(E)-4-Amino-N′-(2-hydroxy-5-methoxybenzylidene)benzohydrazide monohydrate

In the title compound, C15H15N3O3·H2O, the hydazide Schiff base molecule shows an E conformation around the C=N bond. An intramolecular O—H⋯N hydrogen bond makes an S(6) ring motif. The dihedral angle between the substituted phenyl rings is 23.40 (11)°. The water molecule mediates linking of neighbouring molecules through O—H⋯(O,O) hydrogen bonds into infinite chains along the a axis, which are further connected together through N—H⋯O hydrogen bonds, forming a two-dimensional network parallel to (001). C—H⋯O interactions aso occur.

In the title compound, C 15 H 15 N 3 O 3 ÁH 2 O, the hydazide Schiff base molecule shows an E conformation around the C N bond. An intramolecular O-HÁ Á ÁN hydrogen bond makes an S(6) ring motif. The dihedral angle between the substituted phenyl rings is 23.40 (11) . The water molecule mediates linking of neighbouring molecules through O-HÁ Á Á(O,O) hydrogen bonds into infinite chains along the a axis, which are further connected together through N-HÁ Á ÁO hydrogen bonds, forming a two-dimensional network parallel to (001). C-HÁ Á ÁO interactions aso occur.
The asymmetric unit of the title compound, Fig. 1, comprises a molecule of the title hydazide Schiff base and a water molecule of crystallization. It shows E conformation around C═N bond. The bond lengths (Allen et al., 1987) and angles are within normal ranges and are comparable to the related structures (Kargar et al., 2012a,b;Xu, 2012;Shi & Li, 2012;Bakir & Green, 2002). Intramolecular O-H···N hydrogen bond makes S(6) ring motif (Bernstein et al., 1995). The dihedral angle between the substituted phenyl rings is 23.40 (11)

Experimental
The title compound was synthesized by adding 1 mmol of methyl 4-aminobenzoate to a solution of 5-methoxysalicylaldehyde (1 mmol) in methanol (30 ml). The mixture was refluxed with stirring for 50 min and after cooling to room temperature a light-yellow precipitate was filtered and washed with diethylether and dried in air. white prismatic crystals of the title compound, suitable for X-ray structure analysis, were recrystallized from ethanol by slow evaporation of the solvents at room temperature over several days.

Refinement
The N-and O-bound H-atoms were located in a difference Fourier map and constrained to refine to the parent atoms with U iso (H) = 1.2 or 1.5 U eq (N, O), respectively, see Table 1. The rest of the H atoms were positioned by riding model approximation with C-H = 0.93 and U iso (H) = k × U eq (C) with k = 1.2 for CH and 1.5 for CH 3 . In the absence of sufficient anomalous scattering 1437 Friedel pairs were merged.

Computing details
Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008)′; software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).   where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.14 e Å −3 Δρ min = −0.13 e Å −3 Special details Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > 2sigma(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.