23-Demycinosyldesmycosin derivatives

摘要

Novel 23-demycinosyldesmycosin derivatives are disclosed of the formula <IMAGE> [1] wherein A is oxygen or sulfur, R1 is optionally substituted phenyl or <IMAGE> group, in which R3 is optionally substituted phenyl and R4 and R5 are the same or different and are hydrogen, lower alkyl or optionally substituted phenyl, and R2 is hydrogen or hydroxyl. The compounds or non-toxic salts thereof are useful as antibiotics.