1-Benzoyl-3-[4-(3-benzoylthioureido)phenyl]thiourea

The molecule of the title compound, C22H18N4O2S2, lies across a crystallographic inversion centre. The molecule adopts a syn–anti configuration with respect to the positions of the carbonyl groups and terminal phenyl rings relative to the thione S atom across the C—N bond. There are two intramolecular N—H⋯O and C—H⋯S hydrogen bonds within each molecule, resulting in the formation of four six-membered S(6) rings. The central and terminal rings make a dihedral angle of 13.55 (15)°. In the crystal, molecules are linked by intermolecular C—H⋯S hydrogen bonds, forming R 2 2(14) rings and resulting in zigzag chains.

The molecule of the title compound, C 22 H 18 N 4 O 2 S 2 , lies across a crystallographic inversion centre. The molecule adopts a syn-anti configuration with respect to the positions of the carbonyl groups and terminal phenyl rings relative to the thione S atom across the C-N bond. There are two intramolecular N-HÁ Á ÁO and C-HÁ Á ÁS hydrogen bonds within each molecule, resulting in the formation of four sixmembered S(6) rings. The central and terminal rings make a dihedral angle of 13.55 (15) . In the crystal, molecules are linked by intermolecular C-HÁ Á ÁS hydrogen bonds, forming R 2 2 (14) rings and resulting in zigzag chains.

Comment
The title compound (Fig. 1) is a benzoyl thiourea derivatives and analogous to 1,2-bis(N'-benzoylthioureido)benzene, (Thiam et al., 2008), except that the other thiourea moiety is located in para position of the centre benzene ring. It is also an isomer of 1,1'-Diphenyl-3,3'-(p-phenylenedicarbonyl)dithiourea which was reported perviously (Hung et al., 2010). The bond lengths and angles are in normal ranges (Allen et al., 1987). The C=O bond length of 1.227 (3)Å is longer than the average C=O bond length (1.200 Å) and comparable to that observed in N-benzoyl-N'-phenylthiourea (Yamin et al., 2003). The C-N bond lengths are in the range of 1.330 (3) Å-1.415 (3)Å which are shorter than the normal single C-N bond length (1.469 Å) indicating double bond character (Arslan et al. 2004) owing to the resonance effect at the carbonyl-thiourea moiety. The thiourea fragment (S1/O1/N1/C6/C7/C8) is planar with a maximum deviation from its mean plane of 0.044 (3)Å for C8 atom. The central and terminal phenyl rings are essentially planar. The two rings make dihedral angles of 2.19 (13)° and 12.24 (15)°, respectively, with the thiourea fragment and the dihedral angle between those two rings is 13.55 (15)°.

Experimental
The title compound was synthesized according to previously reported method with some modification (Thiam et al. 2008).
Benzoyl chloride (10 mmol) was added to ammonium thiocyanate solution (10 mmol) and the mixture was left to react to completion. A yellowish product was filtered and added to a 1,4-diaminobenzene (5 mmol) in acetone and left at a refluxing temperature for 5 h. Yellowish precipitate was formed and a slow evaporation of the DMF solution of the product gave a crystal suitable for X-ray diffraction (Yield:75%).

Refinement
All H atoms attached to C and N were calculated and treated as riding on their parent atoms with C-H= 0.93Å and N-H= 0.86Å with U iso =1.2U eq (C, N).  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.