作者:Bernhard Wünsch、Torsten Schläger、Dirk Schepmann
DOI:10.1055/s-0031-1289607
日期:2011.12
The oxa-Pictet-Spengler reaction of 2-(1-phenylpyrazol-5-yl)ethanol required the weak acid pyridinium p-toluenesulfonate to provide pyrano[4,3-c]pyrazoles with additional functional groups in the side chain. These functional groups allow the introduction of various amino substituents into the side chain in position 4. In receptor binding studies the aminoethyl-substituted pyranopyrazoles revealed higher Ï1 receptor affinities and Ï1/Ï2 selectivities than the shorter aminomethyl homologues. The pyranopyrazole bearing the phenylpiperidine substituent (K i = 0.99 nM) represents the most potent and that bearing the piperidine substituent the most selective (Ï1/Ï2 = 180) Ï1 ligands of this series of compounds.
2-(1-苯基吡唑-5-基)乙醇的氧杂-Pictet-Spengler 反应需要对甲苯磺酸吡啶鎓弱酸来提供侧链中带有额外官能团的吡喃并[4,3-c]吡唑。有了这些官能团,就可以在侧链的第 4 位引入各种氨基取代基。在受体结合研究中,氨基乙基取代的吡喃并唑与较短的氨基甲基同系物相比,具有更高的Ï1受体亲和力和Ï1/Ï2选择性。带有苯基哌啶取代基(K i = 0.99 nM)的吡喃并吡唑是该系列化合物中最强效的配体,而带有哌啶取代基的吡喃并吡唑则是最具选择性(Ï1/Ï2 = 180)的Ï1 配体。