Zinc, copper and nickel complexes of a macrocycle synthesized from pyridinedicarboxylic acid: A spectroscopic, thermal and theoretical study

Abstract

The metal(II) ion complexes of a pentadentate macrocycle 1, namely 3,12-dioxa-6,9,18-triazabicyclo[12.3.1]octadeca-1(18),14,16-triene-2,13-dione are synthesized. This macrocycle is prepared from the reaction of dipotassium salt of 2,6-pyridinedicarboxylic acid with ethylenediamine and 1,2-dibromoethane. The reaction of 1 (L) in methanol with MCl 2 .xH 2 O gave complexes with the general formula [M(L)Cl 2 ] (where M= Ni(II) 2, Cu(II) 3 and Zn(II) 4, respectively). The analysis of IR, 1 Hand 13 C-NMR spectral data of all complexes propose that 1 is bonded to metal(II) ions through a nitrogen atom of pyridine ring, two nitrogen atoms of amine groups and two oxygen atoms of ester moieties. The thermal analysis indicated that there are no water molecules of hydration or coordinated in the structure of the complexes. Among these complexes, the Cu(II) 3 complex demonstrated good antibacterial and antifungal activities. The molecular geometry, AIM atomic charge and frontier molecular orbitals of the compounds are investigated theoretically using DFT method. Based on the theoretical data of these complexes represented, a bipyramidal pentagonal arrangement can be envisaged in such a way that the N 3 O 2 pentadentate donor sites form the planar pentagonal base of the bipyramid and the two Cl atoms occupy the vertexes.

A binary copper(II) complex having stepped polymeric structure: Synthesis, characterization, DNA-binding and anti-fungal studies

“…Thus, the DNA-binding activity is a preliminary test along with antimicrobial activity after synthesis and characterization of a metal-based complex destined for biological activities. 8 In the present study, a copper(II) complex related to the less commonly found polymeric type of paddlewheel ________________________________________________________________________________________________________________________ Available on line at www.shd.org.rs/JSCS/ (CC) 2020 SCS.…”

“…This type of activity was observed for some other copper(II), nickel(II) and zinc(II) complexes derived from a pentadentate macrocyclic ligand. 8 The reference complexes were active against some microbial strains but their activity was ________________________________________________________________________________________________________________________ Available on line at www.shd.org.rs/JSCS/ (CC) 2020 SCS.…”