[Isolation and identification of flavonoids from Spatholobi Caulis]

The chemical compounds in water extract of Spatholobi Caulis were further studied. The compounds were systematically isolated and purified by using various separation and analysis techniques including silica gel, macroporous adsorptive resins and Sephadex LH-20 column chromatographies, as well as reversed phase high-performance liquid chromatography(RP-HPLC). Twenty-three flavonoids and one chromone were identified by the spectroscopic analysis techniques combining their physicochemical properties, they were identified as isoduartin(1), sativan(2), 8-O-methylretusin(3), 7-hydroxydihydroflavone(4), odoratin(5), butesuperin A(6), biochanin A(7), 3'-methoxydaidzein(8), 7-hydroxychromone(9), calycosin(10), naringenin(11), dihydrocajanin(12),(6 aR,11 aR)-maackiain(13), 2'-hydroxygenistein(14),(6 aR,11 aR)-medicarpin-3-O-glucopyranoside(15),(-)-epiafzelechin(16),(-)-catechin(17),(-)-epicatechin(18), 4',8-dimethoxy-7-O-β-D-glucopyranosylisoflavone(19), ononin(20),(-)-gallocatechin(21), rutin(22), daidzin(23) and sphaerobioside(24). Compounds 4, 6, 8, 9, 11, 12, 14-16, 19 and 22-24 were isolated from Spatholobi Caulis for the first time.