Bousigonine A and B, bis- and tri-indole alkaloids from Bousigonia mekongensis and their preventing high glucose-induced podocyte injury activity.

• Two novel bis- and tri-indole alkaloids were isolated from B. mekongensis. • The absolute configurations of 1 and 2 were established. • Their activity of preventing high glucose-induced podocyte injury was evaluated. Bousigonine A (1), an unprecedented eburnamine-voaphylline type dimeric indole alkaloid, and Bousigonine B (2), the first example of eburnamine-eburnamine-aspidospermine type trimeric indole alkaloid were isolated from Bousigonia mekongensis. Their structures were elucidated mainly by spectroscopic analysis and compared to published data. Their preventing high glucose-induced podocyte injury activity were evaluated for the first time, and compound 1 exhibited significant effect with EC 50 value of 2.5 μM. [ABSTRACT FROM AUTHOR]