Bimetallic Complexes of Schiff Base Bis-[4-hydroxycuomarin-3-yl]-1N,5Nthiocarbohydrazone as a Potentially Dibasic Pentadentate Ligand. Synthesis, Spectral,and Antimicrobial Properties

The Schiff base bis-[4-hydroxycuomarin-3-yl]-1N,5N-thiocarbohydrazone, H2L, was prepared by the reaction of 4-hydroxycoumarine-3-carbaldehyde with thiocabohydrazide in 2:1 molar ratio. The ligand and its binuclear complexes with Cu(II), Ni(II), Zn(II), Co(II), Mn(II), Fe(III) and Cr(III) ions were characterized via elemental analysis, 1H NMR, mass spectrometry, infrared, and electronic spectra, as well as room temperature magnetic susceptibilities. Furthermore, the thermal stabilities of two representative complexes were also investigated. The Schiff base and its metal complexes were screened for their antifungal and antibacterial activities against different species of pathogenic fungi and bacteria and their biopotency have been discussed.