Synthese von 2-methylalanin-peptiden, die pH-Abhängiggkeit ihrer 13C-NMR-spektren und eine neue methode zur auswertung über CS-diagramme
作者:Dieter Leibfritz、Erhard Haupt、Norbert Dubischar、Heinrich Lachmann、Raymond Oekonomopulos、Günther Jung
DOI:10.1016/0040-4020(82)85164-8
日期:1982.1
The uncommon amino-acid 2-methylalanine (α-aminoisobutyric acid, Aib) was investigated by 13C-NMR. The chemical shifts of amino- or carboxy-protected derivatives of Aib and of protected oligopeptides are discussed with respect to neighbouring groups and amino acids. The pH-dependence of the 13C-NMR spectra of Aib, Aib-Ala, Ala-Aib, Aib-Ala-Aib and Aib-Ala-Aib-Ala-Aib was studied. Using these examples
通过13 C-NMR研究了不常见的氨基酸2-甲基丙氨酸(α-氨基异丁酸,Aib)。关于相邻基团和氨基酸,讨论了Aib的氨基或羧基保护的衍生物和受保护的寡肽的化学位移。研究了Aib,Aib-Ala,Ala-Aib,Aib-Ala-Aib和Aib-Ala-Aib-Ala-Aib的13 C-NMR光谱的pH依赖性。使用这些示例,首次展示了一种新的有利方法,用于评估NMR滴定曲线,该方法使用了所谓的化学位移图(CS图)。