5-Fluoro-3-methyl­sulfinyl-2-phenyl-1-benzofuran

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

doi:10.1107/S1600536809028189

organic compounds

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ISSN: 2056-9890

Volume 65| Part 8| August 2009| Page o1957

doi:10.1107/S1600536809028189

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5-Fluoro-3-methylsulfinyl-2-phenyl-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 3 July 2009; accepted 17 July 2009; online 22 July 2009)

In the title compound, C₁₅H₁₁FO₂S, the O atom and the methyl group of the methylsulfinyl substituent lie on opposite sides of the plane of the benzofuran fragment. The 2-phenyl ring is rotated out of the benzofuran plane, making a dihedral angle of 32.1 (2)°. The crystal structure is stabilized by aromatic π–π interactions between the benzene rings of neighbouring molecules [centroid–centroid distance = 3.690 (5) Å]. In addition, the crystal structure exhibits intermolecular C—H⋯O and C—H⋯F interactions.

Related literature

For the crystal structures of similar 5-halo-3-methylsulfinyl-2-phenyl-1-benzofuran derivatives, see: Choi et al. (2007a ,b ). For the biological and pharmacological activity of benzofuran compounds, see: Howlett et al. (1999 ); Ward (1997 ).

Experimental

Crystal data

C₁₅H₁₁FO₂S
M_r = 274.30
Monoclinic, P 2₁ /c
a = 8.507 (4) Å
b = 16.655 (7) Å
c = 9.553 (4) Å
β = 113.732 (5)°
V = 1239.1 (9) Å³
Z = 4
Mo Kα radiation
μ = 0.27 mm⁻¹
T = 273 K
0.20 × 0.10 × 0.10 mm

Data collection

Bruker SMART CCD diffractometer
Absorption correction: none
8954 measured reflections
2251 independent reflections
1478 reflections with I > 2σ(I)
R_int = 0.133

Refinement

R[F² > 2σ(F²)] = 0.061
wR(F²) = 0.157
S = 1.07
2251 reflections
173 parameters
H-atom parameters constrained
Δρ_max = 0.64 e Å⁻³
Δρ_min = −0.34 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C5—H5⋯O2ⁱ	0.93	2.48	3.282 (5)	145
C12—H12⋯O2ⁱⁱ	0.93	2.48	3.371 (5)	160
C13—H13⋯O2ⁱⁱⁱ	0.93	2.64	3.555 (5)	170
C15—H15B⋯O1^iv	0.96	2.67	3.493 (6)	144
C15—H15A⋯F^v	0.96	2.62	3.509 (6)	155
Symmetry codes: (i) $[-x+2, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (ii) x-1, y, z-1; (iii) $[x-1, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]$ ; (iv) -x+1, -y+1, -z+1; (v) -x+2, -y+1, -z+2.

Data collection: SMART (Bruker, 2001 ); cell refinement: SAINT (Bruker, 2001); 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/S1600536809028189/er2071sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809028189/er2071Isup2.hkl

checkCIF report

Comment top

The benzofuran ring systems have been received considerable attenttion in the field of their biological and pharmacological properties (Howlett et al., 1999; Ward, 1997). This work is related to our communications on the synthesis and structures of 5-halo-3-methylsulfinyl-2-phenyl-1-benzofuran analogues, viz. 5-bromo-3-methylsulfinyl-2-phenyl-1-benzofuran (Choi et al., 2007a) and 5-iodo-3-methylsulfinyl-2-phenyl-1-benzofuran (Choi et al., 2007b). Here we report the crystal structure of the title compound, 5-fluoro-3-methylsulfinyl-2-phenyl-1-benzofuran (Fig. 1).

