Steroid derivatives. LXXIX. Microbial 15 beta-hydroxylation of 17 alpha-acetoxy-16-methylene derivatives of the pregnane series by the action of Cunninghamella blakesleeana.

Hydroxylation of 17 alpha-acetoxy-6-chloro-16-methylene-4,6-pregnadiene-3,20-dione (Chlorosuperlutin, I) by Cunninghamella blakesleeana yielded a 15 beta-hydroxyderivative II. Analogous transformation of 17 alpha-acetoxy-16-methylene-4,6-pregnadiene-3,20-dione (Superlutin, IV) included a hydroxylation in position 15 beta and probably also in 11 beta with a concomitant reduction of the 6,7-double bond.