Study On Microwave-Induced Synthesis,Spectra And Electrochemical Of 4-Hydroxycoumarin And Its Derivatives

4-Hydroxycoumarin derivatives are of interest because of their bactericidal, insecticidal,anticoagulant and anti-HIV activities.They are also extensively used as optical brightening agents,dispersed fluorescent and laser dyes.For this reason,the optical and electrochemical propertities of novel derivatives,together with the development of new synthetic methods,are topics of growing interest for a great number of research groups.The synthetic progresses of coumarin and its derivatives were reviewed.Furthermore, a series of 4-hydroxycoumarin derivatives were synthesized and their optical and electrochemical propertities were studied.These studies would supply available informations and datas in life science.This thesis consists of four chapters,and the main contents are as follows:1.Coumarin derivatives have been playing important roles because of their important biological and optical activities.The recent advances in the synthetic methods of coumarin and its derivatives are reviewed.2.Three kinds of 4-hydroxycoumarin derivatives,3,3′-benzylidenedi-4-hydroxycoumarin,3,3′,3″,3′″-ethylenetetrakis-4-hydroxycoumarin and 4-hydroxycoumarin- 1,4-naphthaquinone have been synthesized from 4-hydroxycoumarin under microwave irradiation. Through change of reaction conditions,the best condition for the synthesis of 4-hydroxycoumarin was selected.Their structures were verified by elemental analysis,IR,¹H NMR,MS spectroscopy and X-ray measurement.3.The fluorescence and UV properties of aimed compounds were preliminarily studied and the relationship was found between the compounds' microcosmic structures and their corresponding optical properties.The results show that a bigÏ€-conjugated, symmetrical 3,3′,3″,3′″-ethylenetetrakis-4-hydroxycoumarin has better fluorescence in solution.When the concentration was in the range of 0.5～1.5×10^-4mol·L^-1,the fluorescence intensity linearly increased with decreasing concentration.In the range of pH 1.18 to pH 6.09 fluorescence intensity increases with increasing of pH,and in the range of pH 8.36 to pH 11.98 fluorescence intensity increases with decreasing of pH.Fluorescence enhancing was significantly observed in the presence of BSA,DNA.4.Electrochemical techniques were employed to study the electrochemical behavior in a KH₂PO₄-Na₂HPO₄ buffer solution of pH 7 and the interaction with BSA of 4-hydroxycoumarin. The experimental results show that the reduction wave detected in the solution was an irreversible reduction wave of 4-hydroxycoumarin involving 1e and OH⁺,and a complex was formed due to the reaction of 4-hydroxycoumarin and BSA.