Isolation and Structural Elucidation of Chemical Constituents of Corydalis Rhizoma / 中国实验方剂学杂志

ABSTRACT

Objective: In order to clarify the characteristic chemical constituents and furnish applicable information to the basic research and quality control research related to the chemistry of traditional Chinese medicines for Corydalis Rhizoma,this paper investigated the chemical constituents of Corydalis Rhizoma extensively. Method: The dried-up and pulverized plant materials were extracted using 95% EtOH as solvent,the EtOH extract was fractionated using different solvents to afford the EtOAc-soluble and n-BuOH-soluble portion,respectively,among others. These two portions were subjected to procedures of isolation and purification on silica gel or ODS column chromatographies to afford monomers. 1D and 2D NMR and MS methods,along with comparison with the data of literatures,were used to identify the structures. Result: Twelve compounds,all belonging to alkaloids,were isolated and identified as d-corydaline(1),tetrahydrocoptisine(2),tetrahydropalmatine(3),tetrahydrocolumbamine(4),corybulbine(5),tetrahydrojatrorrhizine(6),dehydrocorydaline(7),dehydroglaucine(8),8-oxodihydrocoptisine(9),protopine(10),taxilamine(11),and pontevedrine(12). Of these compounds,the structure of 12 was a revised structure which was assigned by combined examinations of their 1D and 2D NMR spectra and MS data. Conclusion: Compounds 6 and 11 were reported from Corydalis Rhizoma for the first time. The structure of pontevedrine was verified as 1,2,9,10-tetramethoxy-6-methyl-4H-dibenzo[de,g]quinoline-4,5(6H)-dione.