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. Their effects, however, are widespread and their therapeutic range is narrow and so they are not the drug of choice in asthma treatment.

Methylated xanthine derivatives include caffeine, theophylline, and theobromine (found mainly in chocolate). These drugs inhibit phosphodiesterase and antagonise adenosine.

The core compound, 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.

Xanthines are purine derivatives and found very rarely in constituents of nucleic acids.

Xanthines

Xanthin | Xanthin | Metilxantina | Xanthine | 黄嘌呤