A 1H- and 13C-n.m.r. spectroscopic analysis of six pseudohexoses

Conformation, dynamics, solvation and relative stabilities of selected β-hexopyranoses in water: a molecular dynamics study with the gromos 45A4 force field

“…104,241,251,[293][294][295]333,353 On the other hand, the limited impact of intramolecular hydrogen-bonding between the 4-OH and 6-OH groups in water on this conformational distribution has been clearly evidenced experimentally by (i) examining the influence of the solvent polarity on this distribution; 101,102,131,152,157,180,189,190,305,351 (ii) analyzing the correlation between the rotamer populations of the x and v 6 dihedral angles 96 (see above); and (ii) investigating hexopyranose analogs and model compounds lacking specific potential hydrogen-bonding groups. 92,101,102,104,131,144,152,189,190,305,351,[354][355][356][357] Many of these studies also hint toward a negligible effect of H 6 !O 5 hydrogen-bonding.…”

Structure conversions of cellulose IIII crystal models in solution state: a molecular dynamics study

“…Obviously, the profiles reflect the structural environment where the surface residues exist. The sa profile at 300 K has a large population of hydroxymethyl groups in gg conformations at 300 K, and this increases at 370 K. The x angle distributions of an isolated glucose in solution mostly consisted of gg and gt conformations (Nishida et al 1984;Ohrui et al 1985;Bock et al 1988). This suggests the hydroxymethyl groups on the (0 1 0) crystal surface were virtually in a similar environment to an isolated residue in solution.…”

A combined nuclear magnetic resonance and molecular dynamics study of the two structural motifs for mixed-linkage β-glucans: methyl β-cellobioside and methyl β-laminarabioside

“…39 These results are also in good agreement with average reported experimental values for b-D-glucose. 54,55 The only significant deviation from free monomer behavior occurs for x 2 in methyl b-cellobioside where the gg rotamer is populated for approximately 91% of the time. This reduction of conformational freedom is probably a consequence of the position of the hydroxymethyl group next to the glycosidic linkage in methyl b-cellobioside.…”