Tylosin derivatives and their manufacturing process

摘要

New tylosin derivatives having at least one acyl group at the 3- and 4''-positions of tylosin, and the acid addition salts thereof, which inhibit the growth of various microorganisms including drug-resistant bacterial isolants and which produce high blood levels through oral administration are produced by a biochemical reaction using the microorganisms of the genus Streptomyces which are selected for their newly-found ability to acylate at least one of the 3- and 4''-positions of macrolide antibiotics; they are recovered from the reacted mixture by conventional methods for recovering macrolide antibiotics.