[Diterpenoid alkaloids from Aconitum gymnandrum].

Aconitum gymnandrum maxim. (ranunculaceae) is used as an herbal medicine in Tibet area. A new diterpenoid alkaloid, gymnandine (I) along with known alkaloids 14-acetyl-8-O-methyltalatisamine (II), acoforine (III), columbidine (IV), aconitine (V), ranaconitine (VI), talatizidine (VII), isotalatizidine (VIII), gymnanconitine (IX), talatisamine (X), and atisine HCI (XI) have been isolated from this unique species. The structure of I is determined on the basis of spectral evidences and comparison of the 13CNMR spectrum with that of denudatine. II has not been previously reported as a natural product and III-VII were isolated from this plant for the first time.