Synthesis, characterization and cytotoxicity of mixed-ligand complexes of palladium(II) with 2, 2′-biquinoline/1, 4-diaminobutane and 4-toluenesulfonyl-L-amino acid dianion

Seven new palladium(II) complexes (1–7) with 4-toluenesulfonyl-L-amino acid dianion and 2, 2′-biquinoline (bqu)/1,4-diaminobutane (dab) have been synthesized and characterized by elemental analysis, IR, 1H NMR, and mass spectra techniques. Crystal structure of the complex (7) has been determined by X-ray diffraction analysis. The cytotoxicity was tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and sulforhodamine B (SRB) assays. The results indicate that the complexes exert cytotoxic effects with selectivity against tested carcinoma cell lines, but their cytotoxicity is less than that of cisplatin. It suggests that all the amino acids, N-containing ligands and metal ions have important effect on cytotoxicity, but the IC50 values do not show definite correlation with variation of amino acids, N-containing ligands and metal ions, the cytotoxicity of complexes is related to tumor cell species. Seven new palladium(II) complexes have been synthesized. Crystal structure of complex 7 has been determined by X-ray diffraction analysis. The cytotoxicity was tested by MTT and SRB assays. [Display omitted] ▸ Seven palladium(II) complexes have been synthesized. ▸ Crystal structure of the complex 7 has been determined. ▸ The most complexes exert cytotoxic effects with selectivity. ▸ Amino acids, N-containing ligands and metal ions have important effect on cytotoxicity.