Design And Synthesis Of Isomeric Pure Rhodamine-Based Fluorescence Probe

Rhodamine fluorescent dyes have a wide range of applications,due to its excellent photophyscial properties and unique structural characteristics.Rhodamine derivatives exist equilibrium between spirolactam and ring-opened amide forms.Rhodamine derivatives which have spirolactam structure are colorless and non-fluorescence.Spirolactam structure will be changed into ring-opened amide form via coordination with metal cations,giving rise to the appearance of the pink color and strong fluorescence.In recent years,with the requirements of the fluorescent probe performance is getting higher and higher,the modification of rhodamine base ring structure have attracted much attention.In this paper,two kinds of 5-and 6-carboxy rhodamine derivatives were designed and synthesized base on the research of reaction activity of carboxyl groups of 5(6)-carboxy-rhodamine,which are 5-and 6-carboxy rhodamine-triethylene glycol Derivatives,5-and 6-carboxy rhodamine-cholest erol derivatives.The recognition properties of these derivatives were studied by UV spectroscopy and fluorescence spectroscopy.The results showed that these rhodamine derivatives had a selective response to Cu2+ and could be used as a Cu2+ fluorescent probe.The main contents of the thesis are as follows:1.5(6)-carboxy-rhodamine was prepared by using 3-diethyla-minophenol and trimellitic anhydride in dry toluene solution.5-carboxylated rhodamine(1a)and 6-carboxy rhodamine(2b)were isolated by appropriate eluent proportions.Then 5-and 6-carboxy-rhodamine were selectively esterified and hydrazine hydrolyzed to give 5-and 6-carboxy rhodamine-triethylene glycol derivatives,5-and 6-carboxy rhodamine-choleste-rol derivatives.In the process of esterification of 5(6)-carboxylated rhodamine,it was found that the carboxylation activity at the 3-position was lower than that of 5-and 6-position carboxyl groups.However,in the process of hydrazination,it was found that the carboxylation activity at the 3-position was higher than that of 5-and 6-position carboxyl groups.By controlling the reaction conditions,the hydrazide can be selectively formed in the 3-carboxyl group,and the carboxyl group is formed at the 5-or 6-carboxyl group.The regioselectivity has not been reported in the literature.2.Rhodamine hydrazide is a classic copper ion recognition group.In this paper,5-and 6-carboxy rhodamine water-soluble probes T1 and T2 were designed and synthesized in which rhodamine hydrazide is used for the recognition group and triethylene glycol is used for hydrophilic group.Under the same test conditions,the similarities and differences of T1 and T2 were investigated by UV and fluorescence spectra.The results show that the probes T1 and T2 have good water solubility and wide pH stable region,and have good selectivity and anti-interference ability to copper ions.But the probes T1,T2 have different fluorescence emission wavelengths and sensitivity to ion recognition.3.In this paper,two kinds of cell membrane targeted fluorescent probes of copper ion,T3 and T4 were designed and synthesized,in which the hydrazide is used for the recognition group and the cholesterol is used for the targeting group.UV spectroscopy and fluorescence spectroscopy research showed that the probe T3 had good selectivity to copper ions in DMF solution,but the detection limit was lower than T4.The probe T4 in the acetonitrile solution have a good selectivity for copper ions,but the anti-interference ability is weaker than T3.