Used primarily as a reference standard or impurity control in the pharmaceutical industry during the synthesis and quality testing of palbociclib, a CDK4/6 inhibitor used in cancer treatment. Helps ensure the purity, safety, and consistency of the final drug product by monitoring degradation products and process-related impurities. Also utilized in analytical studies such as HPLC and mass spectrometry for identification and quantification of related substances in active pharmaceutical ingredient batches.