Used as a key intermediate in the synthesis of photoremovable protecting groups for amino acids and peptides. Enables light-controlled release of bioactive molecules in research settings, particularly in neuroscience and cell biology for precise spatiotemporal activation. Commonly applied in studies involving caged glutamate, allowing targeted stimulation of neurons with high temporal and spatial resolution. Its nitroindoline-based structure provides good photochemical stability and efficient uncaging upon exposure to near-UV light.