Stereoselective Hydrogen Elimination at C-2 in the Transformation of 5β-Pregnane-3, 11, 20-trione by Septomyxa affinis

Abstract

The stereochemistry of hydrogen loss at C-2 in the microbial transformation of 5β-pregnane-3, 11, 20-trione is described. Epimeric substrates stereospecifically labeled with deuterium at C-2 were incubated aerobically with Septomyxa affinis, and the biotransformation products, 5β-androst-1-ene-3, 11, 17-trione and 5β-androstane-3, 11, 17-trione, were separated. Inspection of their mass and nuclear magnetic resonance spectra showed that elimination of hydrogen at C-2 in Δ¹-dehydrogenation is stereoselectively β.