肽合成中的反应机理。第1部分。2-甲基-5（4H）-恶唑酮在气相和弱极性介质中与水和氨反应活性的半定量特征。

Reaction mechanisms in peptide synthesis. Part 1. Semiquantitative characteristics of the reactivity of 2-methyl-5(4H)-oxazolone with water and ammonia in the gas phase and weakly polar media.

作者信息

Ciarkowski J, Chen F M, Benoiton N L

机构信息

Department of Biochemistry, Faculty of Medicine, University of Ottawa, Ont., Canada.

出版信息

J Comput Aided Mol Des. 1991 Dec;5(6):585-97. doi: 10.1007/BF00135316.

DOI:10.1007/BF00135316

PMID:1818092

Abstract

2,4-Dialkyl-5(4H)-oxazolones are well-recognized intermediates in some aminolysis reactions in peptide synthesis. Using the MOPAC molecular orbital programs, detailed geometric and energetic characteristics of the elementary reaction pathways for the additions of water and ammonia to 2-methyl-5(4H)-oxazolone have been determined at the AM1 level. The results demonstrate that the additions must be parsed into a two-step mechanism involving formation of the alpha-hydroxyimine followed by tautomerization to the parent N-acetylamino acid or amide.

摘要

2,4-二烷基-5（4H）-恶唑酮是肽合成中某些氨解反应中公认的中间体。使用MOPAC分子轨道程序，在AM1水平上确定了水和氨加成到2-甲基-5（4H）-恶唑酮的基本反应途径的详细几何和能量特征。结果表明，加成反应必须解析为两步机制，包括α-羟基亚胺的形成，然后互变异构为母体N-乙酰氨基酸或酰胺。