xanthine

American  

[zan-theen, -thin] / ˈzæn θin, -θɪn /

noun

Biochemistry, Chemistry.

1. a crystalline, nitrogenous compound, C 5 H 4 N 4 O 2 , related to uric acid, occurring in urine, blood, and certain animal and vegetable tissues.

2. any derivative of this compound.

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xanthine British  

/ ˈzænθiːn, -θaɪn /

noun

1. a crystalline compound related in structure to uric acid and found in urine, blood, certain plants, and certain animal tissues. Formula: C 5 H 4 N 4 O 2

2. any substituted derivative of xanthine, esp one of the three pharmacologically active methylated xanthines, caffeine, theophylline, or theobromine, which act as stimulants and diuretics

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xanthine Scientific  

/ zăn′thēn′,-thĭn /

1. Any of various purines having two oxygen atoms attached to the six-member ring of carbon and nitrogen atoms. Xanthines include caffeine, theophylline (a toxic alkaloid found in tea leaves), and theobromine (a toxic alkaloid found in cocoa).

2. The simplest of this class of compounds, forming yellowish-white crystals. It is produced in the body as an intermediate stage in the breakdown of purines to uric acid. It is also found in blood and in certain plants. Chemical formula: C ₅ H ₄ N ₄ O ₂ .

3. Any of several derivatives of this compound.

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Etymology

Origin of xanthine

From French, dating back to 1855–60; xantho-, -ine ²

Example Sentences

Dr. Ball purified xanthine oxidase, an enzyme necessary for oxidation of food in the body; found it consisted of a protein fraction and a non-protein fraction containing phosphorus, nitrogen, Vitamin B2.

From Time Magazine Archive

The xanthine bases are closely related to uric acid.

From The Chemistry of Food and Nutrition by Duncan, A. W.

Both theobromine and caffeine, its methyl derivative, have been made from xanthine, which itself can be formed from guanine, a constituent of guano.

From Scientific American Supplement, No. 415, December 15, 1883 by Various

It comprises the xanthine group and the uric acid group of bodies.

From The Chemistry of Food and Nutrition by Duncan, A. W.

The yellow deposit which is obtained in this way, is not pure xanthine, as it contains a rather considerable quantity of oil.

From The Art of Perfumery And Methods of Obtaining the Odors of Plants by Piesse, George William Septimus