organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

(E)-1-Methyl-5-(3-methyl-4-chloro­phen­­oxy)-3-tri­fluoro­meth­yl-1H-pyrazole-4-carbaldehyde O-acetyl­oxime

aCollege of Chemistry and Chemical Engineering, Nantong University, Nantong 226019, People's Republic of China
*Correspondence e-mail: gaofz2005@yahoo.com.cn

(Received 16 February 2011; accepted 22 February 2011; online 26 February 2011)

In the title mol­ecule, C15H13ClF3N3O3, the pyrazole and benzene rings form a dihedral angle of 77.6 (3)°. In the crystal, mol­ecules related by translation along the a axis are linked into chains via C—H⋯O hydrogen bonds. The crystal packing is stabilized further by weak ππ [centroid–centroid distance = 3.734 (6) Å] and dipole–dipole inter­actions [C⋯O = 3.174 (2) Å].

Related literature

For the bioactivity of pyrazole derivatives, see: Hagiwara & Suzuki (1996[Hagiwara, K. & Suzuki, H. (1996). Jpn Patent No. 08193067.]); Ranatunge et al. (2004[Ranatunge, R. R., Augustyniak, M., Bandarage, U. K., Earl, R. A., Ellis, J. L., Garvey, D. S., Janero, D. R., Letts, L. G., Martino, A. M., Murty, M. G., Richardson, S. K., Schroeder, J. D., Shumway, M. J., Tam, S. W., Trocha, A. M. & Young, D. V. (2004). J. Med. Chem. 47, 2180-2193.]). For related structures, see: Fu et al. (2008[Fu, N., Zou, X.-M., Lin, D.-Y., Zhu, Y.-Q. & Yang, H.-Z. (2008). Acta Cryst. E64, o192.]); Li et al. (2006[Li, Y., Yang, X.-P., Zhang, H.-Q., Meng, X.-G. & Liu, Z.-J. (2006). Acta Cryst. E62, o2027-o2029.]). For the biological activity of compounds containing an oxime ester fragment, see: Vonhoff et al. (1999[Vonhoff, S., Piens, K., Pipelier, M., Braet, C., Claeyssens, M. & Vasella, A. (1999). Helv. Chim. Acta, 82, 963-980.]); Wood et al. (1997[Wood, J. L., Stoltz, B. M., Goodman, S. N. & Onwueme, K. (1997). J. Am. Chem. Soc. 119, 9652-9661.]).

[Scheme 1]

Experimental

Crystal data
  • C15H13ClF3N3O3

  • Mr = 375.73

  • Orthorhombic, P b c n

  • a = 11.951 (2) Å

  • b = 19.549 (4) Å

  • c = 13.726 (3) Å

  • V = 3206.8 (11) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.29 mm−1

  • T = 113 K

  • 0.16 × 0.12 × 0.08 mm

Data collection
  • Rigaku Saturn diffractometer

  • Absorption correction: multi-scan (CrystalClear; Rigaku, 2008[Rigaku (2008). CrystalClear. Rigaku Corporation, Toyko, Japan.]) Tmin = 0.955, Tmax = 0.977

  • 21575 measured reflections

  • 3686 independent reflections

  • 3208 reflections with I > 2σ(I)

  • Rint = 0.061

Refinement
  • R[F2 > 2σ(F2)] = 0.046

  • wR(F2) = 0.115

  • S = 1.10

  • 3686 reflections

  • 229 parameters

  • H-atom parameters constrained

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.33 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C5—H5B⋯O3i 0.96 2.55 3.102 (2) 117
Symmetry code: (i) x+1, y, z.

Data collection: CrystalClear (Rigaku, 2008[Rigaku (2008). CrystalClear. Rigaku Corporation, Toyko, Japan.]); cell refinement: CrystalClear; data reduction: CrystalClear; 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

Pyrazole derivatives have been paid much attention due to their diverse biological activities. Some of them are used as fungicide, insecticide, and antitumor agents (Hagiwara & Suzuki, 1996; Ranatunge et al., 2004). Several studies have recently reported the crystal structures of related pyrazole compounds (Li et al., 2006; Fu et al., 2008). On the other hand, oxime ester group as an efficient pharmacophore was widely used in the field of agricultural and medicinal chemistry (Wood et al. , 1997; Vonhoff et al., 1999). Motivated by the above observations and in continuation of research on the bioactivities of pyrazole derivatives, we synthesized the title compound (I).

