Microbial hydroxylation of acetylaminosteroids

An investigation of the microbial biotransformation of a range of 3 beta-, 17 beta-, and 20-acetylamino C18 to C21 steroids by microorganisms known to hydroxylate conventional steroids has been undertaken, using Aspergillus ochraceus, Bacillus megaterium, Curvularia lunata, and Rhizoputus arrhizus. A. ochraceus and B. megaterium gave products of 11 alpha- and 15 beta-hydroxylation, respectively. In the case of C. lunata, the products were predominantly those of this organism's normal C-11 beta- and C-14 alpha-hydroxylating pathways, but in one instance, 3 beta-acetylamino-7 alpha-hydroxy-5 alpha-androstan-17-one, appeared to results from direction of the site of hydroxylation by the substitution pattern of the substrate. The products from R. arrhizus generally corresponded to those previously obtained from normal steroids of similar skeleton, with 6 beta- 11 alpha-hydroxylation predominating, but again the sites of hydroxylation and the range of hydroxylated products were found to depend on the substitution pattern of the substrate.