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Acta Crystallogr Sect E Struct Rep Online. 2008 April 1; 64(Pt 4): o648.
Published online 2008 March 5. doi:  10.1107/S1600536808005606
PMCID: PMC2960946

4-(5-Chloro-2-hydroxy­benzyl­idene­amino)-N-(4,6-dimethyl­pyrimidin-2-yl)benzene­sulfonamide

Abstract

The title compound, C19H17ClN4O3S, is a Schiff base compound of 5-chloro­salicylaldehyde and sulfamethazine [4-amino-N-(4,6-dimethyl-2-pyrimidin­yl)benzene­sulfonamide]. The geometry around the S atom is distorted tetra­hedral, comprising two O atoms of the sulfonyl group, a C atom of a benzene ring and the amino N atom. The title compound has an intra­molecular O—H(...)N hydrogen bond and two inter­molecular C—H(...)O and N—H(...)O hydrogen bonds, which link neighbouring mol­ecules into 10-membered rings. As a result of an unavoidable conformational arrangement, a slightly short intra­molecular contact of distance 2.59 Å exists between an O atom of the sulfonyl group and an H atom of the sulfamethazine benzene ring.

Related literature

For related literature, see: Basak et al. (1983 [triangle]); Chohan & Shad (2007 [triangle]); Yang (2006 [triangle]); Shad et al. (2008 [triangle]); Zareef et al. (2007 [triangle]).

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Object name is e-64-0o648-scheme1.jpg

Experimental

Crystal data

  • C19H17ClN4O3S
  • M r = 416.88
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-64-0o648-efi1.jpg
  • a = 11.7332 (7) Å
  • b = 13.8506 (6) Å
  • c = 23.6635 (14) Å
  • V = 3845.6 (4) Å3
  • Z = 8
  • Mo Kα radiation radiation
  • μ = 0.34 mm−1
  • T = 296 (2) K
  • 0.22 × 0.18 × 0.14 mm

Data collection

  • Bruker Kappa APEXII CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2005 [triangle]) T min = 0.940, T max = 0.958
  • 21114 measured reflections
  • 4787 independent reflections
  • 2797 reflections with I > 2σ(I)
  • R int = 0.043

Refinement

  • R[F 2 > 2σ(F 2)] = 0.049
  • wR(F 2) = 0.148
  • S = 1.05
  • 2797 reflections
  • 259 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.32 e Å−3
  • Δρmin = −0.28 e Å−3

Data collection: APEX2 (Bruker, 2007 [triangle]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2007 [triangle]); 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 (Farrugia, 1999 [triangle]) and PLATON.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808005606/fj2100sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808005606/fj2100Isup2.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.

supplementary crystallographic information

Comment

Sulfonamides have widely been recognized for their wide variety of pharmacological activities such as antibacterial, antitumor, anti-carbonic anhydrase, diuretic, hypoglycaemic, antithyroid and protease inhibitory activity. Sulfonamides have also been used clinically as antimalarial agents (Zareef et al., 2007), particularly sulfadiazine and sulfadoxine. Due to their significant pharmacology applications and widespread use in medicine, these compounds have also gained attention in bio-inorganic and metal-based (Chohan et al., 2007) drug chemistry. In continuation to the preparation of schiff base ligands with various sulfa drugs and halogen substituated aldehydes (Shad et al., 2008), we report herein the structure of the title compound.

