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