209350-70-9Relevant academic research and scientific papers
1-Substituted 4-[chloropyrazolyl][1,2,4]triazolo[4,3-a]quinoxalines: Synthesis and structure-activity relationships of a new class of benzodiazepine and adenosine receptor ligands
Matuszczak, Barbara,Pekala, Elsbieta,Mueller, Christa E.
, p. 163 - 169 (1998)
Starting from 3-(3-chloro-1H-pyrazol-5-yl)-1H-quinoxalin-2-one (2) a series of substituted [1,2,4]triazolo[4,3-a]quinoxalines (3a-f) was prepared via a multistep reaction sequence. Affinities of the novel derivatives 3a-f for benzodiazepine as well as for adenosine A1- and A(2A)-receptors of rat brain were determined by radioligand binding assays. 1-Methyl-4-(3-chloro- 1H-pyrazol-5-yl) derivative 3a exhibited submicromolar affinity for the benzodiazepine binding site of GABA(A) receptors (K(i) = 340 nM) and was less potent at A1- (K(i) = 7.85 μM) and A(2A)-(K(i) = 1.43 μM) adenosine receptors (AR). Derivatives with larger substituents in the 1-position showed reduced binding to benzodiazepine and A(2A)-AR, but increased A1-AR affinity, the 2-thienylmethyl derivative 3f being the most potent and selective A1-AR ligand of the present series (K(i) = 200 nM).
