organic compounds
N-(4-Bromophenyl)pyrazine-2-carboxamide
aFundaçao Oswaldo Cruz, Instituto de Tecnologia em Fármacos - Farmanguinhos, R. Sizenando Nabuco 100, Manguinhos, 21041-250 Rio de Janeiro, RJ, Brazil, bCHEMSOL, 1 Harcourt Road, Aberdeen AB15 5NY, Scotland, cCentro de Desenvolvimento Tecnológico em Saúde (CDTS), Fundação Oswaldo Cruz (FIOCRUZ), Casa Amarela, Campus de Manguinhos, Avenida Brasil 4365, 21040-900 Rio de Janeiro, RJ, Brazil, and dDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: edward.tiekink@gmail.com
The molecule of the title compound, C11H8BrN3O, is close to planar (r.m.s. deviation of all 16 non-H atoms = 0.103 Å), a conformation stabilized by an intramolecular N—H⋯N hydrogen bond, which generates an S(5) ring. In the supramolecular chains mediated by C—H⋯O contacts (along a) are linked into a double layer via N⋯Br halogen bonds [3.207 (5) Å] and C—Br⋯π interactions [Br⋯ring centroid(pyrazine) = 3.446 (3) Å]. The layers stack along the b axis via weak π–π interactions [ring centroid(pyrazine)⋯ring centroid(benzene) distance = 3.803 (4) Å].
Related literature
For the antimycobacterial activity of pyrazinamide, see: Chaisson et al. (2002); Gordin et al. (2000); de Souza (2006). For structural studies of pyrazinamide derivatives; see: Baddeley et al. (2009); Howie et al. (2010a,b,c,d). For the synthesis, see: Wardell et al. (2008); Vontor et al. (1989). For background to halogen bonding, see: Metrangolo et al. (2008); Pennington et al. (2008). For graph-set nomenclature of hydrogen bonds, see: Bernstein et al. (1995). For details of software used to analyse the shape of the molecule, see: Spek (2009).
Experimental
Crystal data
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Refinement
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Data collection: COLLECT (Nonius, 1998); cell DENZO (Otwinowski & Minor, 1997) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).
Supporting information
https://doi.org/10.1107/S1600536810039036/hb5661sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810039036/hb5661Isup2.hkl
N-(4-Bromophenyl)pyrazine-2-carboxamide was prepared following the general procedure for N-arylpyrazine-2-carboxamides (Wardell et al., 2008). Yield: 48%; m.p. 473 K, lit. value 471–474 K (Vontor et al., 1989). The colourless plate of (I) used for the
was grown from the slow evaporation of its ethanol solution.The C-bound H atoms were geometrically placed (C—H = 0.95 Å) and refined as riding with Uiso(H) = 1.2Ueq(C). The N-bound H atom was located from a difference map and refined with the distance restraint N—H = 0.88 (1) Å, and with Uiso(H) = 1.2Ueq(N).
Pyrazinamide has well known anti-mycobacterial activity and is the one of the most important drugs used in tuberculosis treatment (Chaisson et al., 2002; Gordin et al., 2000; de Souza, 2006). In continuation of our studies on pyrazinamide derivatives (Wardell et al., 2008; Baddeley et al., 2009; Howie et al., 2010a,b,c,d), we report the structure of N-(4-bromophenyl)pyrazine-2-carboxamide, the title compound, (I).
The molecular structure of (I), Fig. 1, is essentially planar with the dihedral angle formed between the pyrazine and benzene rings being 10.2 (3)°; the r.m.s. deviation of all 16 non-H atoms = 0.103 Å (Spek, 2009). The observed conformation is stabilized by an intramolecular N—H···N hydrogen bond, Table 1.
