Used as an intermediate in the synthesis of sulfa drugs, particularly in the production of antimicrobial agents. It serves as a key building block in the preparation of sulfonamide-based pharmaceuticals, which are known for their ability to inhibit bacterial growth by interfering with folic acid synthesis. Also employed in the development of dyes and indicators due to its aromatic amine structure, which can undergo diazotization and coupling reactions. Its derivatives are found in some analytical reagents for detecting metal ions and in the formulation of certain photochromic materials.