Graduate School of Science and Engineering, Yamagata University, Yonezawa, Yamagata 992-8510, Japan.
Graduate School of Organic Materials Science, Yamagata University, Yonezawa, Yamagata 992-8510, Japan.
J Org Chem. 2023 Feb 3;88(3):1319-1326. doi: 10.1021/acs.joc.2c01342. Epub 2023 Jan 19.
Previously, we developed a method for the detection of unprotected amino groups based on their reversible reaction with -hydroxyphthalimide (NHPI) to form intensely colored products, which can be useful when conducting solid-phase peptide synthesis. Here, we describe a structure-activity relationship study of NHPI derivatives to identify the derivative best suited for this method using a spectrophotometer toward the estimation of chemical yields. We found that the products resulting from the reaction of the derivative with an unprotected amino group were only intensely colored if the structure of the derivative incorporated an NHPI framework. We also prepared five peptides, including those containing -methyl and D-amino acid, and Pro residues, using our reversible detection method to detect unprotected amino groups. The mechanism of the detection reaction was also studied by the structural analysis of the NHPI () and diisopropylamine complex and concluded to entail salt formation between the -hydroxy group and amine.
此前，我们开发了一种基于 unprotected amino groups 与 -hydroxyphthalimide (NHPI) 可逆反应生成强烈显色产物的检测方法，该方法在固相肽合成中很有用。在这里，我们描述了 NHPI 衍生物的构效关系研究，以使用分光光度计确定最适合该方法的衍生物，从而估算化学产率。我们发现，只有当衍生物的结构中包含 NHPI 框架时，衍生物与 unprotected amino group 的反应产物才具有强烈的颜色。我们还使用我们的可逆检测方法制备了包括 -methyl 和 D-amino acid 以及 Pro 残基的 5 种肽，以检测 unprotected amino groups。还通过对 NHPI () 和二异丙胺配合物的结构分析研究了检测反应的机制，并得出结论，涉及 -羟基和胺之间的盐形成。
