Widely used in solid-phase peptide synthesis, this compound serves as a protected amino acid derivative for incorporating phosphotyrosine mimics into peptides. Its main application lies in the preparation of biologically active peptides that require phosphorylated tyrosine residues for function, such as substrates or inhibitors of protein tyrosine kinases and phosphatases. The phospho group is protected with a benzyloxy group, allowing for selective deprotection under mild conditions, while the Fmoc group enables orthogonal protection strategies in stepwise peptide assembly. It is especially valuable in research related to signal transduction pathways, drug discovery, and the study of post-translational modifications in proteins.