Spectroscopic Properties Of Metal Carboxyl Complexes And Their Interaction With Biomolecules

Metal-Oxo-centered,carboxylate-bridged clusters have electronic,magnetic,catalytic properties and also have fascinating structures in crystal engineering,therefore,they are important in catalytic chemistry,molecular recognition,bioscience and other aspects.These properties have been extensively studied by many chemical researchers.In this paper,a novel functional ligand have been synthesized,the carboxyl group in the ligand can reaction with Fe(III),Cu(II)to form the different structures of complexes respectively,and analyzed the structural features?basic properties,studied the potential application in biological sciences.The main results of this paper are concluded as follows:(1)The synthesized and characterized of functional ligand:2-(Methylthio)Benzo[d]Oxazole-5-Carboxylic AcidWith methyl 4-hydroxybenzoate as raw material,the ligand was synthesized by nitration,reduction,cyclization and methylation,the intermediate and target products have been characterized by Elemental analysis?FT-IR?HPLC-MS?1HNMR.Using the method of solution evaporation to obtain the crystal and the structure was characterized by X-Ray single crystal diffractometer to further confirm the ligand's structure.(2)The structures of two new Oxo-centered,carboxylate-bridged tri-nuclear iron(III)complexes and study of spectroscopy and electrochemical propertiesWith 4-(Methylthio)benzoic acid and 2-(Methylthio)Benzo[d]Oxazole-5-Carboxylic Acid as ligands to reaction with iron(III)ions to form two complexes(1,2)respectively.The two complexes have been characterized by Fourier Transform Infra-Red(FT-IR),Ultraviolet-visible(UV-Vis),X-Ray single crystal diffractometer,surface-enhanced Raman scattering(SERS)and Thermogravimetric analysis(TGA)/Differential scanning calorimetry(DSC),electrochemical methods.The group-SCH3 has been introduced to periphery of the complexes,which could be self-assembled to the surface of electrode which exhibiting an irreversible process,meanwhile the complexes can interaction with silver nanoparticles to study the surface-enhanced Raman scattering which present stronger Raman signal intensity.(3)The synthesis of complex 3 and its application in bioelectrochemical sensors,and the study of interacting with DNA molecularUsing 2-(Methylthio)Benzo[d]Oxazole-5-Carboxylic Acid as main ligand to reaction with copper(?)ions to form complex 3 which characterized by FT-IR?UV-Vis and X-Ray single crystal diffractometer.The electrochemical properties of complex 3 have been studied.The chitosan and complex 3 modified glass carbon electrode(3/CS/GCE)was fabricated by adsorption and the electrode exhibited a good electrocatalytic activity to dopamine,the oxidation peak current of complex 3 in the range of 8.5×10-7-3.5×10-5 M showed linear correlation with concentration of dopamine in the solution.Meanwhile,the interaction modes of complex 3 with DNA have been studied.The binding constant between complex 3 and DNA has been detected by UV-vis spectroscopy.Through the spectroscopic methods,thermodynamic parameters,effect of ionic strength and viscosity measurements,it suggests that the interaction mode between complex 3 and DNA was groove and electrostatic binding.