Aromatization of 7β,17β-diacetoxy-4-methyleneandrost-5-ene

Abstract

Treatment of 7β, 17β-diacetoxy-4-methyleneandrost-5-ene with hydrobromic acid in glacial acetic acid affords 17β-acetoxy-1,4-dimethyloestra-1,3,5(10)-triene rather than an anthrasteroid. The incorporation of deuterium from deuterium bromide and deuterioacetic acid on the C-4 methyl group is consistent with a methyl group migration from C-10 to C-1 during the rearrangement. A minor amount of 17β-acetoxy-3,4-dimethyloestra-1,3,5(10)-triene is also formed in the rearrangement.