A New 1D Ni (II) Coordination Polymer of s-Triazine Type Ligand and Thiocyanate as Linker via Unexpected Hydrolysis of 2,4-Bis(3,5-dimethyl-1H-pyrazol-1-yl)-6-methoxy-1,3,5-triazine

Abstract

A new 1D Ni(II) coordination polymer was synthesized by the reaction of NiSO4·6H2O with 2,4-bis(3,5-dimethyl-1H-pyrazol-1-yl)-6-methoxy-1,3,5-triazine (BPT) and SCN− as a linker in an acidic medium by heating under reflux conditions. Unusually, the BPT ligand underwent acid-mediated hydrolysis by losing one of the pyrazolyl arms afforded the polymeric [Ni(MPT)(H2O)(SCN)2]n complex (MPT: 4-(3,5-dimethyl-1H-pyrazol-1-yl)-6-methoxy-1,3,5-triazin-2-ol. The Ni(II) center is coordinated with one MPT as a bidentate NN-chelate, one water molecule, and two thiocyanate groups in cis positions to one another. One of the thiocyanate groups acts as a bridging ligand between metal centers, leading to a one-dimensional polymeric structure that extends along the c-direction. The other thiocyanate group is terminally N-coordinated. The [Ni(MPT)(H2O)(SCN)2]n complex has been screened in vitro against two pathogenic fungal strains: A. fumigatus, C. albican, and four pathogenic bacterial strains: S. aureus, B. subtilis as gram-positive bacteria, E. coli, P. vulgaris as gram-negative bacteria. The results showed that the complex has the potential to be used as both an antibacterial and an antifungal agent. Also, the [Ni(MPT)(H2O)(SCN)2]n complex showed cytotoxic activities against hepatocellular (HepG-2) and lung (A-549) cell lines, with IC50 values of 132.67 ± 5.14 and 146.97 ± 7.34 μM, respectively.