The title compound (I), is a Schiff base ligand containing sulfamethazine and 5-chlorosalicylaldehyde. The crystal structure (Basak et al., 1983) of (II) sulfamethazine:[4-amino-N-(4,6-dimethyl-2-pyrimidinyl)benzenesulfonamide] have been reported. The search in Cambridge Crystallographic Data Center showed that no crystal structure of 5-chlorosalicylaldehyde as an individual moiety is reported. Few structures containing the later have been reported such as 5-chlorosalicylaldehyde salicylhydrazone (Yang, 2006). The mutual effect of sulfamethazine and the 5-chlorosalicylaldehyde in solid form is observed by enlarging the bond lengths N1—C8 [1.414 (3) Å], S1—C11 [1.759 (3) Å] compared to 1.367 (3)° and 1.746 (3) Å respectively as reported in (II). The bond distances in the 4,6-dimethyl-2-pyrimidinyl moiety of sulfamethazine remained same whithin experimental errors. The observed bond angles C11—S1—N2 and S1—N2—C14 have values of 106.75 (13)°, 126.2 (2)° in comparison to 108.2 (1)° and 128.0 (2)° respectively. The torsion angle C11—S1—N2—C14: -64.3 (3)° in the title compound compared to 83.0 (3)° shows that the 4,6-dimethyl-2-pyrimidinyl moiety becomes almost in trans position. The observed change in 5-chlorosalicylaldehyde moiety, is mainly of bond distances C6—O1 [1.328 (4) Å] and Cl1—C5 [1.736 (3) Å], whereas these values are 1.347 (5) Å and 1.746 (4) Å as reported in 5-chlorosalicylaldehyde salicylhydrazone. The coordinates of H-atoms attached to O1 and N2 were refined. The rings A(C14/N3/C15/C16/C17/N4), B(C1/C2/C3/C4/C5/C6) and C(C8/C9/C10/C11/C12/C13), make dihedral angles A/B[78.95 (8)°], A/C[83.50 (8)°] and B/C[4.57 (19)°] respectively. The sulfonyl group (O2/S1/O3) have a dihedral angle of 56.36 (11)° with ring (B) and with ring (A), it is 54.25 (14)°. An intramolecular H-bond of O—H···N type complete six-membered ring, as shown in Fig 1. The two intermolecular H-bonds of C—H···O and N—H···O form a ten membered ring by sharing a six membered ring due to intramolecular H-bond as in Fig 2. The detail of H-bonds is given in Table 1.

Experimental

Sulfamethazine (0.5566 g, 2 mmol) in ethanol (15 ml) was reacted with ethanolic (10 ml) solution of 5-chlorosalicylaldehyde (0.3131 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 10 days crystals of the title compound were obtained.

Refinement

The coordinates of the hydroxy and amide H-atoms were freely refined. Other H-atoms were positioned geometrically, with C—H = 0.93 and 0.96 Å for aromatic and methyl carbons respectively. The Uiso(H) = xUeq(C, N, O), where x = 1.5 for methyl H, and x = 1.2 for all other H atoms.

Figures

Fig. 1.
ORTEP-3 for Windows (Farrugia, 1997) drawing of the title compound, C19H17Cl1N4O3S, with the atom numbering scheme. The thermal ellipsoids are drawn at the 50% probability level. H-atoms are shown by small circles of arbitrary radii. The intramolecular ...
Fig. 2.
The unit cell packing of (I) (Spek, 2003), showing the intermolecular hydrogen bonding completing a ten-membered ring.

Crystal data

C19H17ClN4O3SDx = 1.440 Mg m3
Mr = 416.88Melting point: 497 K
Orthorhombic, PbcaMo Kα radiation radiation λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 2797 reflections
a = 11.7332 (7) Åθ = 1.7–28.3º
b = 13.8506 (6) ŵ = 0.34 mm1
c = 23.6635 (14) ÅT = 296 (2) K
V = 3845.6 (4) Å3Prismatic, red
Z = 80.22 × 0.18 × 0.14 mm
F000 = 1728

Data collection

Bruker Kappa APEXII CCD diffractometer4787 independent reflections
Radiation source: fine-focus sealed tube2797 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.043
Detector resolution: 7.40 pixels mm-1θmax = 28.3º
T = 296(2) Kθmin = 1.7º
ω scansh = −15→15
Absorption correction: multi-scan(SADABS; Bruker, 2005)k = −17→18
Tmin = 0.940, Tmax = 0.958l = −31→30
21114 measured reflections

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.049H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.148  w = 1/[σ2(Fo2) + (0.0488P)2 + 2.8076P] where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max < 0.001
2797 reflectionsΔρmax = 0.32 e Å3
259 parametersΔρmin = −0.28 e Å3
Primary atom site location: structure-invariant direct methodsExtinction correction: none

