The title compound, C18H12N4O . H2O, adopts the keto tautomeric form and th
e azomethine C=N double bond is in the E configuration. The dihedral angle
between the planes of the diazafluorene moiety and the phenyl ring is 11.3
(1)degrees. In the solid state, the molecules form infinite chain-like stru
ctures via O-H ... N hydrogen bonds involving the water molecules and diaza
fluorene moieties.