Synthesis of 9,11-disubstituted 19-nor-steroids
Abstract
Reaction of a 9α-methyl-11-oxoestrone derivative (I) with methylmagnesium bromide gave the 11α-methyl-11β-hydroxy-compound (II). This could be dehydrated with acid to an olefin, shown to be an 11,11-dimethyl-Δ8,9-steroid, or converted into its acetate and pyrolysed to give a 9α-methyl-11-methylene derivative as the major product. Hydrogenation of this last material gave a 9α, 11β-dimethyl derivative. All three substituted skeletons were converted into other 19-nor-compounds, in particular, the 17α-ethynyl-17β-hydroxyl-4-en-3-ones (XVII), (XXV), and (XXXIX).