Used in organic synthesis, particularly in the preparation of heterocyclic compounds and dyes, including azo and indigo dyes for applications in textiles, leather, printing inks, and photographic developers due to its redox properties. It serves as a building block in pharmaceuticals for the development of drugs targeting central nervous system disorders, anti-inflammatory agents, and CNS stimulants. Its amino and hydroxyl functional groups allow for use in coupling reactions and the formation of stable azo dyes. Additionally, it finds application in research settings for the study of aromatic amine reactivity, as a derivatizing agent in analytical chemistry, and in biochemical research to investigate oxidation reactions of proteins and amino acids, especially in biological systems related to pigment formation. It is also employed with catalysts in organic synthesis requiring specific functionalized benzene structures to control reaction positions and yield desired products.