As members of the MAPK family, c-Jun-N-terminal kinases (JNKs) regulate the biological processes of apoptosis. In particular, the isoform JNK3 is expressed explicitly in the brain at high levels and is involved in the pathogenesis of neurodegenerative diseases such as Alzheimer’s disease (AD) and Parkinson’s disease (PD). In this study, we prepared a series of five 6-dihydroxy-1H-benzo[d]imidazoles as JNK3 inhibitors and found them have potential as neuroprotective agents. Following a previous lead scaffold, benzimidazole moiety was modified with various aryl groups and hydroxylation, and the resulting compounds exhibited JNK3 inhibitory activity with improved potency and selectivity. Out of 37 analogues synthesized, (S)-cyclopropyl(3-((4-(2-(2,3-dihydrobenzo[b][1,4]dioxin -6-yl)-5,6-dihydroxy-1H-benzo[d]imidazol-1-yl)pyrimidin-2-yl)amino) piperidin-1-yl)methanone (35b) demonstrated the highest JNK3 inhibition (IC50 = 9.7 nM), as well as neuroprotective effects against Aβ-induced neuronal cell death. As a protein kinase inhibitor, it also showed excellent selectivity over other protein kinases including isoforms JNK1 (>1000 fold) and JNK2 (−10 fold).
作为
MAPK家族的成员,c-Jun-N末端激酶(JNKs)调节细胞凋亡的
生物过程。特别是,JNK3亚型在大脑中以高
水平明确表达,并参与神经退行性疾病如阿尔茨海默病(AD)和帕
金森病(PD)的发病机制。在这项研究中,我们制备了一系列五种6-二羟基-1H-苯并[d]
咪唑作为JNK3
抑制剂,发现它们具有作为神经保护剂的潜力。在之前的引物骨架基础上,
苯并咪唑基团经过各种芳基和羟基修饰,得到的化合物表现出改进的JNK3抑制活性和选择性。在合成的37个类似物中,(S)-环丙基(3-((4-(2-(2,3-二氢苯并[b][1,4]二氧杂环己-6-基)-5,6-二羟基-1H-苯并[d]
咪唑-1-基)
嘧啶-2-基)
氨基)
哌啶-1-基)甲酮(35b)表现出最高的JNK3抑制作用(IC50 = 9.7 nM),以及对Aβ诱导的神经元
细胞死亡的神经保护作用。作为蛋白激酶
抑制剂,它还显示出对其他蛋白激酶,包括JNK1(>1000倍)和JNK2(-10倍)亚型的优异选择性。