Isatin is widely used in the pharmaceutical industry as a key intermediate in the synthesis of various drugs, particularly those with antiviral, anticancer, and antimicrobial properties. Its derivatives are explored for their potential in treating diseases like HIV, tuberculosis, and certain types of cancer. In organic chemistry, it serves as a versatile building block for synthesizing heterocyclic compounds, which are crucial in developing dyes, pigments, and agrochemicals. Additionally, isatin-based compounds are studied for their role in neuroscience, particularly in inhibiting enzymes like monoamine oxidase, which is relevant in treating neurological disorders. Its applications also extend to material science, where it is used in the development of organic electronic materials and sensors.