Azasteroids as Inhibitors of Rat Prostatic 5α-Reductase

Article abstract of DOI:10.1021/jm00378a028

A series of A-ring heterocyclic steroids has been prepared and tested for inhibition of rat prostatic steroid 5α-reductase in vitro.Strinkingly high inhibitory activity was found with a group of 17β-substituted 4-methyl-4-aza-5α-androstan-3-ones.These compounds were prepared from 3-keto-Δ⁴-precursors by oxidative (O3 or NaIO4-KMnO4) A-ring cleavage followed, in turn, by ring closure with an amine and hydrogenation over platinum catalyst.Other A-ring azasteroids were made by Beckmann rearrangement of oximes of 2-oxo-A-nor-, 3-oxo- and 4-oxo-5α-androstanes.An A-nor-2-oxo-3-azasteroid was prepared by oxidative decarbonylation of a precursor 2,3-dioxo-4-azasteroid with m-chloroperbenzoic acid.A-ring modifications of the 4-azasteroids included Δ¹-unsaturation, 2- and 4-substituents, and 3-carbonyl replacements.Side chains at the 17-position were varied with an emphasis on carboxylate derivatives (salts, esters, and amides).