Isolation, Characterisation and Antimicrobial Activity Studies of the Mixed Li and Complexes of Cd(II) with 8-Hydroxyquinoline and Various Salicylic Acids

Department of Chemistry, Nagarjuna University, Nagarjunanagar-522 510

Govt. Medical College, Guntur-522 004

A series of mixed ligand complexes of Cd(II) with the general formula CdL₁L₂ (where L₁ =8-hydroxyguinoline ; L₂ =salicylic acid, 5-chloro, 3,5-dibromo, 3,5-diiodo, 3,5- dinitro, acetyl salicylic acids) are isolated in pure state and characterised by elemental analysis and infrared data. The low molar conductance of these complexes in DMF indicates non-electrolyte nature of these complexes. The antimicrobial activity of these complexes against 14 pathogenic bacteria and 5 fungi is studied under various conditions. Even though one 8-hydroxygulnoline molecule in the binary cadmium-oxinate  is replaced by a low cost fungicide like salicylic acid in the formation of mixed ligand complexes, these mixed ligand complexes are found to posses fairly higher antimicrobial activity against several organisms than the binary cadmium^­oxinate. The lypophIlic tendency of these complexes is determined and its influence on the antimicrobial activity is critically examined. The probable mechanism of the toxic action of these complexes against various organisms is discussed.