通过连贯的2DIR光谱学探测的aib寡中的3(10) 螺旋二次结构的出现
Hiroaki Maekawa1, Fernando Formaggio, Claudio Toniolo
1Department of Chemistry, University of California at Irvine, Irvine, California 92697-2025, USA.
Journal of the American Chemical Society
|May 1, 2008
概括
二维红外 (2D IR) 光谱学揭示了结构是如何形成的. 较短的呈现出明显的模式,而较长的,如五,开始形成3~10) 螺旋结构.
科学领域:
- 频谱学是一种光谱学.
- 生物物理学的生物物理.
- 计算化学的计算化学
背景情况:
- 酸中二次结构的形成对它们的功能至关重要.
- 二维红外 (2D IR) 光谱是研究分子结构和动态的强大工具.
- 了解体构造对于药物设计和材料科学至关重要.
研究的目的:
- 用二维红外光谱学研究中二次结构的出现.
- 为了检查二维红外光谱模式如何随着链长度的增加而演变.
- 为了将实验2DIR数据与形状的计算模拟相关联.
主要方法:
- 在CDCl3.3中测量Cα甲基化同型 (Z-(Aib) n-OtBu,n=3,5,8,10) 的二维红外光谱.
- 对胺-I区域的光谱图案进行分析,以评估体构造和尺寸灵敏度.
- 振动刺激模型模拟用于解释实验性的2D红外光谱和二面角分布.
主要成果:
- 2D红外光谱对形状,乱和大小都很敏感.
- 与较长的 (五,八,十) 相比,三的光谱模式显著不同.
- 对于较长的,光谱特征趋同,表明稳定的二次结构的形成.
结论:
- 3(10) 螺旋状的二次结构开始在五水平上形成.
- 三体表现出形状异质性,表明种群超出单个β转.
- 2D红外光谱学有效地探测二次结构形成的早期阶段.
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