M. Iwao et al., A SYNTHESIS OF PYRROLOPHENANTHRIDONE ALKALOIDS VIA CONSECUTIVE DIRECTED LITHIATION AND PALLADIUM-CATALYZED CROSS-COUPLING REACTIONS, Heterocycles, 38(8), 1994, pp. 1717-1720
A short and convergent synthesis of pyrrolophenanthridone alkaloids, s
uch as anhydrolycorin-7-one, oxoassoanine, hippadine, and pratosine, w
as developed by using directed lithiation and palladium-catalyzed cros
s-coupling as key reactions. Anhydrolycorin-7-one was converted to an
antitumor alkaloid, kalbretorine, via directed lithiation and hydroxyl
ation reactions.