Synthesis of Lipooligosaccharide Antigens from Mycobacteria

• Author / Creator

  Bai, Bing

• Lipooligosaccharides (LOSs) are one of the three major classes of glycolipids produced by mycobacteria. Over 15 LOSs have been isolated and characterized in the past three decades. However, there are only a small number of studies that have focused on the synthesis of LOSs molecules. In this thesis, I have developed a synthetic route to oligosaccharide fragments of LOS III from Mycobacterium gastri. To achieve our purpose, eight different building blocks were designed and synthesized. The L-xylopyranosides were prepared via stannanylidene acetal, a key intermediate for the selective protection of the hydroxyl groups. Two synthesized D-glucopyranosides were then coupled into an α,α-trehalose in 49% yield, while the coupling between the 3,6-dideoxy sugar alkene and terminal olefin failed to give any desired product. In the synthesis of the oligosaccharide target, a key intermediate pentasaccharide was prepared using a 2+1+2 strategy. Upon obtaining this pentasaccharide, two oligosaccharides, a nonasaccharide and an ocatasaccharide, were synthesized as key advanced intermediates to the LOS target.

• Subjects / Keywords

  • Mycobacteria
  • Trehalose
  • Xylose
  • Lipooligosaccharide
  • 3,6-dideoxy

• Graduation date

  Fall 2014

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/R3Q23R986

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.