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Acta Crystallogr Sect E Struct Rep Online. 2009 January 1; 65(Pt 1): o98–o99.
Published online 2008 December 13. doi:  10.1107/S1600536808041214
PMCID: PMC2968005

4-[(5-Bromo-2-hydroxy­benzyl­idene)amino]-N-(4,6-dimethyl­pyrimidin-2-yl)benzene­sulfonamide–4-bromo-2-[(E)-({4-[(4,6-dimethyl­pyrimidin-2-yl)sulfamo­yl]phen­yl}iminio)meth­yl]phenolate [0.61 (7)/0.39 (7)]

Abstract

The title compound, 0.61C19H17BrN4O3S·0.39C19H17BrN4O3S, is a Schiff base derived from 5-bromo­salicylaldehyde and 4-amino-N-(4,6-dimethyl-2-pyrimidin­yl)benzene­sulfonamide(sulfamethazine) and is isostructural with its chloro analogue. The geometry of the title mol­ecule points to the enol (OH—C=C—C=N) form as the major tautomer, however two electron-density maxima corresponding to the H atoms of the OH and NH groups, found in the region of a strong intra­molecular N(...)H(...)O hydrogen bond, do not allow the elimination of the presence of the zwitterionic (O—C=C—C=NH+) form in the crystal. Refinement of the occupancies of these H atoms gave a 0.61 (7):0.39 (7) ratio of the enolic and zwitterionic forms. The two benzene rings within the mol­ecule are nearly coplanar and the central benzene ring forms a dihedral angle of 84.1 (1)° with the pyrimidine fragment. An inter­molecular N—H(...)O hydrogen bond links mol­ecules into chains extended along the a axis and a C—H(...)O link is also present. The H atoms of one of the methyl groups are disordered over two sites with an occupancy ratio of 0.72 (7):0.28 (7).

Related literature

For the crystal structures of similar sulphonamides, see: Chohan et al. (2008a [triangle],b [triangle]); Shad et al. (2008 [triangle]); Tahir et al. (2008 [triangle]).

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Object name is e-65-00o98-scheme1.jpg

Experimental

Crystal data

  • 0.61C19H17BrN4O3S·0.39C19H17BrN4O3S
  • M r = 461.34
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-65-00o98-efi1.jpg
  • a = 11.7919 (9) Å
  • b = 13.9965 (8) Å
  • c = 23.5117 (17) Å
  • V = 3880.5 (5) Å3
  • Z = 8
  • Mo Kα radiation
  • μ = 2.26 mm−1
  • T = 296 (2) K
  • 0.20 × 0.16 × 0.14 mm

Data collection

  • Bruker KAPPA APEXII CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2005 [triangle]) T min = 0.650, T max = 0.725
  • 19597 measured reflections
  • 3428 independent reflections
  • 1961 reflections with I > 2σ(I)
  • R int = 0.081

Refinement

  • R[F 2 > 2σ(F 2)] = 0.048
  • wR(F 2) = 0.131
  • S = 1.00
  • 3428 reflections
  • 257 parameters
  • H-atom parameters constrained
  • Δρmax = 0.35 e Å−3
  • Δρmin = −0.65 e Å−3

Data collection: APEX2 (Bruker, 2007 [triangle]); cell refinement: SAINT (Bruker, 2007 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]) and PLATON (Spek, 2003 [triangle]); software used to prepare material for publication: WinGX publication routines (Farrugia, 1999 [triangle]) and PLATON.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808041214/gk2160sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808041214/gk2160Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors acknowledge the Higher Education Commission, Islamabad, Pakistan, for funding the purchase of the diffractometer at GCU, Lahore.

supplementary crystallographic information

Comment

As a result of vital pharmacological effects of sulfonamide and their derivatives, there is a rising attention in synthesizing and biotesting of these derivatives. In the vision of the versatile biological chemistry of sulfonamides, we have synthesized and recently published the crystal structures of several compounds from this group (Chohan et al., 2008a, 2008b; Shad et al., 2008; Tahir et al., 2008). In the same continuation, we herein report the structure of the title compound.

The title compound (I) (Fig. 1) was prepared from sulfamethazine and 5-bromosalicylaldehyde. The crystal of the title compound is isostructural with 4-(5-chloro-2-hydroxybenzylideneamino)-N-(4,6-dimethylpyrimidin-2-yl)benzenesulfonamide (II) (Chohan et al., 2008b). In the crystal two tautomers, enolic and zwitterionic, with an approximate ratio of 3:2 coexists, as shown by the refinement of H atom occupancies from the N-H and O-H groups.

