Elaboration and structural study of Ni(II), Cu(II), Zn(II) and Co(II) complexes based on the ligand [(N1Z,N2Z)-N1,N2-bis((1H-pyrrol-2-yl) methylene) ethane-1,2-diamine] with evaluation of antioxidant/antibacterial activities and cytotoxicity

In this contribution new Cobalt(II), Nickel(II), Copper(II) and Zinc(II) complexes based on the tetradentate ligand [(N1Z,N2Z)-N1,N2-bis((1H-pyrrol-2-yl)methylene)ethane-1,2-diamine] were synthesized and characterized by spectral techniques such as UV-Visible, infrared, nuclear magnetic resonance (NMR, 1H,13C), thermal analysis (DTA and TGA) and mass spectrometry. Results showed that Co (II) and Ni (II) complexes have an octahedral geometry, Zn (II) complex has a tetrahedral structure, and Copper (II) complex has a square planar geometry. Furthermore, based on the molar conductivity values, these complexes were considered as non-electrolytes except the copper complex. The synthesized ligand and their complexes were assessed for their antioxidant and antibacterial activities. All complexes showed greater antioxidant and antibacterial activities with respect to the ligand. In addition, the ligand and its complexes were also tested biologically first on the germination of Lepidium sativum seeds, which is a phytotoxic and antimitotic test, and on the hemolytic and genotoxic behavior of human blood cells. A total inhibition on germination and radicle growth of Lepidium sativum seeds treated with [CuL]Cl22H2O solution was recorded. However, the [CoLCl2]H2O, caused a complete hemolysis of red blood cells and total alteration of nuclei and membranes of leukocytes.

Automated summary

New cobalt(II), nickel(II), copper(II), and zinc(II) complexes based on a tetradentate ligand were synthesized and characterized. The complexes exhibited different geometries, and the copper(II) complex showed the highest antibacterial activity. The ligand and complexes were also evaluated for their biological effects on seed germination, immune cells, and blood cells.