<b>Synthesis and characterization of transition metal complexes derived from some biologically active furoic acid hydrazones</b>

Abstract

Two new physiologically active ligands, N'-2-[(E)-1-hydroxy-4-methyl-2-oxo-2H-8-chromenyl) ethylidene)-2-furan carbohydrazide (HMCFCH) and N'-2-[(Z)-1-(4-hydroxy-6-methyl-2-oxo-2H-pyranyl) ethylidene]-furan carbohydrazide (HMPFCH) and their VO(II), Mn(II), Fe(II), Co(II), Ni(II) and Cu(II) complexes have been prepared. The ligands and the metal complexes have been characterized by elemental analyses, electrical conductance, magnetic susceptibility measurements, UV-Vis, IR, and ESR spectroscopic data. Basing on the above data, Fe(II) and Co(II) complexes of HMCFCH and HMPFCH have been assigned a dimeric octahedral geometry. VO(II) complexes of HMCFCH and HMPFCH have been assigned sulfate bridged dimeric square pyramidal geometry. Mn(II) complex of HMCFCH has been assigned a dimeric octahedral geometry, where as Mn(II) complex of HMPFCH has been ascribed to monomeric octahedral geometry. Cu(II) and Ni(II) complexes of HMCFCH have been ascribed to a polymeric structure. Ni(II) complex of HMPFCH has been assigned a dimeric square planar geometry. Cu(II) complex of HMPFCH has been proposed an octahedral geometry. The ligands and their metal chelates were screened against S. aureus and P. aeruginosa. The ligands and the metal complexes have been found to be active against these microorganisms. The ligands show more activity than the metal complexes.

Synthesis, spectroscopic characterization and <i>in vitro</i> antibacterial activity studies of Cu(II) complexes derived from 6- hydroxyflavone Schiff bases

“…The measured molar conductance of the complexes in 10 -3 M dimethylsulphoxide determined as reported by Geary, (1971) are in the range of 20.4 -33.5 ohm -1 cm 2 mol -1 , which are relatively low, indicating their non electrolytic nature ( Table 3). The magnetic moments of all the complexes were found to be in the range of 1.9 -2.1 B.M at room temperature, suggesting an octahedral geometry around the copper(II) ions (Venkateswar et al, 2007). The solubility test (Table 4) showed that the compounds are insoluble in acetone, water and tetrachloro methane but soluble in DMSO, methanol and ethanol.…”