Studies On Alkaloids From Aconitum Sczukinii And Aconitum Sinomontanum Nakai

This dissertation focused on the in-depth phytochemical research of Aconitum sczukinii and Aconitum sinomontanum Nakai in which 16 compounds were isolated.The crude alkaloids were got by traditional cold-soaked extraction,dissolution with acid and deposition with alkali,and organic solvent extraction.The residue was isolated by silica gel chromatography including normal phase and reverse phase.The structures of all diterpenoid alkaloids were elucidated by HR-ESI-MS,IR,1D and 2D-NMR and compare with reported literatures.5 out of 10 come from Aconitum sczukinii were new compounds determined as sczukiniline A-E,including three hetidines C₂₀-diterpenoid alkaloids and two lycoctonines C₁₉-diterpenoid alkaloids.An ester group existed between C-12 and C-14,forming a D ring containing a lactone structure in sczukiniline A.The known compounds 50-53 were first isolated from Aconitum sczukinii.Six known diterpenoid alkaloids were isolated and identified from Aconitum sinomontanum Nakai.Among them,8-O-methylgigactonine（54）,anhydroly-coctonine（55）and finaconitine（56）were first found in this plant.In order to find compounds with promising anti-Alzheimer’s disease activity,the five new diterpenoid alkaloids isolated from Aconitum sczukinii were tested for acetylcholinesterase inhibitory activity.Unfortunately,none of these compounds showed acetylcholinesterase inhibitory activity.This study may play an important role in developing and popularizing the distinctive medicinal plants from Aconitum sczukinii and Aconitum sinomontanum Nakai,and provide scientific clue for the chemmotaxonomy of the Aconitum plants.