Bioactive Azamacrocyclic Zinc(II) Complexes: Synthesis and Characterisation

Abstract

Reduction of Me8[14]diene·2HClO4 (L·2HClO4) afforded three isomeric ligands (LA, LB and LC), among which LC underwent cyanoethylation with excess acrylonitrile to form the bis-cyanoethyl derivative (LCX). Reaction of LCX with zinc(II) chloride yielded the six-coordinate complex [Zn(LCX)Cl2], which subsequently underwent axial ligand substitution with KSCN, KNO3, NaNO2, KBr and KI to produce a series of octahedral zinc(II) complexes, [Zn(LCX)(X)2] (X = NCS, NO3, NO2, Br or I). All the Zn(II) synthesised complexes were characterized using various analytical and spectroscopic techniques. Their antibacterial activity was evaluated against four selected bacterial strains and most of the complexes exhibited good antibacterial activity against the tested bacteria.