Synthesis and characterization of schiff base of 3-[(2-Hydroxy-phenylimino)-methyl]-6-methoxy-quinolin-2-ol and its metal complexes and their evaluation for antibacterial and antifungal activity

Abstract

A Schiff base of 3-[(2-Hydroxy-phenylimino)-methyl]-6-methoxy-quinolin-2-ol was synthesized by a 1:1 molar condensation of 2-Hydroxy-6-methoxy-3-quinolinecarboxaldehyde and 2-aminophenol. The metal (II) complexes were synthesized by refluxing the ethanolic solutions of the Schiff base and the chloride salts of the metals. Melting point, decomposition temperature, solubility, elemental analysis, fourier transform infrared spectroscopy, magnetic susceptibility and molar conductivity measurements were used to characterized the Schiff base and its metal complexes. The Schiff base is yellow and it has a melting point of 251 OC. The decomposition temperature of the Cd (II) and Cu (II) complexes were 282 and 270 OC respectively. The elemental analysis of the complexes established the formation of 1:1 metal - ligand ratio. The non-electrolytic natures of the complexes were revealed by the molar conductivity values. The behavior of the Schiff base and its coordination with the metal ions was suggested by the infrared spectral data via the azomethine nitrogen and hydroxyl oxygen after deprotonation. The solubility test of the Schiff base and its metal complexes were carried out by using different solvents. The antibacterial and antifungal activity were performed and discussed.