Z-Leu-Osu is widely used in peptide synthesis as a coupling reagent. It facilitates the formation of peptide bonds by activating carboxyl groups, making it essential in the production of custom peptides for research and pharmaceutical development. Its application is particularly valuable in solid-phase peptide synthesis (SPPS), where it ensures efficient and selective coupling of amino acids. Additionally, Z-Leu-Osu is employed in the synthesis of peptide-based drugs, protein studies, and biochemical research, where precise and high-yield peptide bond formation is critical. Its stability and reactivity make it a preferred choice in organic and medicinal chemistry laboratories.