5-Fluoro-3-(4-fluoro­phenyl­sulfin­yl)-2-methyl-1-benzofuran

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

doi:10.1107/S1600536810021823

organic compounds

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ISSN: 2056-9890

Volume 66| Part 7| July 2010| Page o1637

doi:10.1107/S1600536810021823

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5-Fluoro-3-(4-fluorophenylsulfinyl)-2-methyl-1-benzofuran

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

^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 5 June 2010; accepted 8 June 2010; online 16 June 2010)

In the title compound, C₁₅H₁₀F₂O₂S, the S=O and the 4-fluorophenyl groups are located on opposite sides of the plane of benzofuran ring system, and the 4-fluorophenyl ring is nearly perpendicular to the benzofuran plane with a dihedral angle of 89.93 (4)°. In the crystal structure, molecules are linked by weak intermolecular C—H⋯O hydrogen bonding and C—H⋯π interactions.

Related literature

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 ). For the structures of related 3-(4-fluorophenylsulfinyl)-2-methyl-1-benzofuran derivatives, see: Choi et al. (2010a ,b ).

Experimental

Crystal data

C₁₅H₁₀F₂O₂S
M_r = 292.29
Orthorhombic, P b c n
a = 14.9369 (4) Å
b = 10.6284 (3) Å
c = 16.1532 (4) Å
V = 2564.41 (12) Å³
Z = 8
Mo Kα radiation
μ = 0.27 mm⁻¹
T = 174 K
0.40 × 0.32 × 0.28 mm

Data collection

Bruker SMART APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.898, T_max = 0.927
22576 measured reflections
2962 independent reflections
2578 reflections with I > 2σ(I)
R_int = 0.029

Refinement

R[F² > 2σ(F²)] = 0.031
wR(F²) = 0.091
S = 1.08
2962 reflections
183 parameters
H-atom parameters constrained
Δρ_max = 0.29 e Å⁻³
Δρ_min = −0.32 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the furan ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C9—H9B⋯O2ⁱ	0.98	2.45	3.200 (2)	133
C14—H14⋯O2ⁱⁱ	0.95	2.55	3.270 (2)	133
C15—H15⋯Cgⁱⁱ	0.95	2.98	3.828 (2)	149
Symmetry codes: (i) $[-x+{\script{3\over 2}}, y-{\script{1\over 2}}, z]$ ; (ii) $[-x+{\script{3\over 2}}, y+{\script{1\over 2}}, z]$ .

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/S1600536810021823/xu2777sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810021823/xu2777Isup2.hkl

checkCIF report

Comment top

The compounds containing benzofuran skeleton exhibit diverse pharmacological properties such as antifungal (Aslam et al., 2006), antitumor and antiviral (Galal et al., 2009), antimicrobial (Khan et al., 2005) activities. These compounds widely occur 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-(4-fluorophenylsulfinyl)-2-methyl-1-benzofuran analogues (Choi et al., 2010a,b), 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 4-fluorophenyl ring is almost perpendicular to the plane of the benzofuran fragment [89.93 (4)°] and is tilted slightly towards it. The crystal packing (Fig. 2) is stabilized by weak intermolecular C–H···O hydrogen bonds; the first one between the methyl H atom and the oxygen of the S═O unit, with a C9–H9B···O2ⁱ, and the second one between the 4-fluorophenyl H atom and the oxygen of the S═O unit, with a C14–H14···O2ⁱⁱ, respectively (Table 1). The molecular packing (Fig. 2) is further stabilized by a C–H···π interaction between the 4-fluorophenyl H atom and the furan ring of an adjacent benzofuran system, with a C15–H15···Cg ⁱⁱ(Table 1; Cg is the centroid of the C1/C2/C7/O1/C8 furan ring).

Related literature top

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). For the crystal structures of related 3-(4-fluorophenylsulfinyl)-2-methyl-1-benzofuran derivatives, see: Choi et al. (2010a,b).

Experimental top

77% 3-Chloroperoxybenzoic acid (291 mg, 1.3 mmol) was added in small portions to a stirred solution of 5-fluoro-3-(4-fluorophenylsulfanyl)-2-methyl-1-benzofuran (350 mg, 1.2 mmol) in dichloromethane (30 ml) at 273 K. After being stirred at room temperature for 4 h, the mixture was washed with saturated sodium bicarbonate solution, 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 78%, m.p. 418-419 K; R_f = 0.49 (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 benzene 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 a 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 + 3/2, y - 1/2, z; (ii) - x +3/2, y + 1/2, z.]

