyl-desacetoxy-cephalosporins.

Abstract: The present invention provides a process for preparing an allenyl .beta.-lactam compound represented by the formula (II) or a process for preparing a 3-halocephem compound of the formula (III) by altering the reaction conditions with use of a .beta.-lactam halide compound represented by the formula (I) serving as the starting material ##STR1## wherein R.sub.1 is a hydrogen atom, amino or protected amino, R.sub.2 is aryl which may have a substituent, n is 0 to 2, R.sub.3 is a hydrogen atom or carboxylic acid protective group, X is a halogen atom, and Y is a halogen atom or a leaving group ##STR2## wherein R.sub.1, R.sub.2, n and R.sub.3 are as defined above ##STR3## wherein R.sub.1, R.sub.3 and X are as defined above.

Abstract: The present invention provides a process for preparing 3-norcephem compound represented by the formula (2), characterized in that a hydride reagent is acted on a halogenated .beta.-lactam compound represented by the formula (1) in the presence of a cuprous compound ##STR1## wherein R.sub.1 is a hydrogen atom, amino group or protected amino group, R.sub.2 is an aryl or substituted aryl, n is 0 to 2, R.sub.3 is a hydrogen atom or carboxylic acid protective group, X is a halogen atom, and Y is a halogen atom or a leaving group ##STR2## wherein R.sub.1 and R.sub.3 are as defined above.

Abstract: A 3-[(E)-1-propenyl]cephem compound represented by formula (I): ##STR1## wherein R represents hydrogen, a protective group for an amino group, or the group shown by formula (II): ##STR2## in which R.sup.3 is a protective group for an amino group, R.sup.4 is a protective group for a hydroxyl group, and W is --CH.dbd. or --N.dbd.; R.sup.2 represents a protective group for a carboxyl group; and X represents hydrogen or chlorine. The compound is useful as an intermediate for producing cephem antibiotics and is prepared by isomerizing the corresponding 3-[(Z)-1-propenyl]cephem compound in an inert organic solvent in the presence of an aromatic thiol. The compound of formula (I) wherein X is chlorine can be converted into a 3-[(E)-3-ammonio-1-propenyl]cephem derivative through the reaction with a tertiary amine.

Abstract: The invention provides a process for preparing an allenyl .beta.-lactam of formula (4), by reacting the hydroxyl group of a .beta.-lactam of formula (1) with a reactive derivative of sulfonic acid of formula (2) to convert the compound of formula (1) to a .beta.-lactam of formula (3), thereafter reacting the resulting .beta.-lactam with a basic anion exchange resin of the type having a tertiary organic base fixed to the resin and isolating the allenyl .beta.-lactam of formula (4) with stability and high purity in a high yield.The invention also provides a process for preparing an allenyl .beta.-lactam of formula (4), by reacting the hydroxyl group of a .beta.-lactam compound of formula (1) with a reactive derivative of sulfonic acid of formula (2) to convert the compound of the formula (1) to a .beta.-lactam compound of formula (3), thereafter reacting the resulting .beta.-lactam of formula (3) with a tertiary organic base to convert the compound (3) to the allenyl .beta.

Abstract: A process for preparing a 3-halogenated cephem derivative represented by the formula (2), characterized by causing a halogenating reagent to act on an allenyl .beta.-lactam compound represented by the formula (1) in the presence of a cuprous salt or cupric salt to obtain the 3-halogenated cephem derivative ##STR1## wherein R.sup.1 is a hydrogen atom, amino or protected amino, R.sup.2 is a hydrogen atom, halogen atom, lower alkoxyl, lower acyl, lower alkyl, lower alkyl having at least one selected from hydroxyl and protected hydroxyl as a substituent, hydroxyl or protected hydroxyl, R.sup.3 is a hydrogen atom or carboxylic acid protecting group, R.sup.4 is an aromatic compound residue which may have a substituent or nitrogen-containing aromatic heterocyclic compound residue which may have a substituent, and n is 0 to 2 ##STR2## wherein R.sup.1, R.sup.2 and R.sup.3 are as defined above, X is a halogen atom.

Abstract: Compounds of formula (I) or salts thereof: ##STR1## 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 carboxy protecting group, pharmaceutically acceptable salt-forming group or in vivo hydrolysable ester group; R.sup.4 represents hydrogen or up to four substituents; X is O, S, SO or SO.sub.2 ; Y is O, S, SO or SO.sub.2 ; n is 0 or 1; and m is 1 or 2. The compounds have antibacterial activity. Methods of synthesis of, and pharmaceutical formulations containing, compounds (I) are also described.

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: The disclosed process is for the recovery of cephalexin from a mixture containing cephalexin and 7-aminodesacetoxy cephalosporanic acid (7-ADCA), wherein a mixture of cephalexin and 7-ADCA, with a pH higher than 7, which apart from any solid cephalexin being present is homogeneous at a pH between 7 and 8.5, is subjected to a pH modification until a pH lower than 7.8 is reached, and the solid substance is recovered. The disclosed process is particularly suited for application to a reaction mixture obtained after the enzymatic acylation reaction of 7-ADCA with a phenylglycine derivative as an acylation agent. Pure cephalexin can thus be recovered in a simple manner.

