Free Radical Macrocyclizations from Steroid-Derived Precursors

Article abstract of DOI:10.1021/jo00057a034

Stereoselective free radical addition reactions were studied using steroid-derived templates in an attempt to control product dispersity.Templates were prepared from bifunctional steroids appropriately substituted with initiating and terminating functionality.Free radical initiation in the presence of a polymerizable olefin resulted in the formation of macrocycles that had incorporated monomer.The yield of macrocycle formed was as 51percent for templates derived from lithocholic acid whereas templates derived from androstanolone failed to give significant amounts of macrocycles.The effects of variation of initiating and terminating functionality, steroid, and olefin on macrocycle size and yield were examined.