The convergent synthesis of the Lewis A (Le(a)) tandem repeat is described. The Le(a) tandem repeat is a carbohydrate ligand for a mannose binding protein that shows potent inhibitory activity against carcinoma growth. The Le(a) unit, {beta-D-Gal-(1 -> 3)-[alpha-L-Fuc-(1 -> 4)]-beta-D-GlcNAc}, was synthesized by stereoselective nitrile-assisted beta-galactosylation with the phenyl 3-O-allyl-2,4,6-tri-O-benzyl-1-thio-beta-galactoside, and ether-assisted alpha-fucosylation with fucosyl (N-phenyl) trifluoroacetimidate. This common Le(a) unit was easily converted to an acceptor and donor in high yields, and the stereoselective assembly of the hexasaccharide and dodecasaccharide as the Le(a) tandem repeat framework was achieved by 2-trichloroacetamido-assisted beta-glycosylation and the (N-phenyl) trifluoroacetimidate method.