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ISSN: 2056-9890

Methyl 2-(5-fluoro-3-methyl­sulfinyl-1-benzo­furan-2-yl)acetate

aDepartment of Chemistry, Dongeui University, San 24 Kaya-dong Busanjin-gu, Busan 614-714, Republic of Korea, and bDepartment of Chemistry, Pukyong National University, 599-1 Daeyeon 3-dong, Nam-gu, Busan 608-737, Republic of Korea
*Correspondence e-mail: uklee@pknu.ac.kr

(Received 21 July 2009; accepted 31 July 2009; online 8 August 2009)

In the title compound, C12H11FO4S, the O atom and the methyl group of the methyl­sulfinyl substituent lie on opposite sides of the plane of the benzofuran fragment [O—S—C—C and C—S—C—C torsion angles = 126.70 (13) and −123.55 (13)°, respectively]. The crystal structure is stabilized by weak non-classical inter­molecular C—H⋯O hydrogen-bond inter­actions. The crystal structure also exhibits aromatic ππ stacking inter­actions between furan/benzene and benzene/benzene rings of adjacent benzofuran ring systems [centroid–centroid distances = 3.8258 (9) and 3.8794 (9) Å] and a weak inter­molecular C—H⋯π ring inter­action.

Related literature

For crystal structures of similar methyl 2-(5-halo-3-methyl­sulfinyl-1-benzofuran-2-yl)acetate derivatives. see: Choi et al. (2008a[Choi, H. D., Seo, P. J., Son, B. W. & Lee, U. (2008a). Acta Cryst. E64, o2139.],b[Choi, H. D., Seo, P. J., Son, B. W. & Lee, U. (2008b). Acta Cryst. E64, o2397.]). For the pharmacological properties of benzofuran compounds, see: Howlett et al. (1999[Howlett, D. R., Perry, A. E., Godfrey, F., Swatton, J. E., Jennings, K. H., Spitzfaden, C., Wadsworth, H., Wood, S. J. & Markwell, R. E. (1999). Biochem. J. 340, 283-289.]); Twyman & Allsop (1999[Twyman, L. J. & Allsop, D. (1999). Tetrahedron Lett. 40, 9383-9384.]).

[Scheme 1]

Experimental

Crystal data
  • C12H11FO4S

  • Mr = 270.27

  • Triclinic, [P \overline 1]

  • a = 7.7799 (5) Å

  • b = 8.5609 (6) Å

  • c = 10.5592 (7) Å

  • α = 73.834 (1)°

  • β = 80.178 (1)°

  • γ = 67.486 (1)°

  • V = 622.36 (7) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.28 mm−1

  • T = 273 K

  • 0.60 × 0.40 × 0.40 mm

Data collection
  • Bruker SMART CCD diffractometer

  • Absorption correction: none

  • 5368 measured reflections

  • 2667 independent reflections

  • 2389 reflections with I > 2σ(I)

  • Rint = 0.014

Refinement
  • R[F2 > 2σ(F2)] = 0.032

  • wR(F2) = 0.089

  • S = 1.08

  • 2667 reflections

  • 165 parameters

  • H-atom parameters constrained

  • Δρmax = 0.28 e Å−3

  • Δρmin = −0.31 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C3—H3⋯O4i 0.93 2.39 3.303 (2) 166
C9—H9A⋯O4ii 0.97 2.22 3.179 (2) 168
C9—H9B⋯O1iii 0.97 2.54 3.489 (2) 166
C12—H12A⋯O3iv 0.96 2.60 3.478 (2) 152
C11—H11ACg2v 0.96 2.97 3.93 173
Symmetry codes: (i) -x+1, -y+1, -z; (ii) -x+2, -y+1, -z; (iii) -x+2, -y+1, -z+1; (iv) -x+1, -y+2, -z; (v) x, y+1, z. Cg2 is the centroid of the C2–C7 ring.