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*/Ueq
Cl11.17644 (10)−0.26287 (7)−0.12764 (5)0.0872 (3)
S10.40720 (6)0.12989 (5)0.10363 (3)0.04261 (19)
O10.9575 (2)0.11270 (16)−0.10024 (12)0.0767 (8)
H10.902 (4)0.105 (3)−0.0865 (19)0.092*
O20.34086 (18)0.19106 (14)0.06787 (9)0.0566 (6)
O30.35672 (17)0.04443 (14)0.12555 (9)0.0533 (5)
N10.82013 (19)0.03779 (16)−0.03019 (10)0.0449 (6)
N20.4449 (2)0.20143 (17)0.15497 (11)0.0484 (6)
H20.442 (3)0.252 (2)0.1502 (14)0.058*
N30.5377 (2)0.25140 (17)0.23450 (10)0.0504 (6)
N40.5464 (2)0.08644 (17)0.20508 (10)0.0494 (6)
C10.9660 (2)−0.05366 (19)−0.07463 (12)0.0438 (6)
C21.0209 (3)−0.1429 (2)−0.08168 (13)0.0535 (8)
H2A0.9970−0.1960−0.06080.064*
C31.1091 (3)−0.1523 (2)−0.11879 (14)0.0546 (8)
C41.1463 (3)−0.0739 (2)−0.14968 (16)0.0685 (10)
H4A1.2067−0.0811−0.17480.082*
C51.0950 (3)0.0147 (2)−0.14375 (16)0.0703 (10)
H51.12020.0668−0.16510.084*
C61.0057 (3)0.0265 (2)−0.10596 (14)0.0543 (8)
C70.8701 (2)−0.0437 (2)−0.03688 (12)0.0479 (7)
H70.8442−0.0973−0.01710.058*
C80.7233 (2)0.05312 (19)0.00426 (11)0.0412 (6)
C90.6811 (3)0.1460 (2)0.00458 (14)0.0565 (8)
H90.71700.1935−0.01680.068*
C100.5868 (3)0.1695 (2)0.03601 (14)0.0561 (8)
H100.55970.23250.03640.067*
C110.5325 (2)0.09899 (18)0.06706 (11)0.0390 (6)
C120.5748 (2)0.00607 (19)0.06810 (12)0.0448 (7)
H120.5395−0.04090.09010.054*
C130.6696 (2)−0.01695 (19)0.03636 (12)0.0479 (7)
H130.6976−0.07980.03650.057*
C140.5142 (2)0.1773 (2)0.20062 (11)0.0432 (6)
C150.6017 (3)0.2304 (2)0.27940 (13)0.0577 (8)
C160.6394 (3)0.1374 (3)0.28828 (14)0.0631 (9)
H160.68410.12290.31960.076*
C170.6107 (3)0.0666 (2)0.25061 (14)0.0552 (8)
C180.6497 (3)−0.0362 (3)0.25674 (17)0.0825 (12)
H18A0.6198−0.07410.22620.124*
H18B0.6227−0.06180.29200.124*
H18C0.7314−0.03850.25600.124*
C190.6268 (4)0.3114 (3)0.31925 (16)0.0894 (13)
H19A0.59300.36980.30530.134*
H19B0.70780.31980.32230.134*
