Abstract
In the title compound, C21H17N3O4 center dot H2O, the coumarin ring system is almost planar (r.m.s. deviation = 0.002 angstrom) and makes dihedral angles of 1.50 (7) and 57.75 (7)degrees with the pyrazole and phenyl rings, respectively. The dihedral angle between the pyrazole and phenyl rings is 56.60 (9)degrees. The pyrazole ring adopts a twisted comformation. The molecular conformation is stabilized by intramolecular N-H center dot center dot center dot O and C-H center dot center dot center dot O hydrogen bonds, both of which form S(6) ring motifs. In the crystal, each water molecule is linked to its adjacent organic molecule via pairs of O-H center dot center dot center dot O hydrogen bonds. The packing is further consolidated by pairs of intermolecular C-H center dot center dot center dot O hydrogen bonds, which link the molecules into dimers; the dimers are stacked along the b axis.