Used in pharmaceutical and biochemical research as an intermediate for synthesizing bioactive compounds, peptides, and other organic molecules. As a protected derivative of DL-tyrosine, with the carboxylic acid group esterified as ethyl ester and the amino group as hydrochloride salt, it improves solubility in organic solvents and enables selective reactions in peptide synthesis. Commonly applied in the development of enzyme substrates, receptor ligands, and studies of amino acid metabolism and transport. Suitable for laboratory research applications.