Benzimidazole Derivatives as New Serotonin 5-HT6 Receptor Antagonists. Molecular Mechanisms of Receptor Inactivation
摘要:
On the basis of our previously described pharmacophore model for serotonin 5-HT6 receptor (5-HT6R) antagonists, we have designed, synthesized, and pharmacologically characterized a series of benzimidazole derivatives 1-20 that represent a new family of potent antagonists at the human 5-HT6R. Site-directed mutagenesis and a beta(2)-adrenoceptor-based homology model of the 5-HT6R were used to predict the mode of binding of antagonist SB-258585 and the new synthesized ligands. Substitution of W6.48, F6.52, or N6.55 by Ala fully impedes compound 4 to block 5-HT-induced activation. Thus, we propose that D3.32 in TM 3 anchors the protonated piperazine ring, the benzimidazole, ring expands parallel to EL 2 to hydrogen bond N6.55 in TM 6, and the aromatic ring is placed between TMs 3 and 5 in CH2-containing compounds and between TMs 3 and 6 in CO-containing compounds. This combined experimental and computational study has permitted to propose the molecular mechanisms by which the new benzimidazole derivatives act as 5-HT6R antagonists.
Benzimidazole Derivatives as New Serotonin 5-HT<sub>6</sub> Receptor Antagonists. Molecular Mechanisms of Receptor Inactivation
作者:Tania de la Fuente、Mar Martín-Fontecha、Jessica Sallander、Bellinda Benhamú、Mercedes Campillo、Rocío A. Medina、Lucie P. Pellissier、Sylvie Claeysen、Aline Dumuis、Leonardo Pardo、María L. López-Rodríguez
DOI:10.1021/jm901672k
日期:2010.2.11
On the basis of our previously described pharmacophore model for serotonin 5-HT6 receptor (5-HT6R) antagonists, we have designed, synthesized, and pharmacologically characterized a series of benzimidazole derivatives 1-20 that represent a new family of potent antagonists at the human 5-HT6R. Site-directed mutagenesis and a beta(2)-adrenoceptor-based homology model of the 5-HT6R were used to predict the mode of binding of antagonist SB-258585 and the new synthesized ligands. Substitution of W6.48, F6.52, or N6.55 by Ala fully impedes compound 4 to block 5-HT-induced activation. Thus, we propose that D3.32 in TM 3 anchors the protonated piperazine ring, the benzimidazole, ring expands parallel to EL 2 to hydrogen bond N6.55 in TM 6, and the aromatic ring is placed between TMs 3 and 5 in CH2-containing compounds and between TMs 3 and 6 in CO-containing compounds. This combined experimental and computational study has permitted to propose the molecular mechanisms by which the new benzimidazole derivatives act as 5-HT6R antagonists.