Synthesis of oligosaccharides related to the capsular polysaccharide of Neisseria meningitidis serotype A

In order to find suitable stable vaccine candidates against Neisseria meningitidis group A, several structures related to the capsular polysaccharide have been synthesised. The first part of the thesis describes the synthesis of C-phosphonate analogues starting from glucose. The key step is a Mitsunobu coupling of a methyl C-phosphonate monomer to the 6-hydroxyl group of a 2-acetamido mannose derivative. Contained within this work is a description of an improved synthesis of 2-azido-2-deoxy-D-mannopyranose. The second part outlines the synthesis of structural elements present in the native capsular polysaccharide of Neisseria meningitidis serotype A including different acetylation and phosphorylation patterns. The final chapter describes an improved synthesis of the Lewis b hexasaccharide needed for purification of and interaction studies with the Helicobacter pylori adhesin BabA