Amlodipine imp G

Amlodipine imp G is a structurally related dihydropyridine derivative featuring a fully saturated 1,4-dihydropyridine core with a substituted phenyl ring and a methoxy group at the 4-position. It lacks the N-methyl substitution at the pyridine nitrogen present in the parent drug, resulting in a primary amine functionality. This impurity arises via demethylation during synthetic processes or thermal degradation pathways. It serves as a critical HPLC reference standard for quantifying N-demethylated byproducts in amlodipine formulations.