An analysis of the crystal packing reveals C—H···O, N···Br, Br···π, and π–π interactions. The C—H···O contacts lead to the formation of a supramolecular chain with a flat topology along the a axis. These are sustained in the crystal packing by N···Br halogen bonding [N2···Br1 = 3.207 (5) Å for i: 1 + x, y, 1 + z] (Metrangolo et al., 2008; Pennington et al., 2008), as well as Br···π contacts [C5—Br1···Cg(N2,N3,C8–C11)ii = 3.446 (3) Å, angle at Br1 = 94.59 (18)° for ii: 1 - x, 1 - y, -z]. The resulting double layers stack along the b axis, Fig. 3, with the closest interactions between them being of the form π–π [ring centroid(N2,N3,C8–C11)···ring centroid(C2–C7)iii = 3.803 (4) Å, angle of inclination = 10.2 (3)° for iii: 1 - x, -y, -z].
For the antimycobacterial activity of pyrazinamide, see: Chaisson et al. (2002); Gordin et al. (2000); de Souza (2006). For structural studies of pyrazinamide derivatives; see: Baddeley et al. (2009); Howie et al. (2010a,b,c,d). For the synthesis, see: Wardell et al. (2008); Vontor et al. (1989). For background to halogen bonding, see: Metrangolo et al. (2008); Pennington et al. (2008). For graph-set nomenclature of hydrogen bonds, see: Bernstein et al. (1995). For details of software used to analyse the shape of the molecule, see: Spek (2009). [Please confirm added references]
Data collection: COLLECT (Nonius, 1998); cell
DENZO (Otwinowski & Minor, 1997) and COLLECT (Nonius, 1998); data reduction: DENZO (Otwinowski & Minor, 1997) and COLLECT (Nonius, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).C11H8BrN3O | Z = 2 |
Mr = 278.11 | F(000) = 276 |
Triclinic, P1 | Dx = 1.802 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 5.8396 (4) Å | Cell parameters from 22175 reflections |
b = 7.3317 (7) Å | θ = 2.9–27.5° |
c = 13.3362 (12) Å | µ = 3.99 mm−1 |
α = 101.670 (4)° | T = 120 K |
β = 96.728 (5)° | Plate, colourless |
γ = 110.524 (5)° | 0.18 × 0.10 × 0.02 mm |
V = 512.55 (8) Å3 |
Enraf–Nonius KappaCCD diffractometer | 2110 independent reflections |
Radiation source: Enraf–Nonius FR591 rotating anode | 1792 reflections with I > 2σ(I) |
10 cm confocal mirrors monochromator | Rint = 0.078 |
Detector resolution: 9.091 pixels mm-1 | θmax = 26.5°, θmin = 3.1° |
φ and ω scans | h = −7→7 |
Absorption correction: multi-scan (SADABS; Sheldrick, 2007) | k = −9→9 |
Tmin = 0.764, Tmax = 1.000 | l = −16→16 |
8923 measured reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.054 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.163 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.18 | w = 1/[σ2(Fo2) + (0.1P)2] where P = (Fo2 + 2Fc2)/3 |
2110 reflections | (Δ/σ)max = 0.001 |
148 parameters | Δρmax = 0.55 e Å−3 |
1 restraint | Δρmin = −0.52 e Å−3 |
C11H8BrN3O | γ = 110.524 (5)° |
Mr = 278.11 | V = 512.55 (8) Å3 |
Triclinic, P1 | Z = 2 |
