Triazoloquinazolinediones as novel high affinity ligands for the benzodiazepine site of GABAA receptors
作者:Jakob Nilsson、Ritha Gidlöf、Elsebet Østergaard Nielsen、Tommy Liljefors、Mogens Nielsen、Olov Sterner
DOI:10.1016/j.bmc.2010.11.050
日期:2011.1
Based on a pharmacophore model of the benzodiazepine-binding site of GABA(A) receptors, a series of 2-aryl-2,6-dihydro[1,2,4]triazolo[4,3-c]quinazoline-3,5-diones (structure type I) were designed, synthesized, and identified as high-affinity ligands of the binding site. For several compounds, K-i values of around 0.20 nM were determined. They show a structural resemblance with the previously described 2-phenyl-2H-pyrazolo[4,3-c]quinolin-3(5H)-ones (II) and 2-phenyl-[1,2,4]triazolo[1,5-a]quinoxalin-4(5H)-one (III). The 9-bromo substituted compounds 8a-d were prepared in an 8-step synthesis in an overall yield of approximately 40%, and a library of 9-substituted analogues was prepared by cross-coupling reactions. Compound 8e, 21, 22, and 24 were tested on recombinant rat alpha(1)beta(3)gamma(2), alpha(2)beta(3)gamma(2), alpha(3)beta(3)gamma(2), and alpha(5)beta(3)gamma(2) subtypes, and displayed selectivity for the alpha(1)beta(3)gamma(2) isoform. (C) 2010 Elsevier Ltd. All rights reserved.