Isoquinoline-3-carboxylic acid finds applications primarily in the field of medicinal chemistry and drug development. It serves as a key intermediate in the synthesis of various biologically active compounds, including potential therapeutic agents. Its structure is often utilized in the design of molecules targeting enzymes or receptors involved in diseases such as cancer, inflammation, and neurological disorders. Additionally, it is employed in the development of fluorescent probes and imaging agents due to its unique chemical properties. Researchers also explore its role in creating novel materials with specific electronic or photophysical characteristics for use in organic electronics or sensors.