N-磷酰化叉肽结构与NMR波谱

THE STUDY ON THE STRUCTURAL CHARACTERISTICS OF N-PHOSPHORYLATED BRANCHED PEPTIDE

测定了N 磷酰化叉肽 ( 2 5)在溶液中的NMR谱 .发现它们具有非对映异位 ,分子无规卷曲及氢键相互作用 .波谱分析表明 ,磷酰基的参与 ,主要影响其结合部位的氨基酸 .由于肽平面的生成及分子内、分子间氢键影响的改变 ,致使叉肽中支链的Dipp Ala磷酰基与 β位羰基的相对位置发生变化 .磷酰基与N Cα 基团仍处于反式位置 。

The structural characteristics of N phosphorylated branched peptides 2 5 in solution have been studied by NMR. Diastereotopic phenomena, the interaction of hydrogen bonds and no regular secondary structures have been observed. It has been shown that participation of phosphoryl group only affects amino acid, which was bond on the phosphoryl group. Due to the formation of peptide planes and the increase of the effect of hydrogen bond between inter or intra molecules, the position of P=O group relating with C\-β=O group in compounds 2 5 was changed from trans into gauche conformation as compared with that in Dipp Ala of compound 1. The phosphoryl group was still lain on trans position with N C\-α group. It suggests that there is not any polar groups on the side chain of the amino acid. These structural characteristics will provide some evidence for their studies.