Steroids And Related Products .53. The Synthesis Of 11-Oxa Steroids .5. The Synthesis Of 17-Ethynyl-11-Oxatestosterone

The synthesis of 17-ethynyl-11-oxatestosterone, both from 11-oxa-5α-pregnane-3, 20-dione and, via a 3, 17-dioxygenated 9-oxo 9, 12-seco 11-nor 5α-androstan-12-oic ester, from 3β-acetoxy-17-hydroxy-5α-pregnan-12-one - two products available from hecogenin - is reported. The new hormone analogue shows significant progestational activity in the Clauberg test and relatively weak activity in a post-coital antifertility assay.