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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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Continuing a study of the flavonoid composition of Artemisia transiliensis Poljak [1], we have isolated four flavonoid aglycones from an ethereal extract. Flavones and flavonols in which the OH group at CO) is substituted are stable to oxidation in alkaline solutions and can be obtained on acidification [2]. Using this method, the ethereal extract was treated successively with saturated NaHCOa solution and with a 10% solution of Na2CO s. The alkaline solutions were acidified and extracted with ether. From the bicarbonate extract by preparative paper chromatography using benzeneacetic acid-water (125 : 72 : 3) as solvent, we isolated quercetin 3-methyl ether with mp 259 ° C and a substance, II, with mp 255-256 ° C (from 70% ethanol), kma x 355, 266, 255 mg. In the cyanidin reaction, substance II gave a crimson coloration showing its flavonol nature. Spectral studies in the UV region with ionizing and complex-forming reagents showed the presence in the aglycone II of free OH groups at CU), C(a,) and C(4,). In an alkaline melt ofthesubstancepaper chromatography showed the presence of catechol and protocatechuic acid. IR spectroscopy showed that the aglycone II contains a methoxy group (2960, 2850 cm-1) located at C(3). Demethylation of the substance led to the formation of 7,8, 3', 4'-tetrahydroxyflavonol with mp 310-312 ° C [3]. Methylation of the aglcyone with diazomethane yielded a pentamethoxyflavone with mp 149-150 ° C. Thus, on the basis of the chemical and spectral studies substance II has been characterized as 7,8, 3', 4'-tetrahydroxy-3-methoxyflavone. It proved to be new, and we have called it transilitin. From the sodium carbonate solution we isolated genkwanin with mp 283 ° C and acacetin with mp 260-261 ° C.

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