Pterocarpan Constituents Of Caragana Changduensis

Caragana changduensis is a shrub of genus Caragana Fabra.,Leguminosae,mainly distributed in Tibet and Qinghai province. C. Changduensis of which Tibetanname is zuomuxing, has a profound medicinal history in Tibetan traditional medicine.Its rhizome has the efficacy of promoting blood flow, reducing blood pressure andeliminating inflammation, which can be treated with plethora, hypertension,catamenia disorder for internal use while bruises and contused wound for external use.Systematic isolation of chloroform extract of C. changduensis was carried out.Eighteen compounds were obtained by preparative chromatography methods of silicagel, Toyopearl, PTLC, et al. Based on UV, IR, MS, NMR and X-ray crystaldiffraction, ten of them were identified as fallows, 8 pterocarpans:Homopterocarpin(Can-6), 3-Hydroxy-8,9-dimethoxypterocarpan(Can-10) ,3-Hydrox-y-4,9-dimethoxypterocarpan (Can-11), 4-methyoxy-maackiain(Can-12), Medicarpin(Can-13), Maackiain(Can-14), 3,4-dihydroxy-9-methoxypterocarpan(Can-15), 3,4-di-hydroxy-8,9-methylenedioxypterocarpan(Can-16); 2 isoflavones: Olibergin A (Can-17), Cajanin(Can-18). The structures of the others are being identified. CompoundsCan-6, Can-10, Can-12, Can-15, Can-16, Can-17 are isolated from genus Caraganafor the first time. A special phenomenon of pterocarpan constituents existing in C.Changduensis have been discovered for the fist time. The chromatography andspectroscopy property of them have been discussed.