5-α-雄烷

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: More particularly, a zinc and acetic acid cleavage of 5α-bromo-3β-hydroxy-6β,19-oxidoandrostan-17-one results in the formation of 3β,19-dihydroxy-5-androsten-17-one diacetate. Lithium tri-t-butoxyaluminum hydride reduction then results in the preparation of 5-androstene-3β,17β,19- triol 3,19-diacetate. The 17β-hydroxy group can now be converted to an ether using standard procedures to form, for example, 17β-methoxy-5-androstene-3β,19-diol diacetate or 17β-(4'-tetrahydropyranyloxy)-5-androstene-3β,19-diol diacetate. A catalytic hydrogenation then furnishes the corresponding 5α-androstane. Basic hydrolysis subsequently cleaves the esters to form the free 17-ether diols. In this manner the compounds, 17β-methoxy-5α-androstane-3β,19- diol and 17β-(4'-tetrahydropyranyloxy)-5α-androstane-3β,19- diol can be prepared. Oxidation results in the formation of the corresponding diones. Etherification thereof furnishes the mixed triethers.