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ISSN: 2056-9890

5-Bromo-2-hy­dr­oxy­benzo­nitrile

aDepartment of Chemistry, Vassar College, Poughkeepsie, NY 12604, USA
*Correspondence e-mail: jotanski@vassar.edu

(Received 5 July 2012; accepted 11 July 2012; online 1 August 2012)

The title compound, C7H4BrNO, crystallizes with two mol­ecules in the asymmetric unit. The two molecules exhibit nearly linear C—C≡N nitrile bond angles of 179.1 (4) and 177.1 (4)°. In the crystal, the mol­ecules are linked into a one-dimensional hydrogen-bonded chain by inter­actions between the phenol H atom and the nitrile N atom [N⋯O = 2.805 (4) and 2.810 (4) Å].

Related literature

For information on the synthesis of the title compound, see: Anwar & Hansen (2008[Anwar, H. F. & Hansen, T. V. (2008). Tetrahedron Lett. 49, 4443-4445.]); Bonnichon et al. (1999[Bonnichon, F., Grabner, G., Guyot, G. & Richard, C. (1999). J. Chem. Soc. Perkin Trans. 2, pp. 1203-1210.]); Oberhauser (1997[Oberhauser, T. (1997). J. Org. Chem. 62, 4504-4506.]); Tamilselvan et al. (2009[Tamilselvan, P., Basavaraju, Y. B., Sampathkumar, E. & Murugesan, R. (2009). Catal. Commun. 10, 716-719.]). For use as a synthetic reagent, see: Jiang et al. (2011[Jiang, S., Tala, S. R., Lu, H., Abo-Dya, N. E., Avan, I., Gyanda, K., Lu, L., Katritzky, A. R. & Debnath, A. K. (2011). J. Med. Chem. 54, 572-579.]); Tsuhako et al. (2012[Tsuhako, A. L., et al. (2012). Bioorg. Med. Chem. Lett. 22, 3732-3738.]); Wetzel et al. (2011[Wetzel, M., Marchais-Oberwinkler, S., Perspicace, E., Möller, G., Adamski, J. & Hartmann, R. W. (2011). J. Med. Chem. 54, 7547-7557.]). For a related crystal structure, see: Beswick et al. (1996[Beswick, C., Kubicki, M. & Codding, P. W. (1996). Acta Cryst. C52, 3171-3173.]).

[Scheme 1]

Experimental

Crystal data
  • C7H4BrNO

  • Mr = 198.01

  • Triclinic, [P \overline 1]

  • a = 3.8422 (3) Å

  • b = 8.5166 (7) Å

  • c = 21.6507 (18) Å

  • α = 97.074 (1)°

  • β = 91.991 (1)°

  • γ = 97.068 (1)°

  • V = 696.83 (10) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 5.82 mm−1

  • T = 125 K

  • 0.20 × 0.07 × 0.03 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2007[Bruker (2007). SAINT, SADABS and APEX2. Bruxer AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.389, Tmax = 0.845

  • 11040 measured reflections

  • 4213 independent reflections

  • 3254 reflections with I > 2σ(I)

  • Rint = 0.032

Refinement
  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.100

  • S = 1.03

  • 4213 reflections

  • 187 parameters

  • 2 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 1.67 e Å−3

  • Δρmin = −0.57 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1⋯N2 0.83 (2) 1.98 (2) 2.805 (4) 170 (5)
O2—H2⋯N1i 0.84 (2) 1.98 (2) 2.810 (4) 175 (5)
Symmetry code: (i) x-1, y+1, z.

Data collection: APEX2 (Bruker, 2007[Bruker (2007). SAINT, SADABS and APEX2. Bruxer AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). SAINT, SADABS and APEX2. Bruxer AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

The title compound, 5-bromo-2-hydroxybenzonitrile, may be prepared by a variety of methods, including bromination of o-cyanophenol (Oberhauser, 1997), additon of nitrile to p-bromophenol (Anwar & Hansen, 2008), cobalt(II) catalyzed conversion of 5-bromo-2-hydroxyaldoxime to the nitrile (Tamilselvan et al., 2009), and photochemically from 5-chloro-2-hydroxybenzonitrile in the presence of bromide ions (Bonnichon et al., 1999). The 5-bromo-2-hydroxybenzonitrile is used as a synthetic reagent in the synthesis of biologically active compounds such as potential antiretroviral drugs (Jiang et al., 2011), cancer therapies (Tsuhako et al., 2012), and osteoporosis treatments (Wetzel et al., 2011).

