Studies On Spectroscopic Properties And Biological Activity Of N-aryl-n′-benzoylthiourea Pd(Ⅱ) Complexes

Thiourea and its derivatives have received increasing attention for a long timedue to their important applications dealing with biological activities, such asanticancer, antiviral and antibacterial, etc. Relying on the good chelate ability,thiourea and its derivatives also could be used in the extraction of trace metals and theseparation of platinum group metals. Moreover, they are wildly applied in thesynthesis of nonlinear material in the anion acceptor recognition.In this thesis, a series of N-aryl-N′-benzoylthiourea compounds were synthesizedand chosen to be ligands for palladium(II) complexes. Several new palladium(II)complexes were prepared. The ligand and palladium complexes were characterized.The ultraviolet-visible spectroscopy, fluorescence spectrometry, agarose gelelectrophoresis and their biological activities were studied. Main contents of the thesisare given as follows:Chapter Ⅰ: Review: The progress of N-aryl-N′-benzoylthiourea Pd(II)complexesThe properties, synthesis and application of aroylthiourea derivatives and theirpalladium complexes were reviewed in this chapter. The application status ofpalladium complexes in the chemistry and molecular biology were literatured.Chapter Ⅱ: Studies on synthesis and spectroscopic properties ofN-aryl-N′-benzoylthioureaA series of N-aryl-N′-benzoylthiourea compounds were synthesized. Theirstructures were characterized by element analysis， FTIR，IH and13C NMRspectroscopy. The fluorescence properties of these compounds were studied. It hasbeen concluded that the conjugate of P-π can increase fluorescence efficiency. Bothfluorescence intensity and Stock’s effect were directly impacted by substitutedproperties and positions.Chapter Ⅲ: Studies on synthesis and spectroscopic properties ofN-aryl-N′-benzoylthiourea Pd(II) complexesThree new N-aryl-N′-benzoylthiourea and Palladium(II) complex weresynthesized by the reaction of N-aryl-N′-benzoylthiourea with K2PdCl4inacetonitrile/aqueous solution. The composition and thermal stability of the complexes were characterized by molar conductivity, thermal analysis, IR, UV, etc. Both theligand and palladium complexes have fluorescent properties. The fluorescenceemission peak of three palladium complexes was found to be red shift compared withligands. The fluorescence intensity of palladium complexes was enhanced obviously.Chapter Ⅳ: Studies on biological activity of three N-aryl-N′-benzoylthioureaPd(II) complexesThe ligand and complexes have been evaluated for antibacterial activity againstEscherichia coil, Bacillus subtilis and Staphylococcus aureus in this section. Theresults indicat that all the complexes show the higher antibacterial activitiescompared with the ligands. The interaction of the complexes to DNA was investigatedby fluorescence spectroscopy and agarosegel electrophoresis. It was found that thecomplexes could bind to DNA by intercalative mode and cleave pBR322DNA in thepresence of H2O2.