ISSN:
1573-5001
Keywords:
1D transient NOE
;
Metropolis Monte Carlo simulations
;
Flexibility of glycosidic linkages
;
Maltose
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
Notes:
Summary One-dimensional transient NOE build-up curves were measured for the synthetic disaccharide α-d-Fuc-(1→4)-β-d-GlcNAc 1 utilizing Gaussian shaped pulses. Simulated build-up curves from Metropolis Monte Carlo simulations were compared to the experimental data. Disaccharide 1 is structurally related to methyl β-d-maltoside in that it also contains an α-(1→4) linkage, and it has the same configuration of groups around the glycosidic linkage. Analysis of NOEs in methyl β-d-maltoside is restricted to those observed upon selective excitation of H1′ because of severe spectral overlap. The situation is different in 1 where 1H-NMR signals are well separated. Several interglycosidic NOEs were observed. The corresponding build-up curves allowed an accurate determination of the conformational preferences at the glycosidic linkage in 1. Comparison of experimental and theoretical NOE build-up curves showed clearly that rigid minimum-energy models cannot account for the experimental data. The best fit of experimental NOE build-up curves was obtained with theoretical curves from a 2×106 step Metropolis Monte Carlo simulation with the temperature parameter set at 1000 K. Finally, it was observed that only the interglycosidic NOE H5′/H6-pro-S significantly depends upon varying conformation distributions at the α-(1→4)-glycosidic linkage, induced by choosing different temperature parameters for the Metropolis Monte Carlo simulations.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00176007
Permalink
