Date of Award
Doctor of Philosophy (PhD)
Roger A. Laine
Certain linkage positions in oligosaccharides can be discerned by collision-activated dissociation mass spectrometry (MS-CID-MS), rationalized by molecular modeling. The first part of this dissertation shows that linkage-specific daughter ion spectra of synthetic amino-sugar containing oligosaccharides can be obtained from several alkylated derivatives such as sodiated, potassiated, ammoniated and lithiated derivatives. Methylated derivatives of the synthetic oligosaccharides give more useful linkage discernment product-ions, including a 3-linkage specific ion. A novel approach of relating daughter ion to parent ion ratios and collision energy is described and is predictive of linkage position in the first set of six oligosaccharides used. In the second part, a set of trisaccharides differing only in linkage position was synthesized by enzyme assistance, reducing the time and labor. For development of tandem mass spectral methods of direct linkage determination in oligosaccharides, a set of trisaccharides differing only in one structural parameter, in this case position of linkage to the reducing-end hexose, were required. Finally, the linkage positions of four novel synthetic trisaccharides were studied using low energy collision-induced-dissociation tandem mass spectrometry (FAB-MS-CID-MS) and molecular modeling. These results confirmed that the FAB-MS-CID-MS combined with molecular modeling can be used to identify the sugar linkage positions in neutral sugars as well as aminosugar-containing oligosaccharides.
Yoon, Eunsun Yoo, "Structure of Synthetic Oligosaccharides by Tandem Mass Spectrometry." (1991). LSU Historical Dissertations and Theses. 5287.