We shall restrict discussion to comparison of the bond geometry between (I) and (II). The longest bond in the molecule is C3—Br1, having bond distance 1.890 (5) Å. The bond distances in (I), S1—N2 [1.629 (4) Å] and S1—C11 [1.753 (4) Å] remain equal within experimental errors with those observed in (II). The range of S—O [1.416 (3)–1.431 (3) Å] bond lengths is increased compared to 1.422 (2)–1.4282 (19) Å in (II). The bond angles around the S1-atom are slightly changed. The geometry of intramolecular as well as intermolecular H-bonding is given in Table 1 and shown in Fig 2.

Experimental

Sulfamethazine (0.5566 g, 2 mmol) in ethanol (15 ml) was reacted with ethanolic (10 ml) solution of 5-bromosalicylaldehyde (0.4020 g, 2 mmol). The mixture was refluxed for 3 h. The colour of the solution gradually changed from colourless to orange-red. The solution was then cooled to room temperature, filtered and volume reduced to about one-third on rotary evaporator. After 12 days crystals of the title compound were obtained.

Refinement

The positions of H-atoms attached to O1 and N1 were determined from the difference Fourier synthesis and in the refinement these atoms were constrained to ride on their parent atoms. Their occupancy factors were allowed to refine with the the sum of the occupancy factors constrained to 1.00. Remaining H-atoms were positioned geometrically, with C—H = 0.93-0.96 Å. The Uiso(H) = xUeq(C, N, O), where x = 1.5 for methyl H, H1N, H1O and x = 1.2 for all other H atoms. The H-atoms of one of the methyl groups are disordered over two sites with occupancy ratio of 72:28.

Figures

Fig. 1.
Molecular structure of the title compound, with the atom numbering scheme. The thermal ellipsoids are drawn at the 30% probability level. H-atoms are shown by small circles of arbitrary radii. The H atoms bonded to O1 and N1 show partial occupancy.
Fig. 2.
Crystal packing of the title compound.

Crystal data

0.61C19H17BrN4O3S·0.39C19H17BrN4O3SDx = 1.579 Mg m3
Mr = 461.34Melting point: 497 K
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 3428 reflections
a = 11.7919 (9) Åθ = 2.4–25.0°
b = 13.9965 (8) ŵ = 2.26 mm1
c = 23.5117 (17) ÅT = 296 K
V = 3880.5 (5) Å3Prismatic, red
Z = 80.20 × 0.16 × 0.14 mm
F(000) = 1872

Data collection

Bruker KAPPA APEXII CCD diffractometer3428 independent reflections
Radiation source: fine-focus sealed tube1961 reflections with I > 2σ(I)
graphiteRint = 0.081
Detector resolution: 7.9 pixels mm-1θmax = 25.0°, θmin = 2.4°
ω scansh = −14→14
Absorption correction: multi-scan (SADABS; Bruker, 2005)k = −16→16
Tmin = 0.650, Tmax = 0.725l = −27→26
19597 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.131H-atom parameters constrained
S = 1.00w = 1/[σ2(Fo2) + (0.057P)2 + 2.1678P] where P = (Fo2 + 2Fc2)/3
3428 reflections(Δ/σ)max = 0.001
257 parametersΔρmax = 0.35 e Å3
0 restraintsΔρmin = −0.65 e Å3

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.
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

