3-(4-Fluoro­phenyl­sulfin­yl)-5-iodo-2-methyl-1-benzofuran

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

doi:10.1107/S1600536810024931

organic compounds

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ISSN: 2056-9890

Volume 66| Part 7| July 2010| Page o1876

doi:10.1107/S1600536810024931

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3-(4-Fluorophenylsulfinyl)-5-iodo-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 10 May 2010; accepted 25 June 2010; online 30 June 2010)

In the title compound, C₁₅H₁₀FIO₂S, the O atom and the 4-fluorophenyl group of the 4-fluorophenylsulfinyl substituent are located on opposite sides of the plane through the benzofuran fragment; the 4-fluorophenyl ring is nearly perpendicular to this plane, making a dihedral angle of 83.37 (7)°. The crystal structure is stabilized by weak intermolecular C—H⋯O hydrogen bonds and an I⋯O interaction [I⋯O = 3.255 (2) Å]. The crystal structure also exhibits intermolecular C—F⋯π interactions [3.068 (2) Å], and aromatic π–π interactions between the furan and benzene rings of neighbouring benzofuran fragments [centroid–centroid distance = 3.636 (2) Å].

Related literature

For the crystal structures of similar 3-(4-fluorophenylsulfinyl)-2-methyl-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 ). For a review of halogen bonding, see: Politzer et al. (2007 ).

Experimental

Crystal data

C₁₅H₁₀FIO₂S
M_r = 400.19
Monoclinic, P 2₁ /c
a = 13.1665 (4) Å
b = 11.4338 (4) Å
c = 9.9296 (3) Å
β = 107.181 (1)°
V = 1428.13 (8) Å³
Z = 4
Mo Kα radiation
μ = 2.40 mm⁻¹
T = 173 K
0.27 × 0.24 × 0.20 mm

Data collection

Bruker SMART APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.565, T_max = 0.648
12825 measured reflections
3297 independent reflections
2990 reflections with I > 2σ(I)
R_int = 0.031

Refinement

R[F² > 2σ(F²)] = 0.029
wR(F²) = 0.077
S = 1.11
3297 reflections
182 parameters
H-atom parameters constrained
Δρ_max = 0.58 e Å⁻³
Δρ_min = −1.56 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C5—H5⋯O1ⁱ	0.93	2.55	3.472 (3)	170
C9—H9C⋯O2ⁱⁱ	0.96	2.53	3.277 (3)	135
Symmetry codes: (i) $[-x+2, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (ii) $[x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ .

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/S1600536810024931/cs2129sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810024931/cs2129Isup2.hkl

checkCIF report

Comment top

Molecules containing benzofuran skeleton show variouspharmacological properties such as antifungal (Aslam et al., 2006), antitumor and antiviral (Galal et al.., 2009), antimicrobial (Khan et al.., 2005) activity, and 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,c), we report the crystal structure of the title compound (Fig. 1).

The benzofuran unit is essentially planar, with a mean deviation of 0.008 (2) 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 [83.37 (7)°] 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 benzene H atom and the furan O atom with a C5—H5···O1ⁱ, and the second one between the methyl H atom and the oxygen of the S═O unit, with a C9—H9C···O2ⁱⁱ, respectively (Table 1). The molecular packing (Fig. 2) is also stabilized by an I···O halogen bonding between the iodine and the oxygen of the S═O unit [I···O2^v = 3.255 (2) Å; C4—I···O2^v = 164.42 (8)°] (Politzer et al., 2007). The crystal packing (Fig. 3) also exhibits intermolecular C—F···π interactions between the fluorine and the benzene ring of an adjacent benzofuran system, with a C13—F···Cg2^vii distance of 3.068 (2) Å (Cg2 is the centroid of the C2–C7 benzene ring), and aromatic π–π interactions between the furan and the benzene rings of the adjacent benzofuran systems, with a Cg1···Cg2^viii distance of 3.636 (2) Å (Cg1 is the centroid of the C1/C2/C7/O1/C8 furan ring).

Related literature top

For the crystal structures of similar 3-(4-fluorophenylsulfinyl)-2-methyl-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). For a review of halogen bonding, see: Politzer et al. (2007).

