Telmisatran EP impurity C

Telmisatran EP Impurity C is a structurally related byproduct arising from the synthetic pathway of Telmisatran, characterized by a substituted tetrazole ring conjugated to a biphenyl moiety with a methoxy group at the para position. Its core scaffold retains the 2,4-dichlorobenzoyl functionality of the parent compound but features an additional ethyl ester linkage at the terminal carboxylic acid, distinguishing it as a partial hydrolysis intermediate. This impurity exhibits a planar conformation due to extended aromatic conjugation, enhancing its chromatographic retention profile. It serves as a critical HPLC reference standard for quantifying process-related impurities in Telmisatran drug substance analysis.