Xanthic oxide, xanthine

Xanthic acid, isopropyi-, potassium sait. See Potassium isopropyi xanthate Xanthic acid, pentyi-, potassium sait. See Potassium amyi xanthate Xanthic oxide. See Xanthine Xanthine... 

Wohler and Liebig prepared the derivatives of uric acid by fairly simple oxidation reactions with nitric acid etc., and reduction reactions, and speculated on the relations of the compounds and their constitution . Xanthic oxide they correctly found contains an atom of oxygen less than uric acid its present name xanthine was proposed by Gmelin, Allantoin was discovered by Buniva and Vauquelin and further investigated by Wohler. Wohler and Liebig obtained it by oxidising uric acid with a suspension of lead dioxide. 

Xanthine (xanthic oxide) was discovered by Marcet (1819 see Vol. Ill, p. 707), hypoxanthine in spleen by T. Scherer. Strecker discovered what he called sarkin in flesh and showed that it is the same as hypoxanthine, C5H4N4O. Thudichum (1879) Salomon independently discovered in... 

Marcet discovered in a urinary calculus a substance which he called xanthic oxide, since it was soluble in alkalis and on evaporation with nitric acid gave a yellow substance. Its correct formula, C5H4O2N4, was first found by Wohler and Liebig, and since it contains one atom of oxygen less than uric acid, Berzelius called it urous acid (Harnige Saure). It is now called xanthine it can be obtained by reducing uric acid with sodium amalgam and is colourless when pure. ... 

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