| 摘要 |
Compounds of the formula <IMAGE> in which R1 is lower alkyl substituted by hydroxyl or by protected hydroxyl, R2 represents carboxyl or functionally altered carboxyl, and R3 denotes amino, amino substituted by lower alkyl, substituted methylenamino, or protected amino, optical isomers of compounds of the formula I, mixtures of these optical isomers and salts of those compounds of the formula I which have a salt-forming group, possess antibiotic effects. The compounds of the formula I are prepared by processes which are known per se.
|
