The present invention relates to highly-pure pyrroloquinolinyl-pyrrole-2,5-dione and pyrroloquinolinyl-pyrrolidine-2,5-dione, for example, 3-(5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinolin-1-yl)-4-(1H-indol-3-yl)-1H-pyrrole-2,5-dione, 3-(5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinolin-1-yl)-4-(1H-indol-3-yl)pyrrolidine-2,5-dione, and pharmaceutically acceptable salts, solvates, and diastereomers thereof. The present invention also relates to methods for preparing highly-pure pyrroloquinolinyl-pyrrole-2,5-dione and pyrroloquinolinyl-pyrrolidine-2,5-dione, for example, 3-(5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinolin-1-yl)-4-(1H-indol-3-yl)-1H-pyrrole-2,5-dione, 3-(5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinolin-1-yl)-4-(1H-indol-3-yl)pyrrolidine-2,5-dione, and pharmaceutically acceptable salts, solvates, and diastereomers thereof.
