4-(5-tert-Butyl-1,3-dithian-2-yl)-5-chloro-2-phenyl-1,3-oxazole

Cui, Y.; Liu, L.; Liu, M.; Duan, Y.; Liu, S.

doi:10.1107/S1600536808002821

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 64| Part 3| March 2008| Page o543

doi:10.1107/S1600536808002821

Open

access

4-(5-tert-Butyl-1,3-dithian-2-yl)-5-chloro-2-phenyl-1,3-oxazole

Yongliang Cui,^a Lei Liu,^a Ming Liu,^a Yousheng Duan ^a and Shangzhong Liu ^a ^*

^aDepartment of Applied Chemistry, China Agriculture University, 100094 Beijing, People's Republic of China
^*Correspondence e-mail: shangzho@cau.edu.cn

(Received 7 January 2008; accepted 25 January 2008; online 6 February 2008)

In the title molecule, C₁₇H₂₀ClNOS₂, the phenyl and oxazole rings are nearly coplanar with an average deviation of 0.022 Å from the mean plane (M). The 1,3-dithiane ring adopts a chair conformation and is twisted in such a way that the C—C_Bu fragment lies in M (deviations are 0.031 and 0.010 Å, respectively, for the two C atoms).

Related literature

For details of the pharmacological properties of the GABA [GABA = γ-aminobutyric acid] receptor, see: Wacher et al. (1992 ). For the related structural series of the GABA receptor, see: Jeffrey (2003 ); Naratashi et al. (2007 ).

Experimental

Crystal data

C₁₇H₂₀ClNOS₂
M_r = 353.91
Monoclinic, P 2₁ /c
a = 7.4543 (15) Å
b = 26.222 (5) Å
c = 9.4772 (19) Å
β = 104.59 (3)°
V = 1792.7 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.45 mm⁻¹
T = 296 (2) K
0.34 × 0.31 × 0.18 mm

Data collection

Rigaku R-AXIS RAPID IP area-detector diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ) T_min = 0.863, T_max = 0.924
5683 measured reflections
3135 independent reflections
2788 reflections with I > 2σ(I)
R_int = 0.023

Refinement

R[F² > 2σ(F²)] = 0.050
wR(F²) = 0.130
S = 1.10
3135 reflections
199 parameters
59 restraints
H-atom parameters constrained
Δρ_max = 0.37 e Å⁻³
Δρ_min = −0.23 e Å⁻³

Data collection: RAPID-AUTO (Rigaku, 2001 ); cell refinement: RAPID-AUTO; data reduction: RAPID-AUTO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in Siemens SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808002821/cv2381sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808002821/cv2381Isup2.hkl

checkCIF report

Comment top

γ-Aminobutyric acid (GABA) receptor of insect exists in their nerve cell and intramuscular cell, and a combinative site of many insecticide and active compounds (Wacher et al., 1992). A large number of related structural series (e.g., trioxabicyclooctanes, thiazines, arylpyrimidines, oxathianes, and dithianes) was synthesized and assayed on GABA receptor to discover novel insecticides (Jeffrey, 2003). Until now, only synthetic compound Fipronil is broadly used to control certain species of insects that have become resistant to most insecticides (Naratashi et al., 2007). In order to further optimize 1,3-dithiane derivative, the title compound, (I), was synthesized. Herewith we present its crystal structure.

In the title molecule, the phenyl and oxazole rings are nearly coplanar with the average deviation of 0.022 Å from the mean plane (M). The 1,3-dithiane ring adopts a chair conformation being twisted in such a way, that two-atomic fragment C12—C14 actually lie in M with deviations of 0.031 and 0.010 Å, respectively. The crystal structure exhibits no classical hydrogen bonds.

Related literature top

For details of the pharmacological properties of the GABA receptor, see: Wacher et al. (1992). For the related structural series of the GABA receptor, see: Jeffrey (2003); Naratashi et al. (2007). [Title molecule is a GABA receptor?]

Experimental top

Compound (I) was prepared by the 4 h reaction of 0.8 g (3.85 mmol) of 5-chloro-2-phenyloxazole-4-carbaldehyde and 0.8 g (4.88 mmol) of 2-tert-butylpropane-1,3-dithiol in the presence of two drops formic acid used as a catalyst at room temperature with stirring. The resulting mixture was dissolved in chloroform (60 ml), washed with aqueous 10% NaOH (3×20 ml) and H₂O (3×20 ml), and then dried with anhydrous sodium sulfate. After concentration, the residue was purified by re-crystallization in a mixed solvent of ethyl acetate and petroleum ether. Single crystals suitable for X-ray data collection were obtained by re-crystallization of the crude product from a mixed solvent ethyl acetate and petroleum ether (v/v, 1/20) as a light yellow crystalline solid (60%), m.p. 453 K.

