In the title compound, C14H11NO4, the dihedral angle between the mean planes of the aromatic rings is 3.96 (12)° and an intra-molecular O-H⋯O hydrogen bond closes an S(6) ring. A short intra-molecular C-H⋯O contact is also seen. In the crystal, carb-oxy-lic acid inversion dimers linked by pairs of O-H⋯O hydrogen bonds generate R 2 (2)(8) loops. Conversely, the N-H group does not form a hydrogen bond. Aromatic π-π inter-actions exist at a centroid-centroid distance of 3.8423 (15) Å between the benzene rings. An extremely weak C-H⋯π inter-action also is present.
Keywords: crystal structure; hydrogen bonding; π–π interactions.