[Study on Chemical Constituents of Oldenlandia diffusa].

OBJECTIVE: To study the chemical constituents of Oldenlandia diffusa. METHODS: The chemical constituents were isolated and purified by silica gel and Sephadex LH-20 column chromatography as well as recrystallization method, and their structures were elucidated on the basis of physical and spectral analyses. RESULTS: Nine compounds were isolated and their structures were identified as quercetin (1), kaempferol (2), scopoletin (3), 2-hydroxy-3-methylanthraquinone (4), 2-hydroxy-l-methoxyanthraquinone (5), α-linolenic acid (6), vanillic acid (7), p-hydroxyphenylethanol (8) and, β-sitosterol (9). CONCLUSION: Compound 6 is obtained from this genus for the first time. Compounds 7 and 8 are obtained from this plant for the first time.