"亚齐多效应"对亚齐多普罗林的形状的影响
Louis-Sebastian Sonntag1, Sabine Schweizer, Christian Ochsenfeld
1Department of Chemistry, University of Basel, St. Johanns-Ring 19, CH-4056 Basel, Switzerland.
Journal of the American Chemical Society
|November 9, 2006
概括
亚齐多效应影响亚齐多衍生物的形状,有利于特定的环形状. 这影响了胺稳定性和循环,其效果与的 gauche 效应相当.
科学领域:
- 计算化学的计算化学
- 有机化学 有机化学
- 结构生物学 结构生物学
背景情况:
- 在某些化学结构中, gauche 效应描述了对 gauche 结构的偏好,而不是对 anti 结构的偏好.
- 阿兹多普罗林 (Azp) 衍生物是氨基酸类型,在化工和药物设计中具有潜在的应用.
- 了解Azp的构造性行为对于预测的结构和功能至关重要.
研究的目的:
- 为了研究"azido gauche效应"对 (4R) -和 (4S) -azidoproline衍生物的形状的影响.
- 通过理论和实验来确定这种效应对胺基适合器比率和酸环化趋势的影响.
- 为了比较azido gauche效应的强度与已知效应的强度.
主要方法:
- 对 (4R) - 和 (4S) - 亚齐多普罗林衍生物的实验性检查.
- 使用ab initio计算进行理论分析.
- 罗利丁环和胺键的形态分析.
- 确定s-trans:s-cis 胺基对应器比率.
主要成果:
- 亚酸效应决定了 (4R) Azp衍生物的C(4) -exo构造,通过n-->pi相互作用稳定了s-trans amide构造器.
- (4S) Azp衍生品采用C(4) -endo形态,缺乏这种稳定相互作用,并表现出较低的s-trans:s-cis比率.
- 计算表明,亚酸效应的强度与酸效应相当,能量差异为5-13kJmol{-1},有利于亚乙衍生物中的酸构造.
结论:
- (4R) Azp衍生品由于亚酸效应,与 (4S) Azp衍生品相比,对s-trans amide适配器的偏好更高.
- 形状偏好影响含有Azp的的倾向形成具有全cis胺键的循环结构.
- 阿齐多效应是阿齐多普罗林衍生物的重要形状决定因素,对结构和合成有影响.
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