Studies on Chemical Constituents of Grewia biloba II

Objective:To investigate the chemical constituents of Grewia biloba.Method:Individual con-stituents,isolated and repeatedly purified on silica gel and Sephadex LH-20 column chromatography,were identified by physicochemical constants and structurally elucidated by spectral methods.Result:Four compounds were isolated and identified as:3′,4′,5,7-tetrahydroxy-7-ethoxyflavone(1),1α,3β,23-trihydroxyolean-12-en-28-oic acid(2),6-C-glucosyl-quercetin(3),6-C-glucosyl-3,3′,4′,5,7-pentahydroxyflavanone(4).Conclusion:Compound 1 is a new natural product,others are isolated from the genus Grewia for the first time.