(2E)-1-(5-Chloro­thio­phen-2-yl)-3-(2,3-dimeth­oxy­phen­yl)prop-2-en-1-one

Prabhu, A.N.; Jayarama, A.; Sankolli, R.; Guru Row, T.N.; Upadhyaya, V.

doi:10.1107/S1600536811037135

organic compounds

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ISSN: 2056-9890

Volume 67| Part 10| October 2011| Page o2665

https://doi.org/10.1107/S1600536811037135

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(2E)-1-(5-Chlorothiophen-2-yl)-3-(2,3-dimethoxyphenyl)prop-2-en-1-one

A. N. Prabhu,^a A. Jayarama,^b Ravish Sankolli,^c T. N. Guru Row ^c and V. Upadhyaya ^a ^*

^aPhysics Department, Manipal Institute of Technology, Manipal University, Manipal 576 104, India, ^bDepartment of Physics, Mangalore Institute of Technology & Engineering (MITE), Badagamijar, Moodabidri, Karnataka, India, and ^cSolid State and Sructural Chemistry Unit, Indian Institute of Science, Bangalore 560 012, India
^*Correspondence e-mail: v.upadhyaya@manipal.edu

(Received 30 July 2011; accepted 13 September 2011; online 17 September 2011)

In the title compound, C₁₅H₁₃ClO₃S, the chlorothiophene and dimethoxyphenyl groups are linked by a prop-2-en-1-one group. The C=C double bond exhibits an E conformation. The molecule is non-planar, with a dihedral angle of 31.12 (5)° between the chlorothiophene and dimethoxyphenyl rings. The methoxy group at position 3 is coplanar with the benzene ring to which it is attached, with a C—O—C—C torsion angle of −3.8 (3)°. The methoxy group attached at position 2 of the benzene ring is in a (+)synclinal conformation, as indicated by the C—O—C—C torsion angle of −73.6 (2)°. In the crystal, two different C—H⋯O intermolecular interactions generate chains of molecules extending along the b axis.

Related literature

For general background to chalcones and their biological properties, see: Choudary et al. (1999 ); Tomazela et al. (2000 ). For a related structure, see: Benmekhbi et al. (2009 ).

Experimental

Crystal data

C₁₅H₁₃ClO₃S
M_r = 308.76
Monoclinic, P 2₁ /c
a = 11.6139 (8) Å
b = 8.5605 (5) Å
c = 14.4174 (9) Å
β = 99.907 (2)°
V = 1412.02 (16) Å³
Z = 4
Mo Kα radiation
μ = 0.42 mm⁻¹
T = 296 K
0.20 × 0.18 × 0.16 mm

Data collection

Bruker SMART APEX CCD detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 1998 ) T_min = 0.920, T_max = 0.936
9286 measured reflections
3087 independent reflections
2348 reflections with I > 2σ(I)
R_int = 0.026

Refinement

R[F² > 2σ(F²)] = 0.038
wR(F²) = 0.102
S = 1.07
3087 reflections
183 parameters
H-atom parameters constrained
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.26 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯O1ⁱ	0.93	2.53	3.209 (2)	130
C15—H15A⋯O2ⁱⁱ	0.96	2.55	3.423 (3)	151
Symmetry codes: (i) $[x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ ; (ii) $[-x+2, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Data collection: SMART (Bruker, 1998); cell refinement: SAINT-Plus (Bruker, 1998); data reduction: SAINT-Plus; 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 CAMERON (Watkin et al., 1996 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536811037135/pv2439sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811037135/pv2439Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536811037135/pv2439Isup3.cml

checkCIF report

Comment top

Chalcones represent one of the most abundant and ubiquitous group of natural products (Tomazela, et al., 2000). In the past few years, they have been shown to possess interesting biological properties and synthetic intermediates (Choudary, et al., 1999). In the title compound (Fig. 1), the chlorothiophene and dimethoxyphenyl groups are linked by a prop-2-en-1-one group. The chlorothiophene and dimethoxyphenyl rings are non-planar with the dihedral angle 31.12 (5)°. The torsion angle C15–O3–C12–C11 is 3.7 (3)° indicating that the O3 methoxy group is coplanar with the attached benzene ring. The other methoxy group at O2 is in a + synclinal conformation as indicated by the torsion angle 73.6 (2)° for C14–O2–C13–C12. The C═C double bond exhibits an E conformation (Benmekhbi, et al., 2009). The crystal structure is stabilized by two different C—H···O intermolecular interactions generating chains of molecules along the b-axis (Fig. 2).

