【作者】 孙宏元；

【导师】 郝爱友； 徐桂英；

【作者基本信息】 山东大学 ， 有机化学， 2009， 博士

【摘要】 超分子主体化合物环糊精以其良好的生物相容性、可修饰性,在人工主体的模拟设计中越来越受到重视。其中,β-环糊精作为目前工业化生产规模最大的环糊精,以其优良的性质、相对低廉的价格正日益受到广泛的应用与开发。但是母体β-环糊精分子本身作为主体模型在具体应用中还有一定的局限性,比如β-环糊精在紫外、荧光等光谱中则是惰性的,缺少显示电子转移、光致变色等的功能性基团,难于借助各种必要的光学仪器,研究其与客体分子相互作用等;另外,母体β-环糊精缺少酶体上的有效功能点,为增加其分子模拟识别（PatternRecognization,PR）能力,使之具有酶功能,还需要在环糊精分子上引入一定功能基团将其修饰成为功能性β-环糊精衍生物;此外,β-环糊精分子在水中的溶解度较小,也使其应用性受到一定的限制。对β-环糊精进行适当的化学修饰以获得性能优异的β-环糊精功能主体模型并拓展其应用领域是很有必要的。本论文的研究内容主要有4部分组成,其具体内容如下:一.羟烷基-β-环糊精型超分子主体化合物的合成及性能1.合成了一种新的水溶性环糊精衍生物6-O-（2-羟基丁基）-β-环糊精,并合成了系列环糊精衍生物,6-O-（2-羟基丙基）-β-环糊精、2-O-（2-羟基丙基）-β-环糊精、2-O-（2-羟基丙基）-β-环糊精,为新型超分子主体化合物的设计,合成,应用提供了对比研究的基础。2.采用紫外可见光谱法研究主客体的包结行为,采用圆二色光谱法研究主客体可能的结构,并有机地将两种手段结合起来,对主客体包结结构进行解析,为研究主客体之间的相互作用,模拟认知生命体系运转和生命过程,发展新催化体系提供较为有效的理论基础。3.采用结构相关的三种分子甲基橙、甲基蓝、甲基紫作为客体分子,以不同取代面的,含有同系结构基团的环糊精衍生物作为主体分子,研究主客体之间的相互作用,发现在主客体分子相互作用的过程中大小/形状匹配,亲水作用,疏水作用,空间位阻等弱的相互作用力对包结物的形成影响较大。为系统研究主客体之间的相互作用,理解超分子化学体系中的作用力,提供了具体的证据。二.甜菜碱基环糊精的合成及其在毛细管电泳中的应用1.采用两种方法将具有良好生物活性的甜菜碱通过稳定的价键结构连接到环糊精结构上,并保持了完整的内盐结构。一种方法是以对甲苯磺酰氯做基团转换剂,合成了6-脱氧-甜菜碱基环糊精。一种方法是将甜菜碱基团预先制成潜甜菜碱化合物,然后通过“合成—脱保护”一锅法将甜菜碱基团通过醚键接到环糊精结构上。2.合成了2-O-（2-羟基丙基-氯化三乙胺盐基）-β-环糊精和6-O-（2-羟基丙基-氯化三乙胺盐基）-β-环糊精两种不同取代位置,具有良好水溶性的阳离子环糊精,增强了环糊精的性能,扩大了环糊精的应用范围。3.用毛细管电泳法研究了6-脱氧-甜菜碱基-β-环糊精和6-O-（2-羟基-3-甜菜碱基-丙基）-β-环糊精,2-HB-β-CD,6-HB-β-CD,2-O-HPTEA-β-CD,6-O-HPTEA-β-CD的分子识别行为。发现:1) 2面修饰的环糊精能够在一定程度上扩大环糊精的空腔,使环糊精与客体分子可作用的空间加大,识别能力提高。2)中性修饰的HB-β-CD环糊精由于不带电荷,而中性或者酸性药物存该实验条件下也不带电荷,因此毛细管电泳的分离效果很差。3) HPTEA-β-CD由于带正电荷,和中性或者酸性药物形成包结物后,使包结物也能带上电荷,有利于毛细管电泳的电迁移,所以其对中性或者酸性药物的分离效果都不错。本实验中,HPTEA-β-CD对所选的五种酸性药物都有良好的分离效果。4) 6-脱氧-甜菜碱基环糊精由于功能修饰基团甜菜碱基团与空腔之间的距离较短,造成修饰基团对空腔的封盖,导致环糊精的识别能力降低。6-HBP-β-CD甜菜碱基团与环糊精之间的链长加大,避免了修饰基团与环糊精空腔之间的直接作用,但是甜菜碱基团的内盐结构具有一定的稳定性,需要pH值降低到2.5左右才能减弱内盐结构中的电性作用,使修饰基团的识别作用显现出来。由于甜菜碱基团修饰的位置是在一面上,对环糊精手性环境影响不大,并且中性或者酸性药物在pH=2.5时不带电荷,6-HBP-β-CD对酸性和中性药物没有识别能力。三.两亲环糊精衍生物2-O-（羟丙基-N,N-二甲基-N-十二烷基铵）-β-环糊精的合成及表征1.通过控制反应条件合成了具有良好水溶性的两亲环糊精衍生物2-O-（羟丙基-N,N-二甲基-N-十二烷基铵）-β-环糊精。以反应活性高的对甲苯磺酸酯为中间体,将羟基转化为二甲基胺基,为长链二甲基烷基胺的合成提供了一条新的思路。以小分子醇为相转移催化剂,解决了长链醚化剂水相反应中,溶解度差,易起泡等问题,为长链醚化剂在水柑制备表面活性化合物等方面的应用提供了方法。2.用表面张力法测定了2-HPDMDA-β-CD的临界胶束浓度cmc,该cmc比DTAC的cmc小一个数量级左右。在15℃到35℃之间,cmc随温度的变化不大,在20℃时,2-HPDMDA-β-CD的效能最高。3.用稳态荧光法测定了2-HPDMDA-β-CD在水中的聚集行为,表明2-HPDMDA-β-CD可以提供两种与客体分子作用的空间:一种是环糊精空腔,一种是2-HPDMDA-β-CD的烷基长链形成的疏水聚集体。4.用电导率法验证了cmc,并计算出胶束解离度α,表明大部分的2-HPDMDA-β-CD是以阳离子离子状态存在的。这可能是因为环糊精基团是2-HPDMDA-β-CD的亲水头基,其横截面积比N（CH₃）₃⁺的横截面积大的多,可以为反离子Cl^-提供更多的空间。5.用动态光散射和透射电镜观察了2-HPDMDA-β-CD在水溶液中的聚集状态。发现2-HPDMDA-β-CD在水中主要以两种聚集体形式存在:一种聚集体的水动力学半径不随着2-HPDMDA-β-CD的浓度变化而变化,这可能是由2-HPDMDA-β-CD单体或低聚体形成的水动力学半径;一种聚集体的水动力学半径随着2-HPDMDA-β-CD的浓度的增大。四.两亲型阳离子环糊精衍生物的合成及添加剂对其聚集形态的影响1.以反应活性高的对甲苯磺酸酯为中间体,将羟基转化为二甲基胺基,合成了N,N-二甲基十四胺,N,N-二甲基十六胺,N,N-二甲基十八胺,并进一步合成了具有良好水溶性的两亲阳离子环糊精衍生物系列—2-O-（羟丙基-N,N-二甲基-N-十二烷基铵）-β-环糊精,2-O-（羟丙基-N,N-二甲基-N-十四烷基铵）-β-环糊精,2-O-（羟丙基-N,N-二甲基-N-十六烷基铵）-β-环糊精,2-O-（羟丙基-N,N-二甲基-N-十八烷基铵）-β-环糊精。2.采用动态光散射法和透射电子显微镜法研究了上述两亲型阳离子环糊精衍生物在水中的聚集形态,并研究了添加剂氯化钠,乙醇,水杨酸钠,金刚烷甲酸对上述阳离子环糊精衍生物系列在水中的聚集形态的影响:在阳离子环糊精衍生物的水溶液中,其聚集形态主要取决于烷基长链的长度。