Aporphine Alkaloids from Triclisia dictyophylla Diels by pH-Zone Refining Countercurrent Chromatography

Abstract

A new dimeric aporphine alkaloid, biscocsarmine, 2, together with lirioferine, 1, and cocsarmine, 3, were isolated from the ethanol extract of the stems of Triclisia dictyophylla Diels (Menispermaceae) using a preparative pH-zone refining CCC in a single step. The first solvent system family tested for this fractionation was hexane–ethyl acetate–methanol–water (HEMWat) at a series of solvent ratios, and hydrochloric acid and triethylamine at 5 mM as eluter/retainer. None of these HEMWat ratios, however, gave suitable K for the target alkaloids. Ethyl acetate–n-butanol–water (EBuWat) was tested instead and the selected solvent system was composed of ethyl acetate–n-butanol–water 5:5:10 (v/v), where triethylamine (60 mM) was added to the upper organic stationary phase as a retainer and hydrochloric acid (5 mM) to the aqueous mobile phase as an eluter. The chemical structures of the isolated compounds were elucidated based on comprehensive spectroscopic and spectrometric techniques. This is the first report of aporphine alkaloids in this plant species.