应用化学 ›› 1989, Vol. 0 ›› Issue (3): 21-25.

• 研究论文 • 上一篇    下一篇

蛋氨酸稀土配合物构象的13C NMR研究

任吉民, 裴奉奎, 王文韵   

  1. 中国科学院长春应用化学研究所
  • 收稿日期:1988-07-01 修回日期:1988-10-04 出版日期:1989-06-10 发布日期:1989-06-10
  • 基金资助:
    国家自然科学基金

13C-NMR STUDY ON CONFORMATION OF LANTHANIDE COMPLEXES WITH METHIONINE

Ren Jimin, Pei Fengkui, Wang Wenyun   

  1. Changchun Institute of Applied Chemistry, Academia Sinica
  • Received:1988-07-01 Revised:1988-10-04 Published:1989-06-10 Online:1989-06-10

摘要: 本文测量了在7种不同稀土离子(La3+、Pr3+、Nd3+、Dy3+、Ho3+、Er3+和Tm3+)的水溶液中蛋氨酸13C稀土诱导位移。利用稀土诱导位移对蛋氨酸稀土配合物构象的模拟结果表明,蛋氨酸通过离子化的羧基与稀土离子配位,Ln3+-O长度为2.7A在配合物中,蛋氨酸以伸展状态存在,Co-Cα-Cβ-Cγ和Cα-Cβ-Cγ-S成反式构象,Cβ-Cγ-S-Cδ成旁式构象。根据稀土诱导位移方法建立的构象模型符合1H邻位质子偶合常数和13C顺磁弛豫速率的结果。

关键词: 13C, NMR, 蛋氦酸, 构象, 稀土诱导位移

Abstract: Lanthanide-induced shifts have been measured for 13C nuclei of methionine in thepresence of seven lanthanide cations (La, P1, Nd, Dy, Ho,Er, Tm) in aqueous solution.The simulation for conformation of lanthanide complexes with methionine shows that theligand is coordinated to lanthanide ion through oxygen atoms of carboxyl group and thebend length of Ln-O is 2.7Å. In the complexes,methionine is in extended state,the favor- able conformation of Cο-Cα-Cβ-Cγ-S and Cα-Cβ-Cγ-S is in trans, while that of Cβ-Cγ-S-Cδin gauche. The conformation established for methionine complex by lanthanide-inducedshift method is in agreement with the results of vicinyl proton coupling constants and 13Cparamagnetic relaxation rate determinations.

Key words: 13C NMR, Methionine, Lanthanide-induced shift, Conformation