Abstract
Rubus coreantim (Rosaceae), which has been used in oriental traditional medicine as the remedies for impotence, pollution and premature ejaculation, bet-wetting and frequ ency of urination. is a fruit drug cultivating throughout southern Korea. The leaves of Rubus coreanum were extracted with 80% acetone. The extracts were separated by Ambellite XAD-2, Sephadex LH-20. MCI-gel CHP 20P and Cosmosil 75 C$_{18}$ OPN. And three flavonoids were isolated. The structures of these compounds were elucidated as quercetin-3-O-${\beta}$-D-glueuronopyranoside(l). quercetin-3-O-${\beta}$-D-glueuronopyranosyl methyl ester(2), quercetin-3-O-${\beta}$-D-xylopyranosyl-(2${\rightarrow}$1)-${\beta}$-glucopyranoside(3) on the basis of physicochemical and spectroscopic evidences.