Chemical Transformation of Protoberberines. XVII. Biomimetic Introduction of an Oxy Functionality at the C-10 Position in the Benzo[c]phenanthridine Skeleton : Synthesis of 2, 3, 7, 8, 10-Pentaoxygenated Benzo[c]phenanthridine Alkaloids, Chelilutine and Sanguilutine

Abstract

An efficient and biomimetic introduction of an oxy functionality at the C-10 position in the benzo[c]phenanthridine skeleton was developed by regioselective oxygenation with salcomine-oxygen. This biomimetic procedure was successfully applied to a synthesis of 2, 3, 7, 8, 10-pentaoxygenated benzo[c]phenanthridine alkaloids, chelilutine (8) and sanguilutine (18), from the corresponding 2, 3, 7, 8-tetraoxygenated benzo[c]phenanthridines.