1,4-Bis[2-(1,3-benzothia­zol-2-yl)phen­oxy]butane

Büyükgüngör, O.; Özek, A.; Karahan, S.; Subaşı, E.

doi:10.1107/S1600536808002705

organic compounds

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ISSN: 2056-9890

Volume 64| Part 2| February 2008| Page o528

doi:10.1107/S1600536808002705

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1,4-Bis[2-(1,3-benzothiazol-2-yl)phenoxy]butane

Orhan Büyükgüngör,^a ^* Arzu Özek,^a Senem Karahan ^b and Elif Subaşı ^b

^aDepartment of Physics, Ondokuz Mayıs University, TR-55139 Samsun, Turkey, and ^bDepartment of Physics, Dokuz Eylül University, İzmir, Turkey
^*Correspondence e-mail: orhanb@omu.edu.tr

(Received 23 January 2008; accepted 24 January 2008; online 30 January 2008)

The molecule of the title compound, C₃₀H₂₄N₂O₂S₂, adopts a transoid conformation consistent with the inversion centre located at the mid-point of the central C—C single bond, resulting in one half molecule in the asymmetric unit. The dihedral angle between the coplanar benzothiazole ring system and the benzene ring is 11.06 (7)°. In the crystal structure, molecules are linked by weak intermolecular π–π interactions between thiazole and benzene rings to form a three-dimensional network.

Related literature

For general background, see: Delmas et al. (2002 ); Karalı et al. (2004 ); Weinstock et al. (1987 ); Chopade et al. (2002 ); Di Nunno et al. (2000 ); Gökhan et al. (2004 ). For related structures, see: Sieroń et al. (1999 ); Usman et al. (2003 ). For related literature, see: Temel et al. (2008 ).

Experimental

Crystal data

C₃₀H₂₄N₂O₂S₂
M_r = 508.63
Monoclinic, P 2₁ /c
a = 14.3251 (13) Å
b = 4.8992 (3) Å
c = 17.4954 (17) Å
β = 102.522 (7)°
V = 1198.65 (18) Å³
Z = 2
Mo Kα radiation
μ = 0.26 mm⁻¹
T = 296 K
0.80 × 0.36 × 0.08 mm

Data collection

Stoe IPDSII diffractometer
Absorption correction: integration (X-RED32; Stoe & Cie, 2002 ) T_min = 0.442, T_max = 0.936
14397 measured reflections
2339 independent reflections
1456 reflections with I > 2σ(I)
R_int = 0.075

Refinement

R[F² > 2σ(F²)] = 0.034
wR(F²) = 0.069
S = 0.84
2339 reflections
163 parameters
H-atom parameters constrained
Δρ_max = 0.14 e Å⁻³
Δρ_min = −0.19 e Å⁻³

Table 1
The observed π–π interaction distances (Å) for the title compound.

Cg—Cgⁱ	d_centroids	d_{perpendicular}
Cg1—Cg2ⁱ	3.775 (11)	3.515
Cg1—Cg3ⁱ	3.7934 (12)	3.59
Cg1, Cg2 and Cg3 are the centroids of atoms S1/N1/C1/C6/C7, (C1–C6) and (C8–C13) rings, respectively. Symmetry code: (i) x, 1+y, z.

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808002705/hk2423sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808002705/hk2423Isup2.hkl

checkCIF report

Comment top

Benzothiazole derivatives possess a broad spectrum of pharmacological activity, including antibacterial, antifungal (Delmas et al., 2002; Karalı et al., 2004), dopaminergic (Weinstock et al., 1987), anticonvulsant (Chopade et al., 2002), antiadrenergic (Di Nunno et al., 2000) and analgesic anti-inflammatory activities (Gökhan et al., 2004). We report herein the synthesis and structure of the title compound, (I), which is a new benzothiazole derivative.

