ABSTRACT
Objective: To study the chemical constituents in the roots of Aconitum iochanicum Ulbr.Methods: The air-dried roots of A.iochanicum were powdered and extracted by methanol with a percolation method.After removing the solvent under reduced pressure, the crude extract was dissolved in1.5% HCl solution, and then extracted by ecetic ether.The acidic solution was basified to pH 9.0 by NaOH (5%) and extracted with ethyl acetate to obtain crude alkaloidal extract after the removal of ethyl acetate.The compounds were isolated and purified by column chromatography and identified based on spectral analysis (1H-NMR, 13C-NMR and MS).Results: Totally 18 compounds were isolated from A.iochanicum and characterized as 14-O-acetylsachaconitine (1), franchetine (2), crassicaudine (3), indaconoitine (4), 14-benzoyl chasmanine (5), 14-O-acetyltalatisamine (6), talatisamine (7), chasmannine (8), crassicauline A (9), bikhaconine (10), 13,15-dideoxyaconitine (11), crassicautine (12), kongboensine (13), liljestrandisine (14), ludaconitine (15), 8-deacetyl-yunaconitine (16), yunaconitine (17) and ouvrardiantine (18).Conclusion: It''s the first time to study the chemical constituents of A.iochanicum, and 18 diterpenoid alkaloids are isolated.