Conformational Studies of cyclo(L-Phe-L-Pro-Gly-L-Pro)2 by 1H-and 13C-Nuclear magnetic Resonance Spectroscopy, and Its Enantioface-differentiating Ability.
作者:Takashi ISHIZU、Ayumi FUJII、Shunsaku NOGUCHI
DOI:10.1248/cpb.41.235
日期:——
Analyses of the 1H- and 13C-nuclear magnetic resonance (1H- and 13C-NMR) spectra of the cyclooctapeptide cyclo (L-Phe-L-Pro-Gly-L-Pro)2 (3) in CDCl3 with the aid of the C-H correlated spectroscopy (C-H COSY) two-dimensional NMR spectrum (Fig. 2) suggested that two kinds of C2-symmetric conformation with all trans and cis-trans-trans-trans forms coexist. When 0.5 eq of CsSCN or 1 eq of D- and L-PheOMe
借助CDCl3对环八肽环(L-Phe-L-Pro-Gly-L-Pro)2(3)的1H和13C核磁共振光谱(1H和13C-NMR)进行分析CH相关光谱法(CH COSY)的二维NMR光谱(图2)表明,两种具有全部反式和顺式-反式-反式-反式形式的C2对称构象共存。将0.5 eq的CsSCN或1 eq的D-和L-PheOMe.HCl(D / L比= 1/2)添加到环八肽(3)在CDCl3中的溶液中时,1H-和13C-NMR光谱(图3)表明仅存在一种C 2对称构象(全反式),这是与CsSCN或D-和L-PheOMe.HCl形成复合物的结果。环八肽(3或4)与D-和L-PheOMe.HCl的配合物的13C-NMR光谱显示D-PheOMe.HCl和L-PheOMe.HCl的每个碳原子都有独立的共振。