Synthesis, Structure−Activity Relationships at the GABAA Receptor in Rat Brain, and Differential Electrophysiological Profile at the Recombinant Human GABAA Receptor of a Series of Substituted 1,2-Diphenylimidazoles
摘要:
A series of new 1,2-diphenylimidazole derivatives (la-x) were synthesized and evaluated for their ability to potentiate gamma-aminobutyric acid (GABA)-evoked currents in Xenopus laevis oocytes expressing recombinant human GABAA receptors. Many of these compounds enhanced GABA action with potencies (EC50 = 0.19-19,mu M) and efficacies (maximal efficacies of up to 640%) similar to or greater than those of anesthetics such as etomidate, propofol, and alphaxalone. Structure- activity relationship analysis revealed that the presence of an ester moiety in the imidazole ring was required for full agonist properties, while modifications made in the phenyl rings affected potency and efficacy, with ethyl 2-(4-bromophenyl)-l-(2,4-dichlorophenyl)-1H4-imidazolecarboxylate showing the highest potency. These compounds potentiated the [H-3]GABA binding to rat brain membranes, suggesting a site of interaction different from that of GABA. As for etomidate, mutation of asparagine-265 in the beta 2 subunit of the GABA(A) receptor into serine reduced the ability of derivative 1i to modulate the GABA function.
2-Aminopyrimidine-4,6-diol as an Efficient Ligand for Solvent-Free Copper-Catalyzed N-Arylations of Imidazoles with Aryl and Heteroaryl Halides
作者:Ye-Xiang Xie、Shao-Feng Pi、Jian Wang、Du-Lin Yin、Jin-Heng Li
DOI:10.1021/jo061572q
日期:2006.10.1
Efficient and solvent-free copper-catalyzed N-arylations of imidazoles with aryl and heteroaryl halides have been demonstrated. In the presence of CuBr, 2-aminopyrimidine-4,6-diol, and TBAF (n-Bu4NF), a variety of imidazoles underwent the N-arylation reaction with aryl and heteroaryl halides smoothly in moderate to excellent yields. Noteworthy is that the reaction is conducted under solvent-free conditions
N-Arylations of Nitrogen-Containing Heterocycles with Aryl and Heteroaryl Halides Using a Copper(I) Oxide Nanoparticle/1,10-Phenanthroline Catalytic System
and indoles, with aryl and heteroarylhalides catalyzed by copper(I) oxide (Cu 2 O) nanoparticles is demonstrated. Four types of Cu 2 O were evaluated: the bulky compound and its cubic, octahedral, and spherical nanoparticulate forms. The results show that Cu 2 O nanoparticles, in particular the cubic form, are highly efficient for the N-arylation reaction. In the presence of cubic Cu 2 O nanoparticles
演示了含氮杂环(即咪唑、三唑和吲哚)的无溶剂 N-芳基化的一般程序,其中芳基和杂芳基卤化物由氧化铜 (I) (Cu 2 O) 纳米颗粒催化。评估了四种类型的 Cu 2 O:大体积化合物及其立方、八面体和球形纳米颗粒形式。结果表明,Cu 2 O 纳米颗粒,特别是立方形式,对 N-芳基化反应非常有效。在立方 Cu 2 O 纳米粒子、1,10-菲咯啉和四丁基氟化铵存在下,多种含氮杂环在 110-145 °C 下与芳基和杂芳基卤化物顺利进行 N-芳基化反应,得到相应的产物以优异的产量。值得注意的是,该反应是在无溶剂条件下进行的。