5-Fluoro-3-(4-fluorophenylsulfinyl)-2-methyl-1-benzofuran top

Crystal data top

C₁₅H₁₀F₂O₂S	F(000) = 1200
M_r = 292.29	D_x = 1.514 Mg m⁻³
Orthorhombic, Pbcn	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2n 2ab	Cell parameters from 9962 reflections
a = 14.9369 (4) Å	θ = 2.4–27.6°
b = 10.6284 (3) Å	µ = 0.27 mm⁻¹
c = 16.1532 (4) Å	T = 174 K
V = 2564.41 (12) Å³	Block, colourless
Z = 8	0.40 × 0.32 × 0.28 mm

Data collection top

Bruker SMART APEXII CCD diffractometer	2962 independent reflections
Radiation source: rotating anode	2578 reflections with I > 2σ(I)
Graphite multilayer monochromator	R_int = 0.029
Detector resolution: 10.0 pixels mm^-1	θ_max = 27.6°, θ_min = 2.4°
ϕ and ω scans	h = −19→19
Absorption correction: multi-scan (SADABS; Bruker, 2009)	k = −13→11
T_min = 0.898, T_max = 0.927	l = −18→21
22576 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F² > 2σ(F²)] = 0.031	H-atom parameters constrained
wR(F²) = 0.091	w = 1/[σ²(F_o²) + (0.0448P)² + 0.984P] where P = (F_o² + 2F_c²)/3
S = 1.08	(Δ/σ)_max < 0.001
2962 reflections	Δρ_max = 0.29 e Å⁻³
183 parameters	Δρ_min = −0.32 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0035 (5)

Crystal data top

C₁₅H₁₀F₂O₂S	V = 2564.41 (12) Å³
M_r = 292.29	Z = 8
Orthorhombic, Pbcn	Mo Kα radiation
a = 14.9369 (4) Å	µ = 0.27 mm⁻¹
b = 10.6284 (3) Å	T = 174 K
c = 16.1532 (4) Å	0.40 × 0.32 × 0.28 mm

Data collection top

Bruker SMART APEXII CCD diffractometer	2962 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	2578 reflections with I > 2σ(I)
T_min = 0.898, T_max = 0.927	R_int = 0.029
22576 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.031	0 restraints
wR(F²) = 0.091	H-atom parameters constrained
S = 1.08	Δρ_max = 0.29 e Å⁻³
2962 reflections	Δρ_min = −0.32 e Å⁻³
183 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 > 2sigma(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

