含有Oxazolidin-2-one的伪,可以折叠成贝塔曲的带螺旋
Claudia Tomasini1, Gianluigi Luppi, Magda Monari
1Dipartimento di Chimica G. Ciamician, Alma Mater Studiorum Università di Bologna, Via Selmi 2, 40126 Bologna, Italy. claudia.tomasini@unibo.it
Journal of the American Chemical Society
|February 16, 2006
概括
合成和分析了具有特定氧化丁 (Oxd) 部分的寡合体. B组的寡合体显示出形成有序β-曲带螺旋结构的能力,这是一种3(10) -螺旋子类型.
科学领域:
- 酸的化学结构
- 超分子化学 超分子化学
- 有机合成 有机合成
背景情况:
- 合成了含有4-carboxy-5-methyloxazolidin-2-one (Oxd) 部分的寡合体.
- 研究这些寡合物的折叠成有序结构对于理解它们的特性至关重要.
研究的目的:
- 合成和分析三组含有Oxd部分的寡合物.
- 为了确定这些寡合体是否可以折叠成有序结构.
- 为了确定折叠的寡合体所采用的特定的二次结构.
主要方法:
- 三个寡合体集的合成:Boc- ((L-Ala-L-Oxd) ((n) -OR,Boc- ((L-Ala-D-Oxd) ((n) -OR,以及Boc- ((Aib-L-Oxd) ((n) -OR.
- 使用红外吸收,核磁共振和循环二极化 (CD) 光谱分析偏好形状的分析.
- 评估稳定效应,包括Oxd部分刚性,分子内H键和C=O...H-N H键.
主要成果:
- 确定了三种稳定作用:刚性Oxd部分 (转变形状),Oxd C=O...H-(alpha) C H-键,以及1 $\leftarrow$ 4分子内C=O...H-N H-键.
- 只有B组寡合体[Boc-(L-Ala-D-Oxd) ((n) -OR) ]满足了所有三个稳定要求.
- CD光谱分析显示,B组寡合体采用β-曲丝带螺旋二次结构,是一种3(10) -螺旋子类型.
结论:
- B组的寡合体表现出一种倾向于有序的结构形成.
- 鉴定到的二次结构是一个β-曲的丝带螺旋,一种特定类型的3(10) -螺旋.
- 这项研究阐明了含有Oxd的寡合体的结构偏好.
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