Synthesis,Structure And Spectral Properties Of Flavonoid Carboxylic Acids And Their Complexes

The excellent biological activity of flavonoids can be used as antioxidants,plant growth regulators and enzyme inhibitors.It is commonly used as a valuable drug in the treatment of hypertension,and cancer.At present,the extraction technology of plant flavonoids is very successful and can be industrialized.However,flavonoids in plants have fixed molecular structures and are difficult to purify.Chemists have developed the chemical synthesis method of flavonoids to realize the diversity of flavonoids.In view of the heavy pollution and low yield of the current synthesis of flavonoids,green synthetic method is worth of further exploration.Some studies show that the flavones modified by carboxyl group and hydroxyl group have strong physiological activity and even new pharmacological activities,such as antispasmodic and antiallergy.But so far,few researches have been done on carboxylic acid flavonoids,which to a great extent limit the practical application of carboxylic acid flavonoids derivatives in medicine,pharmacy and magnetism.Therefore,it is of great scientific significance to study the synthesis and optical properties of flavonoids and their complexes.In this thesis,based on the previous research and knowledge accumulation of flavonoids and carboxylate complexes,a series of carboxylic flavone compounds were synthesized by modifying the hydroxyl group of the flavonoid compound to the carboxyl group.Then,the complexes of the transition metal with flavonoid carboxylate were further synthesized,and their crystal structure and spectral properties were studied theoretically and experimentally,which is expected to be beneficial to the further development of carboxylic acid flavonoids.The full text is divided into four parts.The contents are summarized as follows:The first part of the paper gives a detailed overview of the synthesis and application of flavonoids,flavonoids and derivatives of flavone derivatives,and the research progress of carboxylic complexes,and puts forward the basis and purpose of this topic.In the second part,a series of new flavanone compounds were designed and synthesized.Two kinds of eight kinds of carboxylic acid flavones were synthesized from 3-hydroxy flavone,7,8-hydroxy flavone,kaempferol,quercetin,apigenin,carietin,cariotin and luteolin.One class was flavonoid containing C epoxide,the other was flavone without C epoxide.The compounds were characterized by 1H NMR and IR.The third part of the thesis syntheses the complex of 3-oxanone flavone,and obtains the single crystal of the copper cobalt carboxylic acid complex.The metal complexes are characterized by infrared spectroscopy(IR),and the crystal structure of the complexes is studied by the X ray single crystal diffraction instrument.In addition,thermogravimetric studies of copper cobalt carboxylic acid complexes show that these two kinds of single crystals have strong thermal stability and can be used in the field of hot metal materials.The fourth part studies the UV Vis absorption spectrum and fluorescence emission spectrum of carboxylic acid flavone complex and carboxylic flavone.The UV visible absorption spectrum shows that the maximum absorption wavelength of the compound has no displacement,but under the alkaline condition,the conjugated effect of carboxyl oxygen atoms and connected carbon is strengthened,and the maximum absorption wavelength of the compounds is red shift in different degrees.The results of the same fluorescence emission spectra are similar to those of UV Vis absorption spectra.In addition,the fluorescence emission spectra of the flavone carboxylic compounds of different metals were also studied.The results showed that the carboxylic flavones were more easily formed with copper ions and cobalt ions,and the coordination of copper ions reduced the fluorescence intensity of the ligands.At the same time,the UV absorption visible spectrum and fluorescence spectrum properties of the complexes were tested.The maximum wavelength of the UV absorption and fluorescence emission peaks could be red shift because of metal chelation,and the complex could be used as the latent material of the sulfur ion probe.