Related literature top

For general background to chalcones and their biological properties, see: Choudary et al. (1999); Tomazela et al. (2000). For a related structure, see: Benmekhbi et al. (2009).

Experimental top

To synthesizethe the title compound, 2-acetyl-5-chlorothiophene (0.01 mol) and 2,3-dimethoxybenzaldehyde (0.01 mol) were dissolved in methanol (60 ml). Sodium hydroxide (5 ml, 20%) was then added drop wise to the solution, and it was stirred for 2 h. The contents of the flask were poured into ice-cold water, and the resulting crude solid was collected by filtration. The compound was dried and re-crystallized twice from acetone.

Structure description top

For general background to chalcones and their biological properties, see: Choudary et al. (1999); Tomazela et al. (2000). For a related structure, see: Benmekhbi et al. (2009).

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT-Plus (Bruker, 1998); data reduction: SAINT-Plus (Bruker, 1998); 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 CAMERON (Watkin et al., 1996); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. ORTEP (Farrugia, 1997) view of the title compound, showing 50% probability ellipsoids and the atom numbering scheme.
	Fig. 2. A unit cell packing of the title compound showing intermolecular interactions with dotted lines. H-atoms not involved in hydrogen bonding have been excluded for clarity.

(2E)-1-(5-Chlorothiophen-2-yl)-3-(2,3-dimethoxyphenyl)prop-2-en-1-one top

Crystal data top

C₁₅H₁₃ClO₃S	F(000) = 640
M_r = 308.76	D_x = 1.452 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3087 reflections
a = 11.6139 (8) Å	θ = 1.8–27.0°
b = 8.5605 (5) Å	µ = 0.42 mm⁻¹
c = 14.4174 (9) Å	T = 296 K
β = 99.907 (2)°	Block, yellow
V = 1412.02 (16) Å³	0.20 × 0.18 × 0.16 mm
Z = 4

Data collection top

Bruker SMART APEX CCD detector diffractometer	3087 independent reflections
Radiation source: fine-focus sealed tube	2348 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.026
ω scans	θ_max = 27.0°, θ_min = 1.8°
Absorption correction: multi-scan (SADABS; Bruker, 1998)	h = −14→14
T_min = 0.920, T_max = 0.936	k = −8→10
9286 measured reflections	l = −18→14

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)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.102	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0494P)² + 0.1854P] where P = (F_o² + 2F_c²)/3
3087 reflections	(Δ/σ)_max = 0.001
183 parameters	Δρ_max = 0.21 e Å⁻³
0 restraints	Δρ_min = −0.26 e Å⁻³

Crystal data top

C₁₅H₁₃ClO₃S	V = 1412.02 (16) Å³
M_r = 308.76	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 11.6139 (8) Å	µ = 0.42 mm⁻¹
b = 8.5605 (5) Å	T = 296 K
c = 14.4174 (9) Å	0.20 × 0.18 × 0.16 mm
β = 99.907 (2)°

Data collection top

Bruker SMART APEX CCD detector diffractometer	3087 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 1998)	2348 reflections with I > 2σ(I)
T_min = 0.920, T_max = 0.936	R_int = 0.026
9286 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.038	0 restraints
wR(F²) = 0.102	H-atom parameters constrained
S = 1.07	Δρ_max = 0.21 e Å⁻³
3087 reflections	Δρ_min = −0.26 e Å⁻³
183 parameters

Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
Cl1	0.22862 (5)	0.40719 (7)	1.17836 (4)	0.06157 (19)
S1	0.33583 (4)	0.57846 (6)	1.03539 (3)	0.04070 (15)
O1	0.46583 (12)	0.75106 (18)	0.91191 (10)	0.0540 (4)
O2	0.80027 (11)	0.99907 (15)	0.81682 (8)	0.0413 (3)
O3	0.97557 (11)	1.20940 (17)	0.83929 (10)	0.0509 (4)
C1	0.33815 (16)	0.5228 (2)	1.14971 (13)	0.0387 (4)
C2	0.43004 (17)	0.5799 (2)	1.21037 (13)	0.0451 (5)
H2	0.4440	0.5608	1.2748	0.054*
C3	0.50212 (16)	0.6722 (2)	1.16311 (13)	0.0427 (5)
H3	0.5697	0.7210	1.1936	0.051*
C4	0.46355 (14)	0.6834 (2)	1.06827 (12)	0.0358 (4)
C5	0.51284 (15)	0.7641 (2)	0.99432 (13)	0.0384 (4)
C6	0.61819 (15)	0.8604 (2)	1.02313 (13)	0.0407 (4)
H6	0.6442	0.8791	1.0868	0.049*
C7	0.67724 (15)	0.9214 (2)	0.96006 (13)	0.0382 (4)
H7	0.6509	0.8949	0.8975	0.046*
C8	0.77860 (15)	1.0250 (2)	0.97828 (12)	0.0357 (4)
C9	0.82092 (16)	1.0873 (2)	1.06805 (13)	0.0431 (5)
H9	0.7857	1.0592	1.1188	0.052*
C10	0.91330 (17)	1.1886 (3)	1.08140 (14)	0.0485 (5)
H10	0.9406	1.2280	1.1413	0.058*
C11	0.96713 (16)	1.2336 (2)	1.00634 (14)	0.0466 (5)
H11	1.0293	1.3036	1.0161	0.056*
C12	0.92801 (15)	1.1742 (2)	0.91742 (13)	0.0396 (4)
C13	0.83426 (15)	1.0682 (2)	0.90333 (12)	0.0347 (4)
C14	0.73927 (19)	1.0981 (3)	0.74504 (15)	0.0540 (6)
H14C	0.6614	1.1159	0.7566	0.081*
H14B	0.7358	1.0488	0.6848	0.081*
H14A	0.7796	1.1960	0.7454	0.081*
C15	1.0673 (2)	1.3220 (3)	0.84993 (18)	0.0660 (7)
H15C	1.0407	1.4174	0.8742	0.099*
H15A	1.0896	1.3416	0.7899	0.099*
H15B	1.1334	1.2829	0.8929	0.099*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0603 (3)	0.0672 (4)	0.0591 (4)	−0.0213 (3)	0.0158 (3)	0.0057 (3)
S1	0.0417 (3)	0.0445 (3)	0.0344 (3)	−0.00324 (19)	0.00221 (18)	0.0015 (2)
O1	0.0592 (8)	0.0645 (10)	0.0361 (8)	−0.0086 (7)	0.0025 (6)	0.0093 (7)
O2	0.0537 (7)	0.0392 (8)	0.0328 (7)	0.0012 (6)	0.0124 (6)	−0.0022 (6)
O3	0.0484 (8)	0.0632 (10)	0.0446 (8)	−0.0134 (7)	0.0174 (6)	0.0012 (7)
C1	0.0436 (10)	0.0360 (10)	0.0382 (10)	−0.0011 (8)	0.0122 (8)	0.0004 (8)
C2	0.0542 (11)	0.0497 (13)	0.0315 (9)	−0.0044 (9)	0.0074 (8)	−0.0008 (9)
C3	0.0438 (10)	0.0453 (12)	0.0374 (10)	−0.0059 (8)	0.0026 (8)	−0.0015 (9)
C4	0.0362 (9)	0.0339 (10)	0.0377 (10)	0.0025 (7)	0.0078 (7)	−0.0004 (8)
C5	0.0405 (9)	0.0382 (11)	0.0370 (10)	0.0060 (8)	0.0084 (8)	0.0046 (8)
C6	0.0443 (10)	0.0441 (11)	0.0343 (10)	−0.0009 (8)	0.0087 (8)	0.0013 (8)
C7	0.0438 (10)	0.0370 (11)	0.0349 (9)	0.0048 (8)	0.0101 (8)	0.0029 (8)
C8	0.0373 (9)	0.0365 (10)	0.0339 (9)	0.0061 (7)	0.0078 (7)	0.0024 (8)
C9	0.0453 (10)	0.0518 (13)	0.0333 (9)	0.0036 (9)	0.0100 (8)	0.0032 (9)
C10	0.0472 (11)	0.0616 (14)	0.0350 (10)	0.0001 (10)	0.0019 (8)	−0.0040 (9)
C11	0.0388 (10)	0.0536 (13)	0.0462 (12)	−0.0048 (8)	0.0042 (8)	−0.0020 (10)
C12	0.0374 (9)	0.0438 (12)	0.0394 (10)	0.0033 (8)	0.0116 (8)	0.0039 (9)
C13	0.0381 (9)	0.0337 (10)	0.0332 (9)	0.0049 (7)	0.0083 (7)	−0.0010 (8)
C14	0.0607 (13)	0.0573 (14)	0.0412 (11)	0.0048 (10)	0.0009 (9)	0.0042 (10)
C15	0.0583 (13)	0.0776 (18)	0.0665 (16)	−0.0211 (12)	0.0230 (11)	0.0056 (13)