Data collection: SMART (Bruker, 2001[Bruker (2001). SAINT and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2001[Bruker (2001). SAINT and SMART. Bruker 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: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and DIAMOND (Brandenburg, 1998[Brandenburg, K. (1998). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Molecules containing the benzofuran skeleton have received considerable attention related to their pharmacological properties (Howlett et al., 1999; Twyman & Allsop, 1999). This work is related to our communications on the synthesis and crystal structures of methyl 2-(5-halo-3-methylsulfinyl-1-benzofuran-2-yl)acetate derivatives, viz. methyl 2-(5-chloro-3-methylsulfinyl-1-benzofuran-2-yl)acetate (Choi et al., 2008a), and methyl 2-(5-bromo-3-methylsulfinyl-1-benzofuran-2-yl)acetate (Choi et al., 2008b). Here we report the crystal structure of the title compound, methyl 2-(5-fluoro-3-methylsulfinyl-1-benzofuran-2-yl)acetate (Fig. 1).

The benzofuran unit is essentially planar, with a mean deviation of 0.006 (1) ° from the least-squares plane defined by the nine constituent atoms (Fig. 1). In the title compound, all of the bond angles and bond distances are in the normal range of related molecules (Choi et al., 2008a, b). The oxygen atom and the methyl group of the methylsulfinyl substituent lie on opposite sides of the plane of the benzofuran fragment [O4–S–C1–C8 and C12–S–C1–C8 torsional angles = 126.70 (13)° and -123.55 (13) °, respectively]. Crystal packing is stabilized by weak intermolecular C–H···O hydrogen bond interactions involving the SO unit with the benzofurn ring (C3–H3···O4i) and a methylene H atom (C9–H9A···O4ii), between the furan ring and methylene H atom (C9–H9B···O1iii) as well as between a methyl H atom of the methylsulfinyl substituent and the CO unit (C12–H12A···O3iv), respectively (Fig. 2, Table 1). Crystal packing also exhibits aromatic ππ stacking interactions between the furan/benzene and the benzene/benzene rings of neighbouring molecules [Cg1···Cg2vii = 3.8258 (9)Å and Cg2···Cg2vi = 3.8794 (9)Å, where Cg1 and Cg2 are centroids of the furan (C1/C2/C7/O1/C8) and benzene (C2-C7) rings, respectively, Fig. 3]. The molecular packing is further stabilized by a weak, intermolecular C–H···π ring interaction between a methyl H atom of the methoxy group and a benzene ring of a neighbouring molecule (C11–H11A···Cg2v; = 3.927 (3)Å, Table 1).

Related literature top

For crystal structures of similar methyl 2-(5-halo-3-methylsulfinyl-1-benzofuran-2-yl)acetate derivatives. see: Choi et al. (2008a,b). For pharmacological properties of benzofuran compounds, see: Howlett et al. (1999); Twyman & Allsop (1999). Cg2 is the

centroid of the C2–C7 rings.

Experimental top

The 77% 3-chloroperoxybenzoic acid (247 mg, 1.1 mmol) was added in small portions to a stirred solution of methyl 2-(5-fluoro-3-methylsulfanyl-1-benzofuran-2-yl)acetate (254 mg, 1.0 mmol) in dichloromethane (30 ml) at 273 K. After being stirred for 4 h at room temperature, the mixture was washed with saturated sodium bicarbonate solution and the organic layer was separated, dried over magnesium sulfate, filtered and concentrated in vacuum. The residue was purified by column chromatography (hexane-ethyl acetate,1:2 v/v) to afford the title compound as a colorless solid [yield 79%, m.p. 370-371 K; Rf = 0.4 (hexane-ethyl acetate, 1;2 v/v )]. Single crystals suitable for X-ray diffraction were prepared by slow evaporation of a solution of the title compound in benzene at room temperature.

