N-Me-Ser-OH.HCl is the hydrochloride salt of N-methylserine, a modified derivative of the amino acid serine used in peptide synthesis. It enables selective incorporation of N-methylserine into peptide chains, which can enhance stability, alter biological activity, or facilitate specific interactions during the formation of peptide bonds. It is particularly valuable in solid-phase peptide synthesis (SPPS) for constructing complex peptides and proteins. The hydrochloride salt form improves stability and solubility, making it easier to handle in various organic solvents. It is also employed in pharmaceutical development, especially for peptide-based drugs, where precise control over amino acid incorporation is essential. Additionally, it serves as a building block in biochemical research for studying protein structure and function.