Design, synthesis and biological evaluation of a 4,6-di(aziridin-1-yl)-1,3,5-triazine-benzimidazole hybrid as a...

This study aimed to develop a novel aziridine-1,3,5-triazine derivative combining DNA-alkylating aziridine rings with a benzimidazole-containing fragment associated with PARP-related chemotypes.

The synthesis of target (4,6-di(aziridin-1-yl)-N-(2-(4-((2-methyl-1H-benzo[d]imidazol-1-yl)methyl)-1H-1,2,3-triazol-1-yl)ethyl)-1,3,5-triazin-2-amine (7) was achieved through a multi-step approach, involving the synthesis of 2-methyl-1-(prop-2-yn-1-yl)-1H-benzo[d]imidazole (3) and subsequent click chemistry reaction with N-(2-azidoethyl)-4,6-di(aziridin-1-yl)-1,3,5-triazin-2-amine (6). Protein modeling, docking and molecular dynamics were performed using the Schrödinger suite. Compound 7 was evaluated for cytotoxicity in vitro (HCT-116, U87, HeLa, A549 and ECV304 cell lines) by MTT assay, genotoxicity in HCT-116 cells by DNA-comet assay, and in vivo in A549 and HCT-116 xenografts in immunodeficient BALB/c Nude mice.

Docking/MD suggested a PARP-1 binding mode, with key interactions comparable to established inhibitors such as talazoparib and olaparib. In vitro cytotoxicity assays against HCT-116, U87, HeLa, and A549 cell lines revealed dose-dependent antiproliferative effects, with IC₅₀ values of 14.12, 33.52, 44.60, and 26.4 µM, respectively. In vitro genotoxicity assays showed that incubation of HCT-116 cell line with the compound 7 causes dose-dependent damage to DNA integrity. In vivo, compound 7 inhibited tumor growth in A549 xenografts (up to 75.1%, p < 0.05) and demonstrated dose-dependent activity in HCT-116 xenografts (up to 82.9% TGI at 6 mg/kg, i.v.).