ABSTRACT
For the purpose of producing hydroxy-keto-seco-steroids in which hydroxyl group is attached to a carbon atom having the R-configuration, numerous biochemically active microorganisms were tested without any success. The hydroxysteroid oxidoreductase enzymes of the investigated bacterial, yeast and fungal strains were suitable only for the production of 17beta-ol-14-one and 14alpha-ol-17-one derivatives. The required compounds were prepared by combinations of enzymatic reactions with chemical reduction. (i) By hydroxysteroid oxidoreductase of Saccharomyces uvarum and Saccharomyces drosophilarum, 17beta-ol-14-one and 14alpha-ol-17-one derivatives of 14,17-dione, respectively, were obtained. (ii) The above compounds were acetylated then reduced by sodium borohydride. (iii) 14beta,17beta-diol-17-acetate and 14alpha,17alpha-diol-14-acetate were dehydrogenated by dehydroxysteroid oxidoreductase of Nocardia sp. and Mycobacterum sp., respectively, in the presence of steroid esterase. The reaction mixture contained either 14beta-ol-17-one or 17alpha-ol-14-one derivatives, since oxidation by hydroxysteroid oxidoreductase was limited to the hydroxyl group attached to a carbon atom having the S-configuration.
