Used primarily as a reference standard in pharmaceutical quality control and analytical testing. It serves as a key metabolite marker in pharmacokinetic studies of nifedipine, helping researchers assess drug metabolism and bioavailability. Commonly employed in HPLC and LC-MS methods to validate assay accuracy and monitor degradation products in nifedipine formulations. Also utilized in research settings to study oxidative metabolism pathways mediated by cytochrome P450 enzymes, particularly CYP3A4.