	x	y	z	U_iso*/U_eq
S1	0.66618 (2)	0.39412 (3)	0.07071 (2)	0.02868 (12)
F1	0.74089 (8)	0.39246 (10)	0.42659 (5)	0.0468 (3)
F2	0.43716 (7)	0.81769 (9)	0.16672 (7)	0.0533 (3)
O1	0.59409 (7)	0.09156 (9)	0.19275 (6)	0.0308 (2)
O2	0.76049 (7)	0.43398 (11)	0.08603 (7)	0.0371 (3)
C1	0.63924 (9)	0.27918 (12)	0.14445 (8)	0.0257 (3)
C2	0.65824 (8)	0.27675 (12)	0.23194 (8)	0.0244 (3)
C3	0.69806 (9)	0.35842 (13)	0.28866 (9)	0.0287 (3)
H3	0.7198	0.4390	0.2730	0.034*
C4	0.70389 (10)	0.31507 (14)	0.36869 (9)	0.0317 (3)
C5	0.67501 (10)	0.19769 (15)	0.39509 (9)	0.0334 (3)
H5	0.6817	0.1735	0.4514	0.040*
C6	0.63635 (10)	0.11614 (13)	0.33859 (9)	0.0318 (3)
H6	0.6159	0.0350	0.3544	0.038*
C7	0.62909 (8)	0.15881 (12)	0.25823 (8)	0.0265 (3)
C8	0.60257 (9)	0.16619 (13)	0.12435 (9)	0.0287 (3)
C9	0.57225 (10)	0.11157 (15)	0.04501 (10)	0.0379 (4)
H9A	0.5068	0.1058	0.0448	0.057*
H9B	0.5979	0.0273	0.0384	0.057*
H9C	0.5919	0.1654	−0.0008	0.057*
C10	0.59618 (9)	0.51953 (13)	0.10727 (8)	0.0275 (3)
C11	0.50426 (10)	0.50221 (15)	0.11532 (10)	0.0354 (3)
H11	0.4786	0.4215	0.1066	0.043*
C12	0.45059 (10)	0.60330 (15)	0.13609 (11)	0.0401 (4)
H12	0.3877	0.5934	0.1423	0.048*
C13	0.49058 (11)	0.71859 (14)	0.14756 (10)	0.0364 (3)
C14	0.58090 (11)	0.73846 (14)	0.13999 (10)	0.0391 (4)
H14	0.6061	0.8195	0.1488	0.047*
C15	0.63445 (10)	0.63648 (14)	0.11909 (9)	0.0342 (3)
H15	0.6972	0.6471	0.1129	0.041*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.03005 (19)	0.0329 (2)	0.02308 (18)	0.00313 (13)	−0.00015 (12)	0.00211 (12)
F1	0.0588 (6)	0.0527 (6)	0.0289 (5)	−0.0174 (5)	−0.0098 (4)	−0.0059 (4)
F2	0.0614 (6)	0.0369 (5)	0.0617 (7)	0.0204 (5)	0.0077 (5)	0.0049 (5)
O1	0.0328 (5)	0.0259 (5)	0.0338 (5)	−0.0047 (4)	−0.0004 (4)	−0.0046 (4)
O2	0.0271 (5)	0.0422 (6)	0.0421 (6)	0.0011 (4)	0.0044 (4)	0.0098 (5)
C1	0.0250 (6)	0.0265 (6)	0.0257 (6)	0.0018 (5)	−0.0009 (5)	−0.0013 (5)
C2	0.0227 (6)	0.0250 (6)	0.0256 (6)	0.0021 (5)	0.0002 (5)	−0.0009 (5)
C3	0.0305 (7)	0.0261 (6)	0.0294 (7)	−0.0034 (5)	−0.0007 (5)	−0.0014 (5)
C4	0.0312 (7)	0.0363 (7)	0.0275 (7)	−0.0027 (6)	−0.0048 (5)	−0.0038 (6)
C5	0.0342 (7)	0.0388 (8)	0.0273 (7)	0.0008 (6)	−0.0016 (6)	0.0063 (6)
C6	0.0331 (7)	0.0272 (7)	0.0352 (8)	−0.0009 (5)	0.0024 (6)	0.0053 (6)
C7	0.0248 (6)	0.0244 (6)	0.0302 (7)	0.0002 (5)	−0.0003 (5)	−0.0031 (5)
C8	0.0256 (6)	0.0302 (7)	0.0302 (7)	0.0024 (5)	−0.0005 (5)	−0.0039 (5)
C9	0.0349 (8)	0.0414 (8)	0.0373 (8)	−0.0003 (6)	−0.0064 (6)	−0.0134 (6)
C10	0.0292 (6)	0.0289 (7)	0.0244 (6)	0.0016 (5)	−0.0027 (5)	0.0035 (5)
C11	0.0285 (6)	0.0306 (7)	0.0471 (9)	−0.0018 (6)	−0.0034 (6)	0.0011 (6)
C12	0.0295 (7)	0.0414 (9)	0.0493 (10)	0.0042 (6)	−0.0001 (7)	0.0055 (7)
C13	0.0435 (8)	0.0303 (7)	0.0352 (8)	0.0101 (6)	0.0008 (6)	0.0064 (6)
C14	0.0477 (9)	0.0267 (7)	0.0429 (9)	−0.0032 (6)	0.0018 (7)	0.0028 (6)
C15	0.0318 (7)	0.0334 (7)	0.0374 (8)	−0.0051 (6)	0.0005 (6)	0.0041 (6)

