Synthesis of 5β,17α-19-norpregn-20-yne-3β,17-diol and of 5β,17α-19-norpregn-20-yne-3α,17-diol, human metabolites of norethindrone

Abstract A convenient synthesis of both 5β, 17α-19-norpregn-20-yne-3β,17-diol (1) and 5β,17α-19-norpregn-20-yne-3α, 17-diol (2) in multigram quantities from estr-4-ene-3, 17-dione is reported. Full characterization of these often-cited human melaholites of norethindrone is presented for the first time.