a = 5.8396 (4) Å | Mo Kα radiation |
b = 7.3317 (7) Å | µ = 3.99 mm−1 |
c = 13.3362 (12) Å | T = 120 K |
α = 101.670 (4)° | 0.18 × 0.10 × 0.02 mm |
β = 96.728 (5)° |
Enraf–Nonius KappaCCD diffractometer | 2110 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 2007) | 1792 reflections with I > 2σ(I) |
Tmin = 0.764, Tmax = 1.000 | Rint = 0.078 |
8923 measured reflections |
R[F2 > 2σ(F2)] = 0.054 | 1 restraint |
wR(F2) = 0.163 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.18 | Δρmax = 0.55 e Å−3 |
2110 reflections | Δρmin = −0.52 e Å−3 |
148 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 | ||
Br1 | 0.20472 (10) | 0.24870 (9) | −0.39064 (4) | 0.0227 (2) | |
O1 | 0.8942 (7) | 0.2880 (7) | 0.0884 (3) | 0.0259 (10) | |
N1 | 0.4828 (9) | 0.2414 (8) | 0.0622 (4) | 0.0204 (10) | |
H1N | 0.366 (9) | 0.234 (10) | 0.099 (5) | 0.024* | |
N2 | 0.9106 (9) | 0.2715 (8) | 0.3965 (4) | 0.0223 (11) | |
N3 | 0.4723 (9) | 0.2202 (8) | 0.2621 (4) | 0.0212 (11) | |
C1 | 0.6982 (10) | 0.2603 (8) | 0.1192 (4) | 0.0193 (12) | |
C2 | 0.4304 (10) | 0.2444 (8) | −0.0435 (4) | 0.0170 (11) | |
C3 | 0.1796 (10) | 0.1859 (9) | −0.0902 (5) | 0.0211 (12) | |
H3 | 0.0531 | 0.1461 | −0.0512 | 0.025* | |
C4 | 0.1156 (10) | 0.1861 (9) | −0.1937 (5) | 0.0215 (12) | |
H4 | −0.0549 | 0.1452 | −0.2257 | 0.026* | |
C5 | 0.2979 (11) | 0.2453 (8) | −0.2498 (5) | 0.0192 (12) | |
C6 | 0.5492 (11) | 0.3087 (9) | −0.2035 (5) | 0.0210 (12) | |
H6 | 0.6745 | 0.3519 | −0.2427 | 0.025* | |
C7 | 0.6156 (11) | 0.3088 (9) | −0.1011 (5) | 0.0205 (12) | |
H7 | 0.7868 | 0.3525 | −0.0694 | 0.025* | |
C8 | 0.6915 (11) | 0.2522 (9) | 0.2304 (4) | 0.0203 (12) | |
C9 | 0.9064 (11) | 0.2777 (9) | 0.2980 (5) | 0.0198 (12) | |
H9 | 1.0565 | 0.3004 | 0.2724 | 0.024* | |
C10 | 0.6933 (11) | 0.2377 (10) | 0.4279 (5) | 0.0229 (13) | |
H10 | 0.6870 | 0.2303 | 0.4979 | 0.028* | |
C11 | 0.4790 (11) | 0.2134 (10) | 0.3620 (5) | 0.0243 (13) | |
H11 | 0.3300 | 0.1909 | 0.3883 | 0.029* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br1 | 0.0268 (4) | 0.0286 (4) | 0.0140 (3) | 0.0123 (3) | 0.0025 (2) | 0.0066 (2) |
O1 | 0.021 (2) | 0.040 (3) | 0.019 (2) | 0.0123 (19) | 0.0067 (17) | 0.010 (2) |
N1 | 0.018 (2) | 0.031 (3) | 0.013 (2) | 0.011 (2) | 0.0028 (18) | 0.005 (2) |
N2 | 0.022 (2) | 0.030 (3) | 0.020 (3) | 0.013 (2) | 0.003 (2) | 0.012 (2) |
N3 | 0.018 (2) | 0.024 (3) | 0.017 (3) | 0.005 (2) | 0.0011 (19) | 0.004 (2) |
C1 | 0.020 (3) | 0.015 (3) | 0.019 (3) | 0.005 (2) | 0.003 (2) | 0.002 (2) |
C2 | 0.025 (3) | 0.017 (3) | 0.008 (3) | 0.006 (2) | 0.003 (2) | 0.005 (2) |
C3 | 0.016 (3) | 0.026 (3) | 0.020 (3) | 0.008 (2) | 0.005 (2) | 0.004 (2) |
C4 | 0.019 (3) | 0.027 (3) | 0.019 (3) | 0.011 (2) | 0.002 (2) | 0.004 (2) |
C5 | 0.026 (3) | 0.016 (3) | 0.018 (3) | 0.011 (2) | 0.005 (2) | 0.007 (2) |