The benzofuran unit is essentially planar, with a mean deviation of 0.011 (3) Å from the least-squares plane defined by the nine constituent atoms. The dihedral angle formed by the planes of the benzofuran and the phenyl rings is 3.690 (5)°. The crystal packing (Fig. 2) is stabilized by aromatic π–π interactions between the benzene rings of the adjacent molecules, with a Cg···Cg distance of 3.690 (5) Å (Cg is the centroid of the C2–C7 benzene ring). The crystal packing (Fig. 2) exhibits four C–H···O and an C–H···F intermolecular interactions (Table 1 and Fig. 2).

Related literature top

For the crystal structures of similar 5-halo-3-methylsulfinyl-2-phenyl-1-benzofuran derivatives, see: Choi et al. (2007a,b). For the biological and pharmacological activity of benzofuran compounds, see: Howlett et al. (1999); Ward (1997).

Experimental top

The 77% 3-chloroperoxybenzoic acid (291 mg, 1.3 mmol) was added in small portions to a stirred solution of 5-fluoro-3-methylsulfanyl-2-phenyl-1-benzofuran (310 mg, 1.2 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 in vacuum. The residue was purified by column chromatography (hexane-ethyl acetate, 1 : 1 v/v) to afford the title compound as a colorless solid [yield 83%, m.p. 462-463 K; R_f = 0.47 (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 tetrahydrofuran at room temperature.

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

	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 spheres of arbitrary radius.
	Fig. 2. π–π, C–H···O, and C–H···F interactions (dotted lines) in the crystal structure of title compound. Cg denotes the ring centroid. [Symmetry code: (i) -x + 2, y - 1/2, -z + 3/2; (ii) x - 1, y, z - 1; (iii) x - 1, -y + 3/2, z - 1/2 ; (iv) -x + 1, -y + 1, -z + 1; (v) -x + 2, -y + 1, -z + 2; (vi) -x + 2, -y + 1, -z + 1; (vii) -x + 2, y + 1/2, -z + 3/2.]

5-Fluoro-3-methylsulfinyl-2-phenyl-1-benzofuran top

Crystal data top

C₁₅H₁₁FO₂S	F(000) = 568
M_r = 274.30	D_x = 1.470 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2317 reflections
a = 8.507 (4) Å	θ = 2.5–26.7°
b = 16.655 (7) Å	µ = 0.27 mm⁻¹
c = 9.553 (4) Å	T = 273 K
β = 113.732 (5)°	Block, colourless
V = 1239.1 (9) Å³	0.20 × 0.10 × 0.10 mm
Z = 4

Data collection top

Bruker SMART CCD diffractometer	1478 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.133
Graphite monochromator	θ_max = 25.5°, θ_min = 2.5°
Detector resolution: 10.0 pixels mm^-1	h = −10→10
ϕ and ω scans	k = −20→20
8954 measured reflections	l = −11→11
2251 independent 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)] = 0.061	Hydrogen site location: difference Fourier map
wR(F²) = 0.157	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0649P)² + 1.1956P] where P = (F_o² + 2F_c²)/3
2251 reflections	(Δ/σ)_max < 0.001
173 parameters	Δρ_max = 0.64 e Å⁻³
0 restraints	Δρ_min = −0.34 e Å⁻³

Crystal data top

C₁₅H₁₁FO₂S	V = 1239.1 (9) Å³
M_r = 274.30	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 8.507 (4) Å	µ = 0.27 mm⁻¹
b = 16.655 (7) Å	T = 273 K
c = 9.553 (4) Å	0.20 × 0.10 × 0.10 mm
β = 113.732 (5)°

