CEPHALOSPORIN DERIVATIVES, THEIR PREPARATION AND COMPOSITIONS CONTAINING THEM

摘要

"CEPHALOSPORIN DERIVATIVES, THEIR PREPARATION AND COMPOSITIONS-CONTAINING THEM" Compounds of formula (I): ( I ) wherein: R1 represents a lower alkyl group selected from methyl groups and ethyl groups; R2 represents a hydrogen atom or a methyl group; and R3 represents a group selected from C1-C5 alkyl and C1-C5 alkoxy groups, and pharmaceutically acceptable acid addition salts thereof hava valuable antibiotic activity and are suitable for oral administration. They may be prepared by a variety of synthetic routes.