4-[(5R*,10bR*)-2-Methyl-1,10b-dihydro-pyrazolo[1,5-c][1,3]benzoxazin-5-yl]benzoic acid.

In the title compound, C(18)H(16)N(2)O(3), a potential inhibitor of the cyclo-oxygenase-2 isoenzyme, the pyrazoline ring exists in a flattened envelope conformation with one C atom deviating by 0.463 Å from the mean plane of the remaining four atoms. The puckering of the central oxazine ring is more severe, with one N atom and one C atom displaced by 0.235 (6) and 0.370 (2) Å, respectively, on opposite sides of the mean plane defined by the other four atoms; the conformation is that of a half-chair. As a result, the mol-ecule as a whole is not planar. The carboxyl group is involved in an inter-molecular O-H⋯N hydrogen bond, which links the mol-ecules into centrosymmetric dimers.