Synthesis, characterization, and cytotoxicity of mixed-ligand complexes of platinum(II) with 2,2′-bipyridine and 4-toluenesulfonyl-L-amino acid dianion

Abstract

Five new platinum(II) complexes (1–5) with 4-toluenesulfonyl-L-amino acid dianion and 2,2′-bipyridine (bipy) have been synthesized and characterized by elemental analysis, IR, UV, ¹H-NMR, ¹³C-NMR, and mass spectra. The crystal structure of 1 has been determined by X-ray diffraction analysis. Cytotoxicity was tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and sulforhodamine B (SRB) assays. The results indicate that 1–5 exert cytotoxic effects with selectivity against tested carcinoma cell lines; 5 displays better cytotoxicity against BGC-823, Bel-7402, and KB cell lines, while 1 has better cytotoxicity against KB cell line. The 4-toluenesulfonyl- L-amino acid dianions have important effects on cytotoxicity; when 4-toluenesulfonyl-L-amino acid dianions are 4-toluenesulfonyl-L-glycine and 4-toluenesulfonyl-L-phenylalanine, the complexes show better cytotoxicity.

Keywords:

• Platinum(II) complexes
• Synthesis
• Characterization
• Cytotoxicity

Acknowledgments

This study was supported by the Special Foundation for State Major New Drug Research Program of China (grant no. 2009ZX09103-139), the National Basic Research 973 Program (grant no. 2010CB534913), Hebei Province Nature Science Fund for Distinguished Young Scholars (grant no. B2011201164), the Nature Science Fund of Hebei Province (grant no. B2011201135), and Key Research Project Foundation of Department of Education of Hebei Province (grant no. ZD2010142).