【作者】 王仲如；

【导师】 双少敏；

【作者基本信息】 山西大学 ， 药物分析学， 2006， 硕士

【摘要】 第一章:本章简要概述了糖的基本结构与性质、硼酸衍生物与糖的作用机理及硼酸衍生物对糖分子识别的研究现状。 第二章:本章采用荧光光度法,紫外可见分光光度法研究了新的具有分子内电荷转移性质的硼酸衍生物:对-二苯氨基苯基硼酸（DPBA）对单糖分子的识别作用。考察了在含20%乙醇的水溶液中,溶液的pH值及各种单糖（D-果糖、D-半乳糖、D-甘露糖、葡萄糖）的浓度对DPBA荧光光谱及紫外光谱的影响。实验发现随着溶液pH值的增大,DPBA荧光光谱蓝移,荧光强度降低,这是由于高pH值下,硼原子由sp²杂化态转变为了sp³杂化态,使硼酸基团得电子能力降低,阻止了DPBA分子内的电荷转移。从实验中还可以观察到,在pH=8.0的水溶液中,随着糖浓度的增加,DPBA荧光光谱明显蓝移,荧光强度显著降低,且都有一等发射点出现。同时通过非线性拟合求得DPBA与D-果糖、D-半乳糖、D-甘露糖及葡萄糖的结合常数分别为5264.5、895.4、689.6和637.1 L/mol。实验现象表明对-二苯氨基苯基硼酸与D-果糖的结合能力远远超过其它三种单糖,说明DPBA能对D-果糖进行很好的选择性识别。 第三章:本章采用合成的具有分子内电荷转移性质的硼酸衍生物:对-二苯氨基联二苯基硼酸（DBBA）作为荧光探针对各种单糖分子进行识别研究。实验表明,在pH=8.0的乙醇水溶液中(V_乙醇:V_水=1:4),化合物DBBA的荧光光谱随着各种糖浓度的增大,荧光强度不同程度的升高,荧光峰位均微弱蓝移,且都有一等发射点出现。通过非线性拟合可以发现拟合曲线与实验值都能够很好的吻合,表明DBBA与D-果糖、D-半乳糖、D-甘露糖及D-葡萄糖分子间的结合计量比都均为1:1,并计算它们的结合常数。DBBA与D-果糖的结合常数比与其它糖的结合常数大10倍多,DBBA识别单糖分子的顺序为果糖（4291.6 L/mol）>甘露糖（383.6 L/mol）>半乳糖（255.3 L/mol）>葡萄糖（50.9 L/mol）。说明DBBA对D-果糖的选择识别性很高。 第四章:本章采用荧光光谱法研究了对-二苯氨基苯基硼酸（DPBA）与羧甲基-β-环糊精（CM-β-CD）形成的包合物对D-果糖、D-甘露糖、D-更多还原

【Abstract】 Chapter 1: The basic structure and property of monosaccharide had been introduced and the mechanisms of the fluorescence probe containing boronic acid group for saccharides recognition were summarized. The recent development of the interactions between the compound containing boronic acid group and saccharides was described further. Chapter 2: P-(Diphenylamino) phenyl boronic (DPBA) as a novel type of fluorescent probe for monosaccharides have been studied by fluorescence spectroscopy. With increasing pH and adding of sugars, the form of boronic acid group was changed from the neutral form with sp~2 -hybridization to the anionic form with sp~3-hybridization. This change induced a blue shift of about 50 nm and a dramatic decrease of intensity in the emission spectrum of DPBA .The biding constants were obtained by fitting the titration curves against monosaccharides. The binding constants followed the order: D-Fructose (5264.5 ± 46.3L/mol)? D-Galactose(895.4 ± 27.7L/mol)>D-Mannose (689.6 ± 30.2L/mol) >Glucose(637.1 ±21.3 L/mol). The results suggest DPBA can be used to recongnized D-fructose with high selectivity .The intramolecular charge transfer (ICT) mechanism was employed.Chapter 3: A novel compound 4-(diphenylamino) biphenyl-4’-boronic acid (DBBA) was synthesized as a novel type of fluorescent probe for monosaccharides. The ability of DPBA to interact with gluctose, D-fructose, D-galactose and D-mannose was systematically investigated by steady-state fluorescence spectrum method. The effect of various monosaccharides (gluctose, D-fructose, D-galactose, D-mannose) concentration on the biding process was discussed in detail. The biding constants were obtained by fitting the titration curves against monosaccharides. The binding constants followed the order: D-Fructose (4291.6 ± 47.9 L/mol)>> D-Galactose(383.6 ± 6.9 L/mol) > D-Mannose(255.3 ± 5.5 L/mol) > Glucose (50.9 ± 1.0 L/mol). The intramolecular charge transfer (ICT) mechanism was employed. Chapter 4: The inclusion complexe of p-(diphenylamino) phenyl boronic acid (DPBA) with carboxymethyl-(3-Cyclodextrin (CM-p-CD) as a fluorescence probe for monosaccharides recognition in water has been designed. The fluorescence intensity of DPBA is enhanced by forming an inclusion complex of DPBA-CM-P-CD. The inclusion complexe DPBA-CM-(3-CD showed large spectral shifts in the emission wavelength and a significant intensity charge on binding saccharides. When D-Fructose interacted with DBBA-CM-P-C in water containing 1% ethanol, the emission maxima from 421nm shifts to 383nm(A?x=306nm). This phonomina can be explained by the intramolecular charge transfer (ICT) mechanism. The 1:1 binding constants obtained by fitting the titration curves against monosaccharides and the binding constants followed the order: D-Fructose (1714.2 ± 70.4 Lmol"’)? D-Mannose(409.5±31.2 Lmol"1) > D-Galactose(292.6 ± 24.5Lmol’’) = Glucose (221.9+ 15.2 L mol’1).Chapter 5: The interaction mechanisms of P-(Diphenylamino) phenyl boronic (DPBA) ^ 4-(diphenylamino) biphenyl-4’-boronic acid (DBBA) and DPBA- carboxymethyl-(3-Cyclodextrin with monosaccharides have been investigated briefly. The intramolecular charge transfer (ICT) mechanism was employed. Phenylboronic acids are weak Lewis acids with pKa. values ~9. Formation of a boronate ester via interaction with a monosaccharide increases the electrophilicity of the boron group, thereby reducing its pKa value to~6. At pH values between 6.5 and 8.5, the boronic acid exists in its neutral form;however, in the presence of a sugar, it exists in its anionic form. This change in the electronic properties of the boron group leads to the loss of ICT effect and results a blue shift and the change of the intensity.更多还原