Preparative isolation and purification of two new isomeric diterpenoid alkaloids from Aconitum coreanum by high-speed counter-current chromatography

Abstract: Preparative high-speed counter-current chromatography (HSCCC) coupled with evaporative light scattering detection (ELSD) was used to isolate and separate bioactive constituents from the roots of Aconitum coreanum. Two new diterpenoid alkaloid isomers were successfully separated for the first time by HSCCC with an optimized two-phase solvent system composed of ethyl acetate–n-butanol–methanol–2% acetic acid (3.5:1.5:2:4.5, v/v/v/v), 25.4mg of GFT (1) and 18.3mg of GFU (2) were isolated form 1g crude extract in one step HSCCC experiment. The purities of the two new compounds were all over 95% as analyzed by HPLC and their structures were identified by ESI–MS, 1H NMR, 13C NMR, and 2D NMR analysis. [Copyright &y& Elsevier]