Benzo[b]thiophene-3-acetic acid is primarily used in the field of medicinal chemistry as a key intermediate in the synthesis of various pharmaceutical compounds. Its structure is particularly valuable in the development of nonsteroidal anti-inflammatory drugs (NSAIDs) and other therapeutic agents targeting inflammation and pain. Additionally, it serves as a building block in the creation of heterocyclic compounds, which are essential in drug discovery for their diverse biological activities. Its applications also extend to organic synthesis, where it is utilized to develop novel molecules with potential pharmacological properties.