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ISSN: 2056-9890

5-Iso­propyl-2-methyl-3-phenyl­sulfonyl-1-benzo­furan

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 2 May 2008; accepted 8 June 2008; online 13 June 2008)

The title compound, C18H18O3S, was prepared by the oxidation of 5-isopropyl-2-methyl-3-phenyl­sulfanyl-1-benzofuran with 3-chloro­peroxy­benzoic acid. The phenyl ring makes a dihedral angle of 79.37 (6)° with the plane of the benzofuran fragment. The crystal structure is stabilized by aromatic ππ stacking inter­actions between the benzene and furan rings of neighbouring mol­ecules [centroid–centroid distance = 3.762 (3) Å]. In addition, the stacked mol­ecules exhibit C—H⋯π and intra­molecular C—H⋯O inter­actions.

Related literature

For the crystal structures of similar 2-methyl-3-phenyl­sulfonyl-1-benzofuran compounds, see: Choi et al. (2008a[Choi, H. D., Seo, P. J., Son, B. W. & Lee, U. (2008a). Acta Cryst. E64, o794.],b[Choi, H. D., Seo, P. J., Son, B. W. & Lee, U. (2008b). Acta Cryst. E64, o850.]).

[Scheme 1]

Experimental

Crystal data
  • C18H18O3S

  • Mr = 314.38

  • Monoclinic, P 21 /c

  • a = 10.736 (1) Å

  • b = 13.024 (1) Å

  • c = 11.729 (1) Å

  • β = 99.655 (2)°

  • V = 1616.8 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.21 mm−1

  • T = 173 (2) K

  • 0.60 × 0.40 × 0.40 mm

Data collection
  • Bruker SMART CCD diffractometer

  • Absorption correction: none

  • 9705 measured reflections

  • 3505 independent reflections

  • 3008 reflections with I > 2σ(I)

  • Rint = 0.066

Refinement
  • R[F2 > 2σ(F2)] = 0.049

  • wR(F2) = 0.127

  • S = 0.98

  • 3505 reflections

  • 200 parameters

  • H-atom parameters constrained

  • Δρmax = 0.25 e Å−3

  • Δρmin = −0.53 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C6—H6⋯Cg3i 0.95 2.65 3.516 (3) 152
C18—H18A⋯O2 0.98 2.39 3.119 (3) 131
C10—H10⋯O2 0.95 2.58 2.938 (2) 103
Symmetry code: (i) -x+1, -y+1, -z+1. Cg3 is the centroid of the C9—C14 phenyl 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

As a part of our ongoing studies on the synthesis and structure of 2-methyl-3-phenylsulfonyl-1-benzofuran analogues, the crystal structure of 2,5,7-trimethyl-3-phenylsulfonyl-1-benzofuran (Choi et al., 2008a) and 2,5-dimethyl-3-phenylsulfonyl-1-benzofuran (Choi et al., 2008b) have been described in the literature. Here we report the crystal structure of the title compound, 5-isopropyl-2-methyl-3-phenylsulfonyl-1-benzofuran (Fig. 1).

The benzofuran unit is essentially planar, with a mean deviation of 0.01° from the least-squares plane defined by the nine constituent atoms. The phenyl ring (C9—C14) makes a dihedral angle of 79.37 (6)° with the plane of the benzofuran fragment. The crystal packing (Fig. 2) is stabilized by aromatic ππ stacking interactions between the benzene ring and the furan ring of neighbouring molecules. The Cg1···Cg2i distance is 3.762 (3) Å (Cg1 and Cg2 are the centroids of the C2—C7 benzene ring and the O1/C8/C1/C2/C7 furan ring, respectively, symmetry code as in Fig. 2). The molecular packing (Fig. 2) is further stabilized by the C—H···π interactions between a benzene H atom of the benzofuran system and the phenyl ring of the phenylsulfonyl substitutent, with a C6—H6···Cg3i separation of 2.65 Å (Fig. 2 and Table 1; Cg3 is the centroid of the C9—C14 phenyl ring, symmetry code as in Fig. 2). Additionally, intramolecular C—H···O interactions in the structure were observed (Fig. 2 and Table 1; symmetry code as in Fig. 2).

