Used in bioorthogonal labeling and detection applications, particularly in fluorescence imaging. Enables selective tagging of biomolecules in live cells through click chemistry, allowing high-resolution visualization of cellular structures and dynamic processes. Its alkyne group reacts efficiently with azide-labeled compounds via copper-catalyzed azide-alkyne cycloaddition (CuAAC), making it valuable for protein, nucleic acid, and glycan labeling. Also applied in multiplexed imaging due to its bright red fluorescence and photostability, suitable for advanced microscopy techniques.