| 摘要 |
Cephalosporin derivs. of formula (I) and their pharmaceutically acceptable salts or physiologically-cleavable esters are new: R1= 1-6C alkyl or opt. halo-substd. phenyl; A= N-bound, positively charged, 5-7 membered heterocyclic ring contg. up to 4 heteroatoms (N, O or S), opt. fused to 1 or 2 other rings and opt. substd.; when A is a 6-membered ring it cannot be pyridine, unsubstd. or substd. by 1 or 2 of 1-4C alkyl, Cl, Br, CONH2 or N-(1-4C alkyl)carbamoyl. Pref. A= 6-membered ring with 1-3N and opt. 1 or 2 fused rings, opt. further substits.. |
