Biotransformation of testosterone and pregnenolone catalyzed by the fungus Botrytis cinerea

Testosterone (1), a male sex hormone, and pregnenolone (2) a precursor of many steroidal hormones, were oxidized by fermentation with the fungus Botrytis cinerea. The fermentation of 1 yielded 7 beta,17 beta-dihydroxyandrostan-3-one (3) (73%) in a yield comparable to chemical transformations, Fermentation of 2 by the same fungus afforded a major metabolite 3 beta,11 alpha,16 beta-trihydroxypregn-5-en-20-one (4) (39%) along with a minor metabolite 11 alpha,16 beta-dihydroxypregn-4-ene-3,20-dione (5) (6%). The metabolites are characterized by detailed physical and spectroscopic studies.