Used as a key intermediate in the synthesis of organic pigments and dyes, particularly in the production of azo pigments which are valued for their color stability and intensity. Commonly employed in the colorant industry for inks, coatings, and plastics. Also utilized in analytical chemistry as a chromogenic reagent for the detection of oxidizing agents and certain enzymes like peroxidase, where it produces a visible color change upon reaction. Requires careful handling due to potential health and environmental hazards.