Stereoselective synthesis of pentacyclic steroids functionalized at C-11

We set out to describe an efficient and versatile method for preparing pentacyclic steroids diversely substituted at C-11 from cholic acid, via a stereoselective epoxidation and the epoxide opening as the key steps. The characteristic 1H and 13C NMR spectroscopic features of the synthesized compounds are reported.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A stereoselective synthesis of pentacyclic steroids is described. ► The key step is a stereoselective epoxide-opening lactonization. ► Various substituents can be introduced at the C-11 position of the steroidal skeleton.