The molecule of the title compound, (I), (Fig. 1) displays an inversion centre with a half molecule in the asymmetric unit. The benzene ring and its fused thiazole ring are nearly coplanar, with the maximum deviation from the least-squares plane through S1/N1/C1—C7 occurring at S1 [0.033 (9) Å]. However, the molecule itself is nonplanar; the dihedral angle between the coplanar benzothiazole ring system and benzene ring is 11.06 (7)°. The N1—C7 [1.299 (2) Å] bond indicates double-bond character, whereas the S—C bond lengths are indicative of significant single-bond character. The S1—C1 [1.7231 (19) Å] bond is shorter than S1—C7 [1.7552 (18) Å], due to the fact that C7 is sp² hybridized, whereas C1 is part of the aromatic ring. A similar effect was observed for cis-bis(2-amino-1,3-benzothiazole-N³)bis- (formato-O,O')copper(II) [(II); Sieroń et al., 1999] and diacetatobis- (2-aminobenzothiazole)zinc(II) [(III); Usman et al., 2003]. The corresponding N—C and S—C values are [N1—C2 = 1.321 (3) Å, S1—C2 = 1.742 (3) Å and S1—C8 = 1.741 (3) Å, in (II)] and [N1—C1 = 1.311 (3) Å, N3—C8 = 1.317 (3) Å, S1—C1 = 1.747 (2) Å, S1—C2 = 1.733 (3) Å, S2—C8 = 1.751 (2) Å and S2—C9 = 1.749 (3) Å, in (III)].

In the crystal structure, the molecules are linked by weak intermolecular π···π interactions (Table 1) between thiazole and benzene rings to form a three-dimensional network (Fig. 2).

Related literature top

For general background, see: Delmas et al. (2002); Karalı et al. (2004); Weinstock et al. (1987); Chopade et al. (2002); Di Nunno et al. (2000); Gökhan et al. (2004). For related structures, see: Sieroń et al. (1999); Usman et al. (2003). For related literature, see: Temel et al. (2008).

Experimental top

The title compound, (I), was prepared by the literature method (Temel et al., 2008). It was obtained from the photochemical reaction of M(CO)₅ THF (M= Cr) (132 mg, 0.5 mmol) with N,N'-bis(2-aminothiophenol)-1,4-bis(2-carboxaldehyde- phenoxy) butane (153 mg, 0.3 mmol) in THF for 2 h at room temperature. UV irradiation was performed with a medium-pressure (125 W) mercury lamp through a quartz-walled immersion well reactor, which was cooled by circulating water. After the photochemical reaction, the solvent was removed under vacuum afford a solid residue which was dissolved in CH₂Cl₂ and then petroleum ether was added for the purification process. The solution was allowed to cool in a deep-freezer. Small colorless crystals grown in the CH₂Cl₂ /petroleum ether solution were filtered off and finally dried.

Computing details top

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA (Stoe & Cie, 2002); data reduction: X-RED32 (Stoe & Cie, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. A view of (I) with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level [symmetry code: (i) -x, -y, -z].
	Fig. 2. A partial packing diagram of (I), showing the π···π bonds (drawn as dashed lines) [symmetry code: (i) x, 1 + y, z].

1,4-Bis[2-(1,3-benzothiazol-2-yl)phenoxy]butane top

Crystal data top

C₃₀H₂₄N₂O₂S₂	F(000) = 532
M_r = 508.63	D_x = 1.409 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 14397 reflections
a = 14.3251 (13) Å	θ = 1.7–28.0°
b = 4.8992 (3) Å	µ = 0.26 mm⁻¹
c = 17.4954 (17) Å	T = 296 K
β = 102.522 (7)°	Thin long plate, colorless
V = 1198.65 (18) Å³	0.80 × 0.36 × 0.08 mm
Z = 2

Data collection top

Stoe IPDSII diffractometer	2339 independent reflections
Radiation source: fine-focus sealed tube	1456 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.075
Detector resolution: 6.67 pixels mm^-1	θ_max = 26.0°, θ_min = 2.4°
ω scans	h = −16→17
Absorption correction: integration (X-RED32; Stoe & Cie, 2002)	k = −6→6
T_min = 0.442, T_max = 0.936	l = −21→21
14397 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)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.069	H-atom parameters constrained
S = 0.84	w = 1/[σ²(F_o²) + (0.0302P)²] where P = (F_o² + 2F_c²)/3
2339 reflections	(Δ/σ)_max = 0.001
163 parameters	Δρ_max = 0.14 e Å⁻³
0 restraints	Δρ_min = −0.19 e Å⁻³

