Borthwick A D, Angier S J, Crame A J, Exall A M, Haley T M, Hart G J, Mason A M, Pennell A M, Weingarten G G
Departments of Medicinal Chemistry 2, Molecular Cell Biology, Biomolecular Structure, and Enzyme Pharmacology, Glaxo Wellcome Research and Development, Medicines Research Centre, Stevenage Herts, U.K.
J Med Chem. 2000 Nov 16;43(23):4452-64. doi: 10.1021/jm000078q.
Mechanism-based inhibitors of human cytomegalovirus (HCMV) protease have been designed based on the pyrrolidine-5,5-trans-lactam ring system. New routes to the beta-methyl-, desmethyl-, and alpha-methyl-pyrrolidine-5,5-trans-lactam templates have been developed from 2,4-diaminobutyric acid. ESI/MS studies have shown that these inhibitors can bind covalently and reversibly to the viral enzyme in a time-dependent manner by a mechanism which is consistent with acylation of HCMV deltaAla protease at the active site nucleophile Ser 132. SAR in this series of pyrrolidine-5, 5-trans-lactams has defined the relative stereochemisty of the methyl substituent adjacent to the lactam carbonyl, the functionality on the lactam nitrogen, and the mechanism of action of this novel series of serine protease inhibitors against the HCMV deltaAla protease. Activity decreases on moving from the alpha-methyl to the desmethyl to the beta-methyl series. This selectivity is the opposite of that observed for these templates against the elastase and thrombin enzymes. The activity against HCMV deltaAla protease is the greatest with inhibitors based on the Cbz-protected alpha-methyl-5,5-trans-lactam template which have low micromolar activity against the viral enzyme.
基于吡咯烷-5,5-反式内酰胺环系统设计了人巨细胞病毒（HCMV）蛋白酶的基于机制的抑制剂。已从2,4-二氨基丁酸开发出通往β-甲基、去甲基和α-甲基吡咯烷-5,5-反式内酰胺模板的新路线。电喷雾电离质谱（ESI/MS）研究表明，这些抑制剂可通过与HCMV δAla蛋白酶活性位点亲核试剂丝氨酸132发生酰化作用的机制，以时间依赖性方式与病毒酶共价且可逆地结合。这一系列吡咯烷-5,5-反式内酰胺的构效关系（SAR）已确定了内酰胺羰基相邻甲基取代基的相对立体化学、内酰胺氮上的官能团以及这一系列新型丝氨酸蛋白酶抑制剂针对HCMV δAla蛋白酶的作用机制。从α-甲基系列到去甲基系列再到β-甲基系列，活性降低。这种选择性与这些模板对弹性蛋白酶和凝血酶的选择性相反。基于Cbz保护的α-甲基-5,5-反式内酰胺模板的抑制剂对HCMV δAla蛋白酶的活性最高，对病毒酶具有低微摩尔活性。
