Pharmacological and toxicological activities of a new methylxanthine derivative [7-(1,3-dithiolan-2-ylmethyl)1,3-dimethylxanthine] with antibronchospastic and mucoregulatory properties.

7-(1,3-Dithiolan-2-ylmethyl)-1,3-dimethylxanthine (ABC 99) has been studied in the animal to evaluate its pharmacological activity. This compound was found to have antibronchospastic activity in vitro and in vivo markedly greater than aminophylline. The new compound also had moderate antitussic properties and was an active mucoregulator. ABC 99 acts as an intestinal muscle relaxant, but it has no cardiovascular, urinary, or CNS side effects. The mechanism of ABC 99 could be explained by its inhibition of guinea-pig lung phosphodiesterases and affinity for adenosine receptors, particularly A2 receptors. ABC 99 had a low acute toxicity in animals, indicating it may be useful for treating asthma and chronic bronchitis.