Conformational analysis of methyl β-cellobioside by ROESY NMR spectroscopy and MD simulations in combination with the CROSREL method

Abstract

Methyl β-cellobioside has been studied extensively by molecular dynamics (MD) simulations in water and by ROESY NMR spectroscopy in order to establish its solution structure. The MD simulations were started with four significantly different minimal energy conformations. The MD trajectories were analysed with respect to interproton distances and mobility, in order to find models for application in the analysis of NMR data. The ROESY spectra were analysed by using the CROSREL method, which allows quantitative analysis of ROESY spectra through correction for the offset dependence and incorporation of HOHAHA transfer estimates. These results were compared with data obtained from an initial rate analysis of the ROESY data and with the MD data. It is concluded that methyl beta-cellobioside in aqueous solution is in the same extended conformation that is also found in the solid state.