叶绿素和加密-E的纳入复合物的动力学:证据表明一种强烈异构的范德瓦尔斯债券
J Lang1, J J Dechter, M Effemey
1Division of Physical Chemistry, Stockholm University, S-106 91 Stockholm, Sweden.
Journal of the American Chemical Society
|August 9, 2001
概括
这项研究表明,甲分子在密码-E宿主腔内没有显著的移动. 范德瓦尔斯纳入复合体作为单个分子实体,由NMR交换和放松研究证实.
科学领域:
- 超分子化学 超分子化学
- 物理化学 物理化学
- 核磁共振 (NMR) 光谱学 核磁共振 (NMR) 光谱学
背景情况:
- 范德瓦尔斯的包容复合体涉及宿主与客人的相互作用.
- 了解宿主内部的客分子动态对于宿主-客化学是至关重要的.
- 克里普托芬-E与小分子 (如甲) 形成了包含性复合体.
研究的目的:
- 为了研究在加密-E宿主中的运动动态.
- 为了确定复杂溶液和散装溶液之间甲交换的动力学.
- 分析宿主腔内的客分子的内部运动.
主要方法:
- 质子核过度干扰效应 (NOE) 光谱用于交换研究 (EXSY).
- 用Lipari-Szabo无模型方法分析的碳-13放松测量结果.
- 修改了布洛赫方程,以解释化学交换过程.
主要成果:
- 甲在散装溶液和加密-E复合物之间进行化学交换.
- 分析表明,在加密-E腔内没有显著的内部运动.
- 加密-E-chloroform复合物表现为一个单一的,刚性分子单元.
结论:
- 范德瓦尔斯含有加密-E和的纳入复合体展示了受限制的客人运动.
- 核磁共振研究证实了该复合物的稳定性和客分子的不运动性.
- 这一发现对具有特定分子识别特性的主机-客户系统的设计有影响.
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