Used in bioconjugation applications, particularly in click chemistry due to the DBCO group, which reacts with azides without the need for a catalyst. The PEG4 spacer enhances solubility and reduces aggregation, making it ideal for labeling biomolecules in aqueous environments. The tripeptide Gly-Gly-Gly serves as a flexible linker, often used to mimic natural peptide sequences or to provide spacing in probe design. Commonly applied in the development of fluorescent probes, drug delivery systems, and protein modifications where controlled, site-specific reactions are required.