C6 | 0.023 (3) | 0.026 (3) | 0.017 (3) | 0.011 (2) | 0.009 (2) | 0.008 (2) |
C7 | 0.018 (3) | 0.023 (3) | 0.021 (3) | 0.007 (2) | 0.000 (2) | 0.010 (2) |
C8 | 0.026 (3) | 0.022 (3) | 0.015 (3) | 0.011 (2) | 0.004 (2) | 0.004 (2) |
C9 | 0.022 (3) | 0.020 (3) | 0.019 (3) | 0.010 (2) | 0.007 (2) | 0.004 (2) |
C10 | 0.029 (3) | 0.034 (3) | 0.013 (3) | 0.014 (3) | 0.012 (2) | 0.013 (2) |
C11 | 0.024 (3) | 0.033 (3) | 0.021 (3) | 0.012 (3) | 0.014 (3) | 0.012 (3) |
Br1—C5 | 1.901 (6) | C3—H3 | 0.9500 |
O1—C1 | 1.226 (6) | C4—C5 | 1.369 (8) |
N1—C1 | 1.337 (7) | C4—H4 | 0.9500 |
N1—C2 | 1.413 (7) | C5—C6 | 1.394 (8) |
N1—H1N | 0.88 (6) | C6—C7 | 1.375 (8) |
N2—C9 | 1.321 (8) | C6—H6 | 0.9500 |
N2—C10 | 1.339 (8) | C7—H7 | 0.9500 |
N3—C11 | 1.340 (8) | C8—C9 | 1.387 (8) |
N3—C8 | 1.352 (8) | C9—H9 | 0.9500 |
C1—C8 | 1.501 (8) | C10—C11 | 1.376 (8) |
C2—C3 | 1.398 (8) | C10—H10 | 0.9500 |
C2—C7 | 1.402 (8) | C11—H11 | 0.9500 |
C3—C4 | 1.387 (8) | ||
C1—N1—C2 | 128.5 (5) | C6—C5—Br1 | 120.2 (4) |
C1—N1—H1N | 113 (5) | C7—C6—C5 | 120.0 (5) |
C2—N1—H1N | 119 (5) | C7—C6—H6 | 120.0 |
C9—N2—C10 | 116.0 (5) | C5—C6—H6 | 120.0 |
C11—N3—C8 | 115.2 (5) | C6—C7—C2 | 120.0 (5) |
O1—C1—N1 | 125.4 (6) | C6—C7—H7 | 120.0 |
O1—C1—C8 | 119.5 (5) | C2—C7—H7 | 120.0 |
N1—C1—C8 | 115.1 (5) | N3—C8—C9 | 121.6 (5) |
C3—C2—C7 | 119.4 (5) | N3—C8—C1 | 118.2 (5) |
C3—C2—N1 | 117.1 (5) | C9—C8—C1 | 120.2 (5) |
C7—C2—N1 | 123.5 (5) | N2—C9—C8 | 122.6 (5) |
C4—C3—C2 | 120.0 (5) | N2—C9—H9 | 118.7 |
C4—C3—H3 | 120.0 | C8—C9—H9 | 118.7 |
C2—C3—H3 | 120.0 | N2—C10—C11 | 122.1 (5) |
C5—C4—C3 | 120.1 (5) | N2—C10—H10 | 119.0 |
C5—C4—H4 | 120.0 | C11—C10—H10 | 119.0 |
C3—C4—H4 | 120.0 | N3—C11—C10 | 122.6 (5) |
C4—C5—C6 | 120.6 (6) | N3—C11—H11 | 118.7 |
C4—C5—Br1 | 119.1 (4) | C10—C11—H11 | 118.7 |
C2—N1—C1—O1 | 1.4 (10) | N1—C2—C7—C6 | −179.5 (6) |
C2—N1—C1—C8 | 179.5 (5) | C11—N3—C8—C9 | −0.6 (8) |
C1—N1—C2—C3 | 169.0 (5) | C11—N3—C8—C1 | 179.6 (5) |
C1—N1—C2—C7 | −13.3 (9) | O1—C1—C8—N3 | −179.6 (5) |
C7—C2—C3—C4 | 2.0 (9) | N1—C1—C8—N3 | 2.2 (8) |
N1—C2—C3—C4 | 179.8 (5) | O1—C1—C8—C9 | 0.6 (8) |
C2—C3—C4—C5 | −0.6 (9) | N1—C1—C8—C9 | −177.6 (5) |
C3—C4—C5—C6 | −1.0 (9) | C10—N2—C9—C8 | 0.4 (9) |
C3—C4—C5—Br1 | −178.8 (4) | N3—C8—C9—N2 | 0.3 (9) |
C4—C5—C6—C7 | 1.2 (9) | C1—C8—C9—N2 | −179.9 (5) |
Br1—C5—C6—C7 | 179.0 (4) | C9—N2—C10—C11 | −0.8 (9) |
C5—C6—C7—C2 | 0.2 (9) | C8—N3—C11—C10 | 0.2 (9) |
C3—C2—C7—C6 | −1.8 (9) | N2—C10—C11—N3 | 0.5 (10) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N···N3 | 0.88 (6) | 2.22 (6) | 2.708 (7) | 115 (5) |
C3—H3···O1i | 0.95 | 2.39 | 3.177 (8) | 140 |
Symmetry code: (i) x−1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C11H8BrN3O |
Mr | 278.11 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 120 |
a, b, c (Å) | 5.8396 (4), 7.3317 (7), 13.3362 (12) |
