ABSTRACT
This study was designed to study the chemical constituents from bulbil of Dioscorea opposite Thunb.. Four compounds were isolated by silica gel column chromatography. On the basis of physic-chemical characters and spectroscopic data analysis, these compounds were identified as lyzalkaloid (3,4-dihydro-6-hydroxy-4-methyl-6H-pyrido[6,5-b]indol-5(1H)-one) (1), anoectochine (2), ginsenine (3), and 2-hydroxy-3-(1H-indol-3-yl) propanoic acid methyl ester (4). Compound 1 is a new indole alkaloid, named as lyzalkaloid. Compounds 2-4 were isolated from this plant for the first time. The cytotoxic activities were assessed by MTT assay. All compounds exhibited the cytotoxic activity against HepG2 and MDA-231 with IC50 values of over 100 μmol·L-1, respectively. All compounds show no significant cytotoxic activities against HepG2, MDA-231 cancer cell.
ABSTRACT
The chemical constituents of Dioscorea opposite Thunb. were isolated and purified by Diaion HP-20, Sephadex LH-20, Toyopearl HW-40, MCI Gel CHP-20, ODS, silica gel column chromatography and semi-preparative-HPLC. Nine compounds were found and their structures were elucidated by spectral data and physicochemical properties, which were identified as 2-(1',2',3'-trihydroxybutyl-4'-O-α-D-glucopyranoside)-6-(2",3",4"-trihydroxybutyl)-pyrazine (1), uracil (2), xanthine (3), hypoxanthine (4), thymine (5), adenosine (6), uridine (7), inosine (8), and 5'-deoxy-5'-methylsulphinyladenosine (9). The compound 1 is a new pyrazine derivative, and the compound 3-5, 8, 9 are found in this plant for the first time.