organic compounds
4-Amino-N-(3-methoxypyrazin-2-yl)benzenesulfonamide
aDipartimento di Scienze Farmaceutiche, Universitá di Firenze, Via U. Schiff 6, I-50019 Sesto Fiorentino, Firenze, Italy, and bDipartimento di Chimica, Universitá di Firenze, Via della Lastruccia 3, I-50019 Sesto Fiorentino, Firenze, Italy
*Correspondence e-mail: massimo.divaira@unifi.it
The overall molecular geometry of the title compound, C11H12N4O3S, is bent, with a dihedral angle of 89.24 (5)° between the best planes through the two aromatic rings. Each molecule behaves as a hydrogen-bond donor toward three different molecules, through its amidic and the two aminic H atoms, and it behaves as a hydrogen-bond acceptor from two other molecules via one of its sulfonamidic O atoms. In the crystal, molecules linked by N—H⋯N and N—H⋯O hydrogen bonds form kinked layers parallel to (001), adjacent layers being connected by van der Waals interactions.
Related literature
The title compound is a prolonged-action drug known as sulfamethoxypyrazine or sulfalene, traditionally used for the treatment of urinary tract infections and chronic bronchitis. It is also presently employed in combination with other drugs for the treatment of malaria and other diseases. For the pharmacological applications of the title compound, see: Adam & Hagelnur (2009); Penali & Jansen (2008). For the structure of a related anticancer drug, see: Liu et al. (1994). For hydrogen-bond motifs, see: Bernstein et al. (1995).
Experimental
Crystal data
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Refinement
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Data collection: CrysAlis PRO CCD (Oxford Diffraction, 2006); cell CrysAlis PRO CCD; data reduction: CrysAlis PRO RED (Oxford Diffraction, 2006); program(s) used to solve structure: SIR2004 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97, WinGX (Farrugia, 1999) and PARST (Nardelli, 1995).
Supporting information
10.1107/S1600536810038158/fl2318sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536810038158/fl2318Isup2.hkl
Samples of I were kindly provided by SIMS (SIMS srl, Reggello, Firenze, Italy). Crystals of the compound, suitable for X-ray
were obtained by slow evaporation from 1:1 ethanol:butanol solutions.In the final
cycles non-hydrogen atoms were assigned anisotropic thermal parameters and H atoms had Uiso(H) = 1.2 Ueq(C, N), or Uiso(H) = 1.5 Ueq(C) for methyl H atoms. Hydrogen atoms were placed in geometrically generated positions, riding, except for those linked to nitrogen atoms, whose positions were allowed to refine (final values: 0.85 (2) Å for amidic N—H and 0.90 (3)–0.91 (3) Å range for aminic N—H bonds), and for the methyl H atoms, which were refined as part of a group with idealized geometry, freely rotating about the C—C bond. Assigned C—H: aromatic CH 0.950 Å; primary CH 0.952 Å.Data collection: CrysAlis PRO CCD (Oxford Diffraction, 2006); cell
