Synthesis And Antibacterial Activity Of Complexes With Schiff Bases Derived From Memantine And Chlorosalicylaldehyde

Schiff base and its metal complexes have indispensable applications in many fields such as biological activity,catalytic chemistry,thermodynamics,electrochemistry,material chemistry and magnetism.Memantine is a non-competitive antagonist with a medium affinity and has been used to treat Parkinson's disease,dementia and other diseases.In this article,two Schiff bases of memantine amine 5-chlorosalicylald-ehyde and 3,5-dichlorosalicylaldehyde were designed and synthesized.Then,six complexes corresponding to copper,cobalt or zinc atoms were synthesized with these two Schiff ligands,and the obtained compounds were characterized and tested for their antibacterial properties.The main contents are as follows:1?Two Schiff base ligands:C19H24ClNO(HL1)and C19H23Cl2NO(HL2),were obtained in ethanol solution from memantine amine 5-chlorosalicylaldehyde and 3,5-dichlorosalicylaldehyde.Then,two schiff bases were used as raw materials,under the action of adding NaOH,they reacted with hexahydrate cobalt chloride,dihydrate copper chloride and anhydrous zinc chloride respectively,and 6 corresponding metal complexes were obtained:C38H46Cl2CuN2O2(1),C38H46Cl2-CoN2O2(2),C38H46Cl2ZnN2O2(3),C38H44Cl4CuN2O2(4),C38H44Cl4CoN2O2(5),C38H44Cl4ZnN2O2(6).2?Six ideal single crystals were obtained by solvent evaporation method and tested by X-ray diffraction.By analyzing the single crystal data,it was found that each complex molecule was composed of one metal atom and two Schiff base ligands deprotonized.3?Two ligands and six complexes were characterized by melting point determination,elemental analysis,IR,UV,1H NMR and X-ray powder diffraction.According to the analysis,the crystal samples of the six complexes were all pure compounds,which further explained the consistency of the single crystal structure test and analysis.4?The antibacterial properties of two ligands and six complexes were tested.At the concentration range of 10-1-10-4 mol/L,the two ligands could inhibit the three strains.Complex 3 has good antibacterial effect on the three kinds of bacteria.