Used primarily as an intermediate in organic synthesis, especially in the production of dyes and pigments. It plays a key role in the manufacture of leuco dyes for thermal paper, commonly found in receipts and labels. Also utilized in the development of functional materials such as photochromic and electrochromic compounds due to its electron-donating properties. Its derivatives are explored in pharmaceutical research for potential bioactive molecules, particularly in central nervous system agents. Additionally, it serves as a building block in the synthesis of indigo-based colorants and specialty heterocyclic compounds.