Hydrolysis of the Phosphonamidate Bond in Phosphono Dipeptide Analogues— the Influence of the Nature of the N-Terminal Functional Group
作者:Artur Mucha、Jolanta Grembecka、Tomasz Cierpicki、Paweł Kafarski
DOI:10.1002/ejoc.200300469
日期:2003.12
pseudodipeptides, designed as transition state analogue inhibitors of leucine aminopeptidase, revealed unexpected instability in aqueous solutions of pH values varying from acidic up to highly basic. This reaction has been studied in some detail by means of NMR spectroscopy and it was found that the phosphonamidate stability depended strongly on the solution pH, relying on the protonation state of two crucial functional
设计为亮氨酸氨肽酶的过渡态类似物抑制剂的膦酰胺假二肽在 pH 值从酸性到强碱性不等的水溶液中表现出出乎意料的不稳定性。已通过 NMR 光谱对该反应进行了一些详细研究,发现膦酰胺酸酯的稳定性强烈依赖于溶液的 pH 值,依赖于分子的两个关键官能团——膦酰胺酸酯和氨基部分的质子化状态。发生快速 PN 键分解需要游离 N 端氨基部分的质子化;N-保护的衍生物明显更稳定。已经提出并讨论了膦酰胺键断裂的机制。观察到的未封闭 P-N 肽的不稳定性可能是它们作为氨肽酶抑制剂的实际应用受到实质性限制的原因。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)