RESUMO
13beta-Ethyl-3-methoxy-17beta-ol-8,14-seco-1,3,5(10),8-gonatetraen-14-one (IIIa) was isolated and its participation in the well-known acidic cyclization process was established.
Assuntos
Gonanos , Secoesteroides , Acetatos/síntese química , Fenômenos Químicos , Química , Cromatografia em Camada Fina , Ciclização , Gonanos/síntese química , Cinética , Espectroscopia de Ressonância Magnética , Espectrofotometria Infravermelho , Espectrofotometria UltravioletaRESUMO
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.
Assuntos
Flavobacterium/enzimologia , Gonanos/biossíntese , Hidroxiesteroide Desidrogenases/metabolismo , Mycobacterium/enzimologia , Nocardia/enzimologia , Saccharomyces/enzimologia , 17-Cetosteroides/biossíntese , Boroidretos , Sistema Livre de Células , Fenômenos Químicos , Química , NAD/metabolismo , Oxirredução , Secoesteroides/biossínteseRESUMO
Yeasts can advantageously be utilized for the production of the 17beta-hydroxy-derivative, from 3-methoxy-8,14-seco-1,3,5(10),9(11)-estratetraene-14,17-dione (14,17-dione) while 14alpha-hydroxy and 14alpha,17beta-dihydroxy-derivatives are also formed. The biochemical properties of yeasts' enzymes responsible for the formation of the two monohydroxy-derivatives have been studied in detail. In the cell-free extract of Saccharomyces the presence of two hydroxysteroid oxidoreductases could be detected. The first enzyme forms 3beta,17beta-dihydroxy-derivative from 5alpha-androstane-317-dione. This enzyme is responsible for the formation of 17beta-hydroxy-derivative from 14,17-dione. The second enzyme forms 3alpha-hydroxy-derivative from 5beta-androstanedione as well as 14alpha-hydroxy-derivative from its 14,17-dione. The cofactor of both enzymes is pyridine nucleotide. The two enzymes possessing different properties can selectively be inhibited.