H19C0.59580.29660.35580.134*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Cl10.0896 (8)0.0611 (5)0.1110 (9)0.0210 (5)0.0139 (6)−0.0059 (5)
S10.0421 (4)0.0436 (4)0.0421 (4)0.0046 (3)−0.0031 (3)0.0001 (3)
O10.0854 (19)0.0453 (12)0.099 (2)0.0069 (12)0.0452 (16)0.0174 (12)
O20.0549 (13)0.0587 (12)0.0562 (13)0.0154 (10)−0.0166 (10)0.0013 (10)
O30.0474 (12)0.0526 (11)0.0601 (13)−0.0030 (9)0.0087 (10)0.0007 (10)
N10.0447 (13)0.0476 (13)0.0424 (14)−0.0036 (11)0.0031 (11)−0.0003 (10)
N20.0594 (16)0.0417 (12)0.0442 (14)0.0095 (12)−0.0076 (12)−0.0026 (11)
N30.0539 (15)0.0534 (14)0.0440 (14)−0.0051 (12)−0.0003 (12)−0.0005 (11)
N40.0525 (15)0.0515 (14)0.0442 (14)0.0134 (11)−0.0001 (11)0.0037 (11)
C10.0435 (16)0.0447 (14)0.0433 (16)−0.0046 (12)−0.0021 (13)−0.0001 (12)
C20.060 (2)0.0440 (15)0.0562 (19)−0.0030 (14)0.0014 (15)0.0036 (14)
C30.0499 (18)0.0502 (16)0.064 (2)0.0036 (14)0.0001 (15)−0.0047 (14)
C40.056 (2)0.068 (2)0.081 (3)0.0001 (17)0.0257 (18)−0.0003 (19)
C50.068 (2)0.0556 (19)0.087 (3)−0.0026 (17)0.030 (2)0.0141 (18)
C60.0564 (19)0.0460 (16)0.060 (2)−0.0028 (14)0.0102 (16)0.0026 (14)
C70.0500 (17)0.0491 (15)0.0447 (16)−0.0117 (13)−0.0008 (14)0.0043 (13)
C80.0442 (15)0.0434 (14)0.0360 (14)−0.0049 (12)0.0003 (12)−0.0006 (12)
C90.063 (2)0.0436 (16)0.063 (2)−0.0043 (14)0.0172 (16)0.0136 (14)
C100.065 (2)0.0387 (14)0.064 (2)0.0033 (14)0.0120 (17)0.0105 (14)
C110.0428 (15)0.0409 (13)0.0334 (14)−0.0002 (11)−0.0030 (11)0.0017 (11)
C120.0522 (17)0.0375 (14)0.0446 (16)−0.0021 (12)0.0090 (13)0.0071 (12)
C130.0533 (18)0.0386 (14)0.0517 (18)0.0031 (12)0.0073 (14)0.0044 (13)
C140.0405 (15)0.0512 (16)0.0378 (15)0.0043 (13)0.0040 (12)0.0023 (12)
C150.0516 (19)0.076 (2)0.0454 (18)−0.0206 (16)−0.0016 (15)0.0042 (16)
C160.0472 (18)0.093 (2)0.0489 (19)−0.0113 (17)−0.0124 (15)0.0199 (18)
C170.0459 (17)0.0693 (19)0.0504 (18)0.0065 (15)0.0032 (14)0.0173 (16)
C180.081 (3)0.081 (2)0.086 (3)0.026 (2)−0.007 (2)0.027 (2)
C190.105 (3)0.096 (3)0.068 (2)−0.046 (3)−0.019 (2)−0.004 (2)

