Substituted 1,2,3-triazolo[1,5-a]quinazolines: synthesis and binding to benzodiazepine and adenosine receptors

This paper reports the synthesis and evaluation of the biological affinity towards benzodiazepine and A(1) and A(2A) adenosine receptors of some 3-eth oxycarbonyl or 3-phenyl-substituted 1,2,3-triazolo[1,5-a]quinazolines. Star ting from the appropriate chloro-substituted phenylazides, the series of 7 or 8 chloro-substituted triazoloquinazolines were prepared. Nitration react ions of the triazoloquinazoline ring and chlorination reactions of the hydr oxyl group in the 5 position of the same ring are also reported. By nucleop hilic displacement of halogen, the corresponding 5-amino derivatives and so me analogous derivatives bearing cyclohexylamino and p-toluidino substituen ts were obtained. The binding assays showed a generalized decrease in the a ffinity towards the benzodiazepine receptors and confirmed a moderate affin ity towards the A, adenosine receptors in comparison with the previously st udied triazoloquinazoline derivatives. (C) 2000 Editions scientifiques et m edicales Elsevier SAS.