Aminosteroids. Part 5. Synthesis of the four isomeric 3,11-diamino-5α-pregnanes

Abstract

Preparation of the four isomeric 3,11-diamino-5α-pregnanes is reported. Three (3β,11α-, 3α,11α-, and 3α,11β-) were prepared from 5α-pregnane-11,20-dione obtained from 20-oxo-5α-pregnane-3β,11α-diyl diacetate. The fourth (3β,11β-) was prepared from 11-oxo-5α-pregnan-3β-yl acetate which is also available from 5α-pregnane-11,20-dione, though for convenience another source was used.

The equatorial amino-groups (3β- and 11α-) were formed by alkali-metal reduction of the oximes; the axial 3α-amino-group by reduction of the 3α-azide; and the axial 11β-amino-group by catalytic hydrogenation of the oxime.