用DNP增强的固态NMR进行自然同位素丰度的有机分子的完整 (13) C/(15) N分配
Katharina Märker1,2, Morgane Pingret1,2, Jean-Marie Mouesca1,2
1Univ. Grenoble Alpes, INAC , F-38000 Grenoble, France.
Journal of the American Chemical Society
|October 21, 2015
概括
这项研究引入了新的核磁共振 (NMR) 相关实验,用于在自然同位素丰度下在有机分子中赋予碳-13和-15共振. 这种进步简化了NMR结晶学,并使固态NMR的精确距离测量成为可能.
科学领域:
- 固态核磁共振 (NMR) 光谱
- 晶体学
- 有机化学
背景情况:
- 自然同位素丰度 (NA) 的有机分子的NMR结晶学通常需要比较实验和计算的NMR化学转移.
- 在没有计算辅助的情况下,有限的质子 (1H) 分辨率和分配碳-13 (13C) 和-15 (15N) 共振的挑战阻碍了广泛的应用.
- 目前的方法通常依赖于基于结构的化学转移计算,限制了de novo赋值.
研究的目的:
- 克服在自然同位素丰度下对有机分子的NMR共振的限制.
- 提出一种使用相关谱的全新13C和15N共振分配的新方法.
- 证明这种方法对简化1H分配和实现固态NMR距离测量的实用性.
主要方法:
- 使用动态核极化 (DNP) 增强核磁共振 (NMR) 光谱.
- 进行13C-13C和15N-13C相关性实验.
- 应用这些方法,在不对称的单元细胞中分配一个自组装的2'-脱氧氨酸衍生物的共振.
主要成果:
- 在自然同位素丰度 (NA) 中实现了全新的13C和15N共振赋值.
- 证明了DNP增强的13C-13C和15N-13C相关性实验的有效性.
- 展示了这种分配策略简化了随后的1H分配,对于固态NMR距离测量至关重要.
结论:
- 基于DNP增强的15N-13C和13C相关性谱的新分配策略被介绍.
- 这种方法克服了对13C和15N分配的计算化学转移计算的需求.
- 该方法通过促进1H分配和使固态NMR的距离测量显著推进了NMR结晶学.
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