NOVEL STEROID COMPOUND CONTAINING KETONE GROUP AT 23-POSITION THEREOF, ITS PRODUCTION, USE THEREOF IN PRODUCTION OF 20-KETOPREGNANE COMPOUND AND ITS INTERMEDIATE

摘要

Compounds (I): …IMAGE… in which:… R1 is hydrogen or methyl,… R2 is methyl or ethyl,… the nuclei A, B, C and D carry optionally one or more double bonds and are optionally substituted by one or more functional groups or by one or more atoms or radicals,… R is halogen, hydroxyl, alkoxy, aralkoxy, alkylthio, arylthio, aralkylthio or …IMAGE…