A Novel Approach to the Stereocontrolled Synthesis of Steroid Side Chains Including the CD-Ring System: The First Total Synthesis of (+)-8α-(Phenylsulfonyl)des-AB-cholestane and Its Efficient Conversion into Grundmann's Ketone and Vitamin D3

Article abstract of DOI:10.1021/jo00376a049

A new stereocontrolled approach to steroid CD-ring system including side chain starting from an optically active indenedione 6 is described.The application of this finding allows for the asymmetric synthesis of des-AB-cholestane 3 and 8α-(phenylsulfonyl)des-AB-cholestane 37; from the latter Grundmann's ketone 25 and vitamin D₃ (27) were synthesized efficiently.