CrysAlis PRO CCD (Oxford Diffraction, 2006); data reduction: CrysAlis PRO RED (Oxford Diffraction, 2006); program(s) used to solve structure: SIR2004 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), WinGX (Farrugia, 1999) and PARST (Nardelli, 1995).C11H12N4O3S | F(000) = 1168 |
Mr = 280.31 | Dx = 1.473 Mg m−3 |
Orthorhombic, Pbca | Cu Kα radiation, λ = 1.54180 Å |
Hall symbol: -P 2ac 2ab | Cell parameters from 4106 reflections |
a = 10.7589 (2) Å | θ = 4.5–71.1° |
b = 9.5652 (2) Å | µ = 2.40 mm−1 |
c = 24.5586 (4) Å | T = 150 K |
V = 2527.35 (8) Å3 | Elongated prism, colourless |
Z = 8 | 0.60 × 0.10 × 0.10 mm |
Oxford Diffraction Xcalibur PX Ultra CCD diffractometer | 2373 independent reflections |
Radiation source: fine-focus sealed tube | 2103 reflections with I > 2σ(I) |
Oxford Diffraction, Enhance ULTRA assembly monochromator | Rint = 0.016 |
Detector resolution: 8.1241 pixels mm-1 | θmax = 71.2°, θmin = 5.5° |
ω scans | h = −8→12 |
Absorption correction: multi-scan (ABSPACK; Oxford Diffraction, 2006) | k = −7→11 |
Tmin = 0.477, Tmax = 1.000 | l = −28→29 |
5771 measured reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.032 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.103 | w = 1/[σ2(Fo2) + (0.0536P)2 + 1.4166P] where P = (Fo2 + 2Fc2)/3 |
S = 1.14 | (Δ/σ)max = 0.001 |
2373 reflections | Δρmax = 0.29 e Å−3 |
184 parameters | Δρmin = −0.41 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.00110 (16) |
C11H12N4O3S | V = 2527.35 (8) Å3 |
Mr = 280.31 | Z = 8 |
Orthorhombic, Pbca | Cu Kα radiation |
a = 10.7589 (2) Å | µ = 2.40 mm−1 |
b = 9.5652 (2) Å | T = 150 K |
c = 24.5586 (4) Å | 0.60 × 0.10 × 0.10 mm |
Oxford Diffraction Xcalibur PX Ultra CCD diffractometer | 2373 independent reflections |
Absorption correction: multi-scan (ABSPACK; Oxford Diffraction, 2006) | 2103 reflections with I > 2σ(I) |
Tmin = 0.477, Tmax = 1.000 | Rint = 0.016 |
5771 measured reflections |
R[F2 > 2σ(F2)] = 0.032 | 0 restraints |
wR(F2) = 0.103 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.14 | Δρmax = 0.29 e Å−3 |
2373 reflections | Δρmin = −0.41 e Å−3 |
184 parameters |
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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. |
x | y | z | Uiso*/Ueq | ||
S | 0.45913 (4) | 0.21136 (4) | 0.376497 (16) | 0.01994 (17) | |
O1 | 0.59274 (13) | 0.21818 (13) | 0.37730 (5) | 0.0254 (3) | |
O2 | 0.40093 (12) | 0.07918 (13) | 0.38690 (5) | 0.0263 (3) | |
N3 | 0.40614 (15) | 0.31297 (15) | 0.42568 (6) | 0.0221 (3) | |
H3N | 0.340 (2) | 0.283 (2) | 0.4404 (9) | 0.026* | |
C1 | 0.42548 (17) | 0.45781 (18) | 0.42714 (7) | 0.0217 (4) | |
C2 | 0.34037 (17) | 0.53944 (18) | 0.45771 (7) | 0.0214 (4) | |
N1 | 0.34155 (15) | 0.67589 (16) | 0.45622 (6) | 0.0258 (4) | |
C3 | 0.43419 (19) | 0.7358 (2) | 0.42669 (8) | 0.0299 (4) | |
H3 | 0.4377 | 0.8347 | 0.4239 | 0.036* | |
C4 | 0.52204 (19) | 0.6575 (2) | 0.40095 (9) | 0.0321 (5) | |
H4 | 0.5885 | 0.7035 | 0.3828 | 0.039* | |
N2 | 0.51757 (14) | 0.51529 (17) | 0.40040 (7) | 0.0272 (4) | |
O3 | 0.25850 (12) | 0.46696 (12) | 0.48767 (5) | 0.0255 (3) | |
C5 | 0.1764 (2) | 0.5454 (2) | 0.52249 (8) | 0.0326 (5) | |
