Studies of Some New Biologically Active Ligands and Their Complexes Derived from Some Transition Metal Ions

Abstract

The metal complexes derived from new biologically active quinoline derivatives namely; 4-amino-5-(quinolin-8- yloxymethyl)-2,4-dihydro-[1,2,4]triazol-3-thione (L1), benzoic acid N′-[2-(quinolin-8-yloxy)-acetyl]-hydrazide (L2), [4-phenyl-5-(quinolin-8-yloxymethyl)-4H[1,2,4]triazol-3- ylsulfanyl]-acetic acid ethyl ester (L3) and [2-(quinolin-8- yloxy)-acetyl]-thiourea (L4) were prepared by reacting the quinoline derivatives with nitrates of zinc(II), copper(II), nickel(II), cobalt(II) and iron(III) in ethanolic medium. The metal:ligand ratio was found to be 1:2 by using the standard method of complexometric titration. The Fe(III) % in its complexes was estimated using spectrophotometric method. The structure of the isolated complexes were studied on the basis of their infrared spectra, elemental analysis (C, H, N, H₂O, M %), molar conductivity, thermal analysis (DTA/TG), mössbauer, magnetic susceptibility and computer modeling of the ligands. The mössbauer spectra of the iron complexes reflect the Fe(III) high spin complexes with octahedral structure. The complexes gave higher activity towards the microorganisms under consederation at 50 and 100 ppm rather than the organic ligands.