Computing details top

Data collection: RAPID-AUTO (Rigaku, 2001); cell refinement: RAPID-AUTO (Rigaku, 2001); data reduction: RAPID-AUTO (Rigaku, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in Siemens SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of (I), with atomic labels and 30% probability displacement ellipsoids for non-H atoms.

4-(5-tert-Butyl-1,3-dithian-2-yl)-5-chloro-2-phenyl-1,3-oxazole ? top

Crystal data top

C₁₇H₂₀ClNOS₂	F(000) = 744
M_r = 353.91	D_x = 1.311 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 7.4543 (15) Å	Cell parameters from 13320 reflections
b = 26.222 (5) Å	θ = 2.2–27.5°
c = 9.4772 (19) Å	µ = 0.45 mm⁻¹
β = 104.59 (3)°	T = 296 K
V = 1792.7 (6) Å³	Plate, colourless
Z = 4	0.34 × 0.31 × 0.18 mm

Data collection top

Rigaku R-AXIS RAPID IP area-detector diffractometer	3135 independent reflections
Radiation source: rotating anode	2788 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.023
ω scans at fixed χ = 45°	θ_max = 25.0°, θ_min = 2.7°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −8→8
T_min = 0.863, T_max = 0.924	k = −30→31
5683 measured reflections	l = −11→11

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)] = 0.050	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.130	H-atom parameters constrained
S = 1.10	w = 1/[σ²(F_o²) + (0.0651P)² + 0.55P] where P = (F_o² + 2F_c²)/3
3135 reflections	(Δ/σ)_max = 0.001
199 parameters	Δρ_max = 0.37 e Å⁻³
59 restraints	Δρ_min = −0.23 e Å⁻³

Crystal data top

C₁₇H₂₀ClNOS₂	V = 1792.7 (6) Å³
M_r = 353.91	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 7.4543 (15) Å	µ = 0.45 mm⁻¹
b = 26.222 (5) Å	T = 296 K
c = 9.4772 (19) Å	0.34 × 0.31 × 0.18 mm
β = 104.59 (3)°

Data collection top

Rigaku R-AXIS RAPID IP area-detector diffractometer	3135 independent reflections
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	2788 reflections with I > 2σ(I)
T_min = 0.863, T_max = 0.924	R_int = 0.023
5683 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.050	59 restraints
wR(F²) = 0.130	H-atom parameters constrained
S = 1.10	Δρ_max = 0.37 e Å⁻³
3135 reflections	Δρ_min = −0.23 e Å⁻³
199 parameters

