Chemical constituents from Spatholobus sinensis

Spatholobus sinensis is a plant of the Spatholobus genus (Leguminosae family). Its caulis are used as “ji-xue-teng” regionally. However, to our knowledge, no phytochemical investigation on S.sinensis has been reported to date. In this study, eight compounds were isolated from the ethanol extract of the caulis of S.sinensis, by solvents extraction and column chromatography methods. By analysis of their physic-chemical constants and spectral data, the structures of 8 compounds were identified as spatholosineside A (1), 2′,4′,5,7-tetrahydroxyisoflavone (2), isoliquiritigenin (3), lupinalbin A (4), coumestrol (5), naringenin (6), protocatechuic acid (7), leonuriside A (8). Compound 1 is a new compound.