MICROBIOLOGICAL PROCESS FOR PREPARING SECONDARY GLUCOSIDES FROM PRIMARY DIGITALIS GLUCOSIDES

摘要

A process for the preparation of secondary digitalis glycosides of general formula (I), (wherein R1 and R2, which may be the same or different, each represents a hydrogen atom or a hydroxy group) comprises fermenting a primary glycoside of formula (II), (wherein R1 and R2are as defined above, R3 represents a hydrogen atom or an acetyl group and R4 represents a hydrogen atom or a D-glucose unit, with the proviso that at least one of R3 and R4 is other than a hydrogen atom) with a culture of a Streptomyces griseolus strain deposited at the Hungarian National Collection of Microorganisms (Budapest, Hungary) on 6th December 1977 under No. MNG 168 or a mutant thereof or with an enzyme preparation produced therefrom and separating the product of formula (I) thus obtained from the fermentation broth.