2-(4-Chloro­phen­yl)-3-ethyl­sulfinyl-5-fluoro-1-benzofuran

Choi, H.D.; Seo, P.J.; Son, B.W.; Lee, U.

doi:10.1107/S1600536810008172

organic compounds

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ISSN: 2056-9890

Volume 66| Part 4| April 2010| Page o770

doi:10.1107/S1600536810008172

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2-(4-Chlorophenyl)-3-ethylsulfinyl-5-fluoro-1-benzofuran

Hong Dae Choi,^a Pil Ja Seo,^a Byeng Wha Son ^a and Uk Lee ^a ^*

^aDepartment of Chemistry, Dongeui University, San 24 Kaya-dong Busanjin-gu, Busan 614-714, Republic of Korea
^*Correspondence e-mail: uklee@pknu.ac.kr

(Received 22 February 2010; accepted 3 March 2010; online 6 March 2010)

In the title compound, C₁₆H₁₂ClFO₂S, the 4-chlorophenyl ring is rotated out of the benzofuran plane, as indicated by the dihedral angle of 19.79 (8)°. The crystal structure exhibits weak intermolecular C—H⋯O hydrogen bonds and C—H⋯π interactions.

Related literature

For the crystal structures of similar 3-ethylsulfinyl-2-(4-fluorophenyl)-5-halo-1-benzofuran derivatives, see: Choi et al. (2010a ,b ,c ). For the pharmacological activity of benzofuran compounds, see: Aslam et al. (2006 ); Galal et al. (2009 ); Khan et al. (2005 ). For natural products with benzofuran rings, see: Akgul & Anil (2003 ); Soekamto et al. (2003 ).

Experimental

Crystal data

C₁₆H₁₂ClFO₂S
M_r = 322.77
Monoclinic, P 2₁ /c
a = 11.5257 (9) Å
b = 7.9655 (6) Å
c = 16.395 (1) Å
β = 106.518 (1)°
V = 1443.07 (18) Å³
Z = 4
Mo Kα radiation
μ = 0.42 mm⁻¹
T = 173 K
0.40 × 0.35 × 0.35 mm

Data collection

Bruker SMART APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.850, T_max = 0.867
12345 measured reflections
3290 independent reflections
2713 reflections with I > 2σ(I)
R_int = 0.028

Refinement

R[F² > 2σ(F²)] = 0.034
wR(F²) = 0.085
S = 1.05
3290 reflections
191 parameters
H-atom parameters constrained
Δρ_max = 0.29 e Å⁻³
Δρ_min = −0.27 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C9–C14 4-chlorophenyl ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C6—H6⋯O2ⁱ	0.93	2.52	3.371 (2)	152
C11—H11⋯O2ⁱⁱ	0.93	2.53	3.116 (2)	121
C15—H15A⋯Cgⁱⁱ	0.97	2.66	3.560 (2)	155
Symmetry codes: (i) $[x, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]$ ; (ii) $[-x+1, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; 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.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810008172/bh2275sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810008172/bh2275Isup2.hkl

checkCIF report

Comment top

Compounds containing benzofuran moiety show diverse pharmacological activities such as antifungal (Aslam et al., 2006), antitumor and antiviral (Galal et al., 2009), antimicrobial (Khan et al., 2005) properties. These compounds are widely occurring in nature (Akgul & Anil, 2003; Soekamto et al., 2003). As a part of our ongoing studies of the effect of side chain substituents on the solid state structures of 3-ethylsulfinyl-2-(4-fluorophenyl)-5-halo-1-benzofuran analogues (Choi et al., 2010a,b,c), we report the crystal structure of the title compound (Fig. 1).

The benzofuran unit is essentially planar, with a mean deviation of 0.012 (1) Å from the least-squares plane defined by the nine constituent atoms. The dihedral angle formed by the benzofuran plane and the 4-fluorophenyl ring is 19.79 (8)°. The crystal packing (Fig. 2) is stabilized by two different C—H···O hydrogen bonds; the first between the benzene H atom and the oxygen of the S═O unit, with a C6—H6···O2ⁱ, and the second between the 4-chlorophenyl H atom and the oxygen of the S═O unit, with a C11—H11···O2ⁱⁱ, respectively (Table 1). The crystal packing (Fig. 2) is further stabilized by a C—H···π interaction between the methylene H atom and the 4-chlorophenyl ring, with a C15—H15A···Cgⁱⁱ (Table 1; Cg is the centroid of the C9–C14 4-chlorophenyl ring).

