黄瓜[n]uril的形成是通过逐步生长的循环-寡合化过程进行的
Wei-Hao Huang1, Peter Y Zavalij, Lyle Isaacs
1Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA.
Journal of the American Chemical Society
|June 6, 2008
概括
葡萄糖烯的寡合体和nor-seco-cucurbit[n]urils在有限的甲中形成. 环状五聚和六聚寡合物结合客体,为更大的分子扩展腔,揭示了甲形成中的循环-寡合化阶段增长机制.
科学领域:
- 超分子化学 超分子化学
- 有机合成 有机合成
- 晶体工程公司 晶体工程公司
背景情况:
- 库库尔比特[n]urils (CB[n]) 是宏环化合物,通常以1:2的糖和甲比率合成.
- 不完整的凝结反应产生CB[n]类型的混合物和线性或循环性糖氨的寡合物.
研究的目的:
- 为了分离和表征在亚静态度甲条件下形成的非循环糖利寡合体.
- 研究这些寡合体的结合性和结构特征.
- 为了阐明甲[n]uril形成的机制.
主要方法:
- 染色学净化糖瑞寡合物 (二聚体到六聚体).
- 溶液状态的表征 (NMR,MS).
- 用于结构确定的X射线晶体学.
- 客人绑定研究.
- 产品重新提交的实验.
主要成果:
- 隔离和结构特征的C形甘瑞寡合体 (二元六合体).
- 环状五合体和六合体寡合体表现出类似于CB的客体结合能力[6],其扩展的腔体容纳了更大的客体.
- 产品重新提交显示了在CB[n]形成期间对特定环形状的偏好.
- 为CB[n]合成提出了一个全面的机制方案.
结论:
- 包括非环 pentamers 和 hexamers 在内的 glycoluril oligomers 可以被分离和表征.
- 这些寡合物具有独特的结合性质,证明了腔体大小的适应性.
- CB[n]和相关化合物的形成通过一步增长的循环-寡合化途径进行.
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