Z-Asp(OtBu)-OH is widely used in peptide synthesis as a protected form of aspartic acid. Its tert-butyl ester group provides stability during the coupling reactions, ensuring the aspartic acid residue remains intact while other amino acids are added to the peptide chain. This compound is particularly valuable in solid-phase peptide synthesis (SPPS), where selective deprotection is required to build complex peptides. It is also employed in the synthesis of peptide-based drugs, where precise control over the sequence and structure is critical. Additionally, Z-Asp(OtBu)-OH is utilized in research for developing bioactive peptides, enzyme inhibitors, and other therapeutic agents, owing to its ability to maintain the integrity of the aspartic acid side chain during chemical processes.