TY - JOUR A1 - Mackie, I.D. A1 - Röhrling, J. A1 - Gould, R.O. A1 - Pauli, Jutta A1 - Jäger, Christian A1 - Walkinshaw, M. A1 - Potthast, A. A1 - Rosenau, Th. A1 - Kosma, P. T1 - Crystal and molecular structure of methyl 4-O-methyl-beta-D-glucopyranosyl-(1->4)-beta-D-glucopyranoside JF - Carbohydrate research N2 - The cellulose model compound methyl 4-O-methyl-?-Image-glucopyranosyl-(1?4)-?-Image-glucopyranoside (6) was synthesised in high overall yield from methyl ?-Image-cellobioside. The compound was crystallised from methanol to give colourless prisms, and the crystal structure was determined. The monoclinic space group is P21 with Z=2 and unit cell parameters a=6.6060 (13), b=14.074 (3), c=9.3180 (19) Å, ?=108.95(3)°. The structure was solved by direct methods and refined to R=0.0286 for 2528 reflections. Both glucopyranoses occur in the 4C1 chair conformation with endocyclic bond angles in the range of standard values. The relative orientation of both units described by the interglycosidic torsional angles [? (O-5?---C-1?---O-4---C-4) -89.1°, phi (C-1?---O-4---C-4---C-5) -152.0°] is responsible for the very flat shape of the molecule and is similar to those found in other cellodextrins. Different rotamers at the exocyclic hydroxymethyl group for both units are present. The hydroxymethyl group of the terminal glucose moiety displays a gauche–trans orientation, whereas the side chain of the reducing unit occurs in a gauche–gauche conformation. The solid state 13C NMR spectrum of compound 6 exhibits all 14 carbon resonances. By using different cross polarisation times, the resonances of the two methyl groups and C-6 carbons can easily be distinguished. Distinct differences of the C-1 and C-4 chemical shifts in the solid and liquid states are found. KW - Crystal structure KW - Cellulose KW - Methyl cellobioside KW - Solid state NMR PY - 2002 DO - https://doi.org/10.1016/S0008-6215(01)00299-3 SN - 0008-6215 SN - 1873-426X VL - 337 IS - 2 SP - 161 EP - 166 PB - Elsevier CY - Amsterdam AN - OPUS4-11023 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -