Indole-6-carboxylic acid is primarily used in the synthesis of various pharmaceutical compounds. It serves as a key intermediate in the production of drugs targeting neurological and psychiatric disorders, such as serotonin receptor modulators. Additionally, it is utilized in the development of anti-inflammatory and anticancer agents due to its ability to interact with specific biological pathways. In research, it is employed to study indole derivatives and their potential therapeutic effects. Its role in organic synthesis also extends to the creation of agrochemicals and dyes, where its structural properties contribute to the development of novel compounds with specific functionalities.