2-Amido-3-(1H-Indol-3-yl)-N-Substitued-Propanamides as a New Class of Falcipain-2 Inhibitors. 1. Design, Synthesis, Biological Evaluation and Binding Model Studies
作者:Jin Zhu、Tong Chen、Lili Chen、Weiqiang Lu、Peng Che、Jin Huang、Honglin Li、Jian Li、Hualiang Jiang
DOI:10.3390/molecules14010494
日期:——
The Plasmodium falciparum cysteine protease falcipain-2 (FP-2) is an important cysteine protease and an essential hemoglobinase of erythrocytic P. falciparum trophozoites. The discovery of new FP-2 inhibitors is now a hot topic in the search for potential malaria treatments. In this study, a series of novel small molecule FP-2 inhibitors have been designed and synthesized based on three regional optimizations of the lead (R)-2-phenoxycarboxamido-3-(1H-indol-3-yl)-N-benzylpropanamide(1), which was identified using structure-based virtual screening in conjunction with surface plasmon resonance (SPR)-based binding assays. Four compounds – 1, 2b, 2k and 2l –showed moderate FP-2 inhibition activity, with IC50 values of 10.0-39.4 μM, and the inhibitory activityof compound 2k was ~3-fold better than that of the prototype compound 1 and may prove useful for the development of micromolar level FP-2 inhibitors. Preliminary SAR data was obtained, while molecular modeling revealed that introduction of H-bond donor or/and acceptor atoms to the phenyl ring moiety in the C region would be likely to produce some additional H-bond interactions, which should consequently enhance molecular bioactivity.
恶性疟原虫半胱氨酸蛋白酶恶性疟原虫滋养体-2(FP-2)是一种重要的半胱氨酸蛋白酶,也是红细胞恶性疟原虫滋养体的重要血红蛋白酶。发现新的 FP-2 抑制剂是目前寻找潜在疟疾治疗方法的热门话题。在本研究中,基于对先导物 (R)-2-phenoxycarboxamido-3-(1H-indol-3-yl)-N-benzylpropanamide(1) 的三次区域优化,设计并合成了一系列新型小分子 FP-2 抑制剂。1、2b、2k 和 2l 四种化合物显示出中等程度的 FP-2 抑制活性,IC50 值为 10.0-39.4 μM,其中化合物 2k 的抑制活性比原型化合物 1 的抑制活性高出约 3 倍,可能有助于开发微摩尔水平的 FP-2 抑制剂。研究获得了初步的 SAR 数据,而分子模型显示,在 C 区的苯环分子中引入 H 键供体或/和受体原子可能会产生一些额外的 H 键相互作用,从而提高分子的生物活性。