Mechanistic Evaluation of Bioorthogonal Decaging with <i>trans</i>-Cyclooctene: The Effect of Fluorine Substituents on Aryl Azide Reactivity and Decaging from the 1,2,3-Triazoline
作者:Siddharth S. Matikonda、Jessica M. Fairhall、Franziska Fiedler、Suchaya Sanhajariya、Robert A. J. Tucker、Sarah Hook、Anna L. Garden、Allan B. Gamble
DOI:10.1021/acs.bioconjchem.7b00665
日期:2018.2.21
subsequent release from the 1,2,3-triazoline are reported. As the number of fluorine substituents on the PABC linker increases from one to four, the rate of cycloaddition increases by almost one order of magnitude. Using a combination of fluorescence, 1H/19F NMR, and computational experiments, we have been able to determine how substituents on the PABC ring can influence the degradation rates and also the product
生物正交前药的激活/减少策略必须是选择性的,快速的,并在激活后将其从掩蔽组中释放出来。反式-环辛烯(TCO)与一系列氟取代的叠氮基-PABC自消化间隔基在两种模型药物之间发生的1,3-偶极环加成速率以及随后从1,2,3-三唑啉的释放是报告。随着PABC接头上氟取代基的数量从一增加到四,环加成速率增加了几乎一个数量级。使用荧光的组合,1 H / 19通过NMR和计算实验,我们已经能够确定PABC环上的取代基如何影响降解速率以及1,2,3-三唑啉的产物分布。我们还能够确定这些取代基如何影响亚胺水解的速率以及生成的苯胺的1,6-自消灭的降解速率。NMR和计算研究表明,芳环上的氟取代基降低了通过双原子氮的挤出将三唑啉转化为亚胺或氮丙啶中间体所需的过渡态能量,而在四氟取代的芳环的情况下,则是亚胺水解和1,6-自焚是限速的。这些知识进一步增强了对影响三唑啉稳定性的因素的理解,