This chemical is widely utilized in the field of bioconjugation and drug development due to its PEG (polyethylene glycol) spacer, which enhances solubility and stability of compounds. It serves as a key intermediate in the synthesis of antibody-drug conjugates (ADCs), enabling the attachment of therapeutic agents to antibodies for targeted cancer therapy. The t-butyl ester group provides protection during chemical reactions, ensuring selective modification of molecules. Additionally, it is employed in the development of peptide-based drugs, where the PEG linker improves pharmacokinetics and reduces immunogenicity. Its versatility also extends to the creation of functionalized polymers and biomaterials for controlled drug delivery systems.