Pyrazolo[4,3-<i>e</i>]1,2,4-triazolo[1,5-<i>c</i>]pyrimidine Derivatives as Highly Potent and Selective Human A<sub>3</sub> Adenosine Receptor Antagonists: Influence of the Chain at the N<sup>8</sup> Pyrazole Nitrogen
作者:Pier Giovanni Baraldi、Barbara Cacciari、Romeo Romagnoli、Giampiero Spalluto、Stefano Moro、Karl-Norbert Klotz、Edward Leung、Katia Varani、Stefania Gessi、Stefania Merighi、Pier Andrea Borea
DOI:10.1021/jm001047y
日期:2000.12.1
IB-MECA was measured in membranes of CHO cells stably transfected with the human A(3) receptor. The new compounds are among the most potent and selective A(3) antagonists so far described. The derivatives with higher affinity at human A(3) adenosine receptors proved to be antagonists, in the cAMP assay, capable of inhibiting the effect of IB-MECA with IC(50) values in the nanomolar range, with a trend strictly
先前已经报道了以初步形式(Baraldi等人,J.Med.Chem.1999,42,4473-4478)作为高效和选择性的人A(3)腺苷受体拮抗剂的一系列吡唑并三唑并嘧啶类化合物。合成的化合物显示在亚纳摩尔范围内的A(3)腺苷受体亲和力和在人类A(1),A(2A),A(2B)和A(3)腺苷的放射性配体结合测定中评估的高水平选择性受体。特别是,分析了该链在N(8)吡唑氮上的作用。这项研究使我们能够鉴定出在N(8)吡唑具有甲基的衍生物与在N(5)位置具有4-甲氧基苯基氨基甲酰基部分的衍生物是在亲和力和选择性(hA)方面均具有最佳结合特性的化合物(3)= 0.2 nM,hA(1)/ hA(3)= 5485,hA(2A)/ hA(3)= 6950,hA(2B)/ hA(3)= 1305)。在特定功能模型中,所有化合物均被证明是完全拮抗剂,其中在稳定转染了人A(3)受体的CHO细胞膜中测量了IB-M