The asymmetric unit contains two uniqe molecules of the title compound (Fig. 1) which are hydrogen bonded into an infinite one-dimensional chain (Fig. 2). The phenoxy group acts as the hydrogen donor and the nitrile group as the acceptor, with O···N distances of 2.805 (4)Å and 2.810 (4)Å, and O–H···N angles of 170 (5)° and 175 (5)°. The metrical parameters are similar to those found in the structure of o-cyanonitrile, which also crystallizes with two molecules in the asymmetric unit, and exhibts O···N distances of 2.795 (2)Å and 2.798 (2)Å, and O–H···N angles of 173 (2)° and 172 (2)° (Beswick et al., 1996). As in the structure of o-cyanonitrile, the molecules of the title compound are nearly planar, with a root mean square deviations from the plane of all atoms, excluding the aryl H atoms, of 0.0334Å and 0.2747Å. In each molecule in the asymmetric unit, the greatest deviation from the plane is the phenolic hydrogen atom, presumably to maximize the hydrogen bonding interaction between neighboring molecules, which make a dihedral angle between them of 12.6 (5)°.

Related literature top

For information on the synthesis of the title compound, see: Anwar & Hansen (2008); Bonnichon et al. (1999); Oberhauser (1997); Tamilselvan et al. (2009). For use as a synthetic reagent, see: Jiang et al. (2011); Tsuhako et al. (2012); Wetzel et al. (2011). For a related crystal structure, see: Beswick et al. (1996).

Experimental top

Crystalline 5-bromo-2-hydroxybenzonitrile was purchased from Aldrich Chemical Company, USA, and was recrystallized from chloroform.

Refinement top

Hydrogen atoms based on carbon were included in calculated positions and refined using a riding model at C–H = 0.95Å and Uiso(H) = 1.2Ueq(Caryl). Hydrogen atoms based on oxygen were refined semifreely with the help of a distance restraint O–H = 0.84Å, and Uiso(H) = 1.5Ueq(O).

Structure description top

The title compound, 5-bromo-2-hydroxybenzonitrile, may be prepared by a variety of methods, including bromination of o-cyanophenol (Oberhauser, 1997), additon of nitrile to p-bromophenol (Anwar & Hansen, 2008), cobalt(II) catalyzed conversion of 5-bromo-2-hydroxyaldoxime to the nitrile (Tamilselvan et al., 2009), and photochemically from 5-chloro-2-hydroxybenzonitrile in the presence of bromide ions (Bonnichon et al., 1999). The 5-bromo-2-hydroxybenzonitrile is used as a synthetic reagent in the synthesis of biologically active compounds such as potential antiretroviral drugs (Jiang et al., 2011), cancer therapies (Tsuhako et al., 2012), and osteoporosis treatments (Wetzel et al., 2011).

The asymmetric unit contains two uniqe molecules of the title compound (Fig. 1) which are hydrogen bonded into an infinite one-dimensional chain (Fig. 2). The phenoxy group acts as the hydrogen donor and the nitrile group as the acceptor, with O···N distances of 2.805 (4)Å and 2.810 (4)Å, and O–H···N angles of 170 (5)° and 175 (5)°. The metrical parameters are similar to those found in the structure of o-cyanonitrile, which also crystallizes with two molecules in the asymmetric unit, and exhibts O···N distances of 2.795 (2)Å and 2.798 (2)Å, and O–H···N angles of 173 (2)° and 172 (2)° (Beswick et al., 1996). As in the structure of o-cyanonitrile, the molecules of the title compound are nearly planar, with a root mean square deviations from the plane of all atoms, excluding the aryl H atoms, of 0.0334Å and 0.2747Å. In each molecule in the asymmetric unit, the greatest deviation from the plane is the phenolic hydrogen atom, presumably to maximize the hydrogen bonding interaction between neighboring molecules, which make a dihedral angle between them of 12.6 (5)°.

