Used in pharmaceutical and polymer research to introduce a short polyethylene glycol (PEG) spacer between molecules. The Boc-protected terminal groups allow for controlled deprotection and further coupling reactions, making it ideal for building complex molecules in peptide synthesis, drug delivery systems, and bioconjugation. Its hydrophilic nature improves solubility and stability of conjugated compounds. Commonly used in the development of PEGylated therapeutics and functionalized biomaterials.