Synthesis, ligand–receptor modeling studies and pharmacological evaluation of novel 4-modified-2-aryl-1,2,4-triazolo[4,3-a]quinoxalin-1-one derivatives as potent and selective human A3 adenosine receptor antagonists
作者:Vittoria Colotta、Daniela Catarzi、Flavia Varano、Ombretta Lenzi、Guido Filacchioni、Claudia Martini、Letizia Trincavelli、Osele Ciampi、Chiara Traini、Anna Maria Pugliese、Felicita Pedata、Erika Morizzo、Stefano Moro
DOI:10.1016/j.bmc.2008.04.039
日期:2008.6
The study of some 4-substituted-2-aryl-1,2,4-triazolo[4,3-a]quinoxalin-1-one derivatives, designed as hA(3) adenosine receptor antagonists, is reported. The new compounds bear on the four-position different acylamino, sulfonylamino, benzylureido and benzyloxy moieties, which have also been combined with a para-methoxy group on the 2-phenyl ring or with a nitro residue at the six-position. Many derivatives show high hA(3) adenosine receptor affinities and selectivities both versus hA(1) and hA(2A) receptors. The observed structure-affinity relationships of this class of antagonists have been exhaustively rationalized using the recently published ligand-based homology modeling (LBHM) approach. The selected 4-bismethanesulfonylamino-2-phenyl-1,2,4-triazolo[4,3a]quinoxalin-1-one (13), which shows high hA(3) affinity (K-i = 5.5 nM) and selectivity versus hA(1), hA(2A) (both selectivity ratios > 1800) and hA(2B) (cAMP assay, IC50 > 10,000 nM) receptors, was tested in an in vitro rat model of cerebral ischemia, proving to be effective in preventing the failure of synaptic activity, induced by oxygen and glucose deprivation in the hippocampus, and in delaying the occurrence of anoxic depolarization. (C) 2008 Elsevier Ltd. All rights reserved.