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'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 > σ(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	0.21531 (9)	0.68715 (2)	0.75838 (9)	0.0672 (2)
S2	0.56576 (9)	0.74615 (2)	0.89160 (8)	0.0656 (2)
Cl1	0.74022 (11)	0.62257 (3)	0.61190 (8)	0.0840 (3)
O1	0.7196 (2)	0.57469 (6)	0.84876 (18)	0.0576 (4)
N1	0.5427 (3)	0.62247 (7)	0.9549 (2)	0.0541 (5)
C1	0.6072 (4)	0.54919 (11)	1.1975 (3)	0.0732 (7)
H1B	0.5353	0.5776	1.2042	0.088*
C2	0.6441 (5)	0.51328 (13)	1.3080 (4)	0.0923 (10)
H2A	0.5966	0.5174	1.3891	0.111*
C3	0.7516 (6)	0.47136 (13)	1.2970 (4)	0.0978 (11)
H3A	0.7789	0.4476	1.3723	0.117*
C4	0.8183 (5)	0.46438 (12)	1.1775 (4)	0.0869 (9)
H4A	0.8881	0.4355	1.1703	0.104*
C5	0.7828 (4)	0.49976 (10)	1.0678 (3)	0.0685 (7)
H5A	0.8293	0.4950	0.9865	0.082*
C6	0.6776 (3)	0.54266 (9)	1.0775 (3)	0.0557 (6)
C7	0.6401 (3)	0.58120 (9)	0.9633 (3)	0.0530 (5)
C8	0.6628 (3)	0.61672 (10)	0.7651 (3)	0.0567 (6)
C9	0.5551 (3)	0.64573 (9)	0.8256 (2)	0.0523 (5)
C10	0.4602 (3)	0.69455 (9)	0.7721 (3)	0.0523 (5)
H10A	0.4767	0.7014	0.6744	0.063*
C11	0.1332 (4)	0.75009 (9)	0.6948 (3)	0.0619 (6)
H11A	0.1585	0.7558	0.6006	0.074*
H11B	−0.0002	0.7511	0.6810	0.074*
C12	0.2190 (3)	0.79347 (9)	0.7963 (2)	0.0490 (5)
H12A	0.2133	0.7835	0.8948	0.059*
C13	0.4239 (3)	0.79820 (9)	0.7989 (3)	0.0598 (6)
H13A	0.4711	0.8300	0.8465	0.072*
H13B	0.4354	0.7999	0.6993	0.072*
C14	0.1074 (4)	0.84396 (9)	0.7598 (3)	0.0573 (6)
C15	−0.0878 (4)	0.83563 (13)	0.7799 (4)	0.0839 (9)
H15A	−0.1582	0.8665	0.7568	0.126*
H15B	−0.0799	0.8263	0.8793	0.126*
H15C	−0.1478	0.8088	0.7163	0.126*
C16	0.0952 (4)	0.86200 (12)	0.6043 (3)	0.0718 (8)
H16A	0.0248	0.8930	0.5861	0.108*
H16B	0.0353	0.8363	0.5365	0.108*
H16C	0.2177	0.8680	0.5927	0.108*
C17	0.2000 (5)	0.88590 (11)	0.8662 (4)	0.0872 (9)
H17A	0.1309	0.9170	0.8433	0.131*
H17B	0.3244	0.8912	0.8580	0.131*
H17C	0.2026	0.8758	0.9641	0.131*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0550 (4)	0.0493 (4)	0.0934 (5)	−0.0030 (3)	0.0113 (3)	−0.0006 (3)
S2	0.0556 (4)	0.0521 (4)	0.0797 (5)	−0.0014 (3)	−0.0003 (3)	0.0031 (3)
Cl1	0.0849 (5)	0.1090 (6)	0.0667 (4)	0.0281 (4)	0.0352 (4)	0.0140 (4)
O1	0.0560 (9)	0.0558 (10)	0.0616 (9)	0.0092 (7)	0.0160 (8)	−0.0001 (8)
N1	0.0581 (11)	0.0478 (11)	0.0585 (11)	0.0033 (9)	0.0184 (9)	0.0039 (9)
C1	0.089 (2)	0.0544 (15)	0.0798 (18)	−0.0037 (14)	0.0279 (15)	0.0077 (13)
C2	0.127 (3)	0.077 (2)	0.078 (2)	−0.0156 (19)	0.0358 (19)	0.0161 (16)
C3	0.120 (3)	0.066 (2)	0.095 (2)	−0.0088 (19)	0.004 (2)	0.0311 (18)
C4	0.089 (2)	0.0623 (18)	0.103 (2)	0.0064 (16)	0.0135 (18)	0.0195 (17)
C5	0.0613 (15)	0.0566 (15)	0.0855 (18)	0.0035 (12)	0.0146 (13)	0.0100 (13)
C6	0.0536 (13)	0.0455 (12)	0.0659 (14)	−0.0071 (10)	0.0112 (11)	0.0033 (11)
C7	0.0498 (12)	0.0492 (13)	0.0595 (13)	−0.0037 (10)	0.0128 (10)	0.0019 (10)
C8	0.0568 (14)	0.0595 (15)	0.0539 (13)	0.0065 (11)	0.0144 (11)	0.0032 (11)
C9	0.0535 (13)	0.0508 (13)	0.0535 (12)	0.0025 (10)	0.0152 (10)	0.0020 (10)
C10	0.0563 (13)	0.0508 (13)	0.0518 (12)	0.0038 (10)	0.0174 (10)	0.0038 (10)
C11	0.0567 (14)	0.0566 (15)	0.0679 (16)	0.0077 (11)	0.0074 (12)	−0.0025 (12)
C12	0.0570 (13)	0.0518 (12)	0.0415 (11)	0.0058 (10)	0.0185 (9)	0.0037 (9)
C13	0.0595 (14)	0.0468 (13)	0.0719 (16)	−0.0006 (11)	0.0145 (12)	0.0041 (12)
C14	0.0698 (15)	0.0535 (14)	0.0535 (13)	0.0113 (11)	0.0246 (11)	0.0070 (10)
C15	0.0820 (19)	0.082 (2)	0.103 (2)	0.0264 (16)	0.0518 (18)	0.0230 (18)
C16	0.0836 (19)	0.0727 (18)	0.0630 (15)	0.0201 (15)	0.0259 (14)	0.0213 (13)
C17	0.119 (3)	0.0591 (17)	0.0819 (19)	0.0193 (17)	0.0230 (18)	−0.0095 (14)

