阿扎-β3-cyclopeptides:一种新的控制化的方法
Clémence Mocquet1, Arnaud Salaün, Paul Claudon
1ICMV and CSM, UMR CNRS 6226, Université de Rennes I, 35042 Rennes Cedex, France.
Journal of the American Chemical Society
|October 8, 2009
概括
研究人员使用水或氨基酸合成了新的宏循环. 这些稳定的结构展示了动态的选,首次控制了较大的分子中的性.
科学领域:
- 有机化学 有机化学
- 超分子化学 超分子化学
- 化学晶体学 化学晶体学
背景情况:
- 亚扎-贝塔(3) - 基宏循环是复杂的分子,在各种领域都有潜在的应用.
- 控制较大的循环分子中的性,特别是涉及原子的分子,一直是化学中长期存在的挑战.
研究的目的:
- 合成新型16和24个成员的aza-beta(3)-peptidic宏循环,其中包括α-hydrazinoacid或β-aminoacid残留物.
- 研究这些宏观循环的结构性质和稳定性.
- 探索这些系统中动态enantioselection的潜力.
主要方法:
- 合成阿扎-贝塔(3) - 基宏循环.
- 使用NH化学转移分析,NH灭绝和可变温度核磁共振 (VT-NMR) 实验进行形态分析.
- 用X射线衍射进行结构确定.
主要成果:
- 成功合成含有α-氨酸或β-α-氨基酸的16个和24个成员的宏循环.
- 在广泛的温度范围内 (223-413 K) 证明了宏循环的构造稳定性.
- 确定一个不间断的内部键网络和不对称中心的综合学排列.
- 观测动态的enantioselection,其中光学纯净的残留物作为 conformational锁,以控制绝对配置在多个中心.
结论:
- 合成的宏观循环表现出了显著的形状稳定性和独特的结构组织.
- 这项研究提供了在涉及多个倾向于发生金字塔倒置的立体中心的宏观循环中动态反选择的第一个例子.
- 这些发现为控制较大的循环系统中的化性提供了新的策略,克服了与较小循环相关的先前限制.
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