3-Ethyl 5-methyl (S)-2-((2-(1,3-dioxoisoindolin-2-yl)ethoxy)methyl)-6-methyl-4-phenyl-1,4-dihydropyridine-3,5-dicarboxylate

3-Ethyl 5-methyl (S)-2-((2-(1,3-dioxoisoindolin-2-yl)ethoxy)methyl)-6-methyl-4-phenyl-1,4-dihydropyridine-3,5-dicarboxylate is an impurity of amlodipine.