For information on the synthesis of the title compound, see: Anwar & Hansen (2008); Bonnichon et al. (1999); Oberhauser (1997); Tamilselvan et al. (2009). For use as a synthetic reagent, see: Jiang et al. (2011); Tsuhako et al. (2012); Wetzel et al. (2011). For a related crystal structure, see: Beswick et al. (1996).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A view of the two independent molecules of the title compound with the atom numbering scheme. Displacement ellipsoids are shown at the 50% probability level. H atoms are presented as a small spheres of arbitrary radius. One of the hydrogen bonds is drawn with a dashed line.
[Figure 2] Fig. 2. A view of the one-dimensional hydrogen bonding chain. H atoms not involved in H-bonds are omitted for clarity.
5-Bromo-2-hydroxybenzonitrile top
Crystal data top
C7H4BrNOZ = 4
Mr = 198.01F(000) = 384
Triclinic, P1Dx = 1.888 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 3.8422 (3) ÅCell parameters from 5206 reflections
b = 8.5166 (7) Åθ = 2.5–30.5°
c = 21.6507 (18) ŵ = 5.82 mm1
α = 97.074 (1)°T = 125 K
β = 91.991 (1)°Needle, colourless
γ = 97.068 (1)°0.20 × 0.07 × 0.03 mm
V = 696.83 (10) Å3
Data collection top
Bruker APEXII CCD
diffractometer
4213 independent reflections
Radiation source: fine-focus sealed tube3254 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.032
φ and ω scansθmax = 30.5°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
h = 55
Tmin = 0.389, Tmax = 0.845k = 1212
11040 measured reflectionsl = 3030
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.100H atoms treated by a mixture of independent and constrained refinement
S = 1.03 w = 1/[σ2(Fo2) + (0.050P)2 + 0.6935P]
where P = (Fo2 + 2Fc2)/3
4213 reflections(Δ/σ)max = 0.001
187 parametersΔρmax = 1.67 e Å3
2 restraintsΔρmin = 0.57 e Å3
Crystal data top
C7H4BrNOγ = 97.068 (1)°
Mr = 198.01V = 696.83 (10) Å3
Triclinic, P1Z = 4
a = 3.8422 (3) ÅMo Kα radiation
b = 8.5166 (7) ŵ = 5.82 mm1
c = 21.6507 (18) ÅT = 125 K
α = 97.074 (1)°0.20 × 0.07 × 0.03 mm
β = 91.991 (1)°
Data collection top
Bruker APEXII CCD
diffractometer
4213 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
3254 reflections with I > 2σ(I)
Tmin = 0.389, Tmax = 0.845Rint = 0.032
11040 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0432 restraints
wR(F2) = 0.100H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 1.67 e Å3
4213 reflectionsΔρmin = 0.57 e Å3
187 parameters
Special details top

