Expeditious Synthesis of Bacterial Glycoconjugates

S1.2 Bacterial glycan synthesis
Location (hall): 
Start/end time: 
Monday, July 1, 2019 - 11:15 to 11:45
Speaker reference: 

Suvarn S. Kulkarni1

1Indian Institute of Technology Bombay, Mumbai, India

Bacterial glycoconjugates are comprised of rare D and L deoxy amino sugars, which are not present on the human cell surface.[1] This peculiar structural difference allows discrimination between the pathogen and the host cell and offers avenues for target-specific drug discovery and carbohydrate-based vaccine development.[2]  However, they cannot be isolated with sufficient purity in acceptable amounts, and therefore chemical synthesis is a crucial step toward the development of these products.  We recently established short and convenient methodologies for the synthesis of orthogonally protected bacterial D and L-deoxy amino hexopyranoside  and glycosamine building blocks starting from cheaply available D-mannose and L-rhamnose.[3-5]  The one-pot protocols rely on highly regioselective nucleophilic displacements of triflates. These procedures have been applied to the synthesis of various bacterial glycoconjugates.[3-10] (Figure 1) as well as metabolic oligosaccharide engineering for selective detection of bacteria.[8]

Figure 1. Representative examples of bacterial and archaeal glycans synthesized using the methodology

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