L-Fmoc-Aspartic acid α-tert-butyl ester is widely used in peptide synthesis, particularly in solid-phase peptide synthesis (SPPS). It serves as a protected form of aspartic acid, where the Fmoc group protects the amino group, and the tert-butyl ester protects the carboxylic acid group. This protection allows for selective deprotection during the synthesis process, enabling the controlled addition of amino acids to build peptides. It is especially valuable in synthesizing complex peptides and proteins, where precise control over the sequence and structure is critical. Additionally, it is utilized in the production of peptide-based drugs, biomaterials, and research tools for studying protein interactions and functions. Its stability and compatibility with SPPS make it a key reagent in both academic and industrial peptide chemistry.