3-Hydroxy-3-(2-oxo-2,3-dihydro-1H-indol-3-yl)-2,3-dihydro-1H-indol-2-one

The conformation of the title molecule, C16H12N2O3, is partly determined by an intramolecular C=O...π interaction between one carbonyl group and the five-membered ring of the other indolinone moiety. The crystal packing consists of layers parallel to (001) formed by a combination of N—H...O and O—H...O hydrogen bonds and π–π stacking interactions. Both the N—H...O and O—H...O hydrogen bonds generate inversion dimers