Constitution of kanugin—Part I
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By the oxidation of kanugin with potassium permanganate in acetone solution 4-o-methylresorcylic acid (I) and a neutral compound (II) containing methoxyl groups and having the formula C7H8O2 or C11H14O3 have been obtained. Hydrolysis with alcoholic alkali yielded an acid which seemed to be impure (I). The presence of a resorcinol unit in the molecule seemed to be thus established. Demethylation of kanugin gave rise to nor-kanugin. It had the properties of a flavonol (C16H12O7) and gave bright colours in alkaline buffer solutions. When its crystalline acetate was methylated a new methyl ether which was different from kanugin was produced. It was therefore concluded that by the action of hydriodic acid, besides demethylation some other changes were brought about.