Used as a substrate in enzymatic assays, particularly for detecting esterase and cholinesterase activity in biological samples. It is widely applied in histochemistry to localize enzyme activity in tissues through colorimetric detection, as enzyme hydrolysis releases 1-naphthol, which couples with diazonium salts to form visible dyes. Also employed in pesticide toxicity testing due to its sensitivity to inhibition by organophosphates and carbamates. Additionally, it serves as an intermediate in the synthesis of dyes, fragrances, and pharmaceuticals.