NUCLEAR-MAGNETIC-RESONANCE SPECTROSCOPIC ANALYSIS OF THE SELECTIVE COMPLEXATION OF THE CIS AND TRANS ISOMERS OF PHENYLALANYLPROLINE BY BETA-CYCLODEXTRIN

被引：55

作者：

LIN, MF ^{[1
]}

JAYAWICKRAMA, DA ^{[1
]}

ROSE, RA ^{[1
]}

DELVSCIO, JA ^{[1
]}

LARIVE, CK ^{[1
]}

机构：

[1] UNIV KANSAS,DEPT CHEM,LAWRENCE,KS 66045

来源：

ANALYTICA CHIMICA ACTA | 1995年 / 307卷 / 2-3期

基金：

美国国家科学基金会;

关键词：

COMPLEXES; CYCLODEXTRINS; NUCLEAR MAGNETIC RESONANCE SPECTROMETRY; PHENYLALANINE; PROLINE;

D O I：

10.1016/0003-2670(95)00006-L

中图分类号：

O65 [分析化学];

学科分类号：

070302 ; 081704 ;

摘要：

Nuclear magnetic resonance (NMR) spectroscopy was used to examine the effect of beta-cyclodextrin inclusion complex formation on the cis-trans equilibrium constant of phenylalanylproline, Phe-Pro. The pK(a) values of the ionizable groups of Phe-Pro have been determined in solutions containing equimolar ratios of the peptide and beta-cyclodextrin. Comparison of these values with acidity constants of the free peptide suggest a hydrogen bond between beta-cyclodextrin and the cis isomer carboxylate group that is not observed for the trans isomer. Diffusion coefficients for the cis and trans isomers of Phe-Pro in aqueous and in beta-cyclodextrin solution have been measured using pulsed-field gradient NMR spectroscopy. Diffusion ordered NMR spectroscopy (DOSY) was used to selectively measure the diffusion coefficients of beta-cyclodextrin and both isomers of Phe-Pro. The preferential formation of the beta-cyclodextrin inclusion complex with cis Phe-Pro was observed in the DOSY spectra and formation constants for this complex calculated.

引用

页码：449 / 457

页数：9

共 31 条

[1] H-1-NMR EVIDENCE FOR 3 INTERCONVERTING FORMS OF STAPHYLOCOCCAL NUCLEASE - EFFECTS OF MUTATIONS AND SOLUTION CONDITIONS ON THEIR DISTRIBUTION [J].