作者:Thomas Hoeg-Jensen、Arne Holm、Hilmer Sorensen
DOI:10.1055/s-1996-4437
日期:1996.3
A dipeptide thioamide model system, Boc-Leu-Ï[CSNH]-MetOMe, was used for evaluating the preservation of amino acid stereochemistry during thioacylation utilizing amino monothio acids. The LL and DL peptide diastereomers were separated by use of high performance capillary electrophoresis (micellar electrokinetic capillary chromatography). The described thioacylation method combines monothio acids with coupling reagents of the PyBOP-family for generating active thiono esters with low-levels of enantiomerisation (<2%). The best results in terms of stereochemical preservation and yield were obtained with PyNOP, a 6-nitro analog of PyBOP. The successful activation of thiobenzoic acid with all four coupling reagents extended the scope of the method to include aryl monothio acids.
利用二肽硫代酰胺模型体系 Boc-Leu-Ï[CSNH]-MetOMe 评估了利用氨基单硫酸进行硫代酰化时氨基酸立体化学的保留情况。利用高效毛细管电泳(胶束电动毛细管色谱法)对 LL 和 DL 肽非对映异构体进行了分离。所述硫代酰化方法将单硫代酸与 PyBOP 家族的偶联试剂结合在一起,可生成对映体化程度较低(<2%)的活性硫代酯。使用 PyBOP 的 6-硝基类似物 PyNOP 可获得最佳的立体化学保存效果和产率。用所有四种偶联试剂成功活化了硫代苯甲酸,从而将该方法的应用范围扩展到了芳基一硫代酸。