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The stems of Cotoneaster oligantha A. Pojark., after extraction with benzene and chloroform, were steeped in methanol. The methanolic extract was concentrated to small volume, and the chlorophyll was precipitated with water. The aqueous methanolic filtrate was chromatographed on columns of polyamide. Elution was performed with methanol of increasing concentration. The 70% methanol fractions contained mainly flavonoid (I) and the 50% methanol fractions flavonoid (II). These substances were purified by preparative chromatography on paper in 15% acetic acid and by repeated crystallization from 30% ethanol. Substance (I) consisted of light yellow crystals with mp 216-218°C, [~]~-97 ° (c 0.4; dimethylformamide), %max 254, 310, 360 nm. Substance (II) consisted of faintly yellowish crystals with mp 178-180°C, [a]~-31 ° (c 0.4; dimethylformamide), %max 259, 340, 360 nm. On the basis of UV spectroscopy with diagnostic reagents [i], the products of acid [2] and enzymatic hydrolysis, differential IR spectroscopy, and molecular rotations [3], it was established that flavonoid (I) is quercetin 3-O-B-D-glucopyranoside, and flavonoid (II) is quercetin 3-O-B-D-glucopyranosyl(l-~6)glucopyranoside. LITERATURE CITED

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