Macrophyllionium and macrophyllines A and B, oxindole alkaloids from Uncaria macrophylla.

摘要: An unusual oxindole alkaloid inner salt, macrophyllionium (1), and a pair of new tetracyclic alkaloids, macrophyllines A (2) B (3), together with six known were isolated from the aerial parts Uncaria macrophylla. Corynantheidine (8) exhibited moderate cytotoxicity against HL-60 SW480 cells IC(50) values 13.96 23.28 mu M, respectively. Dihydrocorynantheine (9) significant vasodilating activity phenylephrine-induced contraction in rat thoracic aorta rings (IC(50) = 6.73 g/mL). In addition, compounds 2, 6, 9 showed weak inhibitory action on KO-induced contraction.