实验和计算证据表明,在高一代三胺树状体宿主中,客人容量发生逆转
Jongdoo Lim1, Giovanni M Pavan, Onofrio Annunziata
1Department of Chemistry, Texas Christian University, Fort Worth, Texas 76129, USA.
Journal of the American Chemical Society
|January 14, 2012
概括
高一代的三胺树枝体显示出令人惊的客体容量变化. 分子模拟显示,水透与容量相关,为树枝状细胞的行为提供了新的理解.
科学领域:
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
- 计算化学计算化学
背景情况:
- 体是高度分支的大分子,具有独特的特性.
- 了解树枝状体的宿主-客体化学反应对于它们的应用至关重要.
- 氨酸树状体为分子识别提供了一个多功能平台.
研究的目的:
- 为了合成和表征高一代三胺树状体.
- 以pyrene和camptothecin作为模型客来研究这些树突体的宿主-客化学.
- 阐明树枝状分子结构,溶剂相互作用和客体封装容量之间的关系.
主要方法:
- 合成和特征的三树状分子,直到第九代.
- 实验测定使用pyrene和camptothecin的客体封装容量.
- 在明确溶剂中进行分子动力学模拟,以分析内部结构和水透.
- 分析辐射分布函数以识别结构指纹.
主要成果:
- 奇数一代的三树枝体在第7代之前表现出增加的客体容量,随后在第9代出现下降.
- 分子动力学模拟揭示了树枝状分子内部的水分子透模式.
- 实验测量客人容量与计算确定内部含水量之间建立了线性相关性.
结论:
- 这项研究揭示了高一代三胺树状体客人容量的非单调趋势.
- 内部水分子分布作为树突体客体容量的预测指标.
- 这项工作提供了对结构属性关系的基本见解,这些结构属性关系控制着树突体宿主-客互动.
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