CEPHALOSPORIN DERIVATIVES

摘要

A compound having the formula: ( I ) wherein R1 is a straight chain, branched chain or cyclic lower alkyl group which may be substituted by a carboxyl group, and each of R2 and R3 which may be the same or different, is a hydrogen atom, a hydroxyl group, a methoxy group or an acetoxy group, and R4 is a hydroxyl group, a methoxy sroup or an acetoxy group; or a pharmaceutically acceptable salt, physiologically hydrolyzable ester or solvate thereof. The compounds of the present invention exhibit superior antibacterial activities against sensitive strains of these bacteria as compared with Ceftazidime, and also exhibit excellent antibacterial activities against Ceftazidime-resistant Pseudomonas and Acinetobactor.