Biotransformation of 6-dehydroprogesterone with Aspergillus niger and Gibberella fujikuroi

Microbial transformation of 6-dehydroprogesterone (1) with Aspergillus niger yielded three new metabolites, including 6 beta-chloro-7 alpha,11 alpha-dihydroxypregna-4-ene-3,20-dione (2), 7 alpha-chloro-6 beta,11 alpha-dihydroxypregna-4-ene-3,20-dione (3), and 6 alpha,7 alpha-epoxy-11 alpha-hydroxypregna-4-ene-3,20-dione (4), and two known metabolites; 6 alpha,7 alpha-epoxypregna-4-ene-3,20-dione (5), and 11 alpha-hydroxypregna-4,6-diene-3,20-dione (6). Compounds 2, and 3 contain chlorohydrin moiety at C-6, and C-7, respectively. The biotransformation of 1 with Gibberella fujikuroi yielded a known compound, 11 alpha,17 beta-dihydroxyandrosta-4, 6-dien-3-one (7). (C) 2016 Elsevier Inc. All rights reserved.