L-Tyrosine tert-butyl ester is widely used in peptide synthesis as a protecting group for the carboxylic acid functionality of tyrosine. This compound helps prevent unwanted side reactions during the formation of peptide bonds, ensuring the integrity and specificity of the peptide chain. It is particularly valuable in solid-phase peptide synthesis (SPPS), where selective deprotection and coupling steps are critical. Additionally, it finds application in the development of pharmaceuticals and bioactive peptides, where tyrosine residues play a key role in biological activity. Its tert-butyl ester group is stable under acidic conditions but can be easily removed under mild acidic conditions, making it a versatile tool in organic and medicinal chemistry.