Fluorescent Labeling Reagents To Be Used In Chinese Medicine And Medicinal Plants Analysis

There are a variety of chemical constituents in traditional Chinese medicine (TCM). It is much more complex in Fufang TCM which constituted by several single TCM. It is a challenge to the analysis and quality control of Fufang TCM. Thus a selective and sensitive analytical method was urgent needed for the complex system of TCM. This is a key point for the analysis and quality control of TCM. The HPLC is a good choice for the complex system. But the most constituents in decoction of TCM are polar compounds, and difficulty to separate in reverse phase HPLC. A lot of constituents are lack effective UV absorbtion and difficulty to detect. Both problems of lack sensitive detection and effective separation call new strategy, in ordor to fufill the need of sensitive and selective analytical methods of TCM.During the study of biomimetic synthesis of monoterpene indole alkaloids, it was found that secologanin underwent different rearrangement pathway to form different products at different pH conditions. According to this observation, it was speculated that the one important reason of structure diversity over four thousands monoterpene indole alkaloids in the different plants could be pH induced rearrangement. If the speculation could be confirmed, it could help to elucidate the biosynthesis pathway of these alkaloids, and increase target production by chemical and biotechnological method to influence the pH. Therefore, it could have academic significance and application value.In this thesis, a series of fluorescent probe for pH determining and fluorescent regents for selective labelling aldehyde, phenol, amino acid were designed and synthesized, respectively. Totally,16 fluorescent regents are synthesized for the first time, the structures are characterized by IR and NMR spectroscopies.Their fluorescence properties were examined and the absorption and emission maxima. The relationships between their fluorescence properties and pH value were examined.7-Amino-4-methylcoumarin was synthesized from phenols and ethyl acetoaceate via Pechmann condensation using H2SO4 as catalyst under solvent by three-steps. The aldehydes were selectively labelled by the designed coumarin probe. This method uses the Hantzsch ester as reducing agent to transfer hydrogen and proceeds in the presence of molecular sieves and catalytic amounts of thiourea. 7-hydroxy-4-methylcoumarin was synthesized from phenols and ethyl acetoaceate via Pechmann condensation using H2SO4 as catalyst under solvent-free condition. The amino acids were labed by the designed coumarin and fluorescein regent, respectively. The stru-ctures were characterised by IR and 1H NMR spectroscopies.