H51 | 0.1171 (12) | 0.5941 (15) | 0.5008 (3) | 0.049* | |
H52 | 0.2235 (7) | 0.6108 (14) | 0.5432 (5) | 0.049* | |
H53 | 0.1343 (12) | 0.4832 (9) | 0.5465 (5) | 0.049* | |
C6 | 0.40661 (16) | 0.27630 (17) | 0.31414 (7) | 0.0209 (4) | |
C7 | 0.47006 (16) | 0.3858 (2) | 0.28819 (8) | 0.0242 (4) | |
H7 | 0.5409 | 0.4267 | 0.3049 | 0.029* | |
C8 | 0.42941 (17) | 0.43368 (19) | 0.23848 (7) | 0.0252 (4) | |
H8 | 0.4723 | 0.5083 | 0.2212 | 0.030* | |
C9 | 0.32573 (16) | 0.37426 (18) | 0.21290 (7) | 0.0230 (4) | |
C10 | 0.26457 (17) | 0.2631 (2) | 0.23915 (7) | 0.0262 (4) | |
H10 | 0.1953 | 0.2201 | 0.2220 | 0.031* | |
C11 | 0.30361 (17) | 0.21565 (18) | 0.28935 (8) | 0.0250 (4) | |
H11 | 0.2603 | 0.1418 | 0.3069 | 0.030* | |
N4 | 0.28793 (16) | 0.42195 (19) | 0.16322 (6) | 0.0282 (4) | |
H41 | 0.321 (2) | 0.501 (3) | 0.1502 (10) | 0.034* | |
H42 | 0.219 (2) | 0.387 (2) | 0.1469 (10) | 0.034* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S | 0.0234 (3) | 0.0165 (2) | 0.0200 (2) | 0.00331 (15) | 0.00297 (15) | 0.00145 (15) |
O1 | 0.0264 (7) | 0.0259 (7) | 0.0240 (7) | 0.0062 (5) | 0.0027 (5) | 0.0034 (5) |
O2 | 0.0363 (8) | 0.0165 (6) | 0.0262 (6) | 0.0009 (5) | 0.0048 (6) | 0.0012 (5) |
N3 | 0.0267 (8) | 0.0169 (7) | 0.0225 (7) | −0.0006 (6) | 0.0063 (6) | −0.0002 (6) |
C1 | 0.0259 (9) | 0.0183 (8) | 0.0209 (8) | −0.0016 (7) | −0.0015 (7) | 0.0012 (7) |
C2 | 0.0265 (9) | 0.0189 (8) | 0.0189 (8) | −0.0013 (7) | −0.0027 (7) | 0.0007 (7) |
N1 | 0.0320 (8) | 0.0175 (7) | 0.0278 (8) | −0.0020 (6) | −0.0023 (6) | −0.0015 (6) |
C3 | 0.0345 (10) | 0.0197 (9) | 0.0353 (10) | −0.0051 (8) | −0.0028 (8) | −0.0001 (8) |
C4 | 0.0319 (10) | 0.0261 (10) | 0.0385 (11) | −0.0091 (8) | 0.0046 (8) | 0.0001 (9) |
N2 | 0.0278 (8) | 0.0221 (8) | 0.0316 (9) | −0.0051 (6) | 0.0046 (7) | −0.0007 (7) |
O3 | 0.0325 (7) | 0.0194 (6) | 0.0244 (6) | 0.0011 (5) | 0.0081 (5) | −0.0001 (5) |
C5 | 0.0431 (12) | 0.0291 (10) | 0.0255 (9) | 0.0060 (9) | 0.0122 (9) | −0.0003 (8) |
C6 | 0.0233 (9) | 0.0178 (8) | 0.0216 (9) | 0.0022 (6) | 0.0021 (7) | 0.0015 (7) |
C7 | 0.0220 (9) | 0.0251 (9) | 0.0255 (9) | −0.0018 (7) | −0.0018 (7) | 0.0021 (8) |
C8 | 0.0249 (9) | 0.0249 (9) | 0.0258 (9) | −0.0021 (7) | 0.0008 (7) | 0.0048 (8) |
C9 | 0.0241 (9) | 0.0228 (9) | 0.0222 (8) | 0.0029 (7) | 0.0010 (7) | −0.0001 (7) |
C10 | 0.0255 (9) | 0.0246 (9) | 0.0285 (9) | −0.0037 (8) | −0.0027 (8) | −0.0002 (8) |
C11 | 0.0263 (9) | 0.0205 (9) | 0.0282 (9) | −0.0013 (7) | 0.0019 (7) | 0.0027 (7) |
N4 | 0.0276 (8) | 0.0325 (9) | 0.0247 (8) | −0.0050 (7) | −0.0044 (7) | 0.0057 (7) |
S—O2 | 1.4338 (13) | C5—H51 | 0.9522 |
S—O1 | 1.4392 (14) | C5—H52 | 0.9522 |
S—N3 | 1.6519 (15) | C5—H53 | 0.9522 |
S—C6 | 1.7466 (17) | C6—C11 | 1.391 (3) |
N3—C1 | 1.401 (2) | C6—C7 | 1.403 (3) |
N3—H3N | 0.85 (2) | C7—C8 | 1.375 (3) |
C1—N2 | 1.310 (2) | C7—H7 | 0.9500 |
C1—C2 | 1.418 (3) | C8—C9 | 1.401 (3) |
C2—N1 | 1.306 (2) | C8—H8 | 0.9500 |
C2—O3 | 1.341 (2) | C9—N4 | 1.365 (2) |
N1—C3 | 1.359 (3) | C9—C10 | 1.407 (3) |
