Total Synthesis of Conjugation‐Ready Tetrasaccharide Repeating Units of Pseudomonas Aeruginosa (Lányi) O11

Herein, we report the first total synthesis of the conjugation‐ready tetrasaccharide repeating units of Pseudomonas aeruginosa (Lányi) O11. The all‐6‐deoxy‐sugars containing tetrasaccharides were synthesized using an efficient convergent methodology employing a (2 + 2) glycosylation strategy. A key to this approach is utilizing a common disaccharide donor, which streamlines the assembly of both the tetrasaccharides by minimizing protecting group manipulations and enhancing overall efficiency. The disaccharide donor was synthesized through a highly chemoselective activation of a meticulously designed reactive thioglycoside donor, allowing for precise control over stereochemistry and regioselectivity during the glycosylation.