摘要
利用紫外-可见吸收和荧光发射光谱,结合非线性最小二乘法拟合曲线以及分子力学(MM2)模拟系统地研究了手性分子N-[4-(1-芘基)]丁酰-D/L-苯丙氨酸(PDP和PLP,总称PPs)与β-环糊精(-βCD)、2-位硒桥联双-βCD(2-SeCD)和2-位碲桥联双-βCD(2-TeCD)的包结能力大小及这3个环糊精对PPs手性识别能力的差异和识别机理.研究结果表明,PPs不能与单疏水空腔的-βCD形成很好的包结复合物,与具有较长桥联链的2-TeCD结合能力最强.2-TeCD与PDP和PLP的结合常数分别为2.33×104和6.07×103L/mol,对PPs的手性识别比达到KD/KL=3.84,高于2-SeCD(KD/KL=2.61).用MM2模拟得出了PPs与这两个双环糊精形成复合物的三维结构:PPs的绝大部分位于双环糊精两个空腔之间,但是在这两个复合物中,苯环与芘环所成的二面角不同.此外,PPs与这两个双环糊精作用时均存在明显的氢键相互作用,且2-TeCD强于2-SeCD.
The binding ability and chiral discrimination of β-cyclodextrin （β-CD）, 2,2＇-diseleno-bridged β- cyclodextrins （ 2-SeCD ） and 2,2 ＇-ditelluro-bridged β-cyclodextrins （ 2-TeCD ） with PPs were investigated in aqueous solution by using UV-Vis and fluorescence spectroscopy as well as MM2 calculation. The stability constants of complexes were obtained by using least-square curve fitting. From the results of UV-Vis and fluorescence spectroscopy, it was shown that β-CD could not form inclusion complexation with PPs while 2-SeCD and 2-TeCD could. The binding ability between 2-TeCD and PDP was higher（Ka = 2.33 × 10^4 L/mol） than that of 2-SeCD/PDP（Ka = 3.03 × 10^3 L/mol）. Meanwhile, the high chiral discrimination of PPs was also performed in binding with 2-TeCD（KD/KL = 3.84）and 2-SeCD（KD/KL = 2.61 ）. Furthermore, the MM2 calculation illustrates that PPs were located between the two cavities of 2-SeCD or 2-TeCD, however, the dihedral angle between phenyl ring and pyrene ring was different from each other when they were included in two bis-cyclodextrins. Meanwhile, MM2 also demonstrates that the intermolecular hydrogen bonding interaction in 2-TeCD/PPs complex was relative stronger than that in 2-SeCD/PPs.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2006年第5期920-924,共5页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:20373017和20473028)
国家重点基础研究发展规划项目(批准号:G2000078102)
长江学者创新团队发展计划项目(批准号:IRT0422)资助