C3—C4 | 1.361 (3) | C10—C11 | 1.379 (3) |
C3—H3 | 0.9500 | C10—H10 | 0.9500 |
C4—N2 | 1.361 (3) | C11—H11 | 0.9500 |
C4—H4 | 0.9500 | N4—H41 | 0.90 (3) |
O3—C5 | 1.440 (2) | N4—H42 | 0.91 (3) |
O2—S—O1 | 118.28 (8) | H51—C5—H52 | 109.5 |
O2—S—N3 | 103.76 (8) | O3—C5—H53 | 109.5 |
O1—S—N3 | 107.94 (8) | H51—C5—H53 | 109.5 |
O2—S—C6 | 109.19 (8) | H52—C5—H53 | 109.5 |
O1—S—C6 | 108.60 (8) | C11—C6—C7 | 120.01 (16) |
N3—S—C6 | 108.68 (8) | C11—C6—S | 119.54 (13) |
C1—N3—S | 123.30 (13) | C7—C6—S | 120.41 (14) |
C1—N3—H3N | 116.6 (15) | C8—C7—C6 | 119.81 (17) |
S—N3—H3N | 113.7 (15) | C8—C7—H7 | 120.1 |
N2—C1—N3 | 120.97 (16) | C6—C7—H7 | 120.1 |
N2—C1—C2 | 121.51 (16) | C7—C8—C9 | 121.07 (17) |
N3—C1—C2 | 117.51 (16) | C7—C8—H8 | 119.5 |
N1—C2—O3 | 122.59 (16) | C9—C8—H8 | 119.5 |
N1—C2—C1 | 121.94 (17) | N4—C9—C8 | 120.18 (17) |
O3—C2—C1 | 115.46 (15) | N4—C9—C10 | 121.54 (17) |
C2—N1—C3 | 116.31 (17) | C8—C9—C10 | 118.27 (16) |
N1—C3—C4 | 121.68 (18) | C11—C10—C9 | 121.07 (17) |
N1—C3—H3 | 119.2 | C11—C10—H10 | 119.5 |
C4—C3—H3 | 119.2 | C9—C10—H10 | 119.5 |
N2—C4—C3 | 121.98 (18) | C10—C11—C6 | 119.76 (17) |
N2—C4—H4 | 119.0 | C10—C11—H11 | 120.1 |
C3—C4—H4 | 119.0 | C6—C11—H11 | 120.1 |
C1—N2—C4 | 116.19 (17) | C9—N4—H41 | 118.9 (15) |
C2—O3—C5 | 117.34 (14) | C9—N4—H42 | 121.1 (15) |
O3—C5—H51 | 109.5 | H41—N4—H42 | 118 (2) |
O3—C5—H52 | 109.5 | ||
O2—S—N3—C1 | −170.84 (15) | C1—C2—O3—C5 | 175.49 (16) |
O1—S—N3—C1 | 62.86 (16) | O2—S—C6—C11 | 13.30 (17) |
C6—S—N3—C1 | −54.74 (17) | O1—S—C6—C11 | 143.57 (14) |
S—N3—C1—N2 | −22.2 (2) | N3—S—C6—C11 | −99.25 (15) |
S—N3—C1—C2 | 156.57 (13) | O2—S—C6—C7 | −164.57 (14) |
N2—C1—C2—N1 | 7.2 (3) | O1—S—C6—C7 | −34.30 (17) |
N3—C1—C2—N1 | −171.57 (16) | N3—S—C6—C7 | 82.88 (16) |
N2—C1—C2—O3 | −173.32 (16) | C11—C6—C7—C8 | 0.6 (3) |
N3—C1—C2—O3 | 7.9 (2) | S—C6—C7—C8 | 178.47 (14) |
O3—C2—N1—C3 | 176.25 (16) | C6—C7—C8—C9 | −0.5 (3) |
C1—C2—N1—C3 | −4.4 (3) | C7—C8—C9—N4 | −179.05 (17) |
C2—N1—C3—C4 | −1.1 (3) | C7—C8—C9—C10 | −0.5 (3) |
N1—C3—C4—N2 | 4.3 (3) | N4—C9—C10—C11 | 179.95 (17) |
N3—C1—N2—C4 | 174.85 (17) | C8—C9—C10—C11 | 1.5 (3) |
C2—C1—N2—C4 | −3.9 (3) | C9—C10—C11—C6 | −1.3 (3) |
C3—C4—N2—C1 | −1.5 (3) | C7—C6—C11—C10 | 0.3 (3) |
N1—C2—O3—C5 | −5.1 (2) | S—C6—C11—C10 | −177.59 (14) |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3N···N1i | 0.85 (2) | 2.24 (2) | 3.063 (2) | 164 (2) |
N4—H42···O1ii | 0.91 (3) | 2.19 (3) | 3.033 (2) | 154 (2) |
N4—H41···O1iii | 0.90 (3) | 2.37 (3) | 3.266 (2) | 176 (2) |
Symmetry codes: (i) −x+1/2, y−1/2, z; (ii) x−1/2, y, −z+1/2; (iii) −x+1, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C11H12N4O3S |
Mr | 280.31 |
Crystal system, space group | Orthorhombic, Pbca |
Temperature (K) | 150 |
a, b, c (Å) | 10.7589 (2), 9.5652 (2), 24.5586 (4) |
V (Å3) | 2527.35 (8) |
Z | 8 |
Radiation type | Cu Kα |
µ (mm−1) | 2.40 |
Crystal size (mm) | 0.60 × 0.10 × 0.10 |
Data collection | |
Diffractometer | Oxford Diffraction Xcalibur PX Ultra CCD diffractometer |
Absorption correction | Multi-scan (ABSPACK; Oxford Diffraction, 2006) |
