This chemical is primarily used in bioconjugation and biochemical research, particularly in the modification of biomolecules. Its PEG4 spacer enhances solubility and reduces steric hindrance, making it suitable for attaching to proteins, peptides, or other biological targets. The t-butyl ester groups provide protection for carboxylic acids, which can be deprotected under specific conditions to enable further functionalization. It is often employed in the development of desthiobiotin-based probes or affinity tags for applications such as pull-down assays, protein labeling, and drug delivery systems. Its structure allows for controlled release or activation of functional groups, making it valuable in designing targeted therapeutic agents or diagnostic tools.