Steroids. Part XXIX. The structure of digacetigenin

Abstract

Digacetigenin is shown to be 12β-acetoxy-3β,14β-dihydroxypregn-5-ene-15,20-dione, and has been converted into digacetigenone 3-acetate [3β-acetoxy-14β-hydroxypregn-5-ene-12,15,20-trone], also obtained from purprogenin [3β,14β,15α-trihydroxypregn-5-ene-12,20-dione]. Mass spectra of digacetigenin and its 3-acetate show that the compound, previously regarded as homogeneous, contains some 5α,6-dihydrodigacetigenin, from which it cannot be separated by thin-layer chromatography on alumina or on silica; re-examination of the nuclear magnetic resonance spectrum of digacetigenin and comparison with that of 5α,6-dihydrodigacetigenin shows that the proportion of the latter is 20–25%.