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 > 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) top
xyzUiso*/Ueq
Br10.18318 (9)0.28671 (4)0.512507 (15)0.02561 (10)
Br20.29449 (9)0.79771 (4)0.004330 (16)0.02483 (10)
O10.5299 (7)0.0480 (3)0.25051 (11)0.0272 (5)
H10.477 (12)0.107 (5)0.2245 (17)0.041*
O20.0783 (7)0.5153 (3)0.23932 (11)0.0256 (5)
H20.155 (11)0.581 (4)0.2658 (16)0.038*
N10.6255 (9)0.2737 (4)0.32638 (14)0.0297 (7)
N20.2873 (9)0.2144 (4)0.15707 (14)0.0284 (7)
C10.5484 (9)0.1490 (4)0.33933 (15)0.0219 (6)
C20.4527 (8)0.0091 (4)0.35481 (15)0.0198 (6)
C30.4427 (9)0.1083 (4)0.30815 (15)0.0205 (6)
C40.3500 (9)0.2610 (4)0.32282 (16)0.0243 (7)
H4A0.33930.32890.29130.029*
C50.2735 (9)0.3141 (4)0.38330 (16)0.0224 (6)
H5A0.21140.41850.39330.027*
C60.2875 (8)0.2141 (4)0.42964 (15)0.0200 (6)
C70.3737 (8)0.0620 (4)0.41583 (14)0.0192 (6)
H7A0.37930.00610.44730.023*
C80.2157 (9)0.3355 (4)0.14778 (15)0.0213 (6)
C90.1384 (8)0.4920 (4)0.13853 (15)0.0188 (6)
C100.0049 (8)0.5841 (4)0.18745 (15)0.0196 (6)
C110.0606 (9)0.7398 (4)0.17991 (15)0.0211 (6)
H11A0.15680.80380.21240.025*
C120.0238 (9)0.8011 (4)0.12526 (16)0.0218 (6)
H12A0.01290.90730.12050.026*
C130.1624 (8)0.7076 (4)0.07722 (15)0.0190 (6)
C140.2219 (8)0.5542 (4)0.08324 (15)0.0196 (6)
H14A0.31820.49130.05040.023*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.02688 (19)0.02853 (19)0.02188 (17)0.00764 (14)0.00549 (13)0.00014 (13)
Br20.02437 (18)0.02336 (17)0.02838 (18)0.00123 (13)0.00333 (13)0.01102 (13)
O10.0410 (15)0.0240 (13)0.0186 (11)0.0098 (11)0.0007 (10)0.0047 (9)
O20.0380 (14)0.0226 (12)0.0173 (11)0.0072 (11)0.0050 (10)0.0026 (9)
N10.0419 (19)0.0259 (16)0.0231 (15)0.0104 (13)0.0048 (13)0.0035 (12)
N20.0417 (18)0.0210 (15)0.0223 (14)0.0063 (13)0.0009 (13)0.0004 (11)
C10.0268 (17)0.0235 (17)0.0159 (14)0.0034 (13)0.0015 (12)0.0046 (12)
C20.0197 (15)0.0184 (15)0.0215 (15)0.0034 (12)0.0004 (12)0.0024 (12)
C30.0193 (15)0.0231 (16)0.0184 (15)0.0016 (12)0.0005 (12)0.0018 (12)
C40.0289 (18)0.0220 (16)0.0230 (16)0.0050 (13)0.0003 (13)0.0058 (13)
C50.0246 (16)0.0196 (15)0.0235 (16)0.0057 (12)0.0008 (13)0.0025 (12)
C60.0177 (15)0.0242 (16)0.0182 (15)0.0036 (12)0.0014 (12)0.0023 (12)
C70.0204 (15)0.0205 (15)0.0170 (14)0.0028 (12)0.0005 (12)0.0040 (12)
C80.0268 (16)0.0213 (16)0.0154 (14)0.0021 (13)0.0010 (12)0.0017 (12)
C90.0207 (15)0.0170 (14)0.0185 (14)0.0031 (12)0.0004 (12)0.0016 (11)
C100.0199 (15)0.0179 (15)0.0198 (15)0.0002 (11)0.0021 (12)0.0009 (12)
C110.0235 (16)0.0183 (15)0.0201 (15)0.0026 (12)0.0008 (12)0.0021 (12)
C120.0218 (16)0.0170 (15)0.0260 (16)0.0023 (12)0.0043 (13)0.0025 (12)
C130.0175 (14)0.0184 (15)0.0209 (15)0.0009 (11)0.0002 (12)0.0051 (12)
C140.0167 (14)0.0196 (15)0.0214 (15)0.0005 (11)0.0003 (12)0.0004 (12)
Geometric parameters (Å, º) top
Br1—C61.897 (3)C5—C61.397 (4)
Br2—C131.896 (3)C5—H5A0.9500
O1—C31.359 (4)C6—C71.376 (4)
O1—H10.834 (19)C7—H7A0.9500
O2—C101.352 (4)C8—C91.436 (4)
O2—H20.836 (19)C9—C141.399 (4)
N1—C11.142 (4)C9—C101.408 (4)
N2—C81.139 (4)C10—C111.396 (4)
C1—C21.442 (4)C11—C121.384 (5)
C2—C31.397 (4)C11—H11A0.9500
C2—C71.398 (4)C12—C131.392 (5)
C3—C41.393 (5)C12—H12A0.9500
C4—C51.385 (5)C13—C141.375 (4)
C4—H4A0.9500C14—H14A0.9500
C3—O1—H1110 (3)C2—C7—H7A120.4
C10—O2—H2110 (3)N2—C8—C9177.1 (4)
N1—C1—C2179.1 (4)C14—C9—C10120.9 (3)
C3—C2—C7120.8 (3)C14—C9—C8120.4 (3)
C3—C2—C1119.0 (3)C10—C9—C8118.6 (3)
C7—C2—C1120.2 (3)O2—C10—C11124.1 (3)
O1—C3—C4124.0 (3)O2—C10—C9117.3 (3)
O1—C3—C2116.7 (3)C11—C10—C9118.7 (3)
C4—C3—C2119.3 (3)C12—C11—C10120.2 (3)
C5—C4—C3120.1 (3)C12—C11—H11A119.9
C5—C4—H4A119.9C10—C11—H11A119.9
C3—C4—H4A119.9C11—C12—C13120.2 (3)
C4—C5—C6120.0 (3)C11—C12—H12A119.9
C4—C5—H5A120.0C13—C12—H12A119.9
C6—C5—H5A120.0C14—C13—C12121.0 (3)
C7—C6—C5120.7 (3)C14—C13—Br2119.6 (2)
C7—C6—Br1119.2 (2)C12—C13—Br2119.3 (2)
C5—C6—Br1120.1 (2)C13—C14—C9118.9 (3)
C6—C7—C2119.1 (3)C13—C14—H14A120.5
C6—C7—H7A120.4C9—C14—H14A120.5
C7—C2—C3—O1178.8 (3)C14—C9—C10—O2180.0 (3)
C1—C2—C3—O10.8 (5)C8—C9—C10—O23.4 (4)
C7—C2—C3—C40.5 (5)C14—C9—C10—C110.4 (5)
C1—C2—C3—C4179.9 (3)C8—C9—C10—C11176.2 (3)
O1—C3—C4—C5178.4 (3)O2—C10—C11—C12179.7 (3)
C2—C3—C4—C50.9 (5)C9—C10—C11—C120.1 (5)
C3—C4—C5—C60.3 (5)C10—C11—C12—C130.5 (5)
C4—C5—C6—C70.6 (5)C11—C12—C13—C140.8 (5)
C4—C5—C6—Br1179.9 (3)C11—C12—C13—Br2177.3 (2)
C5—C6—C7—C21.0 (5)C12—C13—C14—C90.5 (5)
Br1—C6—C7—C2179.6 (2)Br2—C13—C14—C9177.0 (2)
C3—C2—C7—C60.4 (5)C10—C9—C14—C130.1 (5)
C1—C2—C7—C6179.2 (3)C8—C9—C14—C13176.4 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N20.83 (2)1.98 (2)2.805 (4)170 (5)
O2—H2···N1i0.84 (2)1.98 (2)2.810 (4)175 (5)
Symmetry code: (i) x1, y+1, z.