Data collection top

Bruker SMART CCD diffractometer	1478 reflections with I > 2σ(I)
8954 measured reflections	R_int = 0.133
2251 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.061	0 restraints
wR(F²) = 0.157	H-atom parameters constrained
S = 1.07	Δρ_max = 0.64 e Å⁻³
2251 reflections	Δρ_min = −0.34 e Å⁻³
173 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
S	0.68313 (13)	0.69115 (6)	0.59163 (12)	0.0254 (3)
F	1.1429 (3)	0.43327 (15)	0.9193 (3)	0.0410 (7)
O1	0.6667 (3)	0.49692 (15)	0.3511 (3)	0.0239 (6)
O2	0.8646 (4)	0.71756 (17)	0.6700 (4)	0.0382 (8)
C1	0.6897 (5)	0.5933 (2)	0.5247 (4)	0.0195 (8)
C2	0.8108 (5)	0.5306 (2)	0.6026 (4)	0.0212 (8)
C3	0.9321 (5)	0.5180 (2)	0.7509 (5)	0.0255 (9)
H3	0.9490	0.5548	0.8289	0.031*
C4	1.0255 (5)	0.4483 (3)	0.7757 (5)	0.0280 (9)
C5	1.0078 (5)	0.3919 (2)	0.6625 (5)	0.0292 (10)
H5	1.0754	0.3458	0.6864	0.035*
C6	0.8909 (5)	0.4045 (2)	0.5168 (5)	0.0275 (9)
H6	0.8777	0.3682	0.4388	0.033*
C7	0.7926 (5)	0.4737 (2)	0.4896 (4)	0.0224 (8)
C8	0.6087 (5)	0.5703 (2)	0.3762 (4)	0.0207 (8)
C9	0.4741 (5)	0.6076 (2)	0.2420 (4)	0.0209 (8)
C10	0.4709 (5)	0.5957 (3)	0.0963 (5)	0.0303 (10)
H10	0.5542	0.5640	0.0838	0.036*
C11	0.3445 (6)	0.6311 (3)	−0.0293 (5)	0.0371 (11)
H11	0.3438	0.6236	−0.1260	0.044*
C12	0.2182 (5)	0.6779 (3)	−0.0119 (5)	0.0339 (10)
H12	0.1329	0.7016	−0.0966	0.041*
C13	0.2205 (5)	0.6887 (2)	0.1312 (5)	0.0269 (9)
H13	0.1353	0.7196	0.1428	0.032*
C14	0.3464 (5)	0.6547 (2)	0.2579 (5)	0.0238 (9)
H14	0.3467	0.6631	0.3542	0.029*
C15	0.6122 (6)	0.6672 (3)	0.7391 (5)	0.0403 (12)
H15A	0.6921	0.6308	0.8104	0.060*
H15B	0.5009	0.6426	0.6947	0.060*
H15C	0.6055	0.7155	0.7914	0.060*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S	0.0240 (5)	0.0220 (5)	0.0278 (6)	−0.0001 (4)	0.0079 (4)	−0.0029 (4)
F	0.0295 (14)	0.0525 (17)	0.0367 (15)	0.0104 (11)	0.0086 (12)	0.0157 (12)
O1	0.0211 (14)	0.0263 (15)	0.0259 (15)	0.0005 (11)	0.0112 (12)	−0.0010 (11)
O2	0.0293 (17)	0.0332 (17)	0.048 (2)	−0.0098 (13)	0.0108 (15)	−0.0085 (14)
C1	0.0155 (18)	0.0189 (19)	0.023 (2)	0.0004 (14)	0.0071 (16)	0.0009 (15)
C2	0.0142 (19)	0.026 (2)	0.026 (2)	−0.0018 (15)	0.0110 (17)	0.0027 (15)
C3	0.020 (2)	0.031 (2)	0.027 (2)	−0.0018 (16)	0.0115 (18)	0.0017 (16)
C4	0.016 (2)	0.040 (2)	0.028 (2)	0.0038 (17)	0.0091 (18)	0.0123 (18)
C5	0.027 (2)	0.031 (2)	0.039 (3)	0.0073 (17)	0.022 (2)	0.0095 (18)
C6	0.028 (2)	0.025 (2)	0.036 (2)	0.0015 (17)	0.0193 (19)	−0.0002 (17)
C7	0.020 (2)	0.026 (2)	0.026 (2)	−0.0025 (15)	0.0139 (18)	0.0039 (16)
C8	0.021 (2)	0.0170 (19)	0.028 (2)	0.0004 (15)	0.0135 (17)	0.0001 (15)
C9	0.0177 (19)	0.023 (2)	0.022 (2)	−0.0030 (15)	0.0075 (16)	0.0018 (15)
C10	0.026 (2)	0.040 (2)	0.026 (2)	0.0028 (18)	0.0120 (19)	−0.0037 (18)
C11	0.035 (3)	0.053 (3)	0.025 (2)	0.000 (2)	0.014 (2)	0.000 (2)
C12	0.026 (2)	0.037 (3)	0.034 (3)	−0.0002 (18)	0.007 (2)	0.0096 (18)
C13	0.016 (2)	0.032 (2)	0.034 (2)	0.0027 (16)	0.0114 (18)	0.0044 (18)
C14	0.017 (2)	0.029 (2)	0.026 (2)	−0.0027 (16)	0.0107 (18)	−0.0009 (16)
C15	0.047 (3)	0.043 (3)	0.044 (3)	0.003 (2)	0.033 (2)	−0.008 (2)

