Syntheses are described of the tetrasaccharide 2-(4-trifluoroacetamidophenyl)ethyl O-(b-D-galactopyranosyl)-(1->2)-O-(D-glycero-a-D-manno-heptopyranosyl)-(1->2)-O-(L-glycero-a-D-manno-heptopyranosyl)-(1->3)-L-glycero-a-D-manno-heptopyranoside and the three trisaccharides 2-(4-trifluoroacetamidophenyl)ethyl O-(L-glycero-a-D-manno-heptopyranosyl)-(1->2)-O-(L-glycero-a-D-manno-heptopyranosyl)-(1->3)-L-glycero-a-D-manno-heptopyranoside, 2-(4-trifluoroacetamidophenyl)ethyl O-(b-D-glucopyranosyl)-(1->4)-O-(b-D-glucopyranosyl)-(1->4)-L-glycero-a-D-mannopyranoside, and 2-(4-trifluoroacetamidophenyl)ethyl O-(b-D-galactopyranosyl)-(1->4)-O-(b-D-glucopyranosyl)-(1->4)-L-glycero-a-D-manno-heptopyranoside, corresponding to structures found in the lipooligosaccharides of Haemophilus influenzae. [on SciFinder (R)]