一种选择性SO_(2)荧光探针的合成及性能

Synthesis and Properties of A Selective SO_(2) Fluorescent Probe

以4-(二乙氨基)水杨醛为原料,经Knoevenagel缩合反应、Vilsmeier反应以及Wittig反应得到中间体3,以2,3,3-三甲基-3 H-吲哚为原料,经亲核取代得到中间体4;3与4发生缩合反应得到含半花菁结构的香豆素类SO_(2)荧光探针PA1,其结构经^(1)H NMR、^(13)C NMR和HR-MS(ESI)确证。该探针具有良好的水溶性,可以快速检测外源性SO_(2),检出限为0.38μM,响应时间为3 min。探针于498 nm处的荧光强度随着SO_(2)浓度增加而增强,当SO_(2)浓度为0~120μM时,荧光强度与浓度的线性相关系数为0.998。

Intermediate 3 was synthesized from 4-(diethylamine)salicylaldehyde by Knoevenagel condensation reaction,Vilsmeier reaction and Wittig reaction.Intermediate 4 was synthesized from 2,3,3-trimethyl-3 H-indole by nucleophilic substitution reaction.Then,a coumarin-based SO_(2) fluorescent probe PA1 containing hemicyanine was synthesized by condensation between 3 and 4,and its structure was characterized by^(1)H NMR,^(13)C NMR and HR-MS(ESI).PA1 shows good water solubility and can detect exogenous SO_(2) rapidly with a detection limit of 0.38μM and a response time of 3 min.The fluorescence intensity of the probe at 498 nm is linearly related to the concentration of SO_(2) in the range of 0-120μM,and the correlation coefficient is 0.998.