Determination of both linkage position and anomeric configuration in underivatized glucopyranosyl disaccharides by electrospray mass spectrometry

Negative‐ion electrospray mass spectrometry was used to determine directly both glycosidic linkage position and anomeric configuration in the complete glucopyranosyl disaccharide series without the need for derivatization or tandem mass analysis. A series of empirical criteria were developed which first differentiate between the linkage positions and then the anomeric configurations using selected diagnostic peaks and their relative intensities. The use of standard mass spectral library searching methods for structural analysis was also investigated.