stereochemicak Effects in Mass Spectromery 15.——Thermospray Mass spectra of Methyl Glycosides of Monosaccharides

In present work, the thermospray mass spectra of methyl glycosides of six hexsoses and four pentoses have been measured. The relative abundances of fragment ions, (M+NH_4-H_2O)~+, (M+NH_4-2H_2O)~+ or (M+NH_4-H_2O-NH_3)~+ of epimers of these glycosides are quite different from each other (see Table 1). These phenomena have been discussed on a stereochemieal view.