Used in the synthesis of pharmaceutical intermediates, particularly in the development of β-lactam antibiotics. It serves as a chiral building block for penicillin and cephalosporin analogs due to its stereochemical purity and aryl-substituted amino acid structure. Its methoxyphenyl group enhances lipophilicity, which can improve cell membrane penetration in drug design. Also employed in asymmetric synthesis and catalysis where enantioselectivity is critical.