Also -in. Chem. [ad. F. xanthine, f. Gr. ξανθός yellow: see -INE5.] A substance (C5H4N4O2) allied to uric acid, found in various organs and secretions of the animal body; originally called xanthic oxide (see XANTHIC 1 a), from its forming a lemon-yellow compound with nitric acid.
1857. G. Bird, Urin. Deposits (ed. 5), 46. This interesting body … bears so close a resemblance to xanthine or uric oxide, that Scherer has named it hypoxanthine.
1862. H. Bence Jones, in Jrnl. Chem. Soc., XV. 78 (heading). On a Deposit of Crystallized Xanthin in Human Urine.
1880. J. W. Legg, Bile, 582. The liver contained … leucin, tyrosin, and xanthin.
1887. A. M. Brown, Anim. Alkaloids, 76. Xanthine may be extracted from muscular tissue in the same way as the sarkine.
attrib. and Comb. 1868. Watts, Dict. Chem., V. 1050. Xanthine … was discovered by Marcet in a urinary calculus weighing only 8 grains. Liebig and Wöhler afterwards found it in a larger calculus weighing between 18 and 20 grammes; these are the only known examples of xanthine calculi.
1873. Ralfe, Phys. Chem., 93. Dr. Bence Jones has recorded an interesting case of xanthin gravel occurring in a lad aged nine and a half years.
1883. Science, 23 Feb., 75/1. By heating xanthine-silver [= the silver-compound of xanthine] with methyl iodide, a methyl group was introduced.
1897. Trans. Amer. Pediatric Soc., IX. 123. Convulsive seizures,… produced by the action of the poisonous xanthin bodies on the nerve centres.
1907. Sat. Rev., 16 March, 338/1. So called food reformers … bandy about their catchwords—flesh-forming,… xanthin-forming and the like.
Hence Xanthinine, ǁ Xanthinuria (see quots.).
1868. Watts, Dict. Chem., V. 1051. Xanthinine. C4H2N2O2…. A base produced … by heating thionurate of ammonium to 200°…. On boiling the resulting mass with water, the xanthinine remains as a yellow powder.
1890. Billings, Nat. Med. Dict., Xanthinuria, passage of xanthin in the urine.