In (I) (Fig. 1), the dihedral angle between the planes of the phenyl ring and the pyrazoe ring is 77.6 (3)°. In the crystal structure, the molecules related by translation along axis a are linked into chains via C—H···O hydrogen bonds (Table 2; Fig. 2). The crystal packing is stabilized further by the weak ππ and dipole-dipole interactions (Table 1).

Related literature top

For the bioactivity of pyrazole derivatives, see: Hagiwara & Suzuki (1996); Ranatunge et al. (2004). For related structures, see: Fu et al. (2008); Li et al. (2006). For the biological activity of compounds containing an oxime ester fragment, see: Vonhoff et al. (1999); Wood et al. (1997).

Experimental top

To a stirred solution of 1-methyl-3-(trifluoromethyl)-5-phenoxy-1H- pyrazole-4-carbaldehyde oxime (8 mmol),and sodium bicarbonate (20 mmol) in 80 ml of chloroform, was added dropwise acetyl chloride(10 mmol) at room temperature. The reaction mixture was heated to reflux for 8 h. After cooling to room temperature, the mixture was washed with water (3 * 10 ml) and then with saturated brine (3 * 20 ml), and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure, and the residue was recrystallized from petroleum ether/ethyl acetate (8:1 v/v) to obtain colourless crystals.

Refinement top

All H atoms were placed in calculated positions, with C–H = 0.93 - 0.96 Å, and included in the final cycles of refinement using a riding model, with Uiso(H) = 1.2-1.5 Ueq(C).

Computing details top

Data collection: CrystalClear (Rigaku, 2008); cell refinement: CrystalClear (Rigaku, 2008); data reduction: CrystalClear (Rigaku, 2008); 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. The molecular structure of (I) showing the atomic numbering and displacement ellipsoids drawn at the 30% probability level.
[Figure 2] Fig. 2. A portion of the crystal packing of (I). Hydrogen bonds drawn as dashed lines.
(E)-1-Methyl-5-(3-methyl-4-chlorophenoxy)-3-trifluoromethyl- 1H-pyrazole-4-carbaldehyde O-acetyloxime top
Crystal data top
C15H13ClF3N3O3F(000) = 1536
Mr = 375.73Dx = 1.557 Mg m3
Orthorhombic, PbcnMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2n 2abCell parameters from 7040 reflections
a = 11.951 (2) Åθ = 2.0–27.5°
b = 19.549 (4) ŵ = 0.29 mm1
c = 13.726 (3) ÅT = 113 K
V = 3206.8 (11) Å3Orthorhombic, colourless
Z = 80.16 × 0.12 × 0.08 mm
Data collection top
Rigaku Saturn
diffractometer
3686 independent reflections
Radiation source: rotating anode3208 reflections with I > 2σ(I)
Confocal monochromatorRint = 0.061
ω scansθmax = 27.5°, θmin = 2.0°
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2008)
h = 1215
Tmin = 0.955, Tmax = 0.977k = 2524
21575 measured reflectionsl = 1417
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)] = 0.046Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.115H-atom parameters constrained
S = 1.10 w = 1/[σ2(Fo2) + (0.0516P)2 + 1.0705P]
where P = (Fo2 + 2Fc2)/3
3686 reflections(Δ/σ)max = 0.005
229 parametersΔρmax = 0.29 e Å3
0 restraintsΔρmin = 0.33 e Å3
Crystal data top
C15H13ClF3N3O3V = 3206.8 (11) Å3
Mr = 375.73Z = 8
Orthorhombic, PbcnMo Kα radiation
a = 11.951 (2) ŵ = 0.29 mm1
b = 19.549 (4) ÅT = 113 K
c = 13.726 (3) Å0.16 × 0.12 × 0.08 mm
Data collection top
Rigaku Saturn
diffractometer
3686 independent reflections
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2008)
3208 reflections with I > 2σ(I)
Tmin = 0.955, Tmax = 0.977Rint = 0.061
21575 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0460 restraints
wR(F2) = 0.115H-atom parameters constrained
S = 1.10Δρmax = 0.29 e Å3
3686 reflectionsΔρmin = 0.33 e Å3
229 parameters
Special details top

