Used in peptide synthesis as a protected lysine derivative, enabling selective amino group protection during solid-phase or solution-phase peptide coupling. The Boc group shields the alpha-amino functionality, while the methyl ester protects the carboxylic acid end, allowing stepwise assembly of complex peptides without unwanted side reactions. Commonly employed in the preparation of biologically active peptides, pharmaceutical intermediates, and research compounds where controlled deprotection and coupling are required. Its solubility in organic solvents makes it suitable for use in automated synthesizers and multi-step synthetic routes.