Related literature top

For the crystal structures of similar 2-methyl-3-phenylsulfonyl-1-benzofuran compounds, see: Choi et al. (2008a,b). Cg3 is the centroid of the C9—C14 phenyl ring,

Experimental top

3-Chloroperoxybenzoic acid (77%, 471 mg, 2.1 mmol) was added in small portions to a stirred solution of 5-isopropyl-2-methyl-3-phenylsulfanyl-1-benzofuran (282 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, 2:1 v/v) to afford the title compound as a colorless solid [yield 81%, m.p. 386–387 K; Rf = 0.79 (hexane-ethyl acetate, 1:1 v/v)]. Single crystals suitable for X-ray diffraction were prepared by evaporation of a solution of the title compound in acetone at room temperature. Spectroscopic analysis: 1H NMR (CDCl3, 400 MHz) δ 1.28 (d, J = 6.96 Hz, 6H), 2.79 (s, 3H), 2.91–3.07 (m, 1H), 7.18 (dd, J = 8.44 Hz and 1.48 Hz, 1H), 7.33 (d, J = 8.40 Hz, 1H), 7.45–7.57 (m, 3H), 7.69 (s, 1H), 8.01 (dd, J = 6.96 Hz and 1.84 Hz, 2H); EI—MS 314 [M+].