α, β, γ (°) | 101.670 (4), 96.728 (5), 110.524 (5) |
V (Å3) | 512.55 (8) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 3.99 |
Crystal size (mm) | 0.18 × 0.10 × 0.02 |
Data collection | |
Diffractometer | Enraf–Nonius KappaCCD |
Absorption correction | Multi-scan (SADABS; Sheldrick, 2007) |
Tmin, Tmax | 0.764, 1.000 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8923, 2110, 1792 |
Rint | 0.078 |
(sin θ/λ)max (Å−1) | 0.628 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.054, 0.163, 1.18 |
No. of reflections | 2110 |
No. of parameters | 148 |
No. of restraints | 1 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.55, −0.52 |
Computer programs: DENZO (Otwinowski & Minor, 1997) and COLLECT (Nonius, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006), publCIF (Westrip, 2010).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N···N3 | 0.88 (6) | 2.22 (6) | 2.708 (7) | 115 (5) |
C3—H3···O1i | 0.95 | 2.39 | 3.177 (8) | 140 |
Symmetry code: (i) x−1, y, z. |
Footnotes
‡Additional correspondence author, e-mail: j.wardell@abdn.ac.uk.
Acknowledgements
The use of the EPSRC X-ray Crystallographic Service at the University of Southampton, England, and the valuable assistance of the staff there are gratefully acknowledged. JLW acknowledges support from CAPES (Brazil).
References
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Pyrazinamide has well known anti-mycobacterial activity and is the one of the most important drugs used in tuberculosis treatment (Chaisson et al., 2002; Gordin et al., 2000; de Souza, 2006). In continuation of our studies on pyrazinamide derivatives (Wardell et al., 2008; Baddeley et al., 2009; Howie et al., 2010a,b,c,d), we report the structure of N-(4-bromophenyl)pyrazine-2-carboxamide, the title compound, (I).
The molecular structure of (I), Fig. 1, is essentially planar with the dihedral angle formed between the pyrazine and benzene rings being 10.2 (3)°; the r.m.s. deviation of all 16 non-H atoms = 0.103 Å (Spek, 2009). The observed conformation is stabilized by an intramolecular N—H···N hydrogen bond, Table 1.
An analysis of the crystal packing reveals C—H···O, N···Br, Br···π, and π–π interactions. The C—H···O contacts lead to the formation of a supramolecular chain with a flat topology along the a axis. These are sustained in the crystal packing by N···Br halogen bonding [N2···Br1 = 3.207 (5) Å for i: 1 + x, y, 1 + z] (Metrangolo et al., 2008; Pennington et al., 2008), as well as Br···π contacts [C5—Br1···Cg(N2,N3,C8–C11)ii = 3.446 (3) Å, angle at Br1 = 94.59 (18)° for ii: 1 - x, 1 - y, -z]. The resulting double layers stack along the b axis, Fig. 3, with the closest interactions between them being of the form π–π [ring centroid(N2,N3,C8–C11)···ring centroid(C2–C7)iii = 3.803 (4) Å, angle of inclination = 10.2 (3)° for iii: 1 - x, -y, -z].