Refinement top

All H atoms were geometrically positioned and refined using a riding model, with C–H = 0.93 Å for the aryl, 0.97 Å for the methylene, and 0.96 Å for the methyl H atoms. Uiso(H) = 1.2 Ueq(C) for the aryl and methylene H atoms, and 1.5 Ueq(C) for methyl H atoms.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); 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, 1998); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are presented as a small cycles of arbitrary radius.
[Figure 2] Fig. 2. Weak, C–H···O hydrogen bond interactions (dotted lines) in the title compound. [Symmetry code: (i) - x + 1, - y + 1, - z; (ii) - x + 2, - y + 1, - z; (iii) - x + 2, - y + 1, - z + 1; (iv) - x+1, - y + 2, - z.]
[Figure 3] Fig. 3. Weak, ππ stacking and C–H···π ring intermoleclar interactions (dotted lines) in the title compound. Cg1 and C2 denote ring centroids for C1/C2/C7/O1/C8 and C2-C7, respectively.[Symmetry code: (v) x, y + 1, z; (vi) - x + 1, - y + 2 , - z + 1; 1-x, 2-y, (vii) - x + 1, - y + 1, - z + 1.]
Methyl 2-(5-fluoro-3-methylsulfinyl-1-benzofuran-2-yl)acetate top
Crystal data top
C12H11FO4SZ = 2
Mr = 270.27F(000) = 280
Triclinic, P1Dx = 1.442 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.7799 (5) ÅCell parameters from 3896 reflections
b = 8.5609 (6) Åθ = 2.7–27.5°
c = 10.5592 (7) ŵ = 0.28 mm1
α = 73.834 (1)°T = 273 K
β = 80.178 (1)°Block, colorless
γ = 67.486 (1)°0.60 × 0.40 × 0.40 mm
V = 622.36 (7) Å3
Data collection top
Bruker SMART CCD
diffractometer
2389 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.014
Graphite monochromatorθmax = 27.0°, θmin = 2.0°
Detector resolution: 10.0 pixels mm-1h = 99
ϕ and ω scansk = 1010
5368 measured reflectionsl = 1313
2667 independent reflections
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)] = 0.032Hydrogen site location: difference Fourier map
wR(F2) = 0.089H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.0432P)2 + 0.227P]
where P = (Fo2 + 2Fc2)/3
2667 reflections(Δ/σ)max = 0.001
165 parametersΔρmax = 0.28 e Å3
0 restraintsΔρmin = 0.31 e Å3
Crystal data top
C12H11FO4Sγ = 67.486 (1)°
Mr = 270.27V = 622.36 (7) Å3
Triclinic, P1Z = 2
a = 7.7799 (5) ÅMo Kα radiation
b = 8.5609 (6) ŵ = 0.28 mm1
c = 10.5592 (7) ÅT = 273 K
α = 73.834 (1)°0.60 × 0.40 × 0.40 mm
β = 80.178 (1)°
Data collection top
Bruker SMART CCD
diffractometer
2389 reflections with I > 2σ(I)
5368 measured reflectionsRint = 0.014
2667 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0320 restraints
wR(F2) = 0.089H-atom parameters constrained
S = 1.08Δρmax = 0.28 e Å3
2667 reflectionsΔρmin = 0.31 e Å3
165 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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
S0.73212 (5)0.63256 (5)0.04928 (3)0.03039 (12)
F0.30035 (14)0.21264 (13)0.37311 (11)0.0513 (3)
O10.84250 (14)0.43881 (13)0.42317 (9)0.0288 (2)
O21.04499 (16)0.88742 (15)0.21928 (13)0.0436 (3)
O30.75373 (16)0.90527 (15)0.20563 (13)0.0449 (3)
O40.75098 (17)0.49556 (16)0.02040 (11)0.0415 (3)
C10.73869 (19)0.53270 (18)0.21918 (13)0.0263 (3)
C20.63718 (19)0.42498 (17)0.29942 (13)0.0261 (3)
C30.4978 (2)0.37061 (19)0.27953 (15)0.0309 (3)
H30.44800.40360.19810.037*
C40.4390 (2)0.26551 (19)0.38775 (17)0.0352 (3)
C50.5098 (2)0.2096 (2)0.51151 (16)0.0375 (4)
H50.46410.13770.58040.045*
C60.6489 (2)0.26217 (19)0.53113 (15)0.0342 (3)
H60.70000.22680.61240.041*
C70.70799 (19)0.36995 (18)0.42381 (14)0.0275 (3)
C80.85804 (19)0.53640 (18)0.29708 (13)0.0264 (3)
C90.9967 (2)0.62392 (19)0.27115 (14)0.0290 (3)
H9A1.08860.58160.20240.035*
H9B1.06110.59190.35060.035*
C100.9129 (2)0.82024 (19)0.22925 (14)0.0296 (3)
C110.9865 (3)1.0754 (2)0.1780 (3)0.0657 (6)
H11A0.93331.11470.09410.099*
H11B1.09241.10990.17010.099*
