5α-Androstane-3, 16-dione has been prepared by hydroboration and oxidation of 3β-hydroxy-5α-androst-16-ene. Reduction with sodium borohydride gave the 3β, 16β-diol. The fungus Cephalosporium aphidicola has been shown to hydroxylate 5α-androstane-3, 16-dione predominantly at the C-6β position with minor hydroxylation occurring at the C-7α and C-14α positions. In contrast hydroxylation of the 3β, 16β-diol took place at C-11α. The 3β-hydroxy-16α, 17α-epoxide was hydroxylated at the C-6β position.