【作者】 李苗；

【导师】 张彩红；

【作者基本信息】 山西大学 ， 分析化学， 2020， 硕士

【摘要】 硝基苯并呋咱（NBD）是苯并呋咱的7-位被硝基取代的杂环分子,当其4位连接一个给电子基团时,整个化合物自身会形成电子推拉效应,发射出荧光,因此在探针设计中常被作为经典的荧光团。含硫的生物小分子包括硫化氢（H₂S）和生物硫醇（RSH）在生理活动过程中起着重要作用。因此,本论文基于NBD构建了三种用于检测H₂S/RSH的荧光探针。第一章本章主要对NBD在荧光探针领域的研究进展作了综述。首先对苯并呋咱（BD）及其衍生物NBD的结构和性质进行了概述;其次,从检测对象和检测机理的角度,对近年来基于NBD的荧光探针的研究作了重点介绍;最后,基于此提出了本论文的立题背景、研究内容和创新性。第二章本章将苯并噻唑与硝基苯并呋咱（NBD）通过硫醚键连接合成了可区分小分子生物硫醇的荧光探针TBT-NBD。TBT-NBD通过Cys/Hcy诱导并重排产生相应的NBD胺基衍生物,而GSH仅诱导取代反应并产生相应的NBD巯基衍生物。NBD胺基衍生物在551 nm发射较强的荧光,可将Cys/Hcy和GSH区分开。探针TBT-NBD能对Cys/Hcy的识别选择性好,检测限低（分别为12.6 nM和20.4 nM）,且响应时间短（5 min）,另外,TBT-NBD也成功用于SNU-423细胞成像来测定细胞内源和外源的Cys/Hcy。第三章本章以对硝基苯甲酸和NBD哌嗪衍生物通过缩合构建了探针NA-NBD。探针为NBD胺基衍生物,其本身发射黄绿色荧光,与H₂S能发生特异性C-N键裂解反应,反应后变成NBD巯基衍生物,NBD巯基衍生物几乎不发射荧光,溶液具有独特的粉红色。因此可以从荧光猝灭和溶液颜色变化（浅黄色变为粉红色）两个方面实现对H₂S的检测。NA-NBD对H₂S的检测选择性好、灵敏度高,其线性范围在0-50?（44）,检出限可达3.07?（44）。第四章在第三章研究的基础上,将三苯胺羧酸通过哌嗪环与NBD缩合制备了一种新型的荧光探针TPA-NBD。TPA-NBD和H₂S反应发生C-N键裂解反应后,生成三苯胺酰胺化合物和NBD巯基衍生物,三苯胺酰胺化合物使荧光增强,而NBD巯基衍生物使荧光减弱,在两个不同激发波长下都能对H₂S选择性响应,显示不同的荧光特性。探针TPA-NBD在两个不同的通道都对H₂S的响应具有较高的灵敏度,检出限可低达0.70?M,且线性范围宽（0-125?（44））,并且双通道同时检测比单激发单发射检测的结果更准确可靠。更多还原

【Abstract】 Nitrobenzofuran（NBD）,7-NO₂ benzofurazine derivative,was a heterocyclic compound.The compound could emit fluorescence because of electron push-pull effect when an electron-donating group was connected to its 4-position.Therefore,it was often selected as a classic fluorophore in probe design.Sulfhydryl-containing biological small molecule,mainly including hydrogen sulfide（H₂S）and small molecule biothiol（RSH）,played important roles in physiological process.Based on these,three fluorescent probes based on NBD for detecting H₂S/RSH were constructed in this paper.Chapter 1: The research progress and status of fluorescent probes based on NBD were summarized in the chapter.Firstly,the structure and properties of BD and NBD were presented.Secondly,the recent researches of NBD fluorescent probes,including detection objects,detection mechanisms and applications were highlighted.Finally,the thesis background,research content and the innovation were brought forward based on these.Chapter 2: In this chapter,probe TBT-NBD for Cys / Hcy was synthesized through one-step reaction by connecting benzothiazole and nitrobenzofuran（NBD）.TBT-NBD was induced by Cys / Hcy,then rearrange to produce the corresponding amino-NBD derivative,while GSH only induced the substitution reaction and produced the corresponding thio-NBD derivative.The amino-NBD derivative showed strong fluorescence emission at 551 nm,so it could selectively recognize Cys / Hcy with low detection limits（12.6 n M and 20.4 n M,respectively）,and short response time（5 min）.In addition,TBTNBD was also successfully used for SNU-423 cell imaging to detect endogenous and exogenous Cys / Hcy.Chapter 3: The probe NA-NBD for H₂ S was constructed by the condensation reaction of p-nitrobenzoic acid and NBD piperazine derivatives.NA-NBD was amino-NBD derivative and emited a yellow-green fluorescent.It became thio-NBD derivative a specific C-N bond cleavage reaction with H₂ S.The thio-NBD derivative hardly emited fluorescence and its solution had a unique pink color.Therefore,H₂ S could be detected from two aspects: fluorescence quenching and solution color（from light yellow to pink）.NANBD had good selectivity and high sensitivity for H₂ S with a linear range of 0-50 m（44）and a detection limit of 3.07 m（44）.Chapter 4: Based on the research of Chapter 3,a novel fluorescent probe TPA-NBD was prepared by condensing triphenylamine carboxylic acid with NBD through a piperazine ring.Triphenylamine derivative and thio-NBD derivative were generated after the C-N bond cleavage reaction between TPANBD and H₂ S.The fluorescence of triphenylamine derivative enhanceed and the fluorescence of thio-NBD derivative weakened,which could selectively response to H₂ S at two different excitation wavelengths and display different fluorescence characteristics.TPA-NBD has high sensitivity and wide linear range(0-125 m（44）（8）to H₂ S and the detection limit can be as low as 0.70 mM.The detection results with dual-channel detection was more accurate and reliable than that with the single excitation and single emission detection.更多还原