- Microbial transformation of 17α-ethynyl- and 17α-ethylsteroids, and tyrosinase inhibitory activity of transformed products
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The microbial transformation of the 17α-ethynyl-17β- hydroxyandrost-4-en-3-one (1) (ethisterone) and 17α-ethyl-17β- hydroxyandrost-4-en-3-one (2) by the fungi Cephalosporium aphidicola and Cunninghamella elegans were investigated. Incubation of compound 1 with C. aphidicola afforded oxidized derivative, 17α-ethynyl-17β- hydroxyandrosta-1,4-dien-3-one (3), while with C. elegans afforded a new hydroxy derivative, 17α-ethynyl-11α,17β-dihydroxyandrost-4-en-3-one (4). On the other hand, the incubation of compound 2 with the fungus C. aphidicola afforded 17α-ethyl-17β-hydroxyandrosta-1,4-dien-3-one (5). Two new hydroxylated derivatives, 17α-ethyl-11α,17β- dihydroxyandrost-4-en-3-one (6) and 17α-ethyl-6α,17β-dihydroxy- 5α-androstan-3-one (7) were obtained from the incubation of compound 2 with C. elegans. Compounds 1-6 exhibited tyrosinase inhibitory activity, with compound 6 being the most potent member (IC50 = 1.72 μM).
- Choudhary, M. Iqbal,Sultan, Sadia,Khan, Mahmud Tareq Hassan,Rahman, Atta-ur
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- STEROID SPIROLACTONIZATION
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A steroid comprising a 17-spirolactone or corresponding open lactone structure is obtained by carbonylation of a 17-alkenyl or 17-alkynyl substrate. A 17-alkenyl intermediate may be prepared by semi-hydrogenation of a 17-alkynyl group. Multiple reaction schemes are disclosed for preparation of a 3-keto-9,11-epoxy-17-spirolactone steroid such as eplerenone. Novel intermediates are also disclosed, as well as steps for forming such novel intermediates, or converting them to further intermediates or products, by semi-hydrogenation, carbonylation, 6,7-dehydrogenation, furylation or other transformations or combinations thereof.
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- Synthesis and NMR Studies of Some Steriodal Isoxazoles
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A short synthesis of 17α-pregna-2,4-dien-isoxazol-17β-ol (1) is described using mild reaction conditions and with a high overall yield.The equilibrium between keto-enolic forms has been studied by 1H NMR methods.Complete assignments of all the resonances in the 1H and 13C NMR spectra of Danazol have been made using a variety of one and two-dimensional correlation methods. 13C NMR spectra of all the intermediate and related model compounds were also assigned. Key words: Anabolic Agents, Isoxazolinic Steroids, 17α-Pregna-2,4-dien-isoxazol-17β-ol, Synthesis, NMR Spectra
- Giacopello, Sergio,Deluca, Monica E.,Seldes, Alicia M.
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p. 891 - 897
(2007/10/02)
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