Epalons: 6-substituted derivatives of 7-norepiallopregnanolone

The target compounds (3 alpha-hydroxy-5,6-epoxy-7-nor-5 alpha-pregnan-20-one, 3 alpha-hydroxy-5,6 beta-epoxy-7-nor-5 beta-pregnan-20-one and 3 alpha-hydroxy-7-nor-5 alpha-pregnane-6,20-dione) were prepared from 5,6 beta-dihydroxy-20-oxo-5 alpha-pregnan-3 beta-yl acetate via the corresponding 5,6-seco acid and 3 beta-acetoxy-20-oxo-7-nor-5 beta,6 alpha-pregnane-6,5-carbolactone-actone. Intermediate 3 beta-hydroxy-7-norpregn-5-en-20-one was converted into the corresponding 5 alpha,6 alpha and 5 beta,6 beta epoxides. The latter was isomerized into 3 beta-hydroxy-7-nor-5 alpha-pregnane-6,20-dione. The configuration of the 3 beta-hydroxy group in these compounds was inverted by Mitsunobu reactions. (C) 2000 Elsevier Science Ltd. All rights reserved.