Xanthine
- 2,6- Dihydroxypurin
- 2,6 (1H, 3H)- Purindion
- 2,6 (1H, 3H)- Purindiol
Colorless solid
Fixed
350 ° C.
Very slightly soluble in water (69 mg · l-1 at 16 ° C )
Attention
> 3333 mg · kg -1 ( LD50, mouse, oral)
Template: Infobox chemical / molecular formula search available
Xanthine is a naturally occurring substance of nucleotide metabolism. It is an intermediate in Purinabbau and is converted into uric acid by xanthine oxidase. In addition, xanthine is the lead compound of the group of xanthines to which the purine alkaloids caffeine, theobromine and theophylline are made from tea leaves, coffee beans, cocoa, kola nuts, maté and guarana.
Occurrence
Is an intermediate of xanthine Purinabbaus by hydroxylation at the positions 2 and 6; the resulting Dilactim tautomerizes doing a complete dilactam. It arises, for example, in the wine in small quantities by the self- digestion of yeast. Also in coffee beans, potatoes, tea leaves and Mate, the Argentinian national drink, it happens. There he is said to have a stimulating effect due to its special structure. In the human body contain some organs such as blood, muscle and liver xanthine, which is also excreted in the urine.
Properties
Xanthine is a colorless, crystalline solid which is good in ethyl acetate, acids and bases, very little ( 69 mg · l-1 ) of cold water and only moderately soluble in hot water and ethanol at 16 ° C.
From the xanthine nucleoside xanthosine and the nucleotide Xanthosinmonophosphat derived.
It is used together with 2,4- diaminopyrimidine for examining unusual base pairs in the DNA.
Pathophysiology
Xanthine stones are relatively rare. They can occur at a Xanthinuria. Cause of the not so rare Xanthinuria is a genetically determined defect of xanthine oxidase. Since medically xanthine is relatively soluble in water occur only in about 40 % of those affected urinary stones. A Xanthinuria may also occur with treatment with allopurinol. Allopurinol inhibits xanthine oxidase and is used as a medication to lower serum uric acid levels (mainly gout patients). Too little fluid intake in the urine can be a critical for stone formation xanthine concentration can be achieved.