Construction of pyrrolophenanthridinone scaffolds mediated by samarium(II) diiodide and access to natural product synthesis

Pyrrolophenanthridinone derivatives including the natural products were readily synthesized by samarium(II)-mediated reductive cyclization of aryl radical onto a benzene ring under mild reaction conditions. This methodology was applied to the concise synthesis of anhydrolycorinone, a natural pyrrolophenanthridinone and a precursor of hippadine and anhydrolycorine.

Graphical abstractDownload full-size imagePyrrolophenanthridinone derivatives including natural product were readily synthesized by samarium(II)-mediated reductive cyclization of aryl radical onto a benzene ring via a spirohexadienyl radical intermediate under mild reaction conditions. This methodology was applied to the concise synthesis of anhydrolycorinone, which can be transformed into hippadine and anhydrolycorine.