Reduction of testosterone, androstendione and their derivatives by Aphanocladium album

A strain of Aphanocladium album reduces the C-3 carbonyl group in testosterone or androstendione to to 3 alpha-allyl alcohol. In some derivatives of these steroids the same carbonyl group is reduced to allyl alcohol with stereospecificity, depending on whether chlorine at C-4 or a 17 alpha-methyl group is present. On the other hand, the presence of C-4 methyl group, a C-19 hydroxy group, a C-17 acetyl one, or a double bond conjugated with the 4-en-3- ketone system totally inhibits the formation of allyl alcohols at C-3. At the same time, the C-17 carbonyl group in androstendione or in its derivatives is reduced to a respective 17 beta-alcohol. In the derivatives with an additional 2-exomethylene group the double bond at this group is reduced.