Synthesis of p -Trifluoroacetamidophenyl 3- O -[2-Acetamido-2-Deoxy-3- O -(α- L -Fucopyranosyl)-β- D -Glucopyranosyl]-β- D -Galactopyranoside and of p -Trifluoracetamidophenyl 3- O -[2-Acetamido-2-Deoxy-3- O (α- L -Fucopyranosyl)-4- O (β- D -Galactopyranosyl)-β- D -Glucopyranosyl]-β-