Building Biologics by Chemical Synthesis: Practical Preparation of Di- and Triantennary <i>N</i>‑Linked Glycoconjugates

A unified strategy for the syntheses of bi- and triantennary fully sialylated <i>N</i>-glycans is described. The synthesis capitalizes on a global glycosylation strategy that delivers the desired undeca- and tetradecasaccharide in excellent yields. Finally, conjugation of the glycan to PSMA oligopeptide is described.