4-(3-Nitrophenyl)-1-(2-oxoindolin-3-ylidene)thiosemicarbazide

In the title compound, C15H11N5O3S, intramolecular N—H⋯N hydrogen bonding forms an S(5) ring motif, whereas N—H⋯O and C—H⋯S interactions type complete S(6) ring motifs. The 2-oxoindoline and 3-methoxyphenyl rings are almost planar, with r.m.s. deviations of 0.0178 and 0.0149 Å, respectively, and form a dihedral angle of 33.59 (3)°. In the crystal, molecules are interlinked through the nitro groups in an end-to-end fashion via N—H⋯O and C—H⋯O interactions.

In the title compound, C 15 H 11 N 5 O 3 S, intramolecular N-HÁ Á ÁN hydrogen bonding forms an S(5) ring motif, whereas N-HÁ Á ÁO and C-HÁ Á ÁS interactions type complete S(6) ring motifs. The 2-oxoindoline and 3-methoxyphenyl rings are almost planar, with r.m.s. deviations of 0.0178 and 0.0149 Å , respectively, and form a dihedral angle of 33.59 (3) . In the crystal, molecules are interlinked through the nitro groups in an end-to-end fashion via N-HÁ Á ÁO and C-HÁ Á ÁO interactions.
The molecules are interlinked through nitro groups ( Fig. 2) in end to end fashion due to N-H···O and C-H···O interactions completing R 2 2 (8) ring motifs. The N=O···π and C=S···π interaction play role in stabilizing the molecules.

Experimental
To a hot solution of isatin (0.74 g, 5.0 mmol) in ethanol (10 ml) containing a few drops of glacial acetic acid was added 4-(3-nitrophenyl)thiosemicarbazide (1.06 g, 5.0 mmol) dissolved in ethanol (10 ml) under stirring. The reaction mixture was then heated under reflux for 2 h. The orange crystalline solid formed during heating was collected by suction filtration.
Thorough washing with hot ethanol followed by ether provided the desired compound (I) in pure form (1.08 g, 63%), m.p. 539 K. The single crystals of (I) were grown in ethyl acetate by slow evaporation at room temperature.

Refinement
The H-atoms were positioned geometrically (N-H = 0.86 Å, C-H = 0.93 Å) and refined as riding with U iso (H) = xU eq (C, N), where x = 1.2 for all H-atoms.

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 > σ(F 2 ) is used only for calculating Rfactors(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.