【作者】 孙聪善；

【导师】 张毅民；

【作者基本信息】 天津大学 ， 化学工艺， 2007， 硕士

【摘要】 β-环糊精特有的疏水空腔结构能够选择性包结各种客体分子,形成稳定的包结物,从而达到改善客体分子的水溶性、稳定性的目的,近年来,被广泛的应用于医药、分析、食品、环境等多个领域。主体与客体小分子形成的包结物的结构研究,是我们认识这种分子包结和分子组装现象的理论基础,有关这方面的研究一直受到普遍关注。本文采用β-环糊精作为主体分子,选取邻氨基苯甲酸、间氨基苯甲酸、对氨基苯甲酸以及萘普生作为客体。通过X-射线粉末衍射、傅立叶红外光谱、1H核磁共振谱、圆二色谱、单晶X-射线衍射以及分子模拟的方法对所形成的包结物结构进行了研究。本文将主客体物质按照不同的比例溶解到水溶液,或者乙醇-水的混合溶液中,在70℃下搅拌混合2h,缓慢降至室温,用微孔滤膜过滤反应产物,取过滤后的清液室温下缓慢挥发溶剂,得到所需要的包结物。将包结物取出,置于真空干燥箱内干燥至恒重,然后对其进行结构表征,同时利用分子模拟的方法探讨主客体的包结方式。结果表明,邻氨基苯甲酸与β-环糊精形成了1:1的包结物,苯环被包结进了环糊精空腔,氨基与羧基都朝向环糊精的大口端,分子动力学模拟显示,主客体分子的质心距离在2 ?左右波动;间氨基苯甲酸与β-环糊精形成了1:1的包结物,苯环被包结进了环糊精空腔,氨基朝向环糊精的大口端,羧基朝向环糊精的小口端,分子动力学模拟显示,主客体分子的质心距离在1.2 ?左右波动;对氨基苯甲酸与β-环糊精形成了2:2的包结物,苯环被包结进了环糊精空腔,氨基朝向环糊精的大口端,羧基朝向环糊精的小口端,分子动力学模拟显示,主客体分子的质心距离在0.6 ?左右波动,分子模拟的结果与晶体数据相符;萘普生与β-环糊精形成了1:1的包结物,萘环被包结进了环糊精空腔,分子力学模拟数据表明羧基朝向环糊精的大口端是包结物的稳定构象,分子动力学模拟显示,主客体分子的质心距离在4.5 ?左右波动;氨基苯甲酸的三种异构体与β-环糊精形成的包结物中,分子模拟的结果都表明,氨基和羧基都与β-环糊精的羟基形成了氢键,分子动力学模拟结果说明,在三种异构体中,对氨基苯甲酸进入环糊精空腔的深度最大,最小的是邻氨基苯甲酸。更多还原

【Abstract】 Due to the unique structure with hydrophobic central cavity,β-cyclodextrin can selectively bind different guest molecules to form inclusion complexes in order to improve solubility, stability of guest molecules. Thus,β-cyclodextrin has been widely used in many different fields, such as pharmaceutics, analytics, food and environment, etc. The structure research of host-guest inclusion complex is the basic problem of molecular inclusion phenomena and supramolecular assembling, the study about this area is focused on all the time.In this paper,β-cyclodextrin was used as the host molecule and the o-aminobenzoic acid, m-aminobenzoic acid and p-aminobenzoic acid were used as the guest molecules. X-ray powder diffractometry, Fourier transform infrared, 1H nuclear magnetic resonance, circular dichroism, x-ray single crystal diffractometer and molecular simulation method were used to study the inclusion complex structure. The host and guest molecules with different molar ratio were dissolved in water or ethanol-water solvent, and agitated for 2 hours under 70℃, then cooled to room temperature, filtered with membrane filter. The products were stored under room temperature to volatilize the solvent, the solid inclusion complexes were gained. The products were put into vacuum dryer, dried till constant weight. The structures of inclusion complexes were studied, and the inclusion modes of the host-guest complexes were discussed by molecular simulation method.The results showed that: the inclusion complex of o-aminobenzoic acid andβ-cyclodextrin was made with the molar ratio of 1:1, the benzene ring was included into the cyclodextrin cavity, the amido and carboxyl pointed to the big end of cyclodextrin both, molecular dynamic simulation result indicated that the host-guest centroid distance was about 2 ?; the inclusion complex of m-aminobenzoic acid andβ-cyclodextrin was made with the molar ratio of 1:1, the benzene ring was included into the cyclodextrin cavity, the amido pointed to the big end of cyclodextrin and the carboxyl pointed to the small end, molecular dynamic simulation result indicated that the host-guest centroid distance was about 1.2 ?; the inclusion complex of p-aminobenzoic acid andβ-cyclodextrin was made with the molar ratio of 2:2, the benzene ring was included into the cyclodextrin cavity, the amido pointed to the big end of cyclodextrin and the carboxyl pointed to the small end, molecular dynamic simulation result indicated that the host-guest centroid distance was about 0.6 ?, the molecular simulation result was in accordance with the crystalline data; naproxen and β-cyclodextrin inclusion complex were synthesized with the molar ratio of 1:1, naphthaline ring was included into the cyclodextrin cavity, molecular simulation result indicated that the state which carboxyl pointed to the big end was the stable structure, molecular dynamic simulation showed that the host-guest centroid distance was about 4.5 ?; the hydrogen bond was observed by molecular silulation in the inclusion complexes of three isomers of aminobenzoic acid withβ-cyclodextrin, and the p-aminobenzoic acid was buried into cyclodextrin cavity deeply, the o-aminobenzoic acid was opposite.更多还原