Syntheses are described of two trisaccharides, 2-(p-trifluoroacetamidophenyl)ethyl O-(b-D-xylopyranosyl)-(1->2)-O-(a-D-mannopyranosyl)-(1->3)-a-D-mannopyranoside and 2-(p-trifluoroacetamidophenyl)ethyl O-(a-D-mannopyranosyl)-(1->3)-[O-(b-D-xylopyranosyl)-(1->2)]-a-D-mannopyranoside, and of the tetrasaccharide 2-(p-trifluoroacetamidophenyl)ethyl O-(b-D-xylopyranosyl)-(1->2)-O-(a-D-mannopyranosyl)-(1->3)-[O-(b-D-xylopyranosyl)-(1->2)]-a-D-mannopyranoside. These correspond to parts of the repeating unit I of the major structure of the capsular polysaccharide of Cryptococcus neoformans sero-group A. [on SciFinder (R)]