Used in solid-phase peptide synthesis to introduce a lysine residue with orthogonal protection. The Fmoc group allows for temporary α-amino protection that can be removed under mild basic conditions, while the Boc group protects the side-chain amine and remains stable during Fmoc deprotection. The methyl group on the side chain (Me) acts as a permanent protecting group in some synthetic strategies, enabling selective modification later. This makes the compound valuable for synthesizing complex peptides and proteins, especially those requiring post-translational modifications or labeled derivatives. Commonly applied in research settings for drug discovery, epitope synthesis, and development of bioactive peptides.