Xanthine

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Xanthine
IUPAC name	3,7-Dihydro-purine-2,6-dione
Other names	1H-Purine-2,6-diol
Identifiers
CAS number	[69-89-6]
PubChem	1188
SMILES	C1=NC2=C(N1)C(=O)NC(=O)N2
Properties
Molecular formula	C5H4N4O2
Molar mass	152.111 g/mol
Appearance	White solid
Melting point	decomposes
Solubility in water	1 g/ 14.5 L @ 16 °C 1 g/1.4 L @ 100 °C
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Xanthine (IPA: [ˈzænθin]), (3,7-dihydro-purine-2,6-dione), is a purine base found in most body tissues and fluids and in other organisms. Xanthine is a product on the pathway of purine degradation and is converted to uric acid by the action of the xanthine oxidase enzyme. Some people lack sufficient xanthine oxidase, and thus xanthine cannot be converted to uric acid. This rare genetic disorder is called xanthinuria.

Derivatives of xanthine, known collectively as xanthines, are a group of alkaloids that are commonly used for their effects as mild stimulants and as bronchodilators, notably in treating the symptoms of asthma. On the contrary, they really only eliminate the actions of adenosine to some extent, adenosine causing sleepiness, thus they are by far less in effectiveness as stimulants than sympathomimetic amines. Their effects, however, are widespread and their therapeutic range is narrow, so they are not the drug of choice in asthma treatment. Theraputic level is 10-20 micrograms/mL blood. Signs of toxicity include tremor, nausea, nervousness, and tachycardia/arrhythmia.

Methylated xanthine derivatives include caffeine, paraxanthine, theophylline, and theobromine (found mainly in chocolate). These drugs inhibit phosphodiesterase and antagonise adenosine. Xanthines are also found very rarely as constituents of nucleic acids.

[edit] References

v • d • e Medications commonly used in asthma and COPD (primarily R03)
Anticholinergics	Ipratropium, Tiotropium
Short acting β2-agonists	Salbutamol, Terbutaline
Long acting β2-agonists (LABA)	Bambuterol, Clenbuterol, Fenoterol, Formoterol, Salmeterol
Corticosteroids	Beclometasone, Budesonide, Ciclesonide, Fluticasone
Leukotriene antagonists	Montelukast, Pranlukast, Zafirlukast
Xanthines	Aminophylline, Theobromine, Theophylline
Mast cell stabilizers	Cromoglicate, Nedocromil
Combination products	Budesonide/formoterol, Fluticasone/salmeterol, Ipratropium/salbutamol