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) top
xyzUiso*/Ueq
Cl10.78669 (4)1.02584 (3)1.15028 (4)0.03467 (15)
F11.04265 (9)0.54780 (6)0.90733 (11)0.0422 (3)
F20.89699 (11)0.56763 (6)0.82078 (10)0.0429 (3)
F30.88936 (10)0.57911 (6)0.97538 (10)0.0415 (3)
O10.97587 (11)0.84054 (6)0.85735 (9)0.0258 (3)
O20.62455 (10)0.75817 (7)0.87263 (9)0.0254 (3)
O30.45722 (10)0.80203 (7)0.86552 (10)0.0311 (3)
N11.09611 (12)0.67936 (8)0.88946 (11)0.0254 (3)
N21.09519 (12)0.74822 (8)0.88089 (11)0.0236 (3)
N30.74122 (12)0.77434 (8)0.87076 (11)0.0233 (3)
C10.95593 (15)0.58904 (10)0.89804 (14)0.0282 (4)
C20.98845 (14)0.66220 (9)0.88872 (13)0.0221 (4)
C30.91641 (14)0.71893 (9)0.87938 (12)0.0216 (4)
C40.99049 (14)0.77333 (9)0.87439 (12)0.0214 (4)
C51.19918 (15)0.78688 (11)0.87754 (15)0.0302 (4)
H5A1.21220.80250.81220.045*
H5B1.26000.75810.89780.045*
H5C1.19390.82550.92040.045*
C60.93017 (13)0.88174 (9)0.93094 (12)0.0204 (3)
C70.89984 (14)0.94648 (9)0.90188 (13)0.0240 (4)
H70.90870.96020.83750.029*
C80.85584 (14)0.99074 (9)0.97051 (14)0.0252 (4)
H80.83531.03490.95290.030*
C90.84251 (14)0.96877 (9)1.06574 (13)0.0231 (4)
C100.87284 (13)0.90360 (9)1.09597 (13)0.0217 (4)
C110.91814 (13)0.85973 (9)1.02608 (13)0.0215 (4)
H110.94020.81581.04350.026*
C120.85611 (16)0.87976 (10)1.19861 (14)0.0293 (4)
H12A0.89180.91111.24260.044*
H12B0.88820.83511.20630.044*
H12C0.77750.87781.21280.044*
C130.79576 (14)0.71860 (9)0.87804 (13)0.0227 (4)
H130.75740.67730.88250.027*
C140.55571 (14)0.81436 (10)0.86479 (13)0.0246 (4)
C150.60736 (15)0.88311 (10)0.85610 (16)0.0309 (4)
H15A0.54960.91720.85270.046*
H15B0.65220.88500.79810.046*
H15C0.65370.89160.91190.046*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0395 (3)0.0301 (3)0.0343 (3)0.00681 (19)0.00035 (19)0.0103 (2)
F10.0363 (6)0.0256 (6)0.0646 (9)0.0072 (5)0.0057 (6)0.0028 (6)
F20.0556 (8)0.0291 (7)0.0440 (7)0.0061 (5)0.0190 (6)0.0062 (6)
F30.0475 (7)0.0326 (7)0.0446 (8)0.0076 (5)0.0115 (6)0.0049 (6)
O10.0355 (7)0.0212 (7)0.0206 (6)0.0024 (5)0.0072 (5)0.0023 (5)
O20.0190 (6)0.0244 (7)0.0328 (7)0.0022 (5)0.0000 (5)0.0013 (6)
O30.0209 (6)0.0340 (8)0.0382 (8)0.0022 (5)0.0028 (5)0.0006 (6)
N10.0260 (8)0.0245 (8)0.0259 (8)0.0014 (6)0.0005 (6)0.0024 (6)
N20.0237 (7)0.0239 (8)0.0232 (8)0.0007 (6)0.0008 (6)0.0026 (6)
N30.0172 (7)0.0284 (8)0.0243 (8)0.0022 (6)0.0002 (6)0.0002 (6)
C10.0285 (9)0.0261 (10)0.0300 (10)0.0009 (7)0.0038 (8)0.0008 (8)
C20.0228 (8)0.0224 (9)0.0211 (9)0.0010 (7)0.0004 (7)0.0019 (7)
C30.0230 (8)0.0234 (9)0.0183 (8)0.0011 (7)0.0002 (6)0.0025 (7)