Tmin, Tmax | 0.477, 1.000 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 5771, 2373, 2103 |
Rint | 0.016 |
(sin θ/λ)max (Å−1) | 0.614 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.032, 0.103, 1.14 |
No. of reflections | 2373 |
No. of parameters | 184 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.29, −0.41 |
Computer programs: CrysAlis PRO CCD (Oxford Diffraction, 2006), CrysAlis PRO RED (Oxford Diffraction, 2006), SIR2004 (Burla et al., 2005), ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009), SHELXL97 (Sheldrick, 2008), WinGX (Farrugia, 1999) and PARST (Nardelli, 1995).
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3N···N1i | 0.85 (2) | 2.24 (2) | 3.063 (2) | 164 (2) |
N4—H42···O1ii | 0.91 (3) | 2.19 (3) | 3.033 (2) | 154 (2) |
N4—H41···O1iii | 0.90 (3) | 2.37 (3) | 3.266 (2) | 176 (2) |
Symmetry codes: (i) −x+1/2, y−1/2, z; (ii) x−1/2, y, −z+1/2; (iii) −x+1, y+1/2, −z+1/2. |
Acknowledgements
The authors acknowledge financial support from the Italian Ministero dell'Istruzione, dell'Universitá e della Ricerca. The availability of diffraction facilities at the CRIST Centre of the University of Florence is also acknowledged.
References
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This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
The title compound (I), a drug known as sulfamethoxypyrazine or sulfalene, has been in use for a long time in the treatment of urinary tract infections and chronic bronchitis. Recently, due to the onset of Plasmodium falciparum resistance to many antimalarial drugs (e.g. chloroquine), the use of sulfamethoxypyrazine in combination with the dihydrofolate reductase inhibitor pyrimethamine has acquired great importance (Penali & Jansen, 2008). These formulations are also being tested against other deseases, like cutaneous leishmaniasis (Adam & Hagelnur, 2009).
In the structure of I there is one molecule of the title compound in the asymmetric unit of the orthorhombic unit cell. As a consequence of the arrangement of bonds around the sulfur atom, the overall molecular geometry is bent (Fig. 1), with an 89.24 (5) ° angle between the best planes through the two aromatic rings. The amidic N—H bond is almost parallel to the pyrazine plane, the H atom deviating by 0.28 (2) Å from that plane, and the plane of the aminic group is almost parallel to that of the phenyl ring, forming a 12 (2) ° angle with it. Each molecule behaves as a hydrogen bond donor toward three different molecules, through its amidic and the two aminic H atoms, and it behaves as a hydrogen bond acceptor from two other molecules via one of its sulfonamidic O atoms. The N—H···N and N—H···O interactions generate, respectively, a C(5) motif and a C21(4) binary graph set (Bernstein et al., 1995). Kinked layers of hydrogen–bonded molecules parallel to (001) are formed (Fig. 2), with no additional hydrogen bond interactions between layers. The structure of a somewhat related anticancer drug has been reported (Liu et al., 1994).