Hydroxylation of steroid compounds by Gelasinospora retispora

Biotransformation of androst-4-ene-3,17-dione (1), 3β-hydroxypregnan-5-en-20-one (pregnenolone, 2), 3β-hydroxyandrost-5-en-17-one (DHEA, 3) and estradiol (4) was investigated with fungus of Gelasinospora retispora. Biotransformation of 1 gave 11α-hydroxyandrost-4-ene-3,17-dione (5) in good yield. In the case of compound 2, three compounds, DHEA (3), 3β,17β-dihydroxyandrost-5-ene (6) and 3β,15β-dihydroxyandrost-5-en-17-one (7) were obtained. Moreover, DHEA (3) was converted to 3β,7α-dihydroxyandrost-5-en-17-one (8) and 3β,11α-dihydroxyandrost-5-ene-7,17-dione (9). And it was found that biotransformation of 4 affords 6β-hydroxyestradiol (10).