Development of Potent Serotonin-3 (5-HT3) Receptor Antagonists. I. Structure-Activity Relationships of 2-Alkoxy-4-amino-5-chlorobenzamide Derivatives.
作者:Hiroshi HARADA、Toshiya MORIE、Yoshimi HIROKAWA、Naoyuki YOSHIDA、Shiro KATO
DOI:10.1248/cpb.43.1364
日期:——
A new series of 2-alkoxy-4-amino-5-chlorobenzamide derivatives bearing five- to seven-membered heteroalicyclic rings in the amine moiety was synthesized and evaluated for serotonin-3 (5-HT3) receptor antagonistic activity by assaying the ability to antagonize the von Bezold-Jarisch reflex in rats. The five- to seven-membered heteroalicycles comprise pyrrolidine, morpholine, 1, 4-thiazine, piperidine, piperazine, 1, 4-oxazepine, 1, 4-thiazepine, azepine, and 1, 4-diazepine rings. Among them, some benzamide derivatives having a 1, 4-diazepine ring showed a potent 5-HT3 receptor antagonistic activity. In particular, 4-amino-5-chloro-N-(1, 4-dimethylhexahydro-1H-1, 4-diazepin-6-yl)-2-ethoxybenzamide (96) and the 1-benzyl-4-methylhexahydro-1H-1, 4-diazepine analogue 103 showed potent 5-HT3 receptor antagonistic activity without 5-HT4 receptor binding affinity.
合成了一系列新的2-烷氧基-4-氨基-5-氯苯甲酰胺衍生物,这些衍生物在氨基部分包含五到七元的杂环非芳香环,并通过测试其对大鼠冯·贝佐尔德-雅里希反射的拮抗能力来评估其对血清素-3(5-HT3)受体的拮抗活性。五到七元的杂环包括吡咯烷、吗啉、1,4-噻嗪、哌啶、哌嗪、1,4-噁唑烯、1,4-噻唑烯、七元环及1,4-二唑烯环。其中,某些具有1,4-二唑烯环的苯甲酰胺衍生物表现出了强效的5-HT3受体拮抗活性。特别是4-氨基-5-氯-N-(1,4-二甲基六氢-1H-1,4-二唑啉-6-基)-2-乙氧基苯甲酰胺(96)和1-苄基-4-甲基六氢-1H-1,4-二唑啉类似物103展现了强效的5-HT3受体拮抗活性,而未表现出对5-HT4受体的结合亲和力。