Geometric parameters (Å, º) top

Cl1—C1	1.7173 (19)	C7—C8	1.461 (3)
S1—C1	1.7115 (19)	C7—H7	0.9300
S1—C4	1.7292 (18)	C8—C13	1.401 (2)
O1—C5	1.224 (2)	C8—C9	1.408 (3)
O2—C13	1.376 (2)	C9—C10	1.367 (3)
O2—C14	1.428 (2)	C9—H9	0.9300
O3—C12	1.371 (2)	C10—C11	1.394 (3)
O3—C15	1.425 (2)	C10—H10	0.9300
C1—C2	1.350 (3)	C11—C12	1.381 (3)
C2—C3	1.409 (3)	C11—H11	0.9300
C2—H2	0.9300	C12—C13	1.405 (3)
C3—C4	1.367 (2)	C14—H14C	0.9600
C3—H3	0.9300	C14—H14B	0.9600
C4—C5	1.467 (2)	C14—H14A	0.9600
C5—C6	1.474 (3)	C15—H15C	0.9600
C6—C7	1.336 (3)	C15—H15A	0.9600
C6—H6	0.9300	C15—H15B	0.9600

C1—S1—C4	90.57 (9)	C10—C9—C8	120.74 (18)
C13—O2—C14	115.51 (15)	C10—C9—H9	119.6
C12—O3—C15	117.37 (17)	C8—C9—H9	119.6
C2—C1—S1	113.76 (14)	C9—C10—C11	120.79 (18)
C2—C1—Cl1	126.07 (15)	C9—C10—H10	119.6
S1—C1—Cl1	120.16 (11)	C11—C10—H10	119.6
C1—C2—C3	111.04 (17)	C12—C11—C10	119.92 (19)
C1—C2—H2	124.5	C12—C11—H11	120.0
C3—C2—H2	124.5	C10—C11—H11	120.0
C4—C3—C2	113.79 (17)	O3—C12—C11	124.53 (17)
C4—C3—H3	123.1	O3—C12—C13	115.79 (16)
C2—C3—H3	123.1	C11—C12—C13	119.67 (17)
C3—C4—C5	131.18 (17)	O2—C13—C8	119.14 (16)
C3—C4—S1	110.84 (14)	O2—C13—C12	120.23 (16)
C5—C4—S1	117.97 (13)	C8—C13—C12	120.53 (17)
O1—C5—C4	119.86 (17)	O2—C14—H14C	109.5
O1—C5—C6	122.29 (18)	O2—C14—H14B	109.5
C4—C5—C6	117.85 (16)	H14C—C14—H14B	109.5
C7—C6—C5	121.68 (17)	O2—C14—H14A	109.5
C7—C6—H6	119.2	H14C—C14—H14A	109.5
C5—C6—H6	119.2	H14B—C14—H14A	109.5
C6—C7—C8	127.37 (18)	O3—C15—H15C	109.5
C6—C7—H7	116.3	O3—C15—H15A	109.5
C8—C7—H7	116.3	H15C—C15—H15A	109.5
C13—C8—C9	118.32 (17)	O3—C15—H15B	109.5
C13—C8—C7	119.08 (16)	H15C—C15—H15B	109.5
C9—C8—C7	122.57 (17)	H15A—C15—H15B	109.5

