[Studies on the chemical constituents from aerial parts of Gynura divaricata].

OBJECTIVE: To study the chemical constituents from aerial parts of Gynura divaricata. METHODS: The constituents were isolated on silica gel column chromatography, preparative TLC and Sephadex LH-20 column chromatography, identified by physicochemical properties and the structures were elucidated by spectral analysis. RESULTS: 10 compounds were isolated and identified as 2-(1', 2', 3', 4'-tetrahydroxybutyl)-6-(2", 3", 4"-trihydroxybutyl)-pyrazine (1), 2-(1', 2', 3', 4'-tetrahydroxybutyl)-5-(2", 3", 4"-trihydroxybutyl) -pyrazine (2), nicotinic acid (3), 5-hydroxy-picolinic acid(4), methyl-5-hydroxy-2- pyridinecarboxylate (5), adenosine (6), uridine (7), stigmasterol-5-O- beta-D-glucoside (8), dibutyl terephthalate (9), methyl chlorogenate (10). CONCLUSION: Compounds 1, 2, 5, 9, 10 are obtained from this genus for the first time, Compounds 3, 4 are obtained from this plant for the first time.