Geometric parameters (Å, º) top

S—O2	1.486 (3)	C6—H6	0.9300
S—C1	1.760 (4)	C8—C9	1.470 (5)
S—C15	1.786 (5)	C9—C10	1.395 (5)
F—C4	1.357 (4)	C9—C14	1.397 (5)
O1—C8	1.375 (4)	C10—C11	1.380 (6)
O1—C7	1.381 (5)	C10—H10	0.9300
C1—C8	1.358 (5)	C11—C12	1.390 (6)
C1—C2	1.446 (5)	C11—H11	0.9300
C2—C3	1.392 (5)	C12—C13	1.372 (6)
C2—C7	1.398 (5)	C12—H12	0.9300
C3—C4	1.373 (6)	C13—C14	1.374 (5)
C3—H3	0.9300	C13—H13	0.9300
C4—C5	1.393 (6)	C14—H14	0.9300
C5—C6	1.363 (6)	C15—H15A	0.9600
C5—H5	0.9300	C15—H15B	0.9600
C6—C7	1.385 (5)	C15—H15C	0.9600

O2—S—C1	106.19 (17)	C1—C8—C9	133.0 (3)
O2—S—C15	106.3 (2)	O1—C8—C9	115.6 (3)
C1—S—C15	98.6 (2)	C10—C9—C14	119.0 (4)
C8—O1—C7	106.0 (3)	C10—C9—C8	120.4 (3)
C8—C1—C2	106.9 (3)	C14—C9—C8	120.6 (3)
C8—C1—S	124.3 (3)	C11—C10—C9	120.2 (4)
C2—C1—S	127.0 (3)	C11—C10—H10	119.9
C3—C2—C7	119.4 (4)	C9—C10—H10	119.9
C3—C2—C1	135.7 (4)	C10—C11—C12	120.3 (4)
C7—C2—C1	104.9 (3)	C10—C11—H11	119.8
C4—C3—C2	116.3 (4)	C12—C11—H11	119.8
C4—C3—H3	121.9	C13—C12—C11	119.4 (4)
C2—C3—H3	121.9	C13—C12—H12	120.3
F—C4—C3	118.0 (4)	C11—C12—H12	120.3
F—C4—C5	117.8 (4)	C12—C13—C14	121.1 (4)
C3—C4—C5	124.2 (4)	C12—C13—H13	119.5
C6—C5—C4	119.7 (4)	C14—C13—H13	119.5
C6—C5—H5	120.2	C13—C14—C9	120.0 (4)
C4—C5—H5	120.2	C13—C14—H14	120.0
C5—C6—C7	117.2 (4)	C9—C14—H14	120.0
C5—C6—H6	121.4	S—C15—H15A	109.5
C7—C6—H6	121.4	S—C15—H15B	109.5
O1—C7—C6	126.1 (4)	H15A—C15—H15B	109.5
O1—C7—C2	110.6 (3)	S—C15—H15C	109.5
C6—C7—C2	123.3 (4)	H15A—C15—H15C	109.5
C1—C8—O1	111.5 (3)	H15B—C15—H15C	109.5