Related literature top

For the crystal structures of similar 3-ethylsulfinyl-2-(4-fluorophenyl)-5-halo-1-benzofuran derivatives, see: Choi et al. (2010a,b,c). For the pharmacological activity of benzofuran compounds, see: Aslam et al. (2006); Galal et al. (2009); Khan et al. (2005). For natural products with benzofuran rings, see: Akgul & Anil (2003); Soekamto et al. (2003).

Experimental top

77% 3-Chloroperoxybenzoic acid (291 mg, 1.3 mmol) was added in small portions to a stirred solution of 2-(4-chlorophenyl)-3-ethylsulfanyl-5-fluoro-1-benzofuran (368 mg, 1.2 mmol) in dichloromethane (30 mL) at 273 K. After being stirred at room temperature for 4h, the mixture was washed with saturated sodium bicarbonate solution and the organic layer was separated, dried over magnesium sulfate, filtered and concentrated at reduced pressure. The residue was purified by column chromatography (hexane–ethyl acetate, 1:1 v/v) to afford the title compound as a colorless solid [yield 79%, m.p. 405–406 K; R_f = 0.64 (hexane–ethyl acetate, 1:1 v/v)]. Single crystals suitable for X-ray diffraction were prepared by slow evaporation of a solution of the title compound in acetone at room temperature.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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

	Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 50 % probability level. H atoms are presented as small spheres of arbitrary radius.
	Fig. 2. C—H···O and C—H···π interactions (dotted lines) in the crystal structure of the title compound. Cg denotes the ring centroid. [Symmetry codes: (i) x, - y + 3/2, z - 1/2; (ii) - x + 1, y - 1/2, - z + 3/2; (iii) x, - y + 3/2, z + 1/2; (iv) - x + 1, y + 1/2, - z + 3/2.]

2-(4-Chlorophenyl)-3-ethylsulfinyl-5-fluoro-1-benzofuran top

Crystal data top

C₁₆H₁₂ClFO₂S	F(000) = 664
M_r = 322.77	D_x = 1.486 Mg m⁻³
Monoclinic, P2₁/c	Melting point = 405–406 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 11.5257 (9) Å	Cell parameters from 5508 reflections
b = 7.9655 (6) Å	θ = 2.6–27.4°
c = 16.395 (1) Å	µ = 0.42 mm⁻¹
β = 106.518 (1)°	T = 173 K
V = 1443.07 (18) Å³	Block, colourless
Z = 4	0.40 × 0.35 × 0.35 mm

Data collection top

Bruker SMART APEXII CCD diffractometer	3290 independent reflections
Radiation source: Rotating Anode	2713 reflections with I > 2σ(I)
Bruker HELIOS graded multilayer optics monochromator	R_int = 0.028
Detector resolution: 10.0 pixels mm^-1	θ_max = 27.5°, θ_min = 1.8°
ϕ and ω scans	h = −14→14
Absorption correction: multi-scan (SADABS; Bruker, 2009)	k = −10→10
T_min = 0.850, T_max = 0.867	l = −21→20
12345 measured reflections

Refinement top

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)] = 0.034	Hydrogen site location: difference Fourier map
wR(F²) = 0.085	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0338P)² + 0.7418P] where P = (F_o² + 2F_c²)/3
3290 reflections	(Δ/σ)_max < 0.001
191 parameters	Δρ_max = 0.29 e Å⁻³
0 restraints	Δρ_min = −0.27 e Å⁻³
0 constraints

Crystal data top

C₁₆H₁₂ClFO₂S	V = 1443.07 (18) Å³
M_r = 322.77	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 11.5257 (9) Å	µ = 0.42 mm⁻¹
b = 7.9655 (6) Å	T = 173 K
c = 16.395 (1) Å	0.40 × 0.35 × 0.35 mm
β = 106.518 (1)°

