Indolin-6-ol is primarily used as an intermediate in the synthesis of pharmaceuticals and biologically active compounds. Its structure supports the development of kinase inhibitors and neuroprotective agents, making it valuable in medicinal chemistry research. It is also employed in the creation of dyes and fluorescent probes due to its aromatic and electron-donating properties, which enhance optical characteristics. Additionally, derivatives of indolin-6-ol appear in the development of antioxidants and anti-inflammatory agents, where the hydroxyl group contributes to radical scavenging activity. Its versatility in ring functionalization allows for tailored modifications in drug design and materials science.