Tricyclic heteroaromatic systems. Synthesis and benzodiazepine receptor affinity of 2-substituted-1-benzopyrano [3,4-d] oxazol-4-ones, -thiazol-4- ones, and -imidazol-4-ones

Article abstract of DOI:10.1016/S0014-827X(98)00028-7

A number of 2-aryl-substituted-1-benzopyrano [3,4-d] oxazol-4-ones 1, - thiazol-4-ones 2 and -imidazol-4-ones 3 were synthesized. Benzodiazepine receptor (BZR) binding assays were performed on these series of tricyclic heteroaromatic systems. None of the tested compounds showed detectable affinity for BZR. Comparative structure-activity relationship analysis between the reported compounds and some known BZR ligands of similar size and shape revealed that, according to a two-dimensional schematic representation of the interaction of these kinds of tricyclic heteroaromatic systems with the BZR recognition site, the nature of the optional a~ proton acceptor is of significant importance in the receptor-ligand interaction.