Geometric parameters (Å, º) top

S1—O2	1.492 (1)	C6—C7	1.379 (2)
S1—C1	1.753 (1)	C6—H6	0.9500
S1—C10	1.794 (1)	C8—C9	1.478 (2)
F1—C4	1.363 (2)	C9—H9A	0.9800
F2—C13	1.357 (2)	C9—H9B	0.9800
O1—C8	1.366 (2)	C9—H9C	0.9800
O1—C7	1.379 (2)	C10—C15	1.381 (2)
C1—C8	1.359 (2)	C10—C11	1.391 (2)
C1—C2	1.442 (2)	C11—C12	1.382 (2)
C2—C7	1.393 (2)	C11—H11	0.9500
C2—C3	1.395 (2)	C12—C13	1.376 (2)
C3—C4	1.375 (2)	C12—H12	0.9500
C3—H3	0.9500	C13—C14	1.371 (2)
C4—C5	1.387 (2)	C14—C15	1.389 (2)
C5—C6	1.385 (2)	C14—H14	0.9500
C5—H5	0.9500	C15—H15	0.9500

O2—S1—C1	107.57 (6)	C1—C8—C9	132.66 (14)
O2—S1—C10	106.55 (7)	O1—C8—C9	116.41 (13)
C1—S1—C10	99.22 (6)	C8—C9—H9A	109.5
C8—O1—C7	106.51 (10)	C8—C9—H9B	109.5
C8—C1—C2	107.32 (12)	H9A—C9—H9B	109.5
C8—C1—S1	123.09 (10)	C8—C9—H9C	109.5
C2—C1—S1	129.30 (10)	H9A—C9—H9C	109.5
C7—C2—C3	119.53 (12)	H9B—C9—H9C	109.5
C7—C2—C1	104.67 (11)	C15—C10—C11	120.97 (13)
C3—C2—C1	135.77 (13)	C15—C10—S1	118.22 (11)
C4—C3—C2	115.84 (13)	C11—C10—S1	120.50 (11)
C4—C3—H3	122.1	C12—C11—C10	119.48 (14)
C2—C3—H3	122.1	C12—C11—H11	120.3
F1—C4—C3	117.95 (13)	C10—C11—H11	120.3
F1—C4—C5	117.26 (13)	C13—C12—C11	118.25 (14)
C3—C4—C5	124.79 (13)	C13—C12—H12	120.9
C6—C5—C4	119.34 (13)	C11—C12—H12	120.9
C6—C5—H5	120.3	F2—C13—C14	118.64 (14)
C4—C5—H5	120.3	F2—C13—C12	117.82 (14)
C7—C6—C5	116.56 (13)	C14—C13—C12	123.53 (14)
C7—C6—H6	121.7	C13—C14—C15	117.92 (14)
C5—C6—H6	121.7	C13—C14—H14	121.0
C6—C7—O1	125.52 (12)	C15—C14—H14	121.0
C6—C7—C2	123.92 (13)	C10—C15—C14	119.84 (14)
O1—C7—C2	110.55 (12)	C10—C15—H15	120.1
C1—C8—O1	110.93 (12)	C14—C15—H15	120.1

O2—S1—C1—C8	−129.33 (12)	C1—C2—C7—O1	−0.14 (14)
C10—S1—C1—C8	119.93 (12)	C2—C1—C8—O1	1.61 (15)
O2—S1—C1—C2	43.56 (14)	S1—C1—C8—O1	175.85 (9)
C10—S1—C1—C2	−67.18 (13)	C2—C1—C8—C9	−177.80 (14)
C8—C1—C2—C7	−0.87 (14)	S1—C1—C8—C9	−3.6 (2)
S1—C1—C2—C7	−174.64 (10)	C7—O1—C8—C1	−1.69 (15)
C8—C1—C2—C3	176.94 (15)	C7—O1—C8—C9	177.83 (12)
S1—C1—C2—C3	3.2 (2)	O2—S1—C10—C15	17.87 (13)
C7—C2—C3—C4	−1.17 (19)	C1—S1—C10—C15	129.42 (12)
C1—C2—C3—C4	−178.74 (14)	O2—S1—C10—C11	−168.52 (11)
C2—C3—C4—F1	−178.89 (12)	C1—S1—C10—C11	−56.97 (13)
C2—C3—C4—C5	1.3 (2)	C15—C10—C11—C12	−0.5 (2)
F1—C4—C5—C6	179.52 (13)	S1—C10—C11—C12	−173.95 (12)
C3—C4—C5—C6	−0.7 (2)	C10—C11—C12—C13	0.4 (2)
C4—C5—C6—C7	−0.1 (2)	C11—C12—C13—F2	179.03 (14)
C5—C6—C7—O1	178.89 (12)	C11—C12—C13—C14	−0.4 (3)
C5—C6—C7—C2	0.2 (2)	F2—C13—C14—C15	−179.02 (14)
C8—O1—C7—C6	−177.78 (13)	C12—C13—C14—C15	0.4 (2)
C8—O1—C7—C2	1.10 (14)	C11—C10—C15—C14	0.5 (2)
C3—C2—C7—C6	0.5 (2)	S1—C10—C15—C14	174.11 (12)
C1—C2—C7—C6	178.75 (13)	C13—C14—C15—C10	−0.5 (2)
C3—C2—C7—O1	−178.39 (11)

