Used primarily as an intermediate in organic synthesis, especially in the preparation of indole-based pharmaceuticals and bioactive compounds. Its reactive acyl chloride group allows for easy attachment to amines or alcohols, enabling the formation of amides or esters. The presence of a nitro group enhances its utility in further functionalization reactions, such as reductions to amines, which can be used to build more complex molecular structures. Commonly employed in the development of medicinal agents where indole scaffolds are present, including anti-inflammatory, antiviral, and anticancer drugs. Also utilized in research settings for the synthesis of novel heterocyclic compounds with potential biological activity.