Synthesis, Complexation and Biological Activity of New Isatin Schiff_bases

Abstract

Some new Schiff-bases derived from condensation of 3-hydrazono-2-oxo-2,3-dihydroindol-1-yl)-acetic acid hydrazide (3) with benzaldehyde, p-methoxybenzaldehyde and p-chlorobenzaldehyde have been synthesized in high yields via refluxing in EtOH in the presence of catalytic amount of acetic acid. The synthesized compounds have been characterized by elemental analysis, IR, I H-NMR and mass spectra. Cu(II), Zn(II), Mn(II) and Fe(III) complexes of the synthesized compounds were prepared and characterized by elemental analysis, conductivity measurements, IR, UV-Vis. spectra and magnetic moment measurements. TGA and DTA confirm the chemical formulation of the complexes and their thermal decomposition were evaluated. Antimicrobial activity of the synthesized compounds have been screened using the desk diffusion method with different strains of bacteria: Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli and Proteus volgaris were used.

Isatin – a potent anti-microbial agent

“…Chelation theory explains the increased activity of the complexes as chelation decreases metal ion polarity. In addition, chelation also improves chelate lipophilic nature which is useful for penetration into microorganism (Sallam et al, 2012).…”