Experimental top

77% 3-Chloroperoxybenzoic acid (166 mg, 1.0 mmol) was added in small portions to a stirred solution of 3-(4-fluorophenylsulfanyl)–5-iodo-2-methyl-1-benzofuran (346 mg, 0.9 mmol) in dichloromethane (30 mL) at 273 K. After being stirred at room temperature for 3h, 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 77%, m.p. 428–429 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 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 I···O interactions (dotted lines) in the crystal structure of the title compound. [Symmetry codes: (i) - x + 2, y - 1/2, - z + 3/2; (ii) x, - y + 3/2, z + 1/2; (iii) - x + 2, y + 1/2, - z + 3/2; (iv) x, - y + 3/2, z - 1/2; (v) x, - y + 1/2, z + 1/2; (vi) x, - y + 1/2, z - 1/2.]
	Fig. 3. C—F···π and π–π interactions (dotted lines) in the crystal structure of the title compound. Cg denotes the ring centroid. [Symmetry codes: (vii) - x + 1, - y +1 , - z + 1; (viii) - x + 2, - y + 1, - z + 1.]

3-(4-Fluorophenylsulfinyl)-5-iodo-2-methyl-1-benzofuran top

Crystal data top

C₁₅H₁₀FIO₂S	F(000) = 776
M_r = 400.19	D_x = 1.861 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 8763 reflections
a = 13.1665 (4) Å	θ = 2.4–27.6°
b = 11.4338 (4) Å	µ = 2.40 mm⁻¹
c = 9.9296 (3) Å	T = 173 K
β = 107.181 (1)°	Block, colourless
V = 1428.13 (8) Å³	0.27 × 0.24 × 0.20 mm
Z = 4

Data collection top

Bruker SMART APEXII CCD diffractometer	3297 independent reflections
Radiation source: rotating anode	2990 reflections with I > 2σ(I)
Graphite multilayer monochromator	R_int = 0.031
Detector resolution: 10.0 pixels mm^-1	θ_max = 27.6°, θ_min = 1.6°
ϕ and ω scans	h = −15→17
Absorption correction: multi-scan (SADABS; Bruker, 2009)	k = −14→14
T_min = 0.565, T_max = 0.648	l = −12→12
12825 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)] = 0.029	Hydrogen site location: difference Fourier map
wR(F²) = 0.077	H-atom parameters constrained
S = 1.11	w = 1/[σ²(F_o²) + (0.0381P)² + 1.2193P] where P = (F_o² + 2F_c²)/3
3297 reflections	(Δ/σ)_max < 0.001
182 parameters	Δρ_max = 0.58 e Å⁻³
0 restraints	Δρ_min = −1.56 e Å⁻³

Crystal data top

C₁₅H₁₀FIO₂S	V = 1428.13 (8) Å³
M_r = 400.19	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 13.1665 (4) Å	µ = 2.40 mm⁻¹
b = 11.4338 (4) Å	T = 173 K
c = 9.9296 (3) Å	0.27 × 0.24 × 0.20 mm
β = 107.181 (1)°

