Chemical Study of Alkaloids from Corydalis bungeana

Abstract

From the herbs of Corydalis bungeana, 16 alkaloids were isolated; 3 of them were identical with acetylcorynoline (2), corynoline (5), protopine (9), which had been obtained before from this plant. A further 11 known alkaloids: dihydrosanguinarine (1), acetylisocorynoline (3), 11-epicorynoline (4), corycavine (6), bicuculine (7), 12-hydroxycorynoline (8), scoulerine (12), cheilanthifoline (13), yuziphine (14), isoboldine (15), noryuziphine (16) were isolated for the first time from this plant. The tenth, named (+)-bungeanine, is a new alkaloid. Its structure has been established to be N-nor-5,14-dehydroacetylcorynoline. The conformation of (+)-bungeanine in solution is also discussed.