Indole alkaloids with self-activated sp2 C-H bond from Alstonia scholaris

Abstract Alstoniascholarines T (1) and U (2), two novel monoterpenoid indole alkaloids from Alstonia scholaris, enabled an unexpected deuteration via activation of the sp2 C-H bond without any catalysts under room temperature. Structurally, alkaloid 1 represented the rare nor-C17 strychnan indole, and compound 2 possessing highly modified strychnan skeleton with an additional furan ring between C-16/19. This finding presented the detailed description of natural products with sp2 C-H self-activation and deuteration, which may shed a light on the C-H functionalization blocked by the expensive metal catalysts and/or rather harsh reaction conditions.