2,6-Bis(2,6-diethylphenyliminomethyl)pyridine coordination compounds with cobalt(II), nickel(II), copper(II), and zinc(II): synthesis, spectroscopic characterization, X-ray study and in vitro cytotoxicity

• Published in: Journal of inorganic biochemistry 2015-01, Vol.142, p.1-7
• Main Authors: Martinez-Bulit, Pablo, Garza-Ortíz, Ariadna, Mijangos, Edgar, Barrón-Sosa, Lidia, Sánchez-Bartéz, Francisco, Gracia-Mora, Isabel, Flores-Parra, Angelina, Contreras, Rosalinda, Reedijk, Jan, Barba-Behrens, Norah
• Format: Article
• Language: English
• Subjects: 2,6-bis(arylimino)pyridine derivatives; Antineoplastic Agents - chemical synthesis; Antineoplastic Agents - chemistry; Antineoplastic Agents - toxicity; Cell Line, Tumor; Cobalt - chemistry; Cobalt(II); Coordination Complexes - chemical synthesis; Coordination Complexes - chemistry; Coordination Complexes - toxicity; Copper - chemistry; Copper(II); Crystallography, X-Ray; Cytotoxicity; Heptacoordinated compounds; Humans; Ligands; Magnetic Resonance Spectroscopy; Models, Molecular; Nickel - chemistry; Pyridines - chemistry; Spectroscopy, Near-Infrared; X-Ray Diffraction; Zinc - chemistry; Zinc(II)
• ISSN: 0162-0134; 1873-3344
• DOI: 10.1016/j.jinorgbio.2014.09.007

Coordination compounds with cobalt(II), nickel(II), copper(II) and zinc(II) and the ligand 2,6-bis(2,6-diethylphenyliminomethyl)pyridine (L) were synthesized and fully characterized by IR and UV–Vis-NIR spectroscopy, elemental analysis, magnetic susceptibility and X-ray diffraction for two representative cases. These novel compounds were designed to study their activity as anti-proliferative drugs against different human cancer cell lines. The tridentate ligand forms heptacoordinated compounds from nitrate metallic salts, where the nitrate acts in a chelating form to complete the seven coordination positions. In vitro cell growth inhibition was measured for CoII, CuII and ZnII complexes, as well as for the free ligand. Upon coordination, the IC50 value of the transition-metal compounds is improved compared to the free ligand. The copper(II) and zinc(II) compounds are the most promising candidates for further in vitro and in vivo studies. The activity against colon and prostate cell lines merits further research, in views of the limited therapeutic options for such cancer types. Heptacoordinated CoII, NiII, CuII and ZnII; structural characterization. In vitro cytotoxicity (IC50). Synthesis, characterization and in vitro evaluation of antiproliferative activity is described for heptacoordinated CoII, NiII, CuII and ZnII complexes with the new ligand 2,6-bis(2,6-diethylphenyliminomethyl)pyridine. [Display omitted] •Cobalt(II), nickel(II), copper(II) and zinc(II) form heptacoordinated compounds.•Increased cytotoxicity and selectivity towards several cell lines was observed for CoII, CuII and ZnII complexes.•Crystals of cobalt(II) and zinc(II) compounds were fully characterized using X-ray diffraction.