Used as an active ester coupling agent in peptide synthesis, facilitating efficient amide bond formation under mild conditions. Commonly employed in bioconjugation processes to link biomolecules such as proteins or antibodies with labels, drugs, or polymers. Its hydroxyl group allows further functionalization or attachment to surfaces in diagnostic or sensor applications. Stable in aqueous solutions at physiological pH, making it suitable for use in biological labeling and crosslinking reactions. Also utilized in the preparation of pharmaceutical intermediates where selective acylation is required.