Crystal structure of N-(2-amino-5-cyano-4-methylsulfanyl-6-oxo-1,6-dihydropyrimidin-1-yl)-4-bromobenzenesulfonamide dimethylformamide monosolvate

In the title compound compound, the phenyl and pyrimidine rings are inclined to one another at 31.72 (6)°. The residues are associated into ribbons parallel to [110] by three classical hydrogen bonds. Adjacent ribbons are connected by translation parallel to the c axis by a ‘weak’ hydrogen bond to form a layer structure parallel to (1-10), while a further contact connects the residues in the third dimension.

The title compound, C 12 H 10 BrN 5 O 3 S 2 ÁC 3 H 7 NO, displays an almost planar amine group. The interplanar angle between the rings is 31.72 (6) . The residues are associated into ribbons parallel to [110] by three classical hydrogen bonds; one from each amine H amine to O DMF and one from NH amide to O oxo . Adjacent ribbons are connected by translation parallel to the c axis by a 'weak' hydrogen bond H methyl Á Á ÁO sulfonyl to form a layer structure parallel to (110), while a further contact H bromophenyl Á Á ÁO sulfonyl connects the residues in the third dimension.

Chemical context
We are conducting studies directed towards exploring the synthetic potential of dimethyl N-cyanoimido-S,S-dimethyldithiocarbonate and other ketene dithioacetals for synthesizing new classes of antimetabolites (Elgemeie & Mohamed, 2014;Elgemeie et al., 2007Elgemeie et al., , 2009. We have recently reported various successful approaches to the synthesis of mercaptopyrimidines by the reaction of this compound with active methylene functions (Elgemeie & Sood, 2001;Elgemeie et al., 2003). In an extension of this work, we describe a one-pot synthesis of N-(2-amino-5-cyano-4-(methylthio)-6-oxopyrimidin-1(6H)-yl)-4-bromobenzenesulfonamide (I) by the reaction of dimethyl N-cyanodithioiminocarbonate with N 0 -(4bromophenyl)sulfonyl-2-cyanoethanehydrazide. The chemical nature was proposed on the basis of elemental analysis and spectroscopic data and its X-ray structure determination was undertaken to confirm the nature of the product. We have recently presented the structure of a related pyrimidine (Elgemeie et al., 2015). ISSN 2056-9890

Structural commentary
The structure of the title compound, which proved to be the dimethylformamide solvate (I)ÁDMF, is shown in Fig. 1. The ring systems are as expected almost planar, with r.m.s. deviations of 0.002 Å for the phenyl and 0.04 Å for the pyrimidine ring. The substituent atoms N4 and S1 deviate significantly from the pyrimidine plane [by 0.199 (2) and 0.257 (2) Å respectively, to opposite sides of the plane]. The interplanar angle is 31.72 (6) , and is also associated with the torsion angles C12-C11-S2-N2 88.10 (12), C11-S2-N2-N1 78.98 (11) and S2-N2-N1-C2 100.31 (12) . The amino group at N4 is almost planar, with the nitrogen atom lying just 0.035 (11) Å out of the plane of its substituents.

Supramolecular features
The components are associated into ribbons parallel to [110] (Fig. 2) by three classical hydrogen bonds ( Table 1). Two of these, H02Á Á ÁO4(1 À x, Ày, 1 À z) and H03Á Á ÁO4, involve the dimethylformamide oxygen atom and lead to the formation of inversion-symmetric rings of graph set R 2 4 (8). The third hydrogen bond, H01Á Á ÁO1(2 À x, 1 À y, 1 À z), also forms inversion-symmetric rings, but of graph set R 2 2 (10). There are two short and acceptably linear C-HÁ Á ÁO contacts that may be assumed to represent 'weak' hydrogen bonds; H7BÁ Á ÁO3 connects neighbouring ribbons by translation parallel to the c axis, thus completing a layer structure parallel to (110), while H12Á Á ÁO2 connects the residues in the third dimension via the inversion operator (1 À x, 1 À y, 1 À z).
The bromine atom is involved in two secondary contacts: a halogen bond of 3.4582 (10) Å with O1(2 À x, 2 À y,1 À z) and a weak hydrogen bond of 3.05 Å from H17(x, 1 + y, z), with an angle of 124 at hydrogen. These interactions also connect the residues in the third dimension.

Synthesis and crystallization
Dimethyl N-cyanoimido-S,S-dimethyl-dithiocarbonate (0.01 mol) was added to a stirred solution of N 0 -(4-bromo- The formula unit of compound (I)ÁDMF in the crystal. Displacement ellipsoids correspond to 50% probability levels. The hydrogen bond H03Á Á ÁO4 is drawn as a thin dashed line. Table 1 Hydrogen-bond geometry (Å , ).

Refinement
Crystal data, data collection and structure refinement details are summarized in Table 2. The NH hydrogens were refined freely. The methyl groups were refined as idealized rigid groups allowed to rotate but not tip.    (Agilent, 2013); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Special details
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. Non-bonded contact: 3.4582 (0.0010) Br1 -O1_$6 Operator for generating equivalent atoms: $6 -x + 2, -y + 2, -z + 1 ============================================================================ Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane) 8.0547 ( Rms deviation of fitted atoms = 0.0022 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 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.