Department of Biological Sciences, Purdue University , 915 W. State Street, West Lafayette, Indiana 47907, United States.
J Med Chem. 2014 Mar 27;57(6):2393-412. doi: 10.1021/jm401712t. Epub 2014 Mar 14.
Structure-guided design was used to generate a series of noncovalent inhibitors with nanomolar potency against the papain-like protease (PLpro) from the SARS coronavirus (CoV). A number of inhibitors exhibit antiviral activity against SARS-CoV infected Vero E6 cells and broadened specificity toward the homologous PLP2 enzyme from the human coronavirus NL63. Selectivity and cytotoxicity studies established a more than 100-fold preference for the coronaviral enzyme over homologous human deubiquitinating enzymes (DUBs), and no significant cytotoxicity in Vero E6 and HEK293 cell lines is observed. X-ray structural analyses of inhibitor-bound crystal structures revealed subtle differences between binding modes of the initial benzodioxolane lead (15g) and the most potent analogues 3k and 3j, featuring a monofluoro substitution at para and meta positions of the benzyl ring, respectively. Finally, the less lipophilic bis(amide) 3e and methoxypyridine 5c exhibit significantly improved metabolic stability and are viable candidates for advancing to in vivo studies.
采用结构导向设计，生成了一系列针对 SARS 冠状病毒（CoV）木瓜样蛋白酶（PLpro）的具有纳摩尔效力的非共价抑制剂。许多抑制剂对感染 SARS-CoV 的 Vero E6 细胞表现出抗病毒活性，并对来自人冠状病毒 NL63 的同源 PLP2 酶具有更广泛的特异性。选择性和细胞毒性研究表明，冠状病毒酶对同源人去泛素化酶（DUB）的选择性超过 100 倍，并且在 Vero E6 和 HEK293 细胞系中没有观察到明显的细胞毒性。抑制剂结合晶体结构的 X 射线结构分析揭示了初始苯并二恶烷先导化合物（15g）和最有效的类似物 3k 和 3j 的结合模式之间的细微差异，它们分别在苄基环的对位和间位具有单氟取代。最后，疏水性较小的双（酰胺）3e 和甲氧基吡啶 5c 表现出显著改善的代谢稳定性，是推进体内研究的可行候选物。