随着烷基长链的延长,烷基长链的疏水能力加强,环糊精衍生物的亲油亲水比加大,衍生物的单体或低聚体形成的小聚集体不稳定性增大,导致小聚集体最终消失。氯化钠能够提供反离子Cl^-,结合到环糊精亲水头基上,降低亲水头基水化水的数量,压缩亲水头基的体积,不利于溶液中单体或低聚体的稳定,并且削弱了正电荷的电性排斥,使烷基长链更易接近,从而使聚集体的水动力学半径增大。乙醇可以进入烷基长链形成的疏水部分,能够降低烷基长链间的疏水作用力,使两亲阳离子环糊精衍生物单体或低聚体形成的聚集体可以稳定下来。但随着烷基长链疏水能力的提高,乙醇进入疏水部分的量减少,大部分仍存在于水溶液中,与亲水头基上的水化水竞争,降低了亲水头基的体积,有利于水动力学半径较大的聚集体形成。水杨酸钠能够与两亲分子的环糊精空腔发生包结作用,并和阳离子结构相互作用,降低两亲分子之间的电性排斥,聚集体可以形成较为稳定的结构,使小的聚集体体积增大,但烷基长链的疏水作用达到一定的强度后,亲水头基简单的性质改变并不能影响聚集体的形貌。金刚烷甲酸加入到两亲分子溶液中,会形成结构较为规整的金刚烷甲酸的包结物,并且随着金刚烷甲酸的浓度的升高,包结物浓度增大,结构较为规整的两亲分子数目增多,聚集体的水动力学半径增大。当金刚烷甲酸的浓度超过1mM时,金刚烷甲酸开始进入到烷基长链形成的疏水结构中,引起疏水结构的改变,使聚集体的水动力学半径减少。更多还原

【Abstract】 Cyclodextrins,as functional supermolecular host compound,have attracted more and more attention in simulation design of artificial hosts for their good biocompatibility and modifiable molecular structure.As the largest scale industrial production of cyclodextrins,β-CD has been winning more and more applications and developments for its low price and high performance.However,the inherent defects of naturalβ-CD restrict its practical applications.For instance,the lacks of chromophores and auxochromes would limit the UV-Fluorescence analysis application ofβ-CD in supramolecular chemistry（Host-Guest interaction）.In addition,β-cyclodextrin is lack of effective functional point of enzymes.To increase its Pattern Recognization（PR） ability for an enzyme simulation,theβ-cyclodextrin should be modified to become functionalβ-cyclodextrin derivatives by introducing certain functional groups.Moreover,poor water-solubility also restricts the application ofβ-CD.In order to expending its application,it is necessary to modifyβ-cyclodextrin properly.The main content of the paper showed as follows:1 Series of hydroxylalkyl-β-cyclodextrin supermolecular host compounds:their preparation and application in molecular recognitionA new water-soluble cyclodextrin derivative 6-O-（2-hydroxyibutyl）-β-cyclodextrin （6-HB-β-CD） was prepared.A serie of supermolecular host compounds 6-O-（2-hydroxylpropyl）-β-cyclodextrin（6-HP-β-CD）,2-O-（2-hydroxylbutyl）-β-cycl odextrin（2-HB-β-CD）,2-O-（2-hydroxylpropyl）-β-cyclodextrin（2-HP-β-CD） were also prepared for the purpose of detecting the rules of host-guest interaction.Ultraviolet-visible spectrophotometer was employed to detect the host-guest inclusion phenomena and circulardichroism spectrophotometer was employed to detect the possible structure of host-guest complex.The combination of the two methods could analysis the structure of host-guest complex.And this method is very helpful in understanding the vital process and in the development of new catalytic system.Methyl orange,methyl blue,methyl violet,which have correlated molecular structure were used as the guest probes.The series of cyclodextrin derivatives,which have homologous substituent group on different sides ofβ-cyclodextrin were used as the host compounds.It found