O2—S—C1—C8	−123.7 (3)	C3—C2—C7—C6	−0.5 (6)
C15—S—C1—C8	126.4 (4)	C1—C2—C7—C6	177.9 (3)
O2—S—C1—C2	39.2 (4)	C2—C1—C8—O1	0.4 (4)
C15—S—C1—C2	−70.7 (4)	S—C1—C8—O1	166.2 (3)
C8—C1—C2—C3	178.7 (4)	C2—C1—C8—C9	179.9 (4)
S—C1—C2—C3	13.4 (6)	S—C1—C8—C9	−14.3 (6)
C8—C1—C2—C7	0.6 (4)	C7—O1—C8—C1	−1.3 (4)
S—C1—C2—C7	−164.6 (3)	C7—O1—C8—C9	179.1 (3)
C7—C2—C3—C4	−0.8 (5)	C1—C8—C9—C10	147.8 (4)
C1—C2—C3—C4	−178.6 (4)	O1—C8—C9—C10	−32.7 (5)
C2—C3—C4—F	−178.9 (3)	C1—C8—C9—C14	−32.9 (6)
C2—C3—C4—C5	1.3 (6)	O1—C8—C9—C14	146.6 (3)
F—C4—C5—C6	179.8 (3)	C14—C9—C10—C11	0.8 (6)
C3—C4—C5—C6	−0.4 (6)	C8—C9—C10—C11	−179.8 (4)
C4—C5—C6—C7	−1.0 (6)	C9—C10—C11—C12	−0.8 (7)
C8—O1—C7—C6	−177.6 (4)	C10—C11—C12—C13	0.1 (7)
C8—O1—C7—C2	1.7 (4)	C11—C12—C13—C14	0.6 (6)
C5—C6—C7—O1	−179.3 (3)	C12—C13—C14—C9	−0.6 (6)
C5—C6—C7—C2	1.4 (6)	C10—C9—C14—C13	−0.1 (6)
C3—C2—C7—O1	−179.9 (3)	C8—C9—C14—C13	−179.5 (3)
C1—C2—C7—O1	−1.5 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···O2ⁱ	0.93	2.48	3.282 (5)	145
C12—H12···O2ⁱⁱ	0.93	2.48	3.371 (5)	160
C13—H13···O2ⁱⁱⁱ	0.93	2.64	3.555 (5)	170
C15—H15B···O1^iv	0.96	2.67	3.493 (6)	144
C15—H15A···F^v	0.96	2.62	3.509 (6)	155

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

Experimental details

Crystal data
Chemical formula	C₁₅H₁₁FO₂S
M_r	274.30
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	273
a, b, c (Å)	8.507 (4), 16.655 (7), 9.553 (4)
β (°)	113.732 (5)
V (Å³)	1239.1 (9)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.27
Crystal size (mm)	0.20 × 0.10 × 0.10

Data collection
Diffractometer	Bruker SMART CCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	8954, 2251, 1478
R_int	0.133
(sin θ/λ)_max (Å⁻¹)	0.606

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.061, 0.157, 1.07
No. of reflections	2251
No. of parameters	173
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.64, −0.34

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···A	D—H	H···A	D···A	D—H···A
C5—H5···O2ⁱ	0.93	2.48	3.282 (5)	144.6
C12—H12···O2ⁱⁱ	0.93	2.48	3.371 (5)	160.2
C13—H13···O2ⁱⁱⁱ	0.93	2.64	3.555 (5)	169.7
C15—H15B···O1^iv	0.96	2.67	3.493 (6)	144.3
C15—H15A···F^v	0.96	2.62	3.509 (6)	154.5

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

Acknowledgements

This work was supported by Dong-eui University (grant No. 2009AA099).

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