Synthesis, structural investigation and antimicrobial properties of macrocyclic zinc(II) complexes with N2O2-donor schiff bases incorporating 1,2,4-triazole ring

A novel series of nano-sized zinc(II) complexes of type [{Zn(M)(H2O)2}(CH3COO-)2] (where M = macrocyclic ligands) has been synthesized by the in situ reactions of Schiff bases derived from 3-(phenyl/substituted phenyl)-4-amino-5-hydrazino-1,2,4-triazoles, salicyldehyde/ 2-hydroxy-1-naphthaldehyde and 1,4-dibromobutane/1,5-dibromopentane in presence of zinc(II) acetate dihydrate in absolute ethanol. The structures of all these zinc(II) complexes were established on the basis of elemental analyses and spectral data (IR, 1H NMR and 13C NMR). Scanning electron microscopy studies have been carried out to investigate the particle size and surface morphology of a particular complex while thermal studies confirm the presence of coordinated water molecules in all the zinc(II) complexes. The antimicrobial effects of all the synthesized complexes were studied against different species of pathogenic fungi and bacteria.