Studies on copper(II) complexes of N-pendant macrocyclic ligands

Abstract

Naturally occurring azamacrocyclic metal complexes such as haems, chlorophyll, vitamin B12, and the factor F430 carry pendent ring substituents and axial co-ligands that act as functional components in these important biological systems. Design of related systems with structural features related to their natural counterparts is thus a multifarious challenge. With this in mind, we have recently reported on the characterization and antimicrobial activities of tetraazacyclotetradecanes and their Ni2+ complexes. Here, we present results on modified N-pendent ligands and their Cu2+ complexes: The interaction of two isomers of 3,5,7,7,10,12,14,4,8, LB and LC (differing (2)˚} has been determined by X-ray crystallography. The copper centre is coordinated to an N4 donor set of LCZ1 in a square planar geometry. The antifungal and antibacterial activities of the compounds have been studied against some phyto-pathogenic fungi and bacteria. Generally, the complexes exhibit a more pronounced antimicrobial activity than the parent ligands.