Geometric parameters (Å, °)

Cl1—C31.736 (3)C5—H50.9300
S1—O31.422 (2)C7—H70.9300
S1—O21.4282 (19)C8—C91.379 (4)
S1—N21.629 (3)C8—C131.384 (4)
S1—C111.759 (3)C9—C101.371 (4)
O1—C61.328 (4)C9—H90.9300
O1—H10.74 (4)C10—C111.378 (4)
N1—C71.282 (4)C10—H100.9300
N1—C81.414 (3)C11—C121.379 (3)
N2—C141.393 (4)C12—C131.380 (4)
N2—H20.71 (3)C12—H120.9300
N3—C141.332 (3)C13—H130.9300
N3—C151.333 (4)C15—C161.378 (5)
N4—C141.318 (3)C15—C191.495 (5)
N4—C171.343 (4)C16—C171.368 (5)
C1—C21.404 (4)C16—H160.9300
C1—C61.414 (4)C17—C181.503 (4)
C1—C71.443 (4)C18—H18A0.9600
C2—C31.363 (4)C18—H18B0.9600
C2—H2A0.9300C18—H18C0.9600
C3—C41.380 (4)C19—H19A0.9600
C4—C51.373 (4)C19—H19B0.9600
C4—H4A0.9300C19—H19C0.9600
C5—C61.388 (4)
O3—S1—O2118.89 (13)C10—C9—H9119.6
O3—S1—N2110.33 (13)C8—C9—H9119.6
O2—S1—N2103.22 (12)C9—C10—C11119.6 (3)
O3—S1—C11108.98 (12)C9—C10—H10120.2
O2—S1—C11107.97 (13)C11—C10—H10120.2
N2—S1—C11106.75 (13)C10—C11—C12120.3 (3)
C6—O1—H1107 (3)C10—C11—S1118.5 (2)
C7—N1—C8124.8 (2)C12—C11—S1121.3 (2)
C14—N2—S1126.2 (2)C11—C12—C13119.7 (2)
C14—N2—H2113 (3)C11—C12—H12120.1
S1—N2—H2118 (3)C13—C12—H12120.1
C14—N3—C15115.3 (3)C12—C13—C8120.2 (3)
C14—N4—C17114.9 (3)C12—C13—H13119.9
C2—C1—C6118.5 (3)C8—C13—H13119.9
C2—C1—C7121.1 (3)N4—C14—N3128.9 (3)
C6—C1—C7120.4 (3)N4—C14—N2117.3 (3)
C3—C2—C1120.6 (3)N3—C14—N2113.8 (2)
C3—C2—H2A119.7N3—C15—C16120.5 (3)
C1—C2—H2A119.7N3—C15—C19116.7 (3)
C2—C3—C4120.4 (3)C16—C15—C19122.8 (3)
C2—C3—Cl1120.5 (2)C17—C16—C15119.4 (3)
C4—C3—Cl1119.1 (3)C17—C16—H16120.3
C5—C4—C3120.7 (3)C15—C16—H16120.3
C5—C4—H4A119.7N4—C17—C16120.9 (3)
C3—C4—H4A119.7N4—C17—C18116.3 (3)
C4—C5—C6120.1 (3)C16—C17—C18122.8 (3)
C4—C5—H5119.9C17—C18—H18A109.5
C6—C5—H5119.9C17—C18—H18B109.5
O1—C6—C5119.5 (3)H18A—C18—H18B109.5
O1—C6—C1120.8 (3)C17—C18—H18C109.5
C5—C6—C1119.6 (3)H18A—C18—H18C109.5
N1—C7—C1121.2 (3)H18B—C18—H18C109.5
N1—C7—H7119.4C15—C19—H19A109.5
C1—C7—H7119.4C15—C19—H19B109.5
C9—C8—C13119.2 (3)H19A—C19—H19B109.5
C9—C8—N1115.6 (2)C15—C19—H19C109.5
C13—C8—N1125.2 (2)H19A—C19—H19C109.5
C10—C9—C8120.9 (3)H19B—C19—H19C109.5
O3—S1—N2—C1454.0 (3)O3—S1—C11—C10171.4 (2)
O2—S1—N2—C14−178.0 (3)O2—S1—C11—C1041.0 (3)
C11—S1—N2—C14−64.3 (3)N2—S1—C11—C10−69.4 (3)
C6—C1—C2—C3−1.3 (4)O3—S1—C11—C12−7.1 (3)
C7—C1—C2—C3177.9 (3)O2—S1—C11—C12−137.5 (2)
C1—C2—C3—C40.6 (5)N2—S1—C11—C12112.0 (2)
C1—C2—C3—Cl1−179.7 (2)C10—C11—C12—C13−2.2 (4)
C2—C3—C4—C5−0.3 (6)S1—C11—C12—C13176.3 (2)
Cl1—C3—C4—C5−180.0 (3)C11—C12—C13—C81.0 (4)
C3—C4—C5—C60.7 (6)C9—C8—C13—C120.2 (4)
C4—C5—C6—O1179.4 (4)N1—C8—C13—C12−179.4 (3)
C4—C5—C6—C1−1.5 (6)C17—N4—C14—N30.9 (4)
C2—C1—C6—O1−179.1 (3)C17—N4—C14—N2−178.4 (3)
C7—C1—C6—O11.7 (5)C15—N3—C14—N4−0.9 (4)
C2—C1—C6—C51.8 (5)C15—N3—C14—N2178.4 (3)
C7—C1—C6—C5−177.4 (3)S1—N2—C14—N4−4.9 (4)
C8—N1—C7—C1177.5 (2)S1—N2—C14—N3175.7 (2)
C2—C1—C7—N1179.7 (3)C14—N3—C15—C160.4 (4)
C6—C1—C7—N1−1.1 (4)C14—N3—C15—C19−178.2 (3)
C7—N1—C8—C9−178.6 (3)N3—C15—C16—C17−0.1 (5)
C7—N1—C8—C131.1 (4)C19—C15—C16—C17178.4 (3)
C13—C8—C9—C10−0.2 (5)C14—N4—C17—C16−0.5 (4)
N1—C8—C9—C10179.4 (3)C14—N4—C17—C18−179.5 (3)
C8—C9—C10—C11−0.9 (5)C15—C16—C17—N40.2 (5)
C9—C10—C11—C122.2 (5)C15—C16—C17—C18179.1 (3)
C9—C10—C11—S1−176.4 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O1—H1···N10.73 (5)1.90 (4)2.534 (3)146 (5)
N2—H2···O1i0.71 (3)2.22 (3)2.886 (3)156 (3)
C9—H9···O2ii0.932.483.398 (4)171

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: FJ2100).

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