Identification ofO-Methyl Substituted Glycopyranoses and Their Methyl glycosides by hmbc,1H and13C NMR Chemical Shift Increments and the3J(13C,1H) Coupling Constant About the Ch3O-Ch Bond.

Abstract The substitution site of partially O-methylated glycopyranoses is identified by HBMC. Their 1H and 13 C NMR chemical shifts are evaluated by considering chemical shift increments. The 3J(13 C, 1H) coupling constants are evaluated. Interesting applications of chemical shift increments are illustrated.