The New Carbopyronine Fluorescent Probe Design And Synthesis Of Research

Calcium was well known as the'life metal', playing a very important role in all aspects of heredity and regulating physiological functions. Consequently, it is very important to explore the method of measuring intracellular Ca2+ concentration. Fluorescent probe is widely used in detecting the intracellular Ca2+ concentration. Although many Ca2+ fluorescent probes have been designed, there is still not a single fluorescent probe which can meet all testing requirements. It is an attempt in this thesis to design and synthesize a novel cell Ca2+ fluorescent probe with large fluorescence quantum yields, high photostability and near-infrared excitation, in order to enhance the biocompatibility and reduce the background fluorescence.Carbopyronine fluorescent dyes have unique photochemical and photophysical properties, whose structures are very similar to those of the rhodamines. However, its absorption and fluorescence are shifted remarkably towards longer wavelengths. There are so many advantages of carbopyronine fluorescent dyes such as high fluorescence quantum yields, low intersystem crossing rate, which make carbopyronine fluorescent dyes become the ideal fluorescent chromophores. In view of this facts, the design and synthesis of the novel carbopyronine fluorescent compounds are very significant in the basic research and application.In this thesis, the progress of research on Ca2+ fluorescent probes and carbopyronine fluorescent compounds was reviewed. Furthermore, the synthesis method of the novel carbopyronine fluorescent probes has been designed.1. The synthetic route has been designed from aniline and 3-aminobenzoic acid by a series of reactions, such as the reaction of amino-allylation, formylation, esterification, reduction, addtion of Grignard reagent, oxidation, an so on. Some unreported intermediates have been obtained, whose structure was characterized by IR, NMR, MS.2. The synthetic method of the key intermediate N, N-dialkyl anilines were studied, the plausible reaction mechanism of synthesizing the compounds in the presence of a catalytic amount of potassium iodide was proposed, the effects of steric hindrance and electron on reactants were also investigated. 3. The direct cyclization of the methylene-bridged tertiary alcohol in the presence of the Lewis acid was investigated, the reaction mechanism was discussed. The effects of different Lewis acid on the yield of the reaction and the fluorescence properties of the compounds were also studied.4. Some reaction mechanisms in the synthetic route were discusses and some reaction conditions have been optimized, which laid the solid theoretical foundation for the further research work.