Used primarily as a metabolite reference standard in pharmaceutical research and development, particularly in pharmacokinetic and metabolic studies of sunitinib, a tyrosine kinase inhibitor used in cancer treatment. It helps in understanding the metabolic pathways and drug interactions of sunitinib in biological systems. Commonly employed in bioanalytical assays such as LC-MS/MS for quantification in plasma, serum, or other biological matrices during clinical trials and therapeutic drug monitoring. Also utilized in toxicity studies to assess the contribution of metabolites to overall drug safety and efficacy.