Used primarily as a reference standard or impurity marker in pharmaceutical analysis, this compound plays a critical role in quality control during the synthesis and purification of nintedanib, a tyrosine kinase inhibitor used in the treatment of idiopathic pulmonary fibrosis and certain cancers. It helps in validating analytical methods such as HPLC and LC-MS by providing a known impurity profile, ensuring drug purity, stability, and regulatory compliance. Its presence is monitored to assess the efficiency of manufacturing processes and to support the development of safe and effective formulations.