that there were several factors affecting the interaction of host-guest,such as size/shape matching,hydrophilic property,hydrophobic property,the steric hindrance.2 Betainyl-β-cyclodextrins:preparation and their application in capillary electrophoresis.Two methods were employed to link the betaine substituent toβ-cyclodextrin with the entire inner-salt structure by stable covalent bonds.One method was that the betaine substituent linked toβ-cyclodextrin directly（mono-6-deoxy-betainyl-β-cyclodextrin） with the intermediate mono-6-O-p-toluenesulfnyl-β-cyclodextrin.The other method was that the betaine was converted to pro-betaine compound and the betaine substituent was linked toβ-cyclodextrin with ether bonds by a "synthesis-deprotection one pot" method（6-O-（2-hydroxyl-3-betainylpropyl）-β-cyclodextrin,6-HBP-β-CD）.Two kinds of water-soluble cationicβ-cyclodextrin derivatives 2-O-（hydroxyl propyltriethylammonia）-β-cyclodextrin（2-O-HPTEA-β-CD）,6-O-（hydroxypropyl triethylammonia）-β-cyclodextrin（6-O-HPTEA-β-CD） were prepared with the intention of producing useful functional models with enhanced performances characteristics.The molecular recognition ability ofβ-CD,2-HP-β-CD,2-HB-β-CD, 6-HB-β-CD,mono-6-deoxy-betainyl-β-cyclodextrin,6-HBP-β-CD,2-O-HPTEA -β-CD,6-O-HPTEA-β-CD was carried out by the separate results of the cappilary electrophoresis.The substituents on the secondary side ofβ-cyclodextrin could enlarge the cavity ofβ-cyclodextrin and accommodate guest molecules with enough space.This could enhance the molecular recognition ability of host compounds. HB-β-CDs with neutral substituents had little selectivity about neutral drugs and acidic drugs in our experiment conditions for there were no charge on hosts or guests.2-O-HPTEA-β-CD,6-O-HPTEA-β-CD had better separate ability about neutral drugs and acidic drugs for they could form inclusion compounds with charge which were propitious to electromigration in capillary electrophoresis.Mono-6-deoxy-betainyl-β-cyclodextrin had poor molecular recognition ability for the betainyl group could cover the cavity of the cyclodextrin derivative because of short distance between betainyl group and cyclodextrin.6-HBP-β-CD could avoid the direct interaction of the betainyl group and the cavity of 6-HBP-β-CD for the chain between betainyl groups with parent cyclodextrin was long enough,pH 2.5 was found to be the most suitable pH for 6-HBP-β-CD about the drug enantiomers.When pH increased,electrovalent interaction of the betainyl group was stable and 6-HBP-β-CD had no selectivity to the drugs.When pH decreased,electrovalent interaction of the betainyl group could be broken and the carboxylate group turned to be carboxyl group, which resulted in a decreased enantioselectivity of 6-HBP-β-CD to the drugs. 