Synthesis of di- and tetrasaccharide containing 6-deoxytalose from the O-antigenic polysaccharide of B. pseudomallei strain 304b

Synthesis of the disaccharide beta-D-Glup-(1 -> 3)-6-deoxy-alpha-L-Talp II, and its dimer III from the O-antigenic polysaccharide of Burkholderia pseudomallei strain 304b, were achieved through assembly of suitably synthesized building blocks, 4-methoxylphenyl 6-deoxy-2,4-di-O-benzoyl-Ct-L-talopyranoside (7), 3-O-allyl-2,4,6-tri-O-benzoyl-alpha,beta-D-glucopyranosyl trichloroacetimidate (8) and 2,3,4,6-tetra-0-benzoyl-alpha,beta-D-glucopyranosyl trichloroacetimidate (11). The total yield of III from 4-methoxylphenyl 2,3-O-isoprpylidene-alpha-L-rhamnopyranoside (1) was 18%. (C) 2009 Jian Jun Zhang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.