EPY0000591
Vinpocetine impurity B - (13aS,13bS)-13a-ethyl-2,3,5,6,13a,13b-hexahydro-1H-indolo[3,2,1-de]pyrido[3,2,1-ij][1,5]naphthyridine-12-carboxylate (apovincamine)
EPY0000590
Vinpocetine impurity A - (12RS,13aSR,13bSR)-13a-ethyl-12-hydroxy-2,3,5,6,12,13,13a,13b-octahydro-1H-indolo[3,2,1-de]pyrido[3,2,1-ij][1,5]naphthyridine-12-carboxylate (ethyl vincaminate)