H11C0.89501.12610.24250.099*
C120.4904 (2)0.7705 (2)0.04906 (17)0.0386 (4)
H12A0.46250.83930.03880.058*
H12B0.46560.84580.10770.058*
H12C0.41390.70000.07820.058*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S0.0313 (2)0.0392 (2)0.02016 (18)0.01352 (15)0.00616 (13)0.00224 (14)
F0.0428 (6)0.0440 (6)0.0702 (7)0.0247 (5)0.0127 (5)0.0003 (5)
O10.0340 (5)0.0313 (5)0.0211 (5)0.0111 (4)0.0076 (4)0.0034 (4)
O20.0324 (6)0.0323 (6)0.0661 (8)0.0123 (5)0.0036 (5)0.0104 (5)
O30.0323 (6)0.0356 (6)0.0588 (8)0.0086 (5)0.0120 (5)0.0019 (5)
O40.0454 (7)0.0528 (7)0.0277 (6)0.0129 (5)0.0069 (5)0.0154 (5)
C10.0278 (7)0.0284 (7)0.0209 (6)0.0074 (5)0.0053 (5)0.0046 (5)
C20.0270 (7)0.0249 (6)0.0237 (6)0.0050 (5)0.0036 (5)0.0065 (5)
C30.0294 (7)0.0285 (7)0.0334 (7)0.0070 (6)0.0071 (6)0.0069 (6)
C40.0295 (7)0.0278 (7)0.0477 (9)0.0100 (6)0.0051 (6)0.0065 (6)
C50.0389 (8)0.0275 (7)0.0382 (8)0.0103 (6)0.0018 (6)0.0000 (6)
C60.0403 (8)0.0299 (7)0.0261 (7)0.0082 (6)0.0043 (6)0.0017 (6)
C70.0283 (7)0.0267 (7)0.0261 (7)0.0065 (5)0.0045 (5)0.0070 (5)
C80.0276 (7)0.0264 (7)0.0217 (6)0.0055 (5)0.0048 (5)0.0041 (5)
C90.0265 (7)0.0315 (7)0.0285 (7)0.0078 (6)0.0080 (5)0.0061 (5)
C100.0302 (7)0.0338 (7)0.0238 (7)0.0112 (6)0.0019 (5)0.0055 (5)
C110.0528 (12)0.0333 (9)0.1083 (19)0.0182 (9)0.0025 (12)0.0103 (10)
C120.0349 (8)0.0362 (8)0.0382 (8)0.0074 (6)0.0134 (6)0.0001 (6)
Geometric parameters (Å, º) top
S—O41.500 (2)C4—C51.391 (2)
S—C11.760 (1)C5—C61.385 (2)
S—C121.797 (2)C5—H50.9300
F—C41.365 (2)C6—C71.383 (2)
O1—C81.374 (2)C6—H60.9300
O1—C71.382 (2)C8—C91.484 (2)
O2—C101.335 (2)C9—C101.514 (2)
O2—C111.450 (2)C9—H9A0.9700
O3—C101.200 (2)C9—H9B0.9700
C1—C81.355 (2)C11—H11A0.9600
C1—C21.444 (2)C11—H11B0.9600
C2—C71.398 (2)C11—H11C0.9600
C2—C31.398 (2)C12—H12A0.9600
C3—C41.374 (2)C12—H12B0.9600
C3—H30.9300C12—H12C0.9600
O4—S—C1106.58 (7)C6—C7—C2123.8 (1)
O4—S—C12106.22 (8)C1—C8—O1111.2 (1)
C1—S—C1298.29 (7)C1—C8—C9132.4 (1)
C8—O1—C7106.3 (1)O1—C8—C9116.5 (1)
C10—O2—C11116.0 (1)C8—C9—C10114.0 (1)
C8—C1—C2107.3 (1)C8—C9—H9A108.8
C8—C1—S123.2 (1)C10—C9—H9A108.8
C2—C1—S129.4 (1)C8—C9—H9B108.8
C7—C2—C3119.5 (1)C10—C9—H9B108.8
C7—C2—C1104.8 (1)H9A—C9—H9B107.7
C3—C2—C1135.8 (1)O3—C10—O2124.1 (1)
C4—C3—C2115.9 (1)O3—C10—C9126.4 (1)
C4—C3—H3122.1O2—C10—C9109.5 (1)
C2—C3—H3122.1O2—C11—H11A109.5
F—C4—C3117.7 (1)O2—C11—H11B109.5
F—C4—C5117.5 (1)H11A—C11—H11B109.5
C3—C4—C5124.8 (2)O2—C11—H11C109.5
C6—C5—C4119.4 (1)H11A—C11—H11C109.5
C6—C5—H5120.3H11B—C11—H11C109.5
C4—C5—H5120.3S—C12—H12A109.5
C7—C6—C5116.6 (1)S—C12—H12B109.5
C7—C6—H6121.7H12A—C12—H12B109.5
C5—C6—H6121.7S—C12—H12C109.5
O1—C7—C6125.7 (1)H12A—C12—H12C109.5
O1—C7—C2110.5 (1)H12B—C12—H12C109.5
O4—S—C1—C8126.70 (13)C5—C6—C7—C20.8 (2)
C12—S—C1—C8123.55 (13)C3—C2—C7—O1179.47 (12)
O4—S—C1—C248.22 (14)C1—C2—C7—O10.62 (15)
C12—S—C1—C261.53 (14)C3—C2—C7—C60.3 (2)
C8—C1—C2—C70.35 (15)C1—C2—C7—C6179.62 (13)
S—C1—C2—C7175.19 (11)C2—C1—C8—O10.04 (16)
C8—C1—C2—C3179.77 (15)S—C1—C8—O1175.92 (9)
S—C1—C2—C34.7 (2)C2—C1—C8—C9179.96 (14)
C7—C2—C3—C40.6 (2)S—C1—C8—C94.2 (2)
C1—C2—C3—C4179.54 (15)C7—O1—C8—C10.42 (15)
C2—C3—C4—F178.65 (12)C7—O1—C8—C9179.65 (12)
C2—C3—C4—C51.0 (2)C1—C8—C9—C1061.1 (2)
F—C4—C5—C6179.15 (14)O1—C8—C9—C10118.82 (13)
C3—C4—C5—C60.5 (2)C11—O2—C10—O30.5 (2)
C4—C5—C6—C70.4 (2)C11—O2—C10—C9179.20 (16)
C8—O1—C7—C6179.59 (14)C8—C9—C10—O36.6 (2)
C8—O1—C7—C20.65 (14)C8—C9—C10—O2174.75 (12)
C5—C6—C7—O1178.93 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···O4i0.932.393.303 (2)166
C9—H9A···O4ii0.972.223.179 (2)168
C9—H9B···O1iii0.972.543.489 (2)166
C12—H12A···O3iv0.962.603.478 (2)152
C11—H11A···Cg2v0.962.973.93173
Symmetry codes: (i) x+1, y+1, z; (ii) x+2, y+1, z; (iii) x+2, y+1, z+1; (iv) x+1, y+2, z; (v) x, y+1, z.

