The asymmetric unit of the title compound, C15H16N2O3, contains two independent mol-ecules, which present a different conformation of the carb-oxy-lic acid side chain [C-C-C-OH torsion angles = 65.3 (7) and -170.1 (5)°]. In both mol-ecules, the di-hydro-pyridazinone ring adopts a geometry inter-mediate between a twisted-boat and a half-chair conformation, while the central six-membered ring is almost in a half-boat conformation. In the crystal, mol-ecules are linked by O-H⋯Ok (k = ketone) hydrogen bonds, generating [01-1] chains. Aromatic π-π stacking contacts between the benzene and the di-hydro-pyridazinone rings [centroid-centroid distance [3.879 (9) Å] are also observed.
Keywords: crystal structure; pyridazinone moiety; stat3 inhibitor.