7-β-Acylamino-ceph-3-ems and salts and esters therefor

Claim 1

A 7-β-acylamino-ceph-3-em compound of the formula (II): ##EQU13## or a pharmaceutically acceptable acid addition salt thereof, wherein Py is 2-pyridyl or 3-pyridyl, R 1 is COOH, a salt of COOH selected from the sodium, potassium, calcium, magnesium, aluminum, triethylamine, procaine, dibenzylamine, triethanolamine, 1-ephenamine and ethylpiperidine or a hydrolyzable ester which breaks down in the body to the free acid selected from acetoxymethyl, pivaloyloxymethyl, α-acetoxymethyl, α-acetoxybenzyl, α-pivaloyloxyethyl, phthalide, and 3,4 dimethyl phthalide R is ##EQU14## in which R 2 is hydrogen, lower alkyl, C 3-6 cycloalkyl, cyclohexenyl, cyclohexadienyl, phenyl, p-hydroxyphenyl, thienyl, pyridyl, isoxazolyl, 3-O-chlorophenyl-5-methyl-isoxazol-4-yl, sydnonyl or tetrazolyl, X is hydrogen, hydroxy, halogen, COOH or its phenyl or indanyl ester, azido, amino, ureido, guanidino, triazolyl, tetrazolyl, cyano, formyloxy, lower alkanoyloxy or lower alkoxy; and n and m are each 0, 1, 2 or 3; or ##EQU15## in which n is 1, 2, 3 or 4 and X is as defined in (i) above, or ##EQU16## in which R 4 is lower alkyl, benzyl, phenyl, C 3-6 cycloalkyl, cyclohexenyl, cyclohexadienyl, thienyl or pyridyl, R 5 and R 6 are each hydrogen, lower alkyl, phenyl, benzyl or phenylethyl, and Z is oxygen or sulphur.