Photoluminescence and in vitro cytotoxicity of benzimidazole-based CuI/PtII complexes

Three novel complexes {Cu2(pzbmb)2(I)2}n (1), Pt(pzbmb)(Cl)2(DMSO) (2) and Pt(pdbmb)(Cl)2 (3) based on two novel V-shaped flexible ligands 1-((2-(pyrazinyl)-1H-benzoimidazol-1-yl)methyl)-1H-benzotriazole (pzbmb) and 1-((2-(pyridine-2-yl)-1H-benzoimidazol-1-yl)methyl)-1H-benzotriazole (pdbmb) have been synthesized under solvothermal conditions. Complex 1 possesses a 1D chain structure with short Cu⋯Cu distance being 3.008 Å, whereas complex 2 and 3 are mononuclear motifs. Complexes 1–3 exhibit strong phosphorescence at different temperatures in the range of 13–298 K, which is attributed to the presence of intersystem crossing from singlet to triplet caused by the heavy-atom effect. After being tested against SH-SY5Y (neuroblast tumor cell line) by standard MTT assay, complex 3 displayed promising cytotoxicity.

Graphical AbstractThe reactions of CuI/PtII metal centers and V-shaped flexible ligands bring about complexes 1–3 with different motifs. Complexes 1–3 exhibit strong phosphorescence and complex 3 has promisingly cytotoxicity.Figure optionsDownload full-size imageDownload as PowerPoint slide