Data collection top

Bruker SMART APEXII CCD diffractometer	3297 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	2990 reflections with I > 2σ(I)
T_min = 0.565, T_max = 0.648	R_int = 0.031
12825 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.029	0 restraints
wR(F²) = 0.077	H-atom parameters constrained
S = 1.11	Δρ_max = 0.58 e Å⁻³
3297 reflections	Δρ_min = −1.56 e Å⁻³
182 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
I	0.774810 (15)	0.162106 (16)	0.53507 (2)	0.03259 (8)
S	0.70499 (5)	0.67499 (6)	0.22747 (6)	0.02368 (14)
F	0.31812 (15)	0.49689 (19)	0.3339 (2)	0.0480 (5)
O1	0.94047 (15)	0.67042 (15)	0.57609 (19)	0.0249 (4)
O2	0.71831 (16)	0.60325 (19)	0.10757 (19)	0.0318 (4)
C1	0.8028 (2)	0.6377 (2)	0.3837 (2)	0.0213 (5)
C2	0.82677 (18)	0.5281 (2)	0.4598 (2)	0.0195 (5)
C3	0.78672 (19)	0.4142 (2)	0.4425 (2)	0.0219 (5)
H3	0.7309	0.3931	0.3643	0.026*
C4	0.8338 (2)	0.3340 (2)	0.5469 (3)	0.0233 (5)
C5	0.9195 (2)	0.3625 (2)	0.6643 (3)	0.0263 (5)
H5	0.9488	0.3058	0.7318	0.032*
C6	0.9608 (2)	0.4746 (2)	0.6804 (3)	0.0259 (5)
H6	1.0184	0.4951	0.7567	0.031*
C7	0.91229 (19)	0.5544 (2)	0.5777 (2)	0.0214 (5)
C8	0.8732 (2)	0.7187 (2)	0.4571 (3)	0.0229 (5)
C9	0.8903 (2)	0.8441 (2)	0.4345 (3)	0.0292 (6)
H9A	0.8451	0.8675	0.3436	0.044*
H9B	0.9632	0.8567	0.4387	0.044*
H9C	0.8735	0.8896	0.5064	0.044*
C10	0.59180 (19)	0.6152 (2)	0.2691 (2)	0.0226 (5)
C11	0.5564 (2)	0.6657 (2)	0.3746 (3)	0.0298 (6)
H11	0.5945	0.7263	0.4293	0.036*
C12	0.4639 (2)	0.6250 (3)	0.3973 (3)	0.0330 (6)
H12	0.4393	0.6570	0.4679	0.040*
C13	0.4092 (2)	0.5362 (3)	0.3133 (3)	0.0310 (6)
C14	0.4427 (2)	0.4850 (3)	0.2094 (3)	0.0315 (6)
H14	0.4039	0.4247	0.1549	0.038*
C15	0.5360 (2)	0.5251 (2)	0.1870 (3)	0.0267 (5)
H15	0.5607	0.4916	0.1173	0.032*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
I	0.03251 (12)	0.02096 (12)	0.04268 (13)	0.00056 (6)	0.00859 (9)	0.00097 (7)
S	0.0267 (3)	0.0237 (3)	0.0189 (3)	0.0016 (2)	0.0038 (2)	0.0032 (2)
F	0.0320 (9)	0.0613 (13)	0.0562 (11)	−0.0066 (9)	0.0216 (8)	−0.0055 (10)
O1	0.0236 (9)	0.0244 (10)	0.0240 (8)	−0.0017 (7)	0.0031 (7)	−0.0028 (7)
O2	0.0364 (10)	0.0411 (12)	0.0203 (8)	−0.0014 (9)	0.0122 (8)	−0.0030 (8)
C1	0.0214 (11)	0.0211 (12)	0.0208 (11)	0.0004 (9)	0.0056 (9)	0.0009 (9)
C2	0.0191 (11)	0.0211 (12)	0.0182 (10)	0.0021 (9)	0.0055 (8)	0.0003 (9)
C3	0.0219 (11)	0.0216 (12)	0.0208 (11)	0.0012 (9)	0.0043 (9)	−0.0012 (9)
C4	0.0250 (12)	0.0193 (13)	0.0258 (12)	0.0005 (9)	0.0079 (10)	−0.0022 (9)
C5	0.0293 (13)	0.0265 (13)	0.0215 (11)	0.0076 (11)	0.0050 (10)	0.0024 (10)
C6	0.0243 (12)	0.0286 (14)	0.0206 (11)	0.0034 (10)	0.0004 (9)	−0.0028 (10)
C7	0.0206 (11)	0.0230 (12)	0.0207 (10)	0.0009 (9)	0.0064 (9)	−0.0027 (9)
C8	0.0231 (12)	0.0247 (13)	0.0220 (11)	0.0013 (10)	0.0085 (9)	−0.0013 (9)
C9	0.0294 (14)	0.0238 (14)	0.0353 (14)	−0.0034 (10)	0.0111 (11)	−0.0010 (10)
C10	0.0234 (12)	0.0233 (13)	0.0183 (10)	0.0050 (10)	0.0017 (9)	0.0027 (9)
C11	0.0339 (15)	0.0285 (15)	0.0256 (12)	0.0020 (11)	0.0067 (11)	−0.0051 (10)
C12	0.0354 (15)	0.0368 (16)	0.0295 (13)	0.0068 (13)	0.0138 (11)	−0.0024 (12)
C13	0.0221 (12)	0.0380 (16)	0.0324 (13)	0.0038 (11)	0.0074 (10)	0.0035 (12)
C14	0.0272 (13)	0.0327 (15)	0.0319 (13)	−0.0027 (11)	0.0045 (11)	−0.0071 (11)
C15	0.0260 (12)	0.0295 (14)	0.0225 (11)	0.0034 (10)	0.0039 (10)	−0.0049 (10)

