The title compound, C14H12N2O4, is a Schiff base that exists in the keto-enamine tautomeric form and adopts a Z configuration. The mol-ecule is almost planar, the rings making a dihedral angle of 4.99 (7)°. The mol-ecular structure is stabilized by an intra-molecular N-H⋯O hydrogen bond forming an S(6) ring motif. In the crystal, inversion-related mol-ecules are linked by pairs of O-H⋯O hydrogen bonds, forming dimers with an R 2 2(18) ring motif. The dimers are linked by pairs of C-H⋯O contacts with an R 2 2(10) ring motif, forming ribbons extended along the [20] direction. Hirshfeld surface analysis, two-dimensional fingerprint plots and the mol-ecular electrostatic potential surfaces were used to analyse the inter-molecular inter-actions present in the crystal, indicating that the most important contributions for the crystal packing are from H⋯H (33.9%), O⋯H/H⋯O (29.8%) and C⋯H/H⋯C (17.3%) inter-actions.
Keywords: Hirshfeld surface analysis; Schiff base; crystal structure; hydrogen bonding.