Experimental details

Crystal data
Chemical formulaC7H4BrNO
Mr198.01
Crystal system, space groupTriclinic, P1
Temperature (K)125
a, b, c (Å)3.8422 (3), 8.5166 (7), 21.6507 (18)
α, β, γ (°)97.074 (1), 91.991 (1), 97.068 (1)
V3)696.83 (10)
Z4
Radiation typeMo Kα
µ (mm1)5.82
Crystal size (mm)0.20 × 0.07 × 0.03
Data collection
DiffractometerBruker APEXII CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2007)
Tmin, Tmax0.389, 0.845
No. of measured, independent and
observed [I > 2σ(I)] reflections
11040, 4213, 3254
Rint0.032
(sin θ/λ)max1)0.714
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.100, 1.03
No. of reflections4213
No. of parameters187
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)1.67, 0.57

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N20.834 (19)1.98 (2)2.805 (4)170 (5)
O2—H2···N1i0.836 (19)1.98 (2)2.810 (4)175 (5)
Symmetry code: (i) x1, y+1, z.
 

Acknowledgements

This work was supported by Vassar College. X-ray facilities were provided by the US National Science Foundation (grant No. 0521237 to JMT).

References

First citationAnwar, H. F. & Hansen, T. V. (2008). Tetrahedron Lett. 49, 4443–4445.  Web of Science CrossRef CAS
First citationBeswick, C., Kubicki, M. & Codding, P. W. (1996). Acta Cryst. C52, 3171–3173.  CSD CrossRef CAS Web of Science IUCr Journals
First citationBonnichon, F., Grabner, G., Guyot, G. & Richard, C. (1999). J. Chem. Soc. Perkin Trans. 2, pp. 1203–1210.  CrossRef
First citationBruker (2007). SAINT, SADABS and APEX2. Bruxer AXS Inc., Madison, Wisconsin, USA.
First citationJiang, S., Tala, S. R., Lu, H., Abo-Dya, N. E., Avan, I., Gyanda, K., Lu, L., Katritzky, A. R. & Debnath, A. K. (2011). J. Med. Chem. 54, 572–579.  Web of Science CrossRef CAS PubMed
First citationOberhauser, T. (1997). J. Org. Chem. 62, 4504–4506.  CrossRef PubMed CAS Web of Science
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals
First citationTamilselvan, P., Basavaraju, Y. B., Sampathkumar, E. & Murugesan, R. (2009). Catal. Commun. 10, 716–719.  Web of Science CrossRef CAS
First citationTsuhako, A. L., et al. (2012). Bioorg. Med. Chem. Lett. 22, 3732–3738.  Web of Science CrossRef CAS PubMed
First citationWetzel, M., Marchais-Oberwinkler, S., Perspicace, E., Möller, G., Adamski, J. & Hartmann, R. W. (2011). J. Med. Chem. 54, 7547–7557.  Web of Science CrossRef CAS PubMed

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