Discovery of 1H-benzo[d]imidazole-(halogenated) Benzylidenebenzohydrazide Hybrids as Potential Multi-Kinase Inhibitors

Abstract

In an effort to develop improved and effective targeted tyrosine kinase inhibitors (TKIs), a series of twelve novel compounds with the structural motif “(E)-4-(((1H-benzo[d]imidazol-2-yl)methyl)amino)-N′-(halogenated)benzylidenebenzohydrazide” were successfully synthesized in three steps, yielding high product yields (53–97%). Among this new class of compounds, 6c and 6h-j exhibited excellent cytotoxic effects against four different cancer cell lines, with half-maximal inhibitory concentration (IC50) values ranging from 7.82 to 21.48 μM. Notably, compounds 6h and 6i emerged as the most potent inhibitors, demonstrating significant activity against key kinases such as EGFR, HER2, and CDK2. Furthermore, compound 6h displayed potent inhibitory activity against AURKC, while 6i showed potent inhibitory effects against the mTOR enzyme, with excellent IC50 values comparable with well-established TKIs. The mechanistic study of lead compound 6i revealed its ability to induce cell cycle arrest and apoptosis in HepG2 liver cancer cells. This was accompanied by upregulation of pro-apoptotic caspase-3 and Bax and downregulation of anti-apoptotic Bcl-2. Additionally, molecular docking studies indicated that the binding interactions of compounds 6h and 6i with the target enzymes give multiple interactions. These results underscore the ability of compound 6i as a compelling lead candidate warranting further optimization and development as a potent multi-targeted kinase inhibitor, which could have significant implications for the treatment of various cancers. The detailed structural optimization, mechanism of action, and in vivo evaluation of this class of compounds warrant further investigation to assess their therapeutic potential.