Crystal data top

C₃₀H₂₄N₂O₂S₂	V = 1198.65 (18) Å³
M_r = 508.63	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 14.3251 (13) Å	µ = 0.26 mm⁻¹
b = 4.8992 (3) Å	T = 296 K
c = 17.4954 (17) Å	0.80 × 0.36 × 0.08 mm
β = 102.522 (7)°

Data collection top

Stoe IPDSII diffractometer	2339 independent reflections
Absorption correction: integration (X-RED32; Stoe & Cie, 2002)	1456 reflections with I > 2σ(I)
T_min = 0.442, T_max = 0.936	R_int = 0.075
14397 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.034	0 restraints
wR(F²) = 0.069	H-atom parameters constrained
S = 0.84	Δρ_max = 0.14 e Å⁻³
2339 reflections	Δρ_min = −0.19 e Å⁻³
163 parameters

Special details top

Experimental. 322 frames, detector distance = 100 mm

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	0.15719 (4)	0.95193 (10)	0.66141 (3)	0.05013 (15)
O1	0.18060 (9)	0.6078 (3)	0.54404 (7)	0.0548 (4)
N1	0.33188 (11)	1.0657 (3)	0.72790 (8)	0.0474 (4)
C1	0.17643 (14)	1.1896 (4)	0.73578 (10)	0.0449 (5)
C2	0.11011 (15)	1.3333 (4)	0.76826 (11)	0.0558 (5)
H2	0.0448	1.3057	0.7506	0.067*
C3	0.14437 (17)	1.5159 (4)	0.82685 (12)	0.0610 (6)
H3	0.1015	1.6124	0.8495	0.073*
C4	0.24200 (17)	1.5602 (4)	0.85322 (11)	0.0593 (5)
H4	0.2634	1.6883	0.8923	0.071*
C5	0.30670 (15)	1.4168 (4)	0.82207 (11)	0.0546 (5)
H5	0.3719	1.4453	0.8402	0.066*
C6	0.27417 (14)	1.2284 (4)	0.76311 (10)	0.0454 (5)
C7	0.28134 (13)	0.9108 (4)	0.67424 (10)	0.0420 (4)
C8	0.32640 (13)	0.7109 (4)	0.63100 (10)	0.0421 (4)
C9	0.42400 (14)	0.6654 (4)	0.65603 (11)	0.0524 (5)
H9	0.4582	0.7634	0.6985	0.063*
C10	0.47127 (14)	0.4785 (4)	0.61944 (12)	0.0596 (6)
H10	0.5365	0.4496	0.6375	0.071*
C11	0.42174 (16)	0.3352 (4)	0.55621 (12)	0.0599 (6)
H11	0.4537	0.2111	0.5308	0.072*
C12	0.32498 (16)	0.3741 (4)	0.53009 (11)	0.0545 (5)
H12	0.2917	0.2754	0.4874	0.065*
C13	0.27700 (13)	0.5594 (4)	0.56711 (10)	0.0453 (4)
C14	0.12712 (14)	0.4466 (4)	0.48140 (10)	0.0518 (5)
H14A	0.1321	0.2546	0.4953	0.062*
H14B	0.1517	0.4722	0.4344	0.062*
C15	0.02453 (14)	0.5376 (4)	0.46736 (11)	0.0556 (5)
H15A	−0.0104	0.4565	0.4190	0.067*
H15B	0.0221	0.7342	0.4607	0.067*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0431 (3)	0.0516 (3)	0.0532 (3)	−0.0016 (3)	0.0050 (2)	−0.0062 (2)
O1	0.0427 (8)	0.0624 (9)	0.0539 (8)	0.0000 (6)	−0.0010 (6)	−0.0175 (7)
N1	0.0471 (10)	0.0445 (9)	0.0480 (9)	−0.0022 (8)	0.0044 (7)	−0.0040 (8)
C1	0.0494 (13)	0.0390 (11)	0.0462 (11)	−0.0003 (9)	0.0103 (9)	0.0044 (8)
C2	0.0520 (13)	0.0539 (13)	0.0614 (13)	0.0044 (10)	0.0122 (10)	−0.0004 (10)
C3	0.0730 (16)	0.0560 (14)	0.0575 (12)	0.0126 (11)	0.0215 (10)	−0.0008 (10)
C4	0.0809 (17)	0.0459 (11)	0.0496 (11)	0.0013 (12)	0.0104 (11)	−0.0067 (10)
C5	0.0599 (14)	0.0488 (12)	0.0516 (11)	−0.0042 (10)	0.0041 (9)	−0.0043 (10)
C6	0.0525 (13)	0.0387 (11)	0.0426 (10)	−0.0012 (9)	0.0053 (9)	0.0018 (8)
C7	0.0425 (11)	0.0426 (11)	0.0392 (9)	−0.0024 (9)	0.0053 (8)	0.0031 (8)
C8	0.0421 (12)	0.0410 (11)	0.0421 (10)	−0.0013 (9)	0.0065 (8)	0.0019 (8)
C9	0.0444 (12)	0.0537 (12)	0.0557 (12)	−0.0011 (10)	0.0034 (9)	−0.0036 (9)
C10	0.0443 (12)	0.0659 (15)	0.0670 (13)	0.0061 (11)	0.0087 (10)	−0.0047 (11)
C11	0.0583 (15)	0.0610 (14)	0.0635 (13)	0.0095 (11)	0.0197 (11)	−0.0063 (11)
C12	0.0565 (14)	0.0574 (13)	0.0483 (11)	−0.0001 (10)	0.0087 (9)	−0.0087 (9)
C13	0.0425 (12)	0.0474 (11)	0.0446 (10)	0.0007 (9)	0.0060 (8)	0.0021 (9)
C14	0.0518 (12)	0.0559 (12)	0.0440 (10)	−0.0085 (10)	0.0024 (8)	−0.0065 (9)
C15	0.0510 (13)	0.0652 (13)	0.0452 (11)	−0.0105 (10)	−0.0012 (8)	0.0023 (10)

