Conformation of <i>N</i><sup>α</sup>-Substituted Hydrazino Acetamides in CDCl<sub>3</sub>, the Precious Help of the Analysis of Δδ between Amidic Hydrogens, and Correlation to the Conformation of Aza-β<sup>3</sup>-peptides
作者:Arnaud Salaün、Annaïck Favre、Barbara Le Grel、Michel Potel、Philippe Le Grel
DOI:10.1021/jo051887q
日期:2006.1.1
adopted by hydrazino acetamides 1a and 1b as model compounds for aza-β3-peptides. In this manner, it was possible to show that the amidic group of these compounds acts as a H-bond donor and interacts with two different H-bond acceptors. We concluded that the hydrazinoturn, a specific bifurcated H-bond system observed in the solid state, is also the preferred conformation of hydrazino acetamides 1a and 1b
我们研究了氯仿溶液中一系列伯酰胺的构象。将经典的NMR工具(例如稀释实验,DMSO和2D-NOESY的影响)与X射线衍射相结合,并分析了双键mid质子之间化学位移Δδ的差异。本研究中为了理解由肼基乙酰胺采用的构象是写给1A和1B作为模型化合物为氮杂- β 3-肽。以这种方式,有可能表明这些化合物的酰胺基充当氢键供体并与两个不同的氢键受体相互作用。我们得出的结论是,肼苯二酚,一种在固态下观察到的特定的分叉H键系统,也是溶液中肼基乙酰胺1a和1b的优选构象。我们的研究结果表明,与所述短距离相互作用Ñ α -氮的孤对电子不仅稳定C8 pseudocycle但也可能有助于氮杂- β的折叠处理3 -肽。鉴于此,它可以解释为什么氮杂β 3 -肽发展比较不同的氢键网络,其等量β 3-肽类似物。我们的工作与肼基肽作为β肽概念的扩展的最新兴趣保持一致。