C40.0255 (8)0.0230 (9)0.0158 (8)0.0026 (7)0.0017 (6)0.0015 (7)
C50.0261 (9)0.0350 (11)0.0295 (10)0.0078 (8)0.0024 (7)0.0038 (8)
C60.0194 (7)0.0210 (9)0.0208 (8)0.0014 (6)0.0006 (6)0.0018 (7)
C70.0242 (8)0.0247 (9)0.0231 (9)0.0015 (7)0.0013 (7)0.0052 (7)
C80.0240 (8)0.0195 (9)0.0321 (10)0.0019 (7)0.0046 (7)0.0011 (8)
C90.0207 (8)0.0228 (9)0.0258 (9)0.0004 (6)0.0006 (7)0.0054 (7)
C100.0183 (7)0.0249 (9)0.0219 (9)0.0030 (6)0.0015 (6)0.0003 (7)
C110.0216 (8)0.0198 (8)0.0230 (9)0.0002 (7)0.0004 (7)0.0007 (7)
C120.0318 (9)0.0332 (11)0.0230 (9)0.0005 (8)0.0019 (7)0.0009 (8)
C130.0244 (8)0.0231 (9)0.0206 (8)0.0027 (7)0.0002 (6)0.0000 (7)
C140.0237 (9)0.0285 (10)0.0216 (9)0.0012 (7)0.0019 (7)0.0009 (7)
C150.0253 (9)0.0240 (10)0.0436 (12)0.0007 (7)0.0045 (8)0.0007 (9)
Geometric parameters (Å, º) top
Cl1—C91.7425 (18)C5—H5C0.9600
F1—C11.319 (2)C6—C71.376 (2)
F2—C11.340 (2)C6—C111.382 (2)
F3—C11.341 (2)C7—C81.383 (3)
O1—C41.346 (2)C7—H70.9300
O1—C61.403 (2)C8—C91.385 (3)
O2—C141.377 (2)C8—H80.9300
O2—N31.4299 (18)C9—C101.388 (3)
O3—C141.201 (2)C10—C111.396 (2)
N1—C21.330 (2)C10—C121.497 (2)
N1—N21.351 (2)C11—H110.9300
N2—C41.347 (2)C12—H12A0.9600
N2—C51.455 (2)C12—H12B0.9600
N3—C131.274 (2)C12—H12C0.9600
C1—C21.488 (3)C13—H130.9300
C2—C31.410 (2)C14—C151.484 (3)
C3—C41.385 (3)C15—H15A0.9600
C3—C131.442 (2)C15—H15B0.9600
C5—H5A0.9600C15—H15C0.9600
C5—H5B0.9600
C14···O3i3.174 (2)Cg···Cgii3.734 (6)
C4—O1—C6119.07 (13)C6—C7—H7120.7
C14—O2—N3113.89 (13)C8—C7—H7120.7
C2—N1—N2104.05 (14)C7—C8—C9119.51 (17)
C4—N2—N1112.11 (14)C7—C8—H8120.2
C4—N2—C5127.00 (16)C9—C8—H8120.2
N1—N2—C5120.88 (15)C8—C9—C10122.46 (17)
C13—N3—O2107.97 (14)C8—C9—Cl1118.29 (14)
F1—C1—F2107.37 (16)C10—C9—Cl1119.25 (14)
F1—C1—F3107.53 (16)C9—C10—C11117.37 (16)
F2—C1—F3105.63 (15)C9—C10—C12122.14 (16)
F1—C1—C2112.99 (15)C11—C10—C12120.48 (16)
F2—C1—C2111.69 (16)C6—C11—C10119.89 (16)
F3—C1—C2111.24 (16)C6—C11—H11120.1
N1—C2—C3113.16 (16)C10—C11—H11120.1
N1—C2—C1119.65 (15)C10—C12—H12A109.5
C3—C2—C1127.19 (16)C10—C12—H12B109.5
C4—C3—C2102.59 (15)H12A—C12—H12B109.5
C4—C3—C13129.93 (17)C10—C12—H12C109.5
C2—C3—C13127.47 (17)H12A—C12—H12C109.5
O1—C4—N2119.20 (16)H12B—C12—H12C109.5
O1—C4—C3132.45 (16)N3—C13—C3120.59 (17)
N2—C4—C3108.10 (16)N3—C13—H13119.7
N2—C5—H5A109.5C3—C13—H13119.7
N2—C5—H5B109.5O3—C14—O2115.13 (17)
H5A—C5—H5B109.5O3—C14—C15126.16 (18)
N2—C5—H5C109.5O2—C14—C15118.71 (15)
H5A—C5—H5C109.5C14—C15—H15A109.5
H5B—C5—H5C109.5C14—C15—H15B109.5
C7—C6—C11122.19 (16)H15A—C15—H15B109.5
