Synthesis, characterization and DNA interactions of [Pt3(TPymT)Cl3], the trinuclear platinum(II) complex of the TPymT ligand

The triplatinum complex of the 2,4,6-Tris(2-pyrimidyl)-1,3,5-triazine ligand, Pt3TPymT hereafter, has been prepared and characterized for the first time. NMR studies point out that the three platinum(II) centers possess an identical coordination environment. The interactions of Pt3TPymT with DNA were explored in comparison to the free ligand. Specifically, fluorescence, mass spectrometry, viscometry and melting measurements were carried out. In contrast to expectations, the obtained data reveal that no intercalative binding takes place; we propose that binding of Pt3TPymT to DNA mainly occurs through external/groove binding.