Geometric parameters (Å, º) top

I—C4	2.104 (2)	C6—C7	1.376 (4)
I—O2ⁱ	3.255 (2)	C6—H6	0.9300
S—O2	1.4981 (19)	C8—C9	1.478 (4)
S—C1	1.751 (2)	C9—H9A	0.9600
S—C10	1.795 (3)	C9—H9B	0.9600
F—C13	1.351 (3)	C9—H9C	0.9600
O1—C8	1.366 (3)	C10—C15	1.383 (4)
O1—C7	1.379 (3)	C10—C11	1.391 (4)
C1—C8	1.360 (4)	C11—C12	1.383 (4)
C1—C2	1.449 (3)	C11—H11	0.9300
C2—C3	1.396 (3)	C12—C13	1.375 (4)
C2—C7	1.396 (3)	C12—H12	0.9300
C3—C4	1.386 (3)	C13—C14	1.368 (4)
C3—H3	0.9300	C14—C15	1.389 (4)
C4—C5	1.401 (4)	C14—H14	0.9300
C5—C6	1.383 (4)	C15—H15	0.9300
C5—H5	0.9300

C4—I—O2ⁱ	164.42 (8)	C1—C8—C9	133.5 (2)
O2—S—C1	110.03 (12)	O1—C8—C9	115.8 (2)
O2—S—C10	105.95 (12)	C8—C9—H9A	109.5
C1—S—C10	98.44 (11)	C8—C9—H9B	109.5
C8—O1—C7	106.94 (19)	H9A—C9—H9B	109.5
C8—C1—C2	107.5 (2)	C8—C9—H9C	109.5
C8—C1—S	121.0 (2)	H9A—C9—H9C	109.5
C2—C1—S	131.48 (19)	H9B—C9—H9C	109.5
C3—C2—C7	119.1 (2)	C15—C10—C11	121.0 (3)
C3—C2—C1	136.5 (2)	C15—C10—S	118.73 (19)
C7—C2—C1	104.4 (2)	C11—C10—S	120.1 (2)
C4—C3—C2	117.1 (2)	C12—C11—C10	119.3 (3)
C4—C3—H3	121.4	C12—C11—H11	120.3
C2—C3—H3	121.4	C10—C11—H11	120.3
C3—C4—C5	122.8 (2)	C13—C12—C11	118.6 (3)
C3—C4—I	120.02 (19)	C13—C12—H12	120.7
C5—C4—I	117.21 (19)	C11—C12—H12	120.7
C6—C5—C4	120.3 (2)	F—C13—C14	118.1 (3)
C6—C5—H5	119.9	F—C13—C12	118.9 (3)
C4—C5—H5	119.9	C14—C13—C12	123.0 (3)
C7—C6—C5	116.6 (2)	C13—C14—C15	118.5 (3)
C7—C6—H6	121.7	C13—C14—H14	120.8
C5—C6—H6	121.7	C15—C14—H14	120.8
C6—C7—O1	125.4 (2)	C10—C15—C14	119.5 (2)
C6—C7—C2	124.1 (2)	C10—C15—H15	120.2
O1—C7—C2	110.5 (2)	C14—C15—H15	120.2
C1—C8—O1	110.7 (2)

Symmetry code: (i) x, −y+1/2, z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···O1ⁱⁱ	0.93	2.55	3.472 (3)	170
C9—H9C···O2ⁱⁱⁱ	0.96	2.53	3.277 (3)	135

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

Experimental details

Crystal data
Chemical formula	C₁₅H₁₀FIO₂S
M_r	400.19
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	173
a, b, c (Å)	13.1665 (4), 11.4338 (4), 9.9296 (3)
β (°)	107.181 (1)
V (Å³)	1428.13 (8)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	2.40
Crystal size (mm)	0.27 × 0.24 × 0.20

Data collection
Diffractometer	Bruker SMART APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.565, 0.648
No. of measured, independent and observed [I > 2σ(I)] reflections	12825, 3297, 2990
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.651

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.029, 0.077, 1.11
No. of reflections	3297
No. of parameters	182
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.58, −1.56

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

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···O1ⁱ	0.93	2.55	3.472 (3)	169.9
C9—H9C···O2ⁱⁱ	0.96	2.53	3.277 (3)	134.6

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

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 GmbH, 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, o472. Web of Science CSD CrossRef IUCr Journals Google Scholar
Choi, H. D., Seo, P. J., Son, B. W. & Lee, U. (2010b). Acta Cryst. E66, o543. Web of Science CSD CrossRef IUCr Journals Google Scholar
Choi, H. D., Seo, P. J., Son, B. W. & Lee, U. (2010c). Acta Cryst. E66, o564. 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
Politzer, P., Lane, P., Concha, M. C., Ma, Y. & Murray, J. S. (2007). J. Mol. Model., 13, 305–311. 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 o1876

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