H3R is becoming an attractive and promising target for epilepsy treatment as well as the discovery of antiepileptics. In this work, a series of 6-aminoalkoxy-3,4-dihydroquinolin-2(1H)-ones was prepared to screen their H3R antagonistic activities and antiseizure effects. The majority of the target compounds displayed a potent H3R antagonistic activity. Among them, compounds 2a, 2c, 2h, and 4a showed submicromolar H3R antagonistic activity with an IC50 of 0.52, 0.47, 0.12, and 0.37 μM, respectively. The maximal electroshock seizure (MES) model screened out three compounds (2h, 4a, and 4b) with antiseizure activity. Meanwhile, the pentylenetetrazole (PTZ)-induced seizure test gave a result that no compound can resist the seizures induced by PTZ. Additionally, the anti-MES action of compound 4a fully vanished when it was administrated combined with an H3R agonist (RAMH). These results showed that the antiseizure role of compound 4a might be achieved by antagonizing the H3R receptor. The molecular docking of 2h, 4a, and PIT with the H3R protein predicted their possible binding patterns and gave a presentation that 2h, 4a, and PIT had a similar binding model with H3R.
H3R正成为治疗癫痫和发现抗癫痫药物的一个具有吸引力和前景的靶点。本研究制备了一系列 6-氨基烷氧基-3,4-二氢喹啉-2(1H)-酮,以筛选其 H3R 拮抗活性和抗癫痫作用。大多数目标化合物显示出了强效的 H3R 拮抗活性。其中,化合物 2a、2c、2h 和 4a 显示出亚微摩级的 H3R 拮抗活性,IC50 分别为 0.52、0.47、0.12 和 0.37 μM。最大电击癫痫发作(MES)模型筛选出了三个具有抗癫痫活性的化合物(2h、4a 和 4b)。同时,戊四唑(PTZ)诱导的癫痫发作试验结果表明,没有化合物能抵抗 PTZ 诱导的癫痫发作。此外,当化合物 4a 与 H3R 激动剂(RAMH)联合使用时,其抗 MES 作用完全消失。这些结果表明,化合物 4a 的抗癫痫作用可能是通过拮抗 H3R 受体实现的。2h、4a和PIT与H3R蛋白的分子对接预测了它们可能的结合模式,结果表明2h、4a和PIT与H3R具有相似的结合模式。