Kinetic characterization of a slow chemical exchange between two sites in N,N-dimethylacetylamide by CEST NMR spectroscopy  

作　　者：Lixia Wang Jikun Li Junfeng Xiang Jie Cui Yalin Tang 

机构地区：[1]Beijing National Laboratory for Molecular Sciences(BNLMS),Center for Molecular Sciences,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190,China [2]University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Chinese Chemical Letters》2022年第9期4335-4338,共4页中国化学快报（英文版）

基　　金：supported under the National Natural Science Foundation of China(Nos.22077123 and 21977099)。

摘　　要：Nuclear magnetic resonance(NMR)spectroscopy has provided many powerful tools for the study of dynamic processes.Among the reported methods,chemical exchange saturation transfer(CEST)is more suitable for systems with slow exchange rates,and there will be promising in the detection and dynamic mechanism of metastable substances.It has been widely used in magnetic resonance imaging(MRI),however whether it is applicable in the field of chemical kinetics needs more examples.Here we studied,as a proof of concept,the kinetics of the slow chemical exchange between the two N-methyl protons of N,N-dimethylacetylamide(DMA),exploiting QUantifying Exchange using Z-spectrum(QUEZS)and QUantifying Exchange using Saturation Time(QUEST)methods.It turned out that both of QUEZS and QUEST could give the corresponding exchange rates,showcasing the capability of this method to provide accurate kinetic data under a range of temperatures.Our results clearly demonstrated the reliability of CEST-based techniques as a tool for dynamic kinetics by NMR.

关 键 词：Chemical exchange saturation transfer(CEST) Chemical exchange N N-Dimethylacetylamid Bloch-Mc Connell equation Dynamic kinetics 

分 类 号：O657.2[理学—分析化学] O643.1[理学—化学]