Bioconversion of 6-(N-methyl-N-phenyl)aminomethyl androstane steroids by Nocardioides simplex

The newly synthesized (α/β)-diastereomers of 6-(N-methyl-N-phenyl)aminomethylandrost-4-ene-3,17-dione (5) and 6-(N-methyl-N-phenyl)aminomethylandrost-4-en-17β-ol-3-one (6) were firstly investigated as substrates for the whole cells of Nocardioides simplex VKM Ac-2033D in comparison with their unsubstituted analogs, - androst-4-ene-3,17-dione (1) and androst-4-en-17β-ol-3-one (2). 1(2)-Dehydroderivatives were identified as the major bioconversion products from all the substrates tested. When using the mixtures of (α/β)-stereoisomers of 5 and 6 as the substrates, only β-stereoisomers of the corresponding 1,4-diene-steroids were formed. Along with 1(2)-dehydrogenation, N. simplex VKM Ac-2033D promoted oxidation of the hydroxyl group at C-17 position of 6: both 6(α) and 6(β) were transformed to the corresponding 17-keto derivatives. No steroid core destruction was observed during the conversion of the 6-substituted androstanes 5 and 6, while it was significant when 1 or 2 was used as the substrate. The results suggested high potentials of N. simplex VKM Ac-2033D for the generation of novel 1(2)-dehydroanalogs.