earticle

영어

The unique trisaccharide repeating unit, [→3)-α-D-Rhap-(1→2)-α-D-Manp3CMe-(1→3)-α -L-Rhap-(1→], of the O-polysaccharide of the lipopolysaccharide from Danish Helicobacter pylori strains has been synthesized. Key steps include the coupling of three monosaccharide moieties by glycosylations employing the 2'-carboxybenzylglycoside method and stereoselective epoxide ring opening to prepare the novel branched sugar, 3-C-methyl-D-mannose, which has not been found in Nature before. furthermore, the synthesis of a hexasaccharide and a nonasaccharide were successfully achieved by dimerization or trimerization of the repeating units of trisaccharide employing the 2'-carboxybenzyl glycoside method.