Abstract: The invention relates to a new process for the depletion of 7-amino-3-?(E)-1-propen-1-yl!-3-cephem-4-carboxylic acid in mixtures of 7-amino-3-?(Z)-1-propen-1-yl!-3-cephem-4-carboxylic acid and 7-amino-3-?(E)-1-propen-1-yl!-3-cephem-4 carboxylic acid, by means of the crystalline hydrochloride or a metal or amine salt of 7-amino-3-?(Z/E)-1-propen-1-yl!-3-cephem-4-carboxylic acid or by adsorption chromatography.

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: A process is described for preparing 3-exomethylene cephalosporanic acid derivatives for use in the synthesis of cephalosporin antibiotics such as ceftibuten. The process comprises electrochemical reduction of a compound of the formula (IV) ##STR1## wherein: R.sup.3 is ##STR2## is an optional sulfoxide group; n is 2 or 3; R.sup.1 is H and R is H or NHR.sup.2, where R.sup.2 is H or a protecting group selected from C.sub.6 H.sub.5 CH.sub.2 OC(O)--, C.sub.6 H.sub.5 C(O)-- or C.sub.1 -C.sub.6 alkoxy-C(O)--; or wherein R and R.sup.1 together with the carbon atom to which they are attached comprise --C(O)--, and produces the desired 3-exomethylene compounds with low levels of the corresponding 3-methyl tautomers.

Abstract: A process for the stereospecific synthesis of keto-enol tautomeric mixture of p-nitrobenzyl (1R,6R,7R)-7-phenoxyacetamido-3-oxo-3-cepham-4-(R/S)-carboxylate-1-oxide and p-nitrobenzyl (1R,6R,7R)-7-phenoxyacetamido-3-hydroxy-3-cephem-4-carboxylate-1-oxide is described. These compounds are valuable intermediates for the synthesis of cephalosporin antibiotics e.g. cefaclor.

Abstract: The present invention provides processes for making compounds of the structure(Q--L.sup.1)--L--(L.sup.2 --B)wherein(I) Q is a quinolone moiety;(II) B is a lactam moiety; and(III) L, L.sup.1, and L.sup.2 together comprise a linking moiety;comprising the steps of:(1) coupling a compound of Formula (III) with a lactam-containing compound to form an intermediate compound; and(2) cyclizing the intermediate by reaction with an organosilicon compound to give a compound of the formula (Q--L.sup.1)--L--(L.sup.2 --B).Preferably, the process additionally comprises a step prior to the coupling step, wherein protected forms of the compound of Formula (III) and the lactam compound are formed; and deprotection steps after the cyclization step, wherein the protecting groups are removed. Preferred antimicrobial compounds made by these processes are those where the beta-lactam moiety is a penem, a carbapenem, a cephem, or a carbacephem. Also preferred are those compounds where L.sup.1, L, and L.sup.

Abstract: The present invention relates to the use of known cephem derivatives of the formula: ##STR1## wherein n is zero, one or two; R.sup.1 is hydrogen or an organic radical, R.sup.2 represents halo or an organic radical or R.sup.1 and R.sup.2 taken together with the C-2 carbon atom of the cephem nucleus constitute a carbocyclic or heterocyclyl group; R.sup.3 represents R.sup.2 as defined above or an organic radical, R.sup.4 is either R.sup.1 or an organic group, R.sup.5 is either R.sup.1 as defined above or halo or C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkylthio or C.sub.1 -C.sub.6 acylamino;R.sup.6 is R.sup.2 as defined above or an organic group,or a pharmaceutically acceptable salts thereof.

Abstract: The present invention relates to the use of 7-alkylidene derivatives of cephalosporin esters, such as sulfides, sulfoxides, and sulfones, as inhibitors of human leukocyte elastase. These materials are therefore useful as anti-inflammatory and anti-degenerative agents.

Abstract: There are disclosed new compounds of formula (I), wherein R is: a hydrogen atom: a linear or branched C1-C4 alkyl group, unsubstituted or substituted by at least a phenyl group or at least a hydrogen atom: a benzyl group substituted by at least a linear or branched C1-C4 alkyl or alkoxy group or a nitro group; a silyl substituted by at least a linear or branched, unsubstituted or substituted C1-C4 alkyl group; n is 0 or 1; and Y is a radical of formula (II), wherein A is H, OH, Cl, CH2, CH2X, where X is F, Cl, Br, I, OH or OR' and R' is COCH3 or a linear or branched, unsubstituted or substituted C1-C4 alkyl group and . . . represents a single or a double bond, with the proviso that when n=0 and R is H, R' is not a methyl group; and processes for obtaining them.