Refinement top

All H atoms were positioned geometrically and refined using a riding model, with C—H = 0.95 Å for aromatic H atoms, 1.00 Å for methine H atom and 0.98 Å for methyl H atoms, respectively, and with Uiso(H) = 1.2Ueq(C) for aromatic and methine, and 1.5Ueq(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, showing displacement ellipsoides drawn at the 50% probability level.
[Figure 2] Fig. 2. ππ, C—H···π and C—H···O interactions (dotted lines) in the title compound. Cg denotes the ring centroids. [Symmetry code: (i) -x + 1, -y + 1, -z + 1.]
5-Isopropyl-2-methyl-3-phenylsulfonyl-1-benzofuran top
Crystal data top
C18H18O3SF(000) = 664
Mr = 314.38Dx = 1.292 Mg m3
Monoclinic, P21/cMelting point = 386–387 K
Hall symbol: -p 2ybcMo Kα radiation, λ = 0.71073 Å
a = 10.736 (1) ÅCell parameters from 5849 reflections
b = 13.024 (1) Åθ = 2.4–28.1°
c = 11.729 (1) ŵ = 0.21 mm1
β = 99.655 (2)°T = 173 K
V = 1616.8 (2) Å3Block, colorless
Z = 40.60 × 0.40 × 0.40 mm
Data collection top
Bruker SMART CCD
diffractometer
3008 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.066
Graphite monochromatorθmax = 27.0°, θmin = 2.5°
Detector resolution: 10.0 pixels mm-1h = 1313
ϕ and ω scansk = 1516
9705 measured reflectionsl = 1314
3505 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)] = 0.049Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.127H-atom parameters constrained
S = 0.98 w = 1/[σ2(Fo2) + (0.061P)2 + 1.3518P]
where P = (Fo2 + 2Fc2)/3
3505 reflections(Δ/σ)max = 0.001
200 parametersΔρmax = 0.25 e Å3
0 restraintsΔρmin = 0.53 e Å3
Crystal data top
C18H18O3SV = 1616.8 (2) Å3
Mr = 314.38Z = 4
Monoclinic, P21/cMo Kα radiation
a = 10.736 (1) ŵ = 0.21 mm1
b = 13.024 (1) ÅT = 173 K
c = 11.729 (1) Å0.60 × 0.40 × 0.40 mm
β = 99.655 (2)°
Data collection top
Bruker SMART CCD
diffractometer
3008 reflections with I > 2σ(I)
9705 measured reflectionsRint = 0.066
3505 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0490 restraints
wR(F2) = 0.127H-atom parameters constrained
S = 0.98Δρmax = 0.25 e Å3
3505 reflectionsΔρmin = 0.53 e Å3
200 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
S0.83554 (4)0.69176 (3)0.55320 (4)0.02524 (15)
O10.46657 (13)0.66684 (10)0.47014 (12)0.0288 (3)
O20.84305 (15)0.79303 (10)0.60360 (13)0.0360 (4)
O30.90954 (14)0.66788 (11)0.46512 (12)0.0328 (3)
C10.67826 (18)0.66590 (13)0.49602 (15)0.0239 (4)
C20.63435 (17)0.58971 (13)0.40821 (15)0.0224 (4)
C30.68980 (17)0.52023 (13)0.34157 (16)0.0247 (4)
H30.77910.51530.34930.030*
C40.61150 (18)0.45785 (14)0.26310 (17)0.0273 (4)
C50.47968 (19)0.46738 (15)0.25280 (17)0.0294 (4)
H50.42750.42510.19860.035*
C60.42262 (18)0.53572 (14)0.31820 (17)0.0285 (4)
H60.33340.54170.31010.034*
C70.50303 (17)0.59463 (13)0.39592 (15)0.0241 (4)
C80.5751 (2)0.70820 (14)0.53031 (17)0.0285 (4)
C90.87264 (17)0.60205 (13)0.66639 (15)0.0231 (4)
C100.85507 (18)0.62898 (15)0.77698 (16)0.0287 (4)
H100.82690.69590.79240.034*
C110.8793 (2)0.55655 (17)0.86501 (17)0.0330 (4)
H110.86570.57320.94080.040*
C120.92341 (19)0.45979 (16)0.84182 (18)0.0327 (4)
H120.94010.41050.90220.039*
C130.94327 (18)0.43436 (15)0.73172 (17)0.0300 (4)
H130.97520.36840.71720.036*
