Process for the preparation of 17 beta -[(1-oxoheptyl)oxy]-19-norpregn-4-en-20-yn-3-one (norethisterone oenanthate) and esters thereof and pharmaceutical compositions containing these

摘要

A process for the preparation of norethisterone esters of the general formula I <IMAGE> in which R is a straight-chain or branched alkyl, alkene or alkenyl group with 1-25 C atoms, in which norethisterone of the general formula II <IMAGE> is reacted with a suitable fatty acid in the presence of a condensing agent and of a suitable base in an aprotic solvent at ambient temperature, is described. Also described are the contained norethisterone oenanthate and related esters which have long-lasting contraceptive properties, as well as pharmaceutical compositions and contraceptives containing these.