Nuclear Magnetic Resonance Spectroscopy. Carbon-13 Spectra of Some Common Oligosaccharides

The applicability of carbon-1 3 magnetic resonance spectroscopy to the study of oligosaccharides is demonstrated. The spectra of four disaccharides are discussed and interpreted, and the methods used in peak assignments are explained. The dependences of carbon chemical shifts and carbohydrate conformations upon pH are discussed and, contrary to earlier reports, it is shown that no large changes in the anomeric mixture of glucose are observed in strong base. The spectra of four fully acetylated sugars are presented and partially assigned. Finally, a brief investigation of the carbon-13 spectra of amylose and cellulose acetate is presented, and the potential of this method of studying polysaccharide conformations emphasized.