Abstract: A process for the stereospecific synthesis of keto-enol tautomeric mixture of p-nitrobenzyl(1R,6R,7R)-7-phenoxyacetamido-3-oxo-3-cepham-4-(R/S)-carboxyl ate-1-oxide and p-nitrobenzyl(1R,6R,7R)-7-phenoxyacetamido-3-hydroxy-3-cephem-4-carboxylat e-1-oxide is described. This process comprisesa) reaction of 7-phenoxyacetamido-3-exomethylene-cepham-4-carboxylic acid p-nitrobenzyl ester with ozone in a inert solvent such as acetone, or methylethyl ketone optionally in the presence of a protic solvent such as methanol, acetic acid or isopropanol at a temperature ranging from -90.degree. C. to -40.degree. C. to give the corresponding ozonide and,b) decomposition of the ozonide to keto-enol tautomeric mixture of p-nitrobenzyl(1R,6R,7R)-7-phenoxyacetamido-3-oxo-3-cepham-4-(R/S)-carboxyl ate-1-oxide and p-nitrobenzyl(1R,6R,7R)-7-phenoxyacetamido-3-hydroxy-3-cephem-4-carboxylat e-1-oxide without use of any reducing agent.

Abstract: A 7-acyl-3-substituted carbamoyloxy cephem compound represented by the following formula (1): ##STR1## wherein A means a --CH.dbd. or --N.dbd. group; R.sup.1 denotes a hydroxyl, lower alkoxyl, fluorine-substituted lower alkoxyl or protected hydroxyl group; R.sup.2 and R.sup.3 are the same or different and individually represent a lower alkyl, hydroxyl-substituted lower alkyl, a carbamoyl-substituted lower alkyl group or cyano-substituted lower alkyl group, R.sup.2 is a hydrogen atom and R.sup.3 is a lower alkoxyl or alkyl group optionally substituted by one or more halogen atoms, or the group ##STR2## means a 4-6 membered heterocyclic group, which contains one nitrogen atom, or a morpholino group, said heterocyclic group or morpholino group being optionally substituted by one or more lower alkyl, hydroxyl and/or hydroxyl-substituted lower alkyl groups; and R.sup.

Abstract: The preparation of a novel crystalline cefaclor and the conversion of such a product to cefaclor monohydrate are described. The new intermediate cefaclor is a particular crystalline form and possesses the same antibiotic properties as cefaclor monohydrate.

Abstract: The invention relates to a new economical and simple process, using a new intermediate compound, for the production of 3'-substituted 7-amino-3-propenyl-4-cephem-carboxylic acid derivatives of formula ##STR1## wherein R is hydrogen, a negative charge or a silyl protecting group, R.sub.o is hydrogen or methoxy, R.sub.1 is hydrogen or a silyl protecting group and X is the radical of a nucleophile, and their acid addition salts.

Abstract: A bioavailable crystalline form of cefuroxime axetil, obtained by treating known crystalline or amorphous cefuroxime axetil with water or with a water-miscible organic solvent or with a mixture thereof at a temperature of between +20.degree. C. and +100.degree. C., followed by cooling and separating the crystalline product by known methods.

Abstract: Process for selectively reducing cephalosporin sulfoxides of 3-hydroxy cephem and 3-methylene cepham compounds by treatment with a chlorinating agent in the presence of a solvent and a base, which are both inert to the chlorinating agent.

Abstract: A process is described for preparing 3-exomethylene cephalosporanic acid derivatives for use in the synthesis of cephalosporin antibiotics such as ceftibuten. The process comprises electrochemical reduction of a compound of the formula (IV) ##STR1## wherein: R.sup.3 is CH.sub.3 C(O)--; ##STR2## is an optional sulfoxide group; n is 2 or 3; R.sup.1 is H and R is H or NHR.sup.2, where R.sup.2 is H or a protecting group selected from C.sub.6 H.sub.5 CH.sub.2 OC(O)--, C.sub.6 H.sub.5 C(O)-- or C.sub.1 -C.sub.6 alkoxy-C(O)--; or wherein R and R.sup.1 together with the carbon atom to which they are attached comprise --C(O)--, and produces the desired 3-exomethylene compounds with low levels of the corresponding 3-methyl tautomers.

Abstract: An object of the invention is to provide a process for preparing a 3-substituted cephem compound from an allenyl-.beta.-lactam compound which can be easily produced from an inexpensive penicillin compound by a simple reaction procedure.The process of the invention comprises reacting an allenyl-.beta.-lactam compound with an organohalogen compound in the presence of a metal having a standard oxidation-reduction potential of -0.3 (V/SCE) or less in an amount at least equimolar with the allenyl-.beta.-lactam compound and 0.0001 to 0.5 mole, per mole of the allenyl-.beta.-lactam compound, of a metal compound having a higher standard oxidation-reduction potential than said metal.