xyzUiso*/UeqOcc. (<1)
Br11.18229 (5)0.76268 (4)0.36991 (3)0.0824 (3)
S10.40502 (9)0.37094 (8)0.60341 (5)0.0417 (3)
O10.9535 (3)0.3837 (2)0.39965 (16)0.0716 (11)
H1O0.91240.36920.42870.086*0.61 (7)
N10.8172 (3)0.4593 (3)0.46953 (16)0.0426 (9)
H1N0.86010.39680.45580.051*0.39 (7)
O20.3377 (3)0.3110 (2)0.56749 (13)0.0560 (9)
O30.3565 (2)0.4558 (2)0.62541 (13)0.0511 (8)
N20.4430 (3)0.2997 (2)0.65478 (15)0.0452 (10)
H2N0.41770.24210.65350.068*
N30.5374 (3)0.2497 (3)0.73414 (17)0.0472 (10)
N40.5447 (3)0.4138 (2)0.70529 (16)0.0458 (9)
C10.9643 (4)0.5482 (3)0.42496 (19)0.0440 (11)
C21.0200 (4)0.6363 (3)0.4176 (2)0.0493 (12)
H20.99660.68940.43830.059*
C31.1079 (4)0.6443 (3)0.3803 (2)0.0538 (13)
C41.1447 (4)0.5657 (4)0.3499 (2)0.0661 (15)
H41.20540.57160.32490.079*
C51.0922 (4)0.4790 (4)0.3565 (2)0.0685 (16)
H51.11680.42690.33520.082*
C61.0036 (4)0.4677 (3)0.3942 (2)0.0532 (13)
C70.8679 (4)0.5393 (3)0.46274 (19)0.0450 (11)
H70.84240.59270.48240.054*
C80.7198 (3)0.4440 (3)0.50347 (18)0.0375 (10)
C90.6759 (4)0.3538 (3)0.5027 (2)0.0538 (13)
H90.71070.30670.48090.065*
C100.5808 (4)0.3317 (3)0.5338 (2)0.0548 (13)
H100.55140.27010.53290.066*
C110.5290 (3)0.4005 (3)0.56628 (17)0.0359 (10)
C120.5738 (4)0.4917 (3)0.56843 (19)0.0430 (11)
H120.54050.53820.59120.052*
C130.6683 (4)0.5127 (3)0.5365 (2)0.0457 (12)
H130.69790.57430.53720.055*
C140.5124 (3)0.3231 (3)0.70054 (19)0.0417 (11)
C150.6020 (4)0.2704 (3)0.7790 (2)0.0523 (13)
C160.6396 (4)0.3624 (4)0.7881 (2)0.0579 (13)
H160.68500.37640.81930.069*
C170.6095 (4)0.4328 (3)0.7507 (2)0.0501 (12)
C180.6482 (5)0.5342 (4)0.7575 (3)0.0784 (17)
H18A0.68460.55500.72310.118*
H18B0.70090.53820.78850.118*
H18C0.58400.57430.76520.118*
C190.6307 (5)0.1897 (4)0.8188 (2)0.0797 (18)
H19A0.59730.13160.80500.120*0.72 (7)
H19B0.60150.20360.85600.120*0.72 (7)
H19C0.71150.18240.82080.120*0.72 (7)
H19D0.67620.21340.84950.120*0.28 (7)
H19E0.67200.14140.79850.120*0.28 (7)
H19F0.56200.16260.83370.120*0.28 (7)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Br10.0841 (5)0.0587 (4)0.1044 (6)−0.0198 (3)0.0112 (4)0.0058 (3)
S10.0396 (6)0.0417 (6)0.0437 (7)−0.0038 (5)−0.0033 (5)0.0005 (6)
O10.086 (3)0.0396 (19)0.089 (3)−0.0101 (18)0.039 (2)−0.0107 (19)
N10.044 (2)0.043 (2)0.041 (2)0.0041 (18)0.0030 (19)0.0006 (18)
O20.053 (2)0.060 (2)0.056 (2)−0.0146 (16)−0.0152 (17)−0.0017 (17)
O30.0480 (18)0.0495 (19)0.056 (2)0.0038 (15)0.0073 (16)−0.0015 (16)
N20.055 (2)0.039 (2)0.042 (2)−0.0141 (18)−0.010 (2)0.0017 (18)
N30.047 (2)0.051 (2)0.043 (3)0.0018 (18)−0.003 (2)0.000 (2)
N40.050 (2)0.046 (2)0.042 (3)−0.0097 (18)0.001 (2)−0.0051 (19)
C10.042 (3)0.049 (3)0.041 (3)0.005 (2)−0.006 (2)0.000 (2)
C20.056 (3)0.038 (3)0.054 (3)0.002 (2)−0.003 (3)−0.003 (2)
C30.043 (3)0.052 (3)0.066 (4)−0.003 (2)0.002 (3)0.006 (3)
C40.053 (3)0.060 (3)0.086 (4)0.002 (3)0.028 (3)−0.002 (3)
C50.063 (3)0.052 (3)0.091 (5)0.001 (3)0.031 (3)−0.010 (3)
C60.056 (3)0.041 (3)0.063 (4)0.003 (2)0.008 (3)−0.003 (3)
C70.051 (3)0.041 (3)0.044 (3)0.010 (2)0.000 (2)−0.002 (2)
C80.037 (2)0.043 (3)0.033 (3)0.004 (2)0.002 (2)0.001 (2)
C90.060 (3)0.044 (3)0.058 (3)0.002 (2)0.016 (3)−0.013 (2)
C100.059 (3)0.038 (3)0.067 (4)−0.006 (2)0.011 (3)−0.011 (2)
C110.040 (2)0.034 (2)0.034 (3)0.0019 (19)−0.004 (2)−0.0028 (19)
C120.050 (3)0.039 (3)0.040 (3)0.005 (2)0.008 (2)−0.007 (2)
C130.050 (3)0.035 (2)0.052 (3)−0.004 (2)0.006 (2)−0.006 (2)
C140.041 (3)0.048 (3)0.036 (3)−0.002 (2)0.004 (2)−0.001 (2)
C150.054 (3)0.057 (3)0.046 (3)0.016 (3)0.007 (3)−0.003 (3)
C160.046 (3)0.082 (4)0.046 (3)0.008 (3)−0.009 (2)−0.016 (3)
C170.043 (3)0.061 (3)0.046 (3)−0.005 (2)0.005 (2)−0.012 (3)
C180.085 (4)0.070 (4)0.081 (5)−0.031 (3)−0.002 (3)−0.020 (3)
C190.095 (4)0.083 (4)0.061 (4)0.035 (3)−0.016 (3)0.002 (3)

