A New 5-HT3 Receptor Ligand. II. Structure-Activity Analysis of 5-HT3 Receptor Agonist Action in the Gut.
作者:Megumi YAMADA、Yasuo SATO、Kazuko KOBAYASHI、Fukio KONNO、Tomoko SONEDA、Takashi WATANABE
DOI:10.1248/cpb.46.445
日期:——
Several modified 2-piperazinyl benzoxazole derivatives, which exhibit an agonistic effect on gastrointestinal motility, were synthesized and their effects on the contraction of guinea-pig ileum were examined. The quaternary piperazinyl benzoxazole structure has a restricted conformation and stereostructure compared to those of the other 5-HT3 receptor agonists, serotonin and meta-chlorophenylbiguanide. The mutual positions of the aromatic ring, nitrogen atom and terminal amine are considered to form the pharmacophore of the 5-HT3 receptor agonist in the gut. In the serotonin-evoked reflex bradycardia [Bezold-Jarisch (B-J) reflex] inhibition test using rats the B-J reflex-inducing ratio was different for each synthesized compound. These results suggest that, in these 5-HT3 receptor agonists, the substituents of the benzoxazole ring influence the B-J reflex-inducing activity in rats.
合成了几种对胃肠道蠕动具有兴奋作用的2-哌嗪基苯并噁唑衍生物,并研究了它们对豚鼠回肠收缩的影响。与5-HT3受体激动剂5-羟色胺和邻氯苯基双胍相比,季铵哌嗪基苯并噁唑结构具有受限的构象和立体结构。苯环、氮原子和末端胺的相对位置被认为是形成肠道5-HT3受体激动剂的药效团。在用大鼠进行的阻断血清素诱发反射性心动过缓[Bezold-Jarisch(B-J)反射]的试验中,每个合成化合物的诱发B-J反射的比例是不同的。这些结果表明,在这些5-HT3受体激动剂中,苯并噁唑环的取代基会影响大鼠的诱发B-J反射活性。