Expedient synthesis of two structurally close tetrasaccharides corresponding to the O-antigens of Escherichia coli O127 and Salmonella enterica O13

Two structurally close tetrasaccharides corresponding to the O-antigens of Escherichia coli O127 and Salmonella enterica O13 have been synthesized using a ‘unichemo’ approach and minimum number of reaction steps. The yields of all glycosylation steps were excellent with a high stereochemical outcome. A common synthetic strategy has been adopted for the simultaneous synthesis of two tetrasaccharides.