C4—S1—C1—C2	0.09 (17)	C13—C8—C9—C10	0.6 (3)
C4—S1—C1—Cl1	179.16 (12)	C7—C8—C9—C10	−177.48 (18)
S1—C1—C2—C3	−0.1 (2)	C8—C9—C10—C11	0.5 (3)
Cl1—C1—C2—C3	−179.14 (15)	C9—C10—C11—C12	−0.8 (3)
C1—C2—C3—C4	0.1 (3)	C15—O3—C12—C11	−3.8 (3)
C2—C3—C4—C5	−178.76 (19)	C15—O3—C12—C13	177.16 (18)
C2—C3—C4—S1	−0.1 (2)	C10—C11—C12—O3	−179.22 (18)
C1—S1—C4—C3	−0.02 (15)	C10—C11—C12—C13	−0.2 (3)
C1—S1—C4—C5	178.87 (15)	C14—O2—C13—C8	109.94 (19)
C3—C4—C5—O1	176.0 (2)	C14—O2—C13—C12	−73.6 (2)
S1—C4—C5—O1	−2.6 (2)	C9—C8—C13—O2	174.84 (15)
C3—C4—C5—C6	−4.6 (3)	C7—C8—C13—O2	−7.0 (2)
S1—C4—C5—C6	176.79 (13)	C9—C8—C13—C12	−1.6 (3)
O1—C5—C6—C7	−9.3 (3)	C7—C8—C13—C12	176.61 (16)
C4—C5—C6—C7	171.31 (17)	O3—C12—C13—O2	4.1 (3)
C5—C6—C7—C8	176.47 (17)	C11—C12—C13—O2	−175.02 (16)
C6—C7—C8—C13	175.42 (18)	O3—C12—C13—C8	−179.52 (16)
C6—C7—C8—C9	−6.5 (3)	C11—C12—C13—C8	1.4 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O1ⁱ	0.93	2.53	3.209 (2)	130
C15—H15A···O2ⁱⁱ	0.96	2.55	3.423 (3)	151

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

Experimental details

Crystal data
Chemical formula	C₁₅H₁₃ClO₃S
M_r	308.76
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	11.6139 (8), 8.5605 (5), 14.4174 (9)
β (°)	99.907 (2)
V (Å³)	1412.02 (16)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.42
Crystal size (mm)	0.20 × 0.18 × 0.16

Data collection
Diffractometer	Bruker SMART APEX CCD detector
Absorption correction	Multi-scan (SADABS; Bruker, 1998)
T_min, T_max	0.920, 0.936
No. of measured, independent and observed [I > 2σ(I)] reflections	9286, 3087, 2348
R_int	0.026
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.038, 0.102, 1.07
No. of reflections	3087
No. of parameters	183
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.21, −0.26

Computer programs: SMART (Bruker, 1998), SAINT-Plus (Bruker, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and CAMERON (Watkin et al., 1996), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O1ⁱ	0.93	2.528	3.209 (2)	130
C15—H15A···O2ⁱⁱ	0.96	2.549	3.423 (3)	151

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

Acknowledgements

ANP is thankful to Manipal Institute of Technology, Manipal University.

References

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