In the title compound, C 18 H 20 N 2 O 7 , the dihedral angle between the aromatic rings is 7.28 (7)° and the almost planar conformation of the molecule is supported by an intramolecular O—H...O hydrogen bond, which closes an S (6) ring. In the crystal, weak C—H...O hydrogen bonds and aromatic π–π stacking link the molecules into a three-dimensional network. A Hirshfeld surface analysis showed that the major contribution to the intermolecular interactions are van der Waals interactions (H...H contacts), accounting for 48.4% of the surface.