Hydrogen-bond geometry (Å, º) top

Cg is the centroid of the furan ring.

D—H···A	D—H	H···A	D···A	D—H···A
C9—H9B···O2ⁱ	0.98	2.45	3.200 (2)	133
C14—H14···O2ⁱⁱ	0.95	2.55	3.270 (2)	133
C15—H15···Cgⁱⁱ	0.95	2.98	3.828 (2)	149

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

Experimental details

Crystal data
Chemical formula	C₁₅H₁₀F₂O₂S
M_r	292.29
Crystal system, space group	Orthorhombic, Pbcn
Temperature (K)	174
a, b, c (Å)	14.9369 (4), 10.6284 (3), 16.1532 (4)
V (Å³)	2564.41 (12)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.27
Crystal size (mm)	0.40 × 0.32 × 0.28

Data collection
Diffractometer	Bruker SMART APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.898, 0.927
No. of measured, independent and observed [I > 2σ(I)] reflections	22576, 2962, 2578
R_int	0.029
(sin θ/λ)_max (Å⁻¹)	0.651

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.031, 0.091, 1.08
No. of reflections	2962
No. of parameters	183
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.29, −0.32

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 furan ring.

D—H···A	D—H	H···A	D···A	D—H···A
C9—H9B···O2ⁱ	0.98	2.45	3.200 (2)	132.7
C14—H14···O2ⁱⁱ	0.95	2.55	3.270 (2)	133.1
C15—H15···Cgⁱⁱ	0.95	2.98	3.828 (2)	148.9

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

Acknowledgements

This work was supported by a Dong-eui University grant (2010AA096).

References

Akgul, Y. Y. & Anil, H. (2003). Phytochemistry, 63, 939–943. Web of Science CrossRef PubMed CAS Google Scholar
Aslam, S. N., Stevenson, P. C., Phythian, S. J., Veitch, N. C. & Hall, D. R. (2006). Tetrahedron, 62, 4214–4226. Web of Science CrossRef CAS Google Scholar
Brandenburg, K. (1998). DIAMOND. Crystal Impact GbR, Bonn, Germany. Google Scholar
Bruker (2009). APEX2. SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Choi, H. D., Seo, P. J., Son, B. W. & Lee, U. (2010a). Acta Cryst. E66, o543. Web of Science CSD CrossRef IUCr Journals Google Scholar
Choi, H. D., Seo, P. J., Son, B. W. & Lee, U. (2010b). Acta Cryst. E66, o1297. Web of Science CSD CrossRef IUCr Journals Google Scholar
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Galal, S. A., Abd El-All, A. S., Abdallah, M. M. & El-Diwani, H. I. (2009). Bioorg. Med. Chem. Lett. 19, 2420–2428. Web of Science CrossRef PubMed CAS Google Scholar
Khan, M. W., Alam, M. J., Rashid, M. A. & Chowdhury, R. (2005). Bioorg. Med. Chem. 13, 4796–4805. Web of Science CrossRef PubMed CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Soekamto, N. H., Achmad, S. A., Ghisalberti, E. L., Hakim, E. H. & Syah, Y. M. (2003). Phytochemistry, 64, 831–834. Web of Science CrossRef PubMed CAS Google Scholar

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Volume 66| Part 7| July 2010| Page o1637

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