Study On Novel Naphthalimide Nucleic Probes And Their Photochemical Reactions

This thesis was divided into two parts.In the first part, four novel fluorescence probes, N,N'-Bis[hydoxyethyl] -1,4,5,8-naphthalene diimide(NDI1), N,N'-Bis[carboxymethyl]-1,4,5,8-naphthalene diimide (NDI2), N,N'-Bis[carboxypropyl]-1,4,5,8- naphthalene diimide (NDI4) and N,N'-Bis [carboxyamyl]-1,4,5,8-naphthalene diimide (NDI6), were synthesized, in which the synthesis of NDI4 and NDI6 have not been reported. The synthetic procedures of the four probes were studied.The UV absorption, fluorescence emission spectroscopy and electrochemical behavior of the four naphthalene diimides were studied. It was found that the probes exhibited strong UV absorption and fluorescence emission. Therefore these probes can be employed as potential fluorescence probes. The reduction potentials were measured by using cyclic voltammetry. The fluorescence lifetime and energy of LUMO were calculated and elucidated. The fluorescence quenching of NDI2,NDI4, NDI6 by a series of nucleic acids and their precursors were examined. It was found that their fluorescence could be apparently quenched by thymine, adenine, uracil, cytosine, guanine, deoxyguanosine, ctDNA and ssDNA. The fluorescence quenching rate constants were also determined, indicating that the quenching ability of the nucleic acids is stronger than their precursors. The measured quenching rate constants are within the order of 10¹⁰ M^-1S^-1, which indicated that the quenching is diffusion-controlled and characteristic of electron transfer mechanism.In the second part, two photochemical reactions were explored. Two compounds, N-allylmorpholine and 3-morpholino-1-phenylpropane-1-one, were synthesized. The intramolecular electron transfer reactions of the morpholines as electron donors and organic substrates including olefins and carbonyl compounds as electron acceptors were studied. In addition, three 1,8-naphthalimides were synthesized and their photochemical reactions were investigated. The intramolecular electron transfer reactions were also discussed.