Synthesis, characterization, structures and cytotoxic activity of palladium(II) and platinum(II) complexes containing bis(2-pyridylmethyl)amine and saccharinate

Abstract

New palladium(II) and platinum(II) complexes containing bis(2-pyridylmethyl)amine (bpma) and saccharinate (sac), [Pd(bpma)(sac)](sac)center dot 2H(2)O (1), [Pt(bpma)(sac)](sac)-2H(2)O (2), (Pd(bpma)CII(sac)center dot 2H(2)O (3) and [Pt(bpma)(sac)]Cl center dot 1 center dot 5H(2)O (4), were synthesized and characterized by elemental analysis, IR, NMR and TG-DTA. A single-crystal X-ray analysis of 3 and 4 proved a distorted square-planar geometry around the metal ions with one tridentate bpma ligand and one Cl or sac monoanion. The [Pd(bpma)Cl](+) ions in 3 form dimers by intermolecular N-H center dot center dot center dot Cl and Pd center dot center dot center dot Pd interactions. The cations reside in the centers of a hydrogen-bonded honeycomb network formed by the uncoordinated sac ions and the lattice water molecules, while the cations of 4 are connected by N-H center dot center dot center dot Cl and OW-H center dot center dot center dot O hydrogen bonds into one-dimensional chains. Cyclic planar tetrameric and trimeric water clusters were observed in 3 and 4, respectively. Cytotoxicity of 1-4 was tested against A549. C6 and CHO cells. Although 2 and 4 have no cytotoxicity, the best results were achieved for 1 and 3. In particular, the cyctotoxic activity of 3 is comparable to cisplatin.