C7—C6—O1114.96 (15)C14—C15—H15C109.5
C11—C6—O1122.83 (15)H15A—C15—H15C109.5
C6—C7—C8118.57 (17)H15B—C15—H15C109.5
C2—N1—N2—C40.38 (19)C2—C3—C4—N20.22 (18)
C2—N1—N2—C5179.17 (16)C13—C3—C4—N2178.40 (17)
C14—O2—N3—C13179.70 (14)C4—O1—C6—C7168.95 (15)
N2—N1—C2—C30.2 (2)C4—O1—C6—C1112.2 (2)
N2—N1—C2—C1179.32 (16)C11—C6—C7—C80.0 (3)
F1—C1—C2—N10.6 (2)O1—C6—C7—C8178.92 (15)
F2—C1—C2—N1120.56 (18)C6—C7—C8—C90.6 (3)
F3—C1—C2—N1121.68 (18)C7—C8—C9—C100.7 (3)
F1—C1—C2—C3178.87 (17)C7—C8—C9—Cl1179.94 (13)
F2—C1—C2—C360.0 (2)C8—C9—C10—C110.1 (3)
F3—C1—C2—C357.8 (2)Cl1—C9—C10—C11179.43 (12)
N1—C2—C3—C40.0 (2)C8—C9—C10—C12178.78 (16)
C1—C2—C3—C4179.51 (17)Cl1—C9—C10—C121.8 (2)
N1—C2—C3—C13178.68 (17)C7—C6—C11—C100.7 (3)
C1—C2—C3—C130.8 (3)O1—C6—C11—C10179.45 (15)
C6—O1—C4—N2112.02 (17)C9—C10—C11—C60.6 (2)
C6—O1—C4—C374.6 (2)C12—C10—C11—C6178.15 (16)
N1—N2—C4—O1174.50 (14)O2—N3—C13—C3179.26 (15)
C5—N2—C4—O14.2 (3)C4—C3—C13—N30.5 (3)
N1—N2—C4—C30.4 (2)C2—C3—C13—N3178.78 (17)
C5—N2—C4—C3179.09 (17)N3—O2—C14—O3179.52 (15)
C2—C3—C4—O1173.74 (18)N3—O2—C14—C150.3 (2)
C13—C3—C4—O17.6 (3)
Symmetry codes: (i) x+1, y, z+3/2; (ii) x+2, y, z+3/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C5—H5B···O3iii0.962.553.102 (2)117
Symmetry code: (iii) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC15H13ClF3N3O3
Mr375.73
Crystal system, space groupOrthorhombic, Pbcn
Temperature (K)113
a, b, c (Å)11.951 (2), 19.549 (4), 13.726 (3)
V3)3206.8 (11)
Z8
Radiation typeMo Kα
µ (mm1)0.29
Crystal size (mm)0.16 × 0.12 × 0.08
Data collection
DiffractometerRigaku Saturn
diffractometer
Absorption correctionMulti-scan
(CrystalClear; Rigaku, 2008)
Tmin, Tmax0.955, 0.977
No. of measured, independent and
observed [I > 2σ(I)] reflections
21575, 3686, 3208
Rint0.061
(sin θ/λ)max1)0.651
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.046, 0.115, 1.10
No. of reflections3686
No. of parameters229
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.29, 0.33

Computer programs: CrystalClear (Rigaku, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C5—H5B···O3i0.9602.5473.102 (2)117
Symmetry code: (i) x+1, y, z.
 

Acknowledgements

This work was supported by the Science and Technology Projects Fund of Nantong City (grant Nos. K2010016, AS2010005), the Science Foundation of Nantong University (grant Nos. 09Z010, 09 C001) and the Scientific Research Foundation for Talent Introduction of Nantong University.

References

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