High resolution 1H NMR structural studies of sucrose octaacetate in supercritical carbon dioxide

High pressure (HP), high resolution (HR), proton nuclear magnetic resonance (H-1 NMR) spectroscopy has been utilized for the first time to investigate the solution structure of a carbohydrate based system, sucrose octaacetate (SOA), in supercritical CO2. The studies indicate that the average solution state conformation of the alpha-(D)-Glucopyranosyl ring of SOA in scCO(2) medium is consistent with the C-4(1) chair form, while the beta-(D)-fructofuranosyl ring adopts an envelope conformation. The investigations also suggest that scCO(2) is a promising medium to study the solution structure and conformation of acetylated sugar systems. Spectral manifestations of a specific interaction between the acetate methyl protons and CO2 molecules are also presented.