Microbiological hydroxylation. Part XVIII. Introduction of 16α-, 9α-, and 3α-hydroxy-groups into dioxygenated 5α-androstanes by the fungus Diaporthe celastrina

Abstract

Diaporthe celastrina, a fungus not previously reported as being active with steroids, hydroxylates a range of dioxygenated 5α-androstanes generally by attack on the α-face. The sites of hydroxylation and the efficiencies of the processes depend on the positions and oxidation levels of the androstanes' substituents. 5α-Androstane-3,7-dione is converted into 3β,16α-dihydroxy-5α-androstan-7-one (45% yield); 3β-hydroxy-5α-androstan-17-one is hydroxylated in the 9α-position (55%), and 5α-androstane-7,17-dione gives the 3α-hydroxy-derivative (52%).