New 2-Piperazinylbenzimidazole Derivatives as 5-HT<sub>3</sub> Antagonists. Synthesis and Pharmacological Evaluation
作者:Aurelio Orjales、Ramón Mosquera、Luis Labeaga、Rosa Rodes
DOI:10.1021/jm960442e
日期:1997.2.1
of 2-piperazinylbenzimidazole derivatives were prepared and evaluated as 5-HT3 receptor antagonists. Their 5-HT3 receptor affinities were evaluated by radioligand binding assays, and their abilities to inhibit the 5-HT-induced Bezold-Jarisch reflex in anesthetized rats were determined. Compound 7e (lerisetron, pKi = 9.2) exhibited higher affinity for the 5-HT3 receptor than did tropisetron and granisetron
制备了一系列2-哌嗪基苯并咪唑衍生物,并将其评价为5-HT 3受体拮抗剂。通过放射性配体结合测定法评估了它们的5-HT3受体亲和力,并确定了它们在麻醉大鼠中抑制5-HT诱导的Bezold-Jarisch反射的能力。化合物7e(lerisetron,pKi = 9.2)对5-HT3受体的亲和力高于tropisetron和granisetron,而化合物7q(pKi = 7.5)对该受体的亲和力很低,表明苯并咪唑的N1原子被取代环对于亲和力和活性至关重要。还讨论了不同位置的多个取代基对苯并咪唑芳环的取代作用。建立了所研究化合物的5-HT3拮抗活性与芳香环上取代位置的强相关性。因此,尽管4-甲氧基衍生物7m显示出对5-HT 3受体的弱亲和力(pKi = 6.7),但是7-甲氧基衍生物7n显示出最高的亲和力(pKi = 9.4)。化合物7e和7n作为癌症化疗和放疗引起的恶心和呕吐的治疗药物,目前正在进一步研究中。