Used in bioconjugation and chemical biology, this compound serves as a linker for attaching functional groups or biomolecules. Its PEG (polyethylene glycol) spacer enhances solubility and reduces steric hindrance, making it ideal for creating stable conjugates in drug delivery systems. The tert-butyl ester group provides protection for the carboxylic acid, allowing selective deprotection in later stages of synthesis. It is commonly employed in the development of antibody-drug conjugates (ADCs) and targeted therapies, where precise molecular connections are crucial. Additionally, its structure is advantageous in peptide synthesis and the modification of proteins or small molecules for enhanced bioavailability and targeting efficiency.