Geometric parameters (Å, °)

Br1—C31.890 (5)C7—H70.9300
S1—O31.416 (3)C8—C91.365 (6)
S1—O21.431 (3)C8—C131.378 (6)
S1—N21.629 (4)C9—C101.374 (6)
S1—C111.753 (4)C9—H90.9300
O1—C61.322 (5)C10—C111.372 (6)
O1—H1O0.8621C10—H100.9300
N1—C71.279 (5)C11—C121.381 (5)
N1—C81.414 (5)C12—C131.375 (6)
N1—H1N1.0611C12—H120.9300
N2—C141.391 (5)C13—H130.9300
N2—H2N0.8600C15—C161.378 (6)
N3—C141.329 (5)C15—C191.506 (7)
N3—C151.332 (6)C16—C171.368 (6)
N4—C141.330 (5)C16—H160.9300
N4—C171.339 (6)C17—C181.499 (6)
C1—C21.408 (6)C18—H18A0.9600
C1—C61.416 (6)C18—H18B0.9600
C1—C71.448 (6)C18—H18C0.9600
C2—C31.362 (6)C19—H19A0.9600
C2—H20.9300C19—H19B0.9600
C3—C41.382 (7)C19—H19C0.9600
C4—C51.371 (6)C19—H19D0.9600
C4—H40.9300C19—H19E0.9600
C5—C61.380 (7)C19—H19F0.9600
C5—H50.9300
O3—S1—O2118.9 (2)C11—C10—C9120.1 (4)
O3—S1—N2110.7 (2)C11—C10—H10120.0
O2—S1—N2103.37 (18)C9—C10—H10120.0
O3—S1—C11108.73 (19)C10—C11—C12119.9 (4)
O2—S1—C11107.90 (19)C10—C11—S1118.8 (3)
N2—S1—C11106.54 (18)C12—C11—S1121.3 (3)
C6—O1—H1O122.5C13—C12—C11119.2 (4)
C7—N1—C8125.7 (4)C13—C12—H12120.4
C7—N1—H1N117.4C11—C12—H12120.4
C8—N1—H1N115.7C12—C13—C8121.0 (4)
C14—N2—S1126.3 (3)C12—C13—H13119.5
C14—N2—H2N116.9C8—C13—H13119.5
S1—N2—H2N116.9N3—C14—N4128.6 (4)
C14—N3—C15115.4 (4)N3—C14—N2114.1 (4)
C14—N4—C17114.8 (4)N4—C14—N2117.2 (4)
C2—C1—C6118.8 (4)N3—C15—C16120.7 (5)
C2—C1—C7121.1 (4)N3—C15—C19117.2 (5)
C6—C1—C7120.1 (4)C16—C15—C19122.2 (5)
C3—C2—C1120.4 (4)C17—C16—C15119.3 (5)
C3—C2—H2119.8C17—C16—H16120.3
C1—C2—H2119.8C15—C16—H16120.3
C2—C3—C4120.4 (4)N4—C17—C16121.1 (4)
C2—C3—Br1120.6 (4)N4—C17—C18116.6 (5)
C4—C3—Br1119.0 (4)C16—C17—C18122.3 (5)
C5—C4—C3120.3 (5)C17—C18—H18A109.5
C5—C4—H4119.8C17—C18—H18B109.5
C3—C4—H4119.8H18A—C18—H18B109.5
C4—C5—C6121.1 (5)C17—C18—H18C109.5
C4—C5—H5119.5H18A—C18—H18C109.5
C6—C5—H5119.5H18B—C18—H18C109.5
O1—C6—C5120.2 (4)C15—C19—H19A109.5