Experimental details

Crystal data
Chemical formulaC12H11FO4S
Mr270.27
Crystal system, space groupTriclinic, P1
Temperature (K)273
a, b, c (Å)7.7799 (5), 8.5609 (6), 10.5592 (7)
α, β, γ (°)73.834 (1), 80.178 (1), 67.486 (1)
V3)622.36 (7)
Z2
Radiation typeMo Kα
µ (mm1)0.28
Crystal size (mm)0.60 × 0.40 × 0.40
Data collection
DiffractometerBruker SMART CCD
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
5368, 2667, 2389
Rint0.014
(sin θ/λ)max1)0.638
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.032, 0.089, 1.08
No. of reflections2667
No. of parameters165
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.28, 0.31

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1998).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···O4i0.932.393.303 (2)166.0
C9—H9A···O4ii0.972.223.179 (2)168.2
C9—H9B···O1iii0.972.543.489 (2)166.2
C12—H12A···O3iv0.962.603.478 (2)152.0
C11—H11A···Cg2v0.962.973.93173.3
Symmetry codes: (i) x+1, y+1, z; (ii) x+2, y+1, z; (iii) x+2, y+1, z+1; (iv) x+1, y+2, z; (v) x, y+1, z.
 

References

First citationBrandenburg, K. (1998). DIAMOND. Crystal Impact GbR, Bonn, Germany.  Google Scholar
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