Data collection top

Bruker SMART APEXII CCD diffractometer	3290 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	2713 reflections with I > 2σ(I)
T_min = 0.850, T_max = 0.867	R_int = 0.028
12345 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.034	0 restraints
wR(F²) = 0.085	H-atom parameters constrained
S = 1.05	Δρ_max = 0.29 e Å⁻³
3290 reflections	Δρ_min = −0.27 e Å⁻³
191 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Cl	1.01429 (4)	0.47181 (6)	0.72194 (3)	0.03651 (13)
S	0.37916 (4)	0.44605 (5)	0.71678 (2)	0.02292 (11)
F	−0.02836 (9)	0.79231 (16)	0.49298 (7)	0.0447 (3)
O1	0.45081 (10)	0.71492 (14)	0.53223 (7)	0.0262 (3)
O2	0.30653 (12)	0.54333 (16)	0.76279 (8)	0.0335 (3)
C1	0.38345 (15)	0.56819 (19)	0.62737 (10)	0.0228 (3)
C2	0.28142 (15)	0.6562 (2)	0.57188 (10)	0.0242 (3)
C3	0.15813 (15)	0.6723 (2)	0.56551 (11)	0.0282 (4)
H3	0.1231	0.6178	0.6028	0.034*
C4	0.09200 (16)	0.7732 (2)	0.50110 (12)	0.0321 (4)
C5	0.13881 (17)	0.8572 (2)	0.44327 (11)	0.0328 (4)
H5	0.0886	0.9230	0.4008	0.039*
C6	0.26012 (17)	0.8427 (2)	0.44906 (11)	0.0292 (4)
H6	0.2942	0.8969	0.4112	0.035*
C7	0.32842 (15)	0.7429 (2)	0.51444 (10)	0.0249 (3)
C8	0.48285 (15)	0.6093 (2)	0.60191 (10)	0.0233 (3)
C9	0.61217 (15)	0.5719 (2)	0.63190 (10)	0.0236 (3)
C10	0.65770 (15)	0.4350 (2)	0.68435 (11)	0.0262 (4)
H10	0.6045	0.3628	0.7002	0.031*
C11	0.78105 (15)	0.4052 (2)	0.71314 (11)	0.0274 (4)
H11	0.8108	0.3149	0.7489	0.033*
C12	0.85925 (15)	0.5115 (2)	0.68801 (11)	0.0270 (4)
C13	0.81697 (16)	0.6470 (2)	0.63528 (11)	0.0308 (4)
H13	0.8706	0.7166	0.6183	0.037*
C14	0.69410 (16)	0.6776 (2)	0.60811 (11)	0.0288 (4)
H14	0.6653	0.7698	0.5735	0.035*
C15	0.28229 (16)	0.2801 (2)	0.66061 (11)	0.0285 (4)
H15A	0.2502	0.2179	0.7002	0.034*
H15B	0.2146	0.3287	0.6177	0.034*
C16	0.3499 (2)	0.1613 (2)	0.61849 (13)	0.0414 (5)
H16A	0.3808	0.2223	0.5786	0.062*
H16B	0.2959	0.0750	0.5891	0.062*
H16C	0.4159	0.1113	0.6610	0.062*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl	0.0231 (2)	0.0483 (3)	0.0378 (3)	0.00038 (19)	0.00815 (18)	−0.0005 (2)
S	0.0255 (2)	0.0234 (2)	0.0200 (2)	0.00029 (16)	0.00665 (15)	0.00033 (15)
F	0.0275 (6)	0.0575 (8)	0.0458 (7)	0.0124 (5)	0.0052 (5)	0.0073 (6)
O1	0.0286 (6)	0.0259 (6)	0.0249 (6)	0.0006 (5)	0.0091 (5)	0.0030 (5)
O2	0.0433 (8)	0.0313 (7)	0.0311 (7)	0.0041 (6)	0.0192 (6)	−0.0023 (5)
C1	0.0251 (8)	0.0207 (8)	0.0223 (8)	0.0015 (6)	0.0065 (6)	0.0010 (6)
C2	0.0293 (9)	0.0213 (8)	0.0218 (8)	0.0021 (7)	0.0072 (7)	−0.0013 (6)
C3	0.0279 (9)	0.0302 (9)	0.0269 (9)	0.0025 (7)	0.0085 (7)	0.0007 (7)
C4	0.0275 (9)	0.0348 (10)	0.0315 (9)	0.0059 (8)	0.0043 (7)	−0.0031 (8)
C5	0.0400 (11)	0.0291 (9)	0.0246 (9)	0.0081 (8)	0.0017 (8)	0.0012 (7)
C6	0.0407 (10)	0.0249 (9)	0.0218 (8)	0.0019 (7)	0.0086 (7)	0.0001 (7)
C7	0.0284 (9)	0.0226 (8)	0.0240 (8)	0.0017 (7)	0.0077 (7)	−0.0024 (6)
C8	0.0292 (9)	0.0191 (8)	0.0218 (8)	−0.0012 (7)	0.0077 (7)	−0.0008 (6)
C9	0.0254 (8)	0.0234 (8)	0.0227 (8)	−0.0014 (6)	0.0080 (7)	−0.0040 (6)
C10	0.0264 (9)	0.0224 (8)	0.0322 (9)	−0.0027 (7)	0.0123 (7)	−0.0007 (7)
C11	0.0290 (9)	0.0233 (8)	0.0300 (9)	0.0030 (7)	0.0086 (7)	0.0006 (7)
C12	0.0221 (8)	0.0329 (9)	0.0260 (8)	−0.0008 (7)	0.0070 (7)	−0.0068 (7)
C13	0.0303 (9)	0.0343 (10)	0.0298 (9)	−0.0074 (8)	0.0115 (8)	0.0017 (8)
C14	0.0313 (9)	0.0293 (9)	0.0258 (9)	−0.0029 (7)	0.0082 (7)	0.0037 (7)
C15	0.0308 (9)	0.0234 (8)	0.0286 (9)	−0.0050 (7)	0.0038 (7)	0.0005 (7)
C16	0.0585 (13)	0.0296 (10)	0.0344 (11)	0.0016 (9)	0.0105 (9)	−0.0066 (8)

