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Updated: May 28, 2026
Amide Coupling Reaction for the Synthesis of Bispyridine-based Ligands and Their Complexation to Platinum as Dinuclear Anticancer Agents
Published on: May 28, 2014
Synthesis, X-ray structure and cytotoxic effect of nickel(II) complexes with pyrazole ligands
Marta Sobiesiak1, Ingo-Peter Lorenz, Peter Mayer
1Collegium Medicum in Bydgoszcz, Nicholaus Copernicus University in Torun, Faculty of Pharmacy, Department of Inorganic and Analytical Chemistry, 85-094 Bydgoszcz, Poland.
Abstract:
Here we present the synthesis of the new Ni(II) complexes with chelating ligands 1-benzothiazol-2-yl-3,5-dimethyl-1H-pyrazole (a), 5-(2-hydroxyphenyl)-3-methyl-1-(2-pyridylo)-1H-pyrazole-4-carboxylic acid methyl ester (b) and 1-benzothiazol-2-yl-5-(2-hydroxyphenyl)-3-methyl-1H-pyrazole-4-carboxylic acid methyl ester (c). These ligands a-c create solid complexes with Ni(II). The crystal and molecular structures of two complexes were determined by X-ray diffraction method. Thermal stability of two complexes with ligand c by TG/DTG and DSC methods were also shown. Cytotoxic activity of all the complexes against three tumour cell lines and to normal endothelial cells (HUVEC) was also estimated. Complexes with ligand c exhibited relatively high cytotoxic activity towards HL-60 and NALM-6 leukaemia cells and WM-115 melanoma cells. Cytotoxic effectiveness of one of these complexes against melanoma WM-115 cells was two times higher than that of cisplatin. The protonation constant log K=9.63 of ligand b corresponding to the phenol 2-hydroxy group has been determined in 10% (v/v) DMSO/water solution (25°C). The coordination modes (formation of two monomeric species: NiL and NiL(2)) in the complexes with Ni(II) are discussed for b on the basis of the potentiometric and UV/Vis data.
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