Widely used in peptide synthesis, this compound serves as a protected amino acid building block, enabling selective formation of peptide bonds without unwanted side reactions at the cysteine thiol group. The Boc (tert-butyloxycarbonyl) group protects the alpha-amino function, while the tert-butyl group shields the thiol side chain, ensuring stability under various reaction conditions. The dicyclohexylammonium salt form improves crystallinity and solubility in organic solvents, facilitating purification and handling during solid-phase or solution-phase peptide assembly. It is particularly valuable in the synthesis of complex peptides and proteins where cysteine residues must remain protected until final deprotection steps.