THE SYNTHESIS OF A-NOR-19-NOR-DIETHYNYL STEROIDS

The synthesis of a potential anti-implanting agents for female, A-nor-19-nor-2, 17 α-diethynyl-5 α-androstane-2,17 β-diol dipropionate and its 18-methyl analog featured with a shortened approach was reported. 19-nor-4-androsten-3,17-dione and 17 β-hydr-oxy-19-nor-13 β-ethyl-4-androsten-3-one were used as the starting materials, respectively and then followed successfully with lithium ammonia reduction, oxidation, cyclization. and final ethynylation to afford the desired compounds.