Geometric parameters (Å, º) top

S1—C10	1.808 (3)	C9—C10	1.489 (3)
S1—C11	1.810 (3)	C10—H10A	0.9800
S2—C10	1.812 (2)	C11—C12	1.523 (3)
S2—C13	1.813 (3)	C11—H11A	0.9700
Cl1—C8	1.699 (3)	C11—H11B	0.9700
O1—C8	1.362 (3)	C12—C13	1.526 (3)
O1—C7	1.372 (3)	C12—C14	1.556 (3)
N1—C7	1.294 (3)	C12—H12A	0.9800
N1—C9	1.393 (3)	C13—H13A	0.9700
C1—C6	1.378 (4)	C13—H13B	0.9700
C1—C2	1.383 (4)	C14—C16	1.528 (3)
C1—H1B	0.9300	C14—C15	1.530 (4)
C2—C3	1.380 (5)	C14—C17	1.534 (4)
C2—H2A	0.9300	C15—H15A	0.9600
C3—C4	1.359 (5)	C15—H15B	0.9600
C3—H3A	0.9300	C15—H15C	0.9600
C4—C5	1.369 (4)	C16—H16A	0.9600
C4—H4A	0.9300	C16—H16B	0.9600
C5—C6	1.387 (4)	C16—H16C	0.9600
C5—H5A	0.9300	C17—H17A	0.9600
C6—C7	1.455 (3)	C17—H17B	0.9600
C8—C9	1.335 (3)	C17—H17C	0.9600

C10—S1—C11	100.18 (12)	C12—C11—H11B	108.6
C10—S2—C13	98.67 (12)	S1—C11—H11B	108.6
C8—O1—C7	103.14 (18)	H11A—C11—H11B	107.6
C7—N1—C9	105.1 (2)	C11—C12—C13	109.28 (19)
C6—C1—C2	119.7 (3)	C11—C12—C14	112.3 (2)
C6—C1—H1B	120.1	C13—C12—C14	114.3 (2)
C2—C1—H1B	120.1	C11—C12—H12A	106.9
C3—C2—C1	119.6 (3)	C13—C12—H12A	106.9
C3—C2—H2A	120.2	C14—C12—H12A	106.9
C1—C2—H2A	120.2	C12—C13—S2	113.93 (17)
C4—C3—C2	120.8 (3)	C12—C13—H13A	108.8
C4—C3—H3A	119.6	S2—C13—H13A	108.8
C2—C3—H3A	119.6	C12—C13—H13B	108.8
C3—C4—C5	120.0 (3)	S2—C13—H13B	108.8
C3—C4—H4A	120.0	H13A—C13—H13B	107.7
C5—C4—H4A	120.0	C16—C14—C15	109.7 (2)
C4—C5—C6	120.2 (3)	C16—C14—C17	108.7 (2)
C4—C5—H5A	119.9	C15—C14—C17	107.7 (2)
C6—C5—H5A	119.9	C16—C14—C12	112.15 (19)
C1—C6—C5	119.6 (3)	C15—C14—C12	108.8 (2)
C1—C6—C7	119.0 (2)	C17—C14—C12	109.7 (2)
C5—C6—C7	121.3 (2)	C14—C15—H15A	109.5
N1—C7—O1	113.7 (2)	C14—C15—H15B	109.5
N1—C7—C6	128.8 (2)	H15A—C15—H15B	109.5
O1—C7—C6	117.5 (2)	C14—C15—H15C	109.5
C9—C8—O1	110.1 (2)	H15A—C15—H15C	109.5
C9—C8—Cl1	133.3 (2)	H15B—C15—H15C	109.5
O1—C8—Cl1	116.62 (18)	C14—C16—H16A	109.5
C8—C9—N1	108.0 (2)	C14—C16—H16B	109.5
C8—C9—C10	129.0 (2)	H16A—C16—H16B	109.5
N1—C9—C10	123.0 (2)	C14—C16—H16C	109.5
C9—C10—S1	108.47 (16)	H16A—C16—H16C	109.5
C9—C10—S2	109.57 (17)	H16B—C16—H16C	109.5
S1—C10—S2	113.36 (13)	C14—C17—H17A	109.5
C9—C10—H10A	108.4	C14—C17—H17B	109.5
S1—C10—H10A	108.4	H17A—C17—H17B	109.5
S2—C10—H10A	108.4	C14—C17—H17C	109.5
C12—C11—S1	114.70 (17)	H17A—C17—H17C	109.5
C12—C11—H11A	108.6	H17B—C17—H17C	109.5
S1—C11—H11A	108.6

