ABSTRACT
Objective: To study the chemical constituents from the roots of Imperata cylindrica var. major. Methods: The chemical constituents were isolated and purified by combination of silica gel, Sephadex LH-20, polyamide, and ODS column chromatography. The structures of the isolated compounds were identified by means of spectral data and physicochemical property. Results: Twelve phenolic compounds were isolated from I. cylindrica var. major and identified as 4,7-dimethoxy-5-methylcoumarin (1), 7-hydroxy-4-methoxy-5-methylcoumarin (2), 7- O-β- D-glucopyranosyl-4-methoxy-5-methylcoumarin (3), 6-hydroxy-5-methoxyflavone (4), 5-methoxyflavone (5), 5,7-dihydroxy-8-methoxyflavone (6), 4-hydroxybenzaldehyde (7), 4-hydroxy-cinnamic acid (8), 4-hydroxy-3-methoxybenzoic acid (9), 3,4-dimethoxyphenyl- O-β- L-rhamnopyranosyl-(1β6)-β- D-glucopyranoside (10), impecyloside (11), and graminone A (12). Conclusion Compounds 2β4, 6, and 10 are obtained from this plant for the first time. © 2013 Tianjin Press of Chinese Herbal Medicines.