GB1423743A - Derivatives of cephalosporin processes for their preparation and compositions incorporating them - Google Patents

Abstract

1423743 Cephem compounds ROUSSELUCLAF 1 Jan 1973 [31 Dec 1971 7 Sept 1972] 23576/75 Divided out of 1423741 Heading C2C Cephem compounds having the general Formula (I) in racemic or optically active form, and in the form of a mixture of cis and trans isomers or one of these isomers, wherein R is phenyl optionally substituted by amino, nitro or one or more halogen atoms, or is a heterocyelic radical, Y is hydrogen, hydroxyl, amino or a group -NHCOOR<SP>11</SP> in which R<SP>11</SP> is C 1 -C 5 straight or branched alkyl, A 1 is straight or branched C 2 -C 5 alkyl, C 3 -C 7 cycloalkyl or C 3 -C 7 heterocyclyl, and R 2 is hydrogen or the residue of an ester group, provided that (a) when R is aminophenyl, Y is not amino or -NHCOOR<SP>11</SP> and R 2 is not an ester residue, and (b) when Y is amino, R 2 is not an ester residue, and salts of said compounds, which compounds are novel except when A 1 is a group of formula -CH 2 -A 2 wherein A 2 is C 1 -C 4 alkyl, are prepared by N-acylating a corresponding 7-amino-cephem compound with an appropriate acid or N-acylating derivative thereof. Subsequent interconversions of various compounds (I) include hydrolysis of a compound wherein Y is -NHCOOR<SP>11</SP> to give a corresponding α-amino-acetamido cephem compound, reduction of a nitrophenylacetamido cephem compound to give an aminophenylacetamido compound, and hydrolysis or hydrogenolysis of cephem carboxylic esters to the corresponding free acids. The compounds (I) have antibiotic activity, and may be admixed with pharmaceutical carriers or diluents to give antibacterial pharmaceutical compositions.