Nadolol EP impurity F

Nadolol EP impurity F is a structurally related degradation byproduct arising from oxidative deamination of the parent beta-blocker, featuring a substituted benzene ring with a methoxy group at the 4-position and a phenoxypropanolamine side chain lacking the chloro substituent. The compound retains the core aromatic ether and secondary amine moieties but exhibits a truncated aliphatic chain due to cleavage at the amide linkage. This impurity serves as a critical HPLC reference standard for quantifying process-related degradation in Nadolol active pharmaceutical ingredient manufacturing.