C140.91658 (17)0.50522 (14)0.64226 (16)0.0255 (4)
H140.92810.48790.56610.031*
C150.6668 (2)0.38118 (17)0.1882 (2)0.0391 (5)
H150.59620.33560.15170.047*
C160.7664 (3)0.3128 (2)0.2585 (3)0.0692 (9)
H16A0.72830.27450.31580.083*
H16B0.83560.35540.29820.083*
H16C0.79930.26450.20680.083*
C170.7186 (3)0.4350 (2)0.0905 (3)0.0668 (9)
H17A0.78510.48330.12340.080*
H17B0.65030.47250.04200.080*
H17C0.75380.38390.04350.080*
C180.5557 (2)0.78612 (17)0.6181 (2)0.0409 (5)
H18A0.63740.81550.65250.061*
H18B0.51660.75360.67860.061*
H18C0.50040.84070.58100.061*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S0.0298 (3)0.0207 (2)0.0246 (2)0.00658 (17)0.00273 (18)0.00024 (16)
O10.0279 (7)0.0279 (7)0.0305 (7)0.0059 (5)0.0044 (5)0.0014 (5)
O20.0483 (9)0.0211 (7)0.0376 (8)0.0101 (6)0.0040 (7)0.0042 (6)
O30.0331 (8)0.0362 (8)0.0300 (7)0.0074 (6)0.0079 (6)0.0017 (6)
C10.0303 (9)0.0194 (8)0.0213 (8)0.0009 (7)0.0017 (7)0.0027 (6)
C20.0253 (9)0.0193 (8)0.0218 (8)0.0015 (7)0.0013 (7)0.0044 (6)
C30.0221 (8)0.0225 (8)0.0290 (9)0.0016 (7)0.0025 (7)0.0006 (7)
C40.0283 (10)0.0225 (9)0.0305 (10)0.0037 (7)0.0036 (8)0.0014 (7)
C50.0286 (10)0.0273 (9)0.0303 (10)0.0069 (8)0.0007 (8)0.0002 (7)
C60.0216 (9)0.0305 (9)0.0322 (10)0.0010 (7)0.0007 (8)0.0058 (8)
C70.0262 (9)0.0224 (8)0.0237 (9)0.0042 (7)0.0040 (7)0.0062 (7)
C80.0355 (10)0.0223 (9)0.0268 (9)0.0028 (7)0.0029 (8)0.0039 (7)
C90.0216 (8)0.0241 (8)0.0228 (9)0.0049 (7)0.0018 (7)0.0001 (7)
C100.0284 (10)0.0299 (9)0.0261 (9)0.0010 (8)0.0004 (7)0.0044 (7)
C110.0319 (10)0.0440 (11)0.0212 (9)0.0011 (9)0.0012 (8)0.0002 (8)
C120.0284 (10)0.0388 (11)0.0289 (10)0.0025 (8)0.0015 (8)0.0076 (8)
C130.0231 (9)0.0305 (10)0.0359 (10)0.0026 (7)0.0039 (8)0.0028 (8)
C140.0217 (8)0.0286 (9)0.0266 (9)0.0023 (7)0.0048 (7)0.0018 (7)
C150.0326 (11)0.0333 (11)0.0517 (13)0.0065 (8)0.0078 (10)0.0198 (9)
C160.0556 (17)0.0461 (15)0.101 (2)0.0171 (13)0.0013 (17)0.0282 (15)
C170.080 (2)0.0640 (18)0.0664 (18)0.0203 (15)0.0404 (16)0.0332 (15)
C180.0482 (13)0.0337 (11)0.0420 (12)0.0074 (10)0.0111 (10)0.0087 (9)
Geometric parameters (Å, º) top
S—O31.439 (2)C10—C111.390 (3)
S—O21.442 (1)C10—H100.9500
S—C11.742 (2)C11—C121.389 (3)
S—C91.763 (2)C11—H110.9500
O1—C81.367 (2)C12—C131.384 (3)
O1—C71.382 (2)C12—H120.9500
C1—C81.357 (3)C13—C141.391 (3)
C1—C21.451 (2)C13—H130.9500
C2—C71.394 (3)C14—H140.9500
C2—C31.393 (3)C15—C161.524 (4)
C3—C41.398 (3)C15—C171.525 (4)
C3—H30.9500C15—H151.0000
C4—C51.406 (3)C16—H16A0.9800
C4—C151.515 (3)C16—H16B0.9800
C5—C61.383 (3)C16—H16C0.9800
C5—H50.9500C17—H17A0.9800
C6—C71.379 (3)C17—H17B0.9800
C6—H60.9500C17—H17C0.9800
C8—C181.485 (3)C18—H18A0.9800
C9—C101.387 (3)C18—H18B0.9800
C9—C141.392 (3)C18—H18C0.9800
O3—S—O2119.50 (9)C10—C11—C12119.8 (2)
O3—S—C1107.34 (9)C10—C11—H11120.1
O2—S—C1108.58 (9)C12—C11—H11120.1
O3—S—C9108.37 (9)C13—C12—C11120.7 (2)
O2—S—C9107.90 (9)C13—C12—H12119.6
C1—S—C9104.11 (8)C11—C12—H12119.6
C8—O1—C7106.6 (2)C12—C13—C14120.1 (2)
C8—C1—C2107.7 (2)C12—C13—H13120.0
C8—C1—S126.5 (2)C14—C13—H13120.0
C2—C1—S125.7 (1)C13—C14—C9118.8 (2)
C7—C2—C3119.5 (2)C13—C14—H14120.6
C7—C2—C1104.2 (2)C9—C14—H14120.6
C3—C2—C1136.4 (2)C4—C15—C16112.2 (2)
