Complete Solid State13C NMR Chemical Shift Assignments for α-D-Glucose, α-D-Glucose-H2O and β-D-Glucose

Abstract
NMR spectra of crystalline .alpha.-D-glucose .cntdot. H2O (1), .alpha.-D-glucose (2), and .beta.-D-glucose (3) were examined by 13C cross polarization magic angle spinning (CPMAS) methods. Each of the 3 forms of glucose exhibited a distinctly different spectrum. Chemical interconversion of 2 and 3 as well as the in situ dehydration of 1 during the course of the CPMAS NMR experiment was monitored in the 13C spectra. Samples of 1, 2 and 3 specifically enriched at C-1 and C-6 with 13C yielded 13C spectra in which the resonances corresponding to the adjacent C-2 and C-5 carbons were not visible due to strong homonuclear 13C dipolar interactions with the high abundance label. Spectra of these analogs as well as the C-2 and C-3 labeled materials provided the complete 13C chemical shift assignments of crystalline 1, 2 and 3. A comparison of the solid state and solution 13C spectra revealed substantial resonance shift for each of the 3 structures examined.