3-Pyrrolidinecarboxylic acid, 1-[3-(dimethylamino)propyl]-5-oxo-
1-[3-(Dimethylamino)propyl]-5-oxo-3-pyrrolidinecarboxylic acid
1-[3-(Dimethylamino)propyl]-2-oxo-4-pyrrolidinecarboxylic acid
1-[3-(Dimethylazaniumyl)propyl]-5-oxopyrrolidine-3-carboxylate