Geometric parameters (Å, º) top

Cl—C12	1.7427 (17)	C8—C9	1.461 (2)
S—O2	1.4930 (12)	C9—C10	1.395 (2)
S—C1	1.7717 (16)	C9—C14	1.401 (2)
S—C15	1.8047 (17)	C10—C11	1.385 (2)
F—C4	1.364 (2)	C10—H10	0.9300
O1—C7	1.375 (2)	C11—C12	1.382 (2)
O1—C8	1.3820 (19)	C11—H11	0.9300
C1—C8	1.366 (2)	C12—C13	1.382 (2)
C1—C2	1.447 (2)	C13—C14	1.380 (2)
C2—C7	1.395 (2)	C13—H13	0.9300
C2—C3	1.401 (2)	C14—H14	0.9300
C3—C4	1.373 (2)	C15—C16	1.512 (3)
C3—H3	0.9300	C15—H15A	0.9700
C4—C5	1.389 (3)	C15—H15B	0.9700
C5—C6	1.379 (3)	C16—H16A	0.9600
C5—H5	0.9300	C16—H16B	0.9600
C6—C7	1.386 (2)	C16—H16C	0.9600
C6—H6	0.9300

O2—S—C1	106.53 (7)	C10—C9—C8	122.36 (15)
O2—S—C15	106.47 (8)	C14—C9—C8	119.21 (15)
C1—S—C15	97.97 (8)	C11—C10—C9	120.90 (16)
C7—O1—C8	106.91 (12)	C11—C10—H10	119.5
C8—C1—C2	107.11 (14)	C9—C10—H10	119.5
C8—C1—S	127.41 (13)	C12—C11—C10	119.14 (16)
C2—C1—S	125.26 (12)	C12—C11—H11	120.4
C7—C2—C3	118.97 (15)	C10—C11—H11	120.4
C7—C2—C1	105.19 (14)	C11—C12—C13	121.38 (16)
C3—C2—C1	135.83 (16)	C11—C12—Cl	119.38 (14)
C4—C3—C2	116.15 (16)	C13—C12—Cl	119.23 (14)
C4—C3—H3	121.9	C14—C13—C12	119.14 (16)
C2—C3—H3	121.9	C14—C13—H13	120.4
F—C4—C3	117.85 (16)	C12—C13—H13	120.4
F—C4—C5	117.48 (16)	C13—C14—C9	121.00 (16)
C3—C4—C5	124.67 (17)	C13—C14—H14	119.5
C6—C5—C4	119.71 (16)	C9—C14—H14	119.5
C6—C5—H5	120.1	C16—C15—S	111.53 (13)
C4—C5—H5	120.1	C16—C15—H15A	109.3
C5—C6—C7	116.30 (16)	S—C15—H15A	109.3
C5—C6—H6	121.8	C16—C15—H15B	109.3
C7—C6—H6	121.8	S—C15—H15B	109.3
O1—C7—C6	125.43 (15)	H15A—C15—H15B	108.0
O1—C7—C2	110.38 (14)	C15—C16—H16A	109.5
C6—C7—C2	124.18 (16)	C15—C16—H16B	109.5
C1—C8—O1	110.38 (14)	H16A—C16—H16B	109.5
C1—C8—C9	135.43 (15)	C15—C16—H16C	109.5
O1—C8—C9	114.16 (14)	H16A—C16—H16C	109.5
C10—C9—C14	118.43 (16)	H16B—C16—H16C	109.5

