N-Desmethyl enzalutamide

N-Desmethyl enzalutamide is a structurally related impurity derived from enzalutamide via N-demethylation of the sulfonamide moiety. It retains the core naphthalene-triazole scaffold and fluorinated phenyl substituent but features an unsubstituted sulfonamide nitrogen. This compound exhibits altered lipophilicity compared to the parent drug due to the absence of the methyl group, impacting its chromatographic behavior. It arises during synthetic pathways or degradation processes involving enzalutamide. This impurity serves as a critical HPLC reference standard for quantitative impurity profiling in API batches.