Microbiological hydroxylation. Part XIV. Hydroxylation in the terminal rings of dioxygenated 5α-androstanes with the fungi Wojnowicia graminis and Ophiobolus herpotrichus

Abstract

Dioxo-5α-androstanes having one keto-group in a terminal ring (at position 3 or 2, or at position 17) and the second at a middle ring position (7 or 11) are hydroxylated in the other terminal ring (at 17 or 16, or at 3 or 2) by the fungi Wojnowicia graminis and Ophiobolus herpotrichus. Efficient transformations include the 2α-hydroxylation of 5α-androstane-7,17-dione (with W. graminis), the 16-substitution of the 3,11-dione (with O. herpotrichus), and the 17β-hydroxylation of 3,7-dioxygenated substrates (with both fungi).