6-HBP-β-CD had no selectivity about neutral drugs and acidic drugs for neutral drugs and acidic drugs had no charge under the pH.3 Amphiphilic cyclodextrin derivative 2-O-（hydroxylpropyl-N,N-dimethyl-N-do decylammonio）-β-cyclodextrin:preparation and characterizationA new water-soluble amphiphilic cyclodextrin derivative 2-O-（hydroxyl propyl-N,N-dimethyl-N-dodecylammonio）-β-cyclodextrin（2-HPDMDA-β-CD） was prepared.A useful method was employed to synthesize N,N-dimethylalkylamine with a long phobic chain.An efficient phase-transfer catalyst isopropyl alcohol was employed to resolve the problem of the low yield of 2-HPDMDA-β-CD in aqueous phase.2-HPDMDA-β-CD was found to be a fine surfactant with a smaller critical micelle concentration（cmc）（1.21mM） value than that of dodecyltrimethylammonium chloride.The cmc of 2-HPDMDA-β-CD was relatively stable between 15℃and 35℃.20℃was the temperature at which the highest effectiveness of 2-HPDMA-C12-CD was observed. The results of steady-state fluorescence measurement suggested that 2-HPDMDA-β-CD could perhaps be used as a fine host compound with two functional spaces:one is micelles and the other is the cyclodextrin cavity.The degree of ionization,α,of the micelle suggested that most of 2-HPDMDA-β-CD existed in aqueous solution as cationic ions.This could attributed to that the cross-sectional area of the hydrophilic head was larger than that of N（CH₃）₃⁺ and could accommodate antiparticle Cl^- with enough space.The results of dynamic light scattering and transmission electron microscopy measurement showed that two major aggregates existed in the solution.The aggregates with a smaller size（hydrodynamic radius（R_h） of 2.4 nm） were independent of concentration,which may be attributed to the R_h of a monomer or oligomer of 2-HPDMDA-β-CD.The aggregate with a larger size shows relatively strong concentration dependence.4 Series of amphiphilic cationic cyclodextrin derivatives:preparation and additive effect about their microstructureN,N-dimethyltetrodecylamine,N,N-dimethylhexadecylamine,N,N-dimethyl octadecylamine was prepared with alkyl p-toluenesulfonate which had high reactivity. Then,series of amphiphilic cationic cyclodextrin derivatives 2-o-（hydroxypropyl-N, N-dimethyl-N-dodecylammonio）-β-cyclodextrin（2-HPDMDA-β-CD）,2-o-（hydroxyl propyl-N,N-dimethyl-N-tetrodecylammonio）-β-cyclodextrin（2-HPDMTA-β-CD）, 2-o-（hydroxypropyl-N,N-dimethyl-N-Hexadecylammonio）-β-cyclodextrin（2-HPDM HA-β-CD）,2-o-（hydroxypropyl-N,N-dimethyl-N-octadecyl ammonio）-β-cyciodextrin （2-HPDMOA-β-CD） were prepared for the first time.Dynamic light scattering and transmission electron microscopy were employed to observe the aggregation of above series of the amphiphilic cyclodextrin derivatives in aqueous solution.The additive effect,such as NaCl,ethanol,sodium salicylate, 1-adamantanecarboxylic acid about the aggregation was also observed.The aggregation form of the amphiphilic cationic cyclodextrin dereivatives in aqueous solution related to the length of the hydrophobic alkyl chain.The