Used primarily as a protected amino acid derivative (Boc-Asp-OMe) in peptide synthesis. The Boc (tert-butoxycarbonyl) group protects the alpha-amino functionality, enabling selective activation and coupling at the free alpha-carboxylic acid end. The side-chain carboxylic acid is protected as a methyl ester, which can be selectively hydrolyzed under basic conditions or retained for further reactions. Commonly employed in both solid-phase and solution-phase peptide synthesis to construct complex protein fragments. Its orthogonal protecting groups provide stability under diverse reaction conditions, making it essential for multi-step organic syntheses, especially in pharmaceutical development for precise amino acid sequence assembly. Also utilized in the synthesis of enzyme inhibitors and bioactive molecules.