Studies on chemical constituents of Rheum glabricaule.

To study the chemical Constituents in the root of Rheum glabricaule.Compounds were isolated by various column chromatographies with sillica gel. Their structures were identified by spectral analysis (MS, 1HNMR, 13 CNMR) and chemical evidences.Seven compounds were isolated from this plant, including n-hexacosnic acid (I), palmitic acid (II), daucosterol (III), chrysophanol-8-Me ether (IV), citreorosein (V), chrysophanol 8-O-beta-D-glucopyranoside (VI) and 2,5-dimethyl-7-methoxychromone (VII).All above compounds are obtained from this plant for the first time.