O1—C6—C1120.8 (4)C15—C19—H19B109.5
C5—C6—C1119.0 (4)H19A—C19—H19B109.5
N1—C7—C1121.3 (4)C15—C19—H19C109.5
N1—C7—H7119.4H19A—C19—H19C109.5
C1—C7—H7119.4H19B—C19—H19C109.5
C9—C8—C13119.1 (4)C15—C19—H19D109.5
C9—C8—N1116.2 (4)C15—C19—H19E109.5
C13—C8—N1124.7 (4)H19D—C19—H19E109.5
C8—C9—C10120.7 (4)C15—C19—H19F109.5
C8—C9—H9119.6H19D—C19—H19F109.5
C10—C9—H9119.6H19E—C19—H19F109.5
O3—S1—N2—C14−53.3 (4)O3—S1—C11—C10−169.9 (4)
O2—S1—N2—C14178.3 (4)O2—S1—C11—C10−39.7 (4)
C11—S1—N2—C1464.7 (4)N2—S1—C11—C1070.8 (4)
C6—C1—C2—C31.9 (7)O3—S1—C11—C129.0 (4)
C7—C1—C2—C3−177.5 (4)O2—S1—C11—C12139.2 (3)
C1—C2—C3—C4−1.1 (7)N2—S1—C11—C12−110.4 (4)
C1—C2—C3—Br1179.6 (3)C10—C11—C12—C131.9 (7)
C2—C3—C4—C50.8 (8)S1—C11—C12—C13−177.0 (3)
Br1—C3—C4—C5−179.9 (4)C11—C12—C13—C8−1.3 (7)
C3—C4—C5—C6−1.4 (9)C9—C8—C13—C12−0.1 (7)
C4—C5—C6—O1179.4 (5)N1—C8—C13—C12−179.8 (4)
C4—C5—C6—C12.2 (8)C15—N3—C14—N41.1 (7)
C2—C1—C6—O1−179.6 (4)C15—N3—C14—N2−178.7 (4)
C7—C1—C6—O1−0.2 (7)C17—N4—C14—N3−1.1 (7)
C2—C1—C6—C5−2.4 (7)C17—N4—C14—N2178.7 (4)
C7—C1—C6—C5177.0 (5)S1—N2—C14—N3−175.0 (3)
C8—N1—C7—C1−177.3 (4)S1—N2—C14—N45.2 (6)
C2—C1—C7—N1180.0 (4)C14—N3—C15—C16−0.7 (6)
C6—C1—C7—N10.6 (7)C14—N3—C15—C19179.0 (4)
C7—N1—C8—C9177.0 (4)N3—C15—C16—C170.4 (7)
C7—N1—C8—C13−3.2 (7)C19—C15—C16—C17−179.3 (5)
C13—C8—C9—C100.8 (7)C14—N4—C17—C160.7 (6)
N1—C8—C9—C10−179.4 (4)C14—N4—C17—C18179.7 (4)
C8—C9—C10—C11−0.3 (7)C15—C16—C17—N4−0.4 (7)
C9—C10—C11—C12−1.1 (7)C15—C16—C17—C18−179.4 (5)
C9—C10—C11—S1177.8 (4)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N1—H1N···O11.061.732.530 (5)129
O1—H1O···N10.861.942.530 (5)124
N2—H2N···O1i0.862.202.871 (4)135
C9—H9···O2ii0.932.503.417 (5)169

Symmetry codes: (i) x−1/2, −y+1/2, −z+1; (ii) x+1/2, −y+1/2, −z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: GK2160).

References

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