Used primarily in hair dye formulations, this compound acts as a precursor in the development of long-lasting, oxidative color. It reacts with other dye components, such as couplers, inside the hair shaft to form larger, colored molecules that are resistant to washing out. Its high reactivity and ability to produce intense, uniform shades—especially dark browns and blacks—make it valuable in permanent hair color products. Also found in some textile dyes where strong, stable coloration is required. Due to its sensitivity, formulations typically control pH and include antioxidants to maintain stability before use. Additionally, it serves as a key intermediate in the synthesis of specialty chemicals, pharmaceuticals, and biomolecules, leveraging its aminopyrimidine core and reactivity with carbonyl compounds to build complex cyclic structures.