Efficient synthesis of a 6-deoxytalose tetrasaccharide related to the antigenic O-polysaccharide produced by Aggregatibacter actinomycetemcomitans serotype c

Concise synthesis of a 6-deoxy-alpha-L-talose tetrasaccharide, 6-deoxy-alpha-L-Talp-(1 -> 3)-6-deoxy-alpha-L-Talp-(1 -> 2)-6-deoxy-alpha-L-Talp-(1 -> 3)-6-deoxy-alpha-L-Talp, the dimer of the disaccharide repeating unit of the OPS from Aggregatibacter actinomycetemcomitans serotype c, has been accomplished through suitable protecting group manipulations and stereoselective glycosylation starting from commercially available L-rhamnose. The target oligosaccharide in the form of its p-methoxyphenyl glycoside is suitable for further glycoconjugate formation via selective cleavage of this group. (C) 2010 Elsevier Ltd. All rights reserved.