阿尔干的螺旋形状在一个疏水性洞穴和中
Laurent Trembleau1, Julius Rebek
1Skaggs Institute for Chemical Biology and Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
概括
表面活性剂中的基链在合成受体内采用螺旋形状,取代它们通常的延长形状. 这种螺旋结构是分子识别的首选,尽管引入了应变.
科学领域:
- 超分子化学 超分子化学
- 有机化学 有机化学
- 物理化学 物理化学
背景情况:
- 基通常在溶液中采用延伸形状,以最大限度地减少硬质障碍并最大限度地增加表面积.
- 疏水性相互作用在水性环境中的分子识别和自我组装中起着至关重要的作用.
- 链的折叠可以减少疏水性暴露,但引入不利的左边相互作用.
研究的目的:
- 研究表面活性剂中基链在与合成受体结合时的结构偏好.
- 了解合成受体和表面活性剂分子之间的分子识别背后的驱动力.
- 为了确定螺旋形状是否比延伸形状更优先地被识别.
主要方法:
- 一种专门设计用于结合链的合成受体的合成.
- 用光谱和计算分析来确定结合的基链的结构.
- 热力学测量以量化结合亲和力和能量贡献.
主要成果:
- 表面活性基链在合成受体内复合时采用螺旋形状.
- 与扩展形状相比,受体对螺旋基形状的结合亲和力更高.
- 引入2-3kcal/mol的应变能量以达到螺旋形状,但它在能量上有利于结合.
结论:
- 分子识别可以克服内在的形状偏好,在这个特定的受体内偏好螺旋基.
- 有效填充空间和有效埋葬疏水表面是观察到的分子识别的关键驱动因素.
- 合成受体可以被设计为识别和稳定柔性分子的非原生构造.
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