This compound is widely used in bioconjugation and chemical biology due to its unique properties. It serves as a linker molecule, enabling the attachment of various functional groups or biomolecules to proteins, peptides, or other substrates. The Boc (tert-butoxycarbonyl) group provides protection for the aminoxy functionality during synthetic processes, which can be selectively removed when needed. The PEG4 (polyethylene glycol) spacer enhances solubility and reduces steric hindrance, making it ideal for applications in drug delivery systems, where it helps improve the pharmacokinetics and bioavailability of therapeutic agents. Additionally, it is employed in the development of antibody-drug conjugates (ADCs) and other targeted therapies, where precise and stable conjugation is critical. Its acid group allows for further functionalization or coupling with amines or other reactive groups, making it a versatile tool in organic synthesis and bioconjugation strategies.