Coordination Driven Design and Biological Potentials of Mixed-Ligand Complexes Containing Diphenylmethanonehydrazone with 1, 10-Phenanthroline

Abstract

Mn(II), Fe(II), Co(II), Ni(II) and Zn(II) complexes of diphenylmethanone hydrazone with 1, 10-phenanthroline as secondary ligand has been synthesized. All compounds were characterized through CHN micro-elemental analysis, melting point analysis, solubility analysis and spectroscopic analysis (FTIR and UV-visible). The results of partial elemental analysis are in agreement with assigned formulations, while melting points of the complexes are higher as compared to the derived ligand. Spectroscopic analysis results confirmed the coordination of diphenylmethanonehydrazone to the various center metals in bidentate fashion via the azomethine nitrogen (C=N) and the H-N-H amide group. Similarly, the secondary ligand; 1, 10- phenanthroline also produced a bidentate chelate with interactive metal ions using the heterocyclic imine (C=N) bands. All the results suggested octahedral geometry to the complexes and have [M(L₁)(L₂)Cl₂], where L₁= diphenylmethanonehydrazone, L₂ = 1, 10-phenathroline and M = Mn(II), Fe(II), Co(II), Ni(II) and Zn(II). The IR spectra of the complexes were assigned and compared with the data in literature. In-vitro antifungal activity of these compounds was determined using our (4) pathogenic fungi (Aspergillus niger ATCC16404, Candida albicans ATCC10231, Trichoderma longibbrachiatum ATCC18648 and Rhizopus stolonifier ATCC14037). Both the derived ligand and the mixed-ligand complexes were active against fungal strains. The screening revealed an increased activity of the complexes against the fungal isolates compared to the free ligand. Fe(II) complex, showed highest activity among the complexes screened, however, other complexes displayed considerable antifungal activity