C2—C3—C4118.7 (2)C4—C15—C17111.1 (2)
C2—C3—H3120.6C16—C15—C17111.4 (3)
C4—C3—H3120.6C4—C15—H15107.3
C5—C4—C3119.4 (2)C16—C15—H15107.3
C5—C4—C15119.7 (2)C17—C15—H15107.3
C3—C4—C15120.9 (2)C15—C16—H16A109.5
C6—C5—C4122.8 (2)C15—C16—H16B109.5
C6—C5—H5118.6H16A—C16—H16B109.5
C4—C5—H5118.6C15—C16—H16C109.5
C5—C6—C7116.0 (2)H16A—C16—H16C109.5
C5—C6—H6122.0H16B—C16—H16C109.5
C7—C6—H6122.0C15—C17—H17A109.5
C6—C7—O1125.7 (2)C15—C17—H17B109.5
C6—C7—C2123.6 (2)H17A—C17—H17B109.5
O1—C7—C2110.8 (2)C15—C17—H17C109.5
C1—C8—O1110.8 (2)H17A—C17—H17C109.5
C1—C8—C18134.4 (2)H17B—C17—H17C109.5
O1—C8—C18114.9 (2)C8—C18—H18A109.5
C10—C9—C14121.6 (2)C8—C18—H18B109.5
C10—C9—S119.2 (1)H18A—C18—H18B109.5
C14—C9—S119.3 (1)C8—C18—H18C109.5
C9—C10—C11119.0 (2)H18A—C18—H18C109.5
C9—C10—H10120.5H18B—C18—H18C109.5
C11—C10—H10120.5
O3—S—C1—C8155.70 (16)C2—C1—C8—O11.1 (2)
O2—S—C1—C825.23 (19)S—C1—C8—O1177.24 (12)
C9—S—C1—C889.53 (18)C2—C1—C8—C18177.6 (2)
O3—S—C1—C228.81 (17)S—C1—C8—C181.5 (3)
O2—S—C1—C2159.29 (15)C7—O1—C8—C10.7 (2)
C9—S—C1—C285.95 (16)C7—O1—C8—C18178.25 (16)
C8—C1—C2—C70.97 (19)O3—S—C9—C10154.95 (15)
S—C1—C2—C7177.16 (13)O2—S—C9—C1024.22 (18)
C8—C1—C2—C3178.7 (2)C1—S—C9—C1091.01 (16)
S—C1—C2—C32.5 (3)O3—S—C9—C1426.26 (17)
C7—C2—C3—C40.6 (3)O2—S—C9—C14156.99 (14)
C1—C2—C3—C4179.76 (19)C1—S—C9—C1487.77 (16)
C2—C3—C4—C50.5 (3)C14—C9—C10—C111.5 (3)
C2—C3—C4—C15179.81 (18)S—C9—C10—C11177.28 (15)
C3—C4—C5—C60.7 (3)C9—C10—C11—C121.6 (3)
C15—C4—C5—C6179.93 (19)C10—C11—C12—C130.2 (3)
C4—C5—C6—C70.4 (3)C11—C12—C13—C141.3 (3)
C5—C6—C7—O1179.49 (16)C12—C13—C14—C91.4 (3)
C5—C6—C7—C21.6 (3)C10—C9—C14—C130.0 (3)
C8—O1—C7—C6179.09 (17)S—C9—C14—C13178.78 (14)
C8—O1—C7—C20.08 (19)C5—C4—C15—C16129.9 (2)
C3—C2—C7—C61.8 (3)C3—C4—C15—C1650.8 (3)
C1—C2—C7—C6178.49 (17)C5—C4—C15—C17104.7 (2)
C3—C2—C7—O1179.20 (15)C3—C4—C15—C1774.6 (3)
C1—C2—C7—O10.54 (19)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···Cg3i0.952.653.516 (3)152
C18—H18A···O20.982.393.119 (3)131
C10—H10···O20.952.582.938 (2)103
Symmetry code: (i) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC18H18O3S
Mr314.38
Crystal system, space groupMonoclinic, P21/c
Temperature (K)173
a, b, c (Å)10.736 (1), 13.024 (1), 11.729 (1)
β (°) 99.655 (2)
V3)1616.8 (2)
Z4
Radiation typeMo Kα
µ (mm1)0.21
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
9705, 3505, 3008
Rint0.066
(sin θ/λ)max1)0.639
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.049, 0.127, 0.98
No. of reflections3505
No. of parameters200
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.25, 0.53

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
C6—H6···Cg3i0.952.653.516 (3)151.9
C18—H18A···O20.982.393.119 (3)130.7
C10—H10···O20.952.582.938 (2)102.6
Symmetry code: (i) x+1, y+1, z+1.
 

References

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First citationChoi, H. D., Seo, P. J., Son, B. W. & Lee, U. (2008a). Acta Cryst. E64, o794.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationChoi, H. D., Seo, P. J., Son, B. W. & Lee, U. (2008b). Acta Cryst. E64, o850.  Web of Science CSD CrossRef IUCr Journals Google Scholar
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