Metal and structure tuned in vitro antitumor activity of benzimidazole-based copper and zinc complexes

Abstract

Four new complexes, Cu2(p-2-bmb)2Cl4 (1), Cu2(p-2-bmb)2Br4 (2), Zn2(p-3-bmb)2Cl4 (3), and [Cu3(p-3-bmb)2Cl4·(CH3OH)2] n (4), have been synthesized under solvothermal reactions based on V-shaped flexible ligands 1-((2-(pyridin-2-yl)-1H-benzoimidazol-1-yl)methyl)-1Hbenzotriazole (p-2-bmb) and 1-((2-(pyridin-3-yl)-1H-benzoimidazol-1-yl)methyl)-1Hbenzotriazole (p-3-bmb). Complexes 1–3 are binuclear, whereas 4 is an infinite chain with trimetallic units, and then these complexes are further extended into 3D supramolecular architectures by π…π interactions and hydrogen bonds. In vitro antitumor activities of these complexes on four human tumor cell lines (gastric tumor cell line, esophagus tumor cell line, liver tumor cell line, colon tumor cell line) were evaluated by MTT assay. The results exhibit that these complexes inhibit the growth of cancer cells by inducing apoptosis, and the inhibition effect shows time- and dose-effect relationship.