C6—C1—C2—C3	0.3 (5)	C7—N1—C9—C8	−0.8 (3)
C1—C2—C3—C4	−1.5 (6)	C7—N1—C9—C10	179.2 (2)
C2—C3—C4—C5	1.6 (6)	C8—C9—C10—S1	124.2 (3)
C3—C4—C5—C6	−0.5 (5)	N1—C9—C10—S1	−55.9 (3)
C2—C1—C6—C5	0.8 (4)	C8—C9—C10—S2	−111.6 (3)
C2—C1—C6—C7	−179.0 (3)	N1—C9—C10—S2	68.4 (3)
C4—C5—C6—C1	−0.7 (4)	C11—S1—C10—C9	179.42 (16)
C4—C5—C6—C7	179.1 (3)	C11—S1—C10—S2	57.48 (16)
C9—N1—C7—O1	0.4 (3)	C13—S2—C10—C9	179.80 (17)
C9—N1—C7—C6	178.9 (2)	C13—S2—C10—S1	−58.88 (15)
C8—O1—C7—N1	0.2 (3)	C10—S1—C11—C12	−59.4 (2)
C8—O1—C7—C6	−178.5 (2)	S1—C11—C12—C13	67.9 (2)
C1—C6—C7—N1	−1.5 (4)	S1—C11—C12—C14	−164.19 (16)
C5—C6—C7—N1	178.6 (2)	C11—C12—C13—S2	−70.4 (2)
C1—C6—C7—O1	177.0 (2)	C14—C12—C13—S2	162.84 (16)
C5—C6—C7—O1	−2.9 (3)	C10—S2—C13—C12	63.2 (2)
C7—O1—C8—C9	−0.7 (3)	C11—C12—C14—C16	−59.6 (3)
C7—O1—C8—Cl1	178.63 (17)	C13—C12—C14—C16	65.6 (3)
O1—C8—C9—N1	1.0 (3)	C11—C12—C14—C15	62.0 (3)
Cl1—C8—C9—N1	−178.2 (2)	C13—C12—C14—C15	−172.8 (2)
O1—C8—C9—C10	−179.1 (2)	C11—C12—C14—C17	179.6 (2)
Cl1—C8—C9—C10	1.8 (4)	C13—C12—C14—C17	−55.2 (3)

Experimental details

Crystal data
Chemical formula	C₁₇H₂₀ClNOS₂
M_r	353.91
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	7.4543 (15), 26.222 (5), 9.4772 (19)
β (°)	104.59 (3)
V (Å³)	1792.7 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.45
Crystal size (mm)	0.34 × 0.31 × 0.18

Data collection
Diffractometer	Rigaku R-AXIS RAPID IP area-detector diffractometer
Absorption correction	Multi-scan (ABSCOR; Higashi, 1995)
T_min, T_max	0.863, 0.924
No. of measured, independent and observed [I > 2σ(I)] reflections	5683, 3135, 2788
R_int	0.023
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.050, 0.130, 1.10
No. of reflections	3135
No. of parameters	199
No. of restraints	59
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.37, −0.23

Computer programs: RAPID-AUTO (Rigaku, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in Siemens SHELXTL (Sheldrick, 2008).

Acknowledgements

This work was supported by the National Natural Science Foundation of China (NNSFC) (grant No. 20572129), the National Basic Research Program of China (grant No. 2003CB114405) and the National Key Project of Scientific and Technical Supporting Programs funded by the Ministry of Science and Technology of China (grant No. 2006BAE01AE01-11).

References

Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan. Google Scholar
Jeffrey, R. B. (2003). Arch. Insect Biochem. Physiol. 54, 145–156. Web of Science PubMed Google Scholar
Naratashi, T., Zhao, X., Ikeda, T., Nagata, K. & Yeh, J. Z. (2007). Hum. Exp. Toxicol. 26, 361–366. Web of Science PubMed Google Scholar
Rigaku (2001). RAPID-AUTO. Rigaku Corporation, Tokyo, Japan. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Wacher, V. J., Toia, R. F. & Casida, J. E. (1992). J. Agric. Food. Chem. 40, 497–505. CrossRef CAS Web of Science Google Scholar