Laboratory of Molecular Science and Engineering, Åbo Akademi University, 20500, Turku, Finland.
Institute of Biocomputation & Physics of Complex Systems (BIFI), University of Zaragoza, 50009, Zaragoza, Spain.
Chemistry. 2022 Jun 15;28(34):e202200499. doi: 10.1002/chem.202200499. Epub 2022 May 11.
Acyl group migration affects the synthesis, isolation, manipulation and purification of all acylated organic compounds containing free hydroxyl groups, in particular carbohydrates. While several isolated studies on the migration phenomenon in different buffers have been reported, comprehensive insights into the overall migration process in different monosaccharides under similar conditions have been lacking. Here, we have studied the acyl migration in different monosaccharides using five different acyl groups by a combination of experimental, kinetic and theoretical tools. The results show that the anomeric configuration in the monosaccharide has a major influence on the migration rate, together with the relative configurations of the other hydroxyl groups and the nature of the migrating acyl group. Full mechanistic model, based on computations, demonstrates that the acyl migration proceeds through an anionic stepwise mechanism with linear dependence on the [OH ] and the pK of the hydroxyl group toward which the acyl group is migrating.
酰基迁移影响所有含有游离羟基的酰化有机化合物，特别是碳水化合物的合成、分离、操作和纯化。虽然已经有关于不同缓冲液中迁移现象的一些孤立研究，但缺乏对类似条件下不同单糖中整体迁移过程的全面了解。在这里，我们使用五种不同的酰基，通过实验、动力学和理论工具的组合，研究了不同单糖中的酰基迁移。结果表明，单糖中的端基构型对迁移速率有很大影响，同时还有其他羟基的相对构型和迁移酰基的性质。基于计算的完整机理模型表明，酰基迁移通过阴离子逐步机理进行，与 [OH ] 和向其迁移的羟基的 pK 值呈线性关系。
