Epalons: 6-Substituted Derivatives of 7-Norepiallopregnanolone

The target compounds (3α-hydroxy-5,6-epoxy-7-nor-5α-pregnan-20-one, 3α-hydroxy-5,6β-epoxy-7-nor-5β-pregnan-20-one and 3α-hydroxy-7-nor-5α-pregnane-6,20-dione) were prepared from 5,6β-dihydroxy-20-oxo-5α-pregnan-3β-yl acetate via the corresponding 5,6-seco acid and 3β-acetoxy-20-oxo-7-nor-5β,6α-pregnane-6,5-carbolactone-actone. Intermediate 3β-hydroxy-7-norpregn-5-en-20-one was converted into the corresponding 5α,6α and 5β,6β epoxides. The latter was isomerized into 3β-hydroxy-7-nor-5α-pregnane-6,20-dione. The configuration of the 3β-hydroxy group in these compounds was inverted by Mitsunobu reactions.