Oxidation of 3 beta- and 17 beta-hydroxysteroids by Nocardia rubra cells in heptane-water system.

Oxidation of cholesterol, beta-sitosterol, pregnenolone, androstenolone and 5-androsten-3 beta,17 beta-diol carried out by Nocardia rubra cells in a mixture of heptane-water (25:1 vol.) gave 4-en-3-oxo-steroids with the yield to 100% (cholesterol). Simultaneously oxidation of 17 beta-hydroxy group in androstendiol and in testosterone was observed as well.

Reduction of testosterone, androstendione and their derivatives by Aphanocladium album.

A strain of Aphanocladium album reduces the C-3 carbonyl group in testosterone or androstendione to to 3 alpha-allyl alcohol. In some derivatives of these steroids the same carbonyl group is reduced to allyl alcohol with stereospecificity, depending on whether chlorine at C-4 or a 17 alpha-methyl group is present. On the other hand, the presence of C-4 methyl group, a C-19 hydroxy group, a C-17 acetyl one, or a double bond conjugated with the 4-en-3- ketone system totally inhibits the formation of allyl alcohols at C-3. At the same time, the C-17 carbonyl group in androstendione or in its derivatives is reduced to a respective 17 beta-alcohol. In the derivatives with an additional 2-exomethylene group the double bond at this group is reduced.

Microbiological transformations. XI. The use of immobilized Rhodotorula mucilaginosa cells to reduce some ketones.

Rhodotorula mucilaginosa cells were immobilized by polymerizing acrylamide with the addition of a cross-linked agent, a catalyst and an initiator. This gel was used for the stereospecific reduction of acetophenone and alpha-acetylnaphthalene resulting chromatographically pure alcohols with absolute configuration S. When karen-3-dion-2,5 was used as substrate, four products were obtained. Androstenolone was reduced with 30% yield. Activity of the immobilized cells could be regenerated by glucose.