A directed metalation route to the zwitterionic indole alkaloids. Syntheses of indolo[2,3-a]quinolizine, flavopereirine, flavocarpine, and dihydroflavopereirine
A directed metalation route to the zwitterionic indole alkaloids. Syntheses of indolo[2,3-a]quinolizine, flavopereirine, flavocarpine, and dihydroflavopereirine