Diterpenoid Alkaloids from the Aerial Parts of Aconitum flavum Hand.-Mazz.

Sixteen diterpenoid alkaloids (DAs), including six aconitine-type alkaloids (5 and 9 - 13), seven 7,17-seco-aconitine-type alkaloids (1 - 4, 6 - 8), two napelline-type alkaloids (14 and 15) as well as one veatchine-type alkaloid (16), were isolated from the aerial parts of Aconitum flavum Hand.-Mazz. In which, flavumolines A - D (1 - 4) were four new ones, and flavumoline E (5) was reported as natural compound for the first time. Their chemical structures were elucidated by the analysis of extensive spectroscopic data. The inhibitory activities of these isolates on Cav3.1 low voltage-gated Ca2+ channel, NO production in LPS-activated RAW264.7cells, five human tumor cell lines, as well as acetylcholinesterase (AChE) were tested.