O2—S—C1—C8	130.71 (15)	C2—C1—C8—O1	−1.44 (18)
C15—S—C1—C8	−119.40 (16)	S—C1—C8—O1	−176.28 (11)
O2—S—C1—C2	−43.25 (16)	C2—C1—C8—C9	176.59 (17)
C15—S—C1—C2	66.64 (15)	S—C1—C8—C9	1.8 (3)
C8—C1—C2—C7	1.33 (18)	C7—O1—C8—C1	0.97 (17)
S—C1—C2—C7	176.32 (12)	C7—O1—C8—C9	−177.52 (13)
C8—C1—C2—C3	−177.60 (19)	C1—C8—C9—C10	20.4 (3)
S—C1—C2—C3	−2.6 (3)	O1—C8—C9—C10	−161.65 (14)
C7—C2—C3—C4	0.7 (2)	C1—C8—C9—C14	−158.99 (19)
C1—C2—C3—C4	179.52 (18)	O1—C8—C9—C14	19.0 (2)
C2—C3—C4—F	−179.86 (15)	C14—C9—C10—C11	0.8 (2)
C2—C3—C4—C5	0.3 (3)	C8—C9—C10—C11	−178.60 (15)
F—C4—C5—C6	179.66 (16)	C9—C10—C11—C12	−1.2 (3)
C3—C4—C5—C6	−0.5 (3)	C10—C11—C12—C13	0.4 (3)
C4—C5—C6—C7	−0.3 (3)	C10—C11—C12—Cl	−178.48 (13)
C8—O1—C7—C6	179.89 (16)	C11—C12—C13—C14	0.8 (3)
C8—O1—C7—C2	−0.08 (17)	Cl—C12—C13—C14	179.64 (14)
C5—C6—C7—O1	−178.60 (15)	C12—C13—C14—C9	−1.2 (3)
C5—C6—C7—C2	1.4 (3)	C10—C9—C14—C13	0.4 (3)
C3—C2—C7—O1	178.38 (14)	C8—C9—C14—C13	179.81 (16)
C1—C2—C7—O1	−0.77 (18)	O2—S—C15—C16	−174.17 (12)
C3—C2—C7—C6	−1.6 (3)	C1—S—C15—C16	75.90 (14)
C1—C2—C7—C6	179.26 (15)

Hydrogen-bond geometry (Å, º) top

Cg is the centroid of the C9–C14 4-chlorophenyl ring.

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···O2ⁱ	0.93	2.52	3.371 (2)	152
C11—H11···O2ⁱⁱ	0.93	2.53	3.116 (2)	121
C15—H15A···Cgⁱⁱ	0.97	2.66	3.560 (2)	155

Symmetry codes: (i) x, −y+3/2, z−1/2; (ii) −x+1, y−1/2, −z+3/2.

Experimental details

Crystal data
Chemical formula	C₁₆H₁₂ClFO₂S
M_r	322.77
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	173
a, b, c (Å)	11.5257 (9), 7.9655 (6), 16.395 (1)
β (°)	106.518 (1)
V (Å³)	1443.07 (18)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.42
Crystal size (mm)	0.40 × 0.35 × 0.35

Data collection
Diffractometer	Bruker SMART APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.850, 0.867
No. of measured, independent and observed [I > 2σ(I)] reflections	12345, 3290, 2713
R_int	0.028
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.034, 0.085, 1.05
No. of reflections	3290
No. of parameters	191
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.29, −0.27

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1998).

Hydrogen-bond geometry (Å, º) top

Cg is the centroid of the C9–C14 4-chlorophenyl ring.

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···O2ⁱ	0.93	2.52	3.371 (2)	151.9
C11—H11···O2ⁱⁱ	0.93	2.53	3.116 (2)	121.3
C15—H15A···Cgⁱⁱ	0.97	2.66	3.560 (2)	155.4

Symmetry codes: (i) x, −y+3/2, z−1/2; (ii) −x+1, y−1/2, −z+3/2.

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Volume 66| Part 4| April 2010| Page o770

doi:10.1107/S1600536810008172

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