O-Benzyl-L-Tyrosine Methyl Ester Hydrochloride is primarily used in peptide synthesis as a protected form of tyrosine. The benzyl group acts as a protective group for the hydroxyl side chain of tyrosine, preventing unwanted reactions during peptide bond formation. This compound is particularly valuable in solid-phase peptide synthesis (SPPS), where selective deprotection is required to build complex peptide sequences. It is also employed in the preparation of modified peptides and peptidomimetics for pharmaceutical research, enabling the study of structure-activity relationships in drug development. Additionally, it serves as an intermediate in the synthesis of bioactive compounds and enzyme inhibitors, contributing to advancements in medicinal chemistry.