Biotransformation XLV.: Transformations of 4-ene-3-oxo steroids in Fusarium culmorum culture

The course of transformations of five 4-ene-3-oxo steroids with varying substituents at C-17 i.e.: 4-androsten-3-one, androstenedione, testosterone, progesterone and 17 alpha-hydroxyprogesterone in Fusarium culmorum culture was investigated. All the substrates were hydroxylated either at 12 beta and 15 alpha, or at 15 alpha or 6 beta positions, depending on the structure of the substrate. The main product of 4-androsten-3-one transformation was 12 beta,15 alpha-diol. A similar 12 beta,15 alpha-diol was obtained from progesterone, but the main product of transformation of this substrate was 15 alpha-hydroxyprogesterone. The products of hydroxylation at 6 beta or 15 alpha positions were isolated from 17 alpha-hydroxyprogesterone. The androstenedione and testosterone transformation mixtures contained the same products (6 beta-hydroxyandrostenedione, 6 beta-hydroxytestosterone, 15 alpha-hydroxyandrostenedione and 15 alpha-hydroxytestosterone), but the quantities of 6 beta- and 15 alpha-alcohols varied, depending on the substrate used. During transformations of these two substrates, apart from hydroxylation, ketone-alcohol interconversion at C-17 occurred. (C) 1998 Elsevier Science Ltd. All rights reserved.