hydrophobic ability of alkyl chains would enhance when the alkyl chain prolonged, and the hydrophile-lipophile balance number（HLB） of the amphiphilic cyclodextrin derivatives would decrease.Then,the aggregation stability of a monomer or oligomer would decrease and disappear in aqueous solution.When NaCl was the additive,counterion Cl^- could combine to the hydrophilic head and decrease the amount of the water of hydration on the hydrophilic head.This could result in that the volume of the hydrophilic head in water became small and the stability of a monomer or oligomer of 2-HPDMDA-β-CD aggregation would decrease. Counterion Cl^- could also decrease the electrovalent repulsion of the hydrophilic head and the long alkyl chains aggregated easily to form large aggregation.Ethanol could enter the hydrophobic parts of the aggregation and decrease the hydrophobic interaction.This could make a monomer or oligomer of 2-HPDMDA-β-CD aggregation stable in aqueous solution.The amount of ethanol in the hydrophobic parts of the aggregation would decrease when the hydrophobic ability of the long alkyl chain enhanced.Ethanol in aqueous solution would compete with the water of hydration on the hydrophilic head and decrease the volume of the hydrophilic head.This could result in the formation of large aggregation with large hydrodynamic radius.The amount of ethanol in aqueous solution could also increase when the ethanol concentration increased.This could also result in the formation of large aggregation.Sodium salicylate could not enter into the hydrophobic parts of the aggregation for its better solubility in water.Sodium salicylate could enter into the cavity of the amphiphilic cyclodextrin derivative to form inclusion compounds with electrovalent interaction and decrease the electrovalent repulsion of the hydrophilic head.This could make the aggregation of the amphiphilic cyclodextrin derivatives stable in water. However,sodium salicylate could not effect the aggregation of the amphiphilic cyclodextrin derivatives when the hydrophilic property of the long alkyl chain enhanced to a certain extent.1-adamantanecarboxylic acid could enter into the cavity of the amphiphilic cylcodextrin dereivativs and form stable inclusion compounds with simple surfactant structure when 1-adamantanecarboxylic acid added into the aqueous solution.This resulted in that there were three kinds of aggregations in the aqueous solution.When the concentration of 1-adamantanecarboxylic acid increased,the concentration of inclusion compounds with simple surfactant structure increased and the hydrodynamic radius of aggregations increased,1-adamantanecarboxylic acid began to enter into the hydrophobic parts of the aggregation when its concentration was larger than 1mM. This could change the structure of the hydrophobic parts of the aggregation and decrease the hydrodynamic radius of the aggregations.更多还原