Geometric parameters (Å, º) top

C1—S1	1.7231 (19)	C9—C10	1.376 (3)
C1—C2	1.398 (3)	C9—H9	0.9300
C1—C6	1.391 (3)	C10—C11	1.371 (3)
C2—C3	1.369 (3)	C10—H10	0.9300
C2—H2	0.9300	C11—C12	1.375 (3)
C3—C4	1.391 (3)	C11—H11	0.9300
C3—H3	0.9300	C12—C13	1.382 (3)
C4—C5	1.367 (3)	C12—H12	0.9300
C4—H4	0.9300	C13—O1	1.373 (2)
C5—C6	1.387 (3)	C14—O1	1.431 (2)
C5—H5	0.9300	C14—C15	1.504 (3)
C6—N1	1.385 (2)	C14—H14A	0.9700
C7—S1	1.7552 (18)	C14—H14B	0.9700
C7—N1	1.299 (2)	C15—C15ⁱ	1.511 (4)
C7—C8	1.469 (2)	C15—H15A	0.9700
C8—C9	1.390 (3)	C15—H15B	0.9700
C8—C13	1.399 (2)

C6—C1—C2	120.89 (18)	C11—C10—C9	119.68 (19)
C6—C1—S1	109.65 (14)	C11—C10—H10	120.2
C2—C1—S1	129.46 (16)	C9—C10—H10	120.2
C3—C2—C1	117.9 (2)	C10—C11—C12	120.33 (19)
C3—C2—H2	121.0	C10—C11—H11	119.8
C1—C2—H2	121.0	C12—C11—H11	119.8
C2—C3—C4	121.45 (19)	C11—C12—C13	120.22 (19)
C2—C3—H3	119.3	C11—C12—H12	119.9
C4—C3—H3	119.3	C13—C12—H12	119.9
C5—C4—C3	120.5 (2)	O1—C13—C12	123.13 (17)
C5—C4—H4	119.8	O1—C13—C8	116.46 (16)
C3—C4—H4	119.8	C12—C13—C8	120.41 (18)
C4—C5—C6	119.4 (2)	O1—C14—C15	107.66 (15)
C4—C5—H5	120.3	O1—C14—H14A	110.2
C6—C5—H5	120.3	C15—C14—H14A	110.2
N1—C6—C5	125.23 (18)	O1—C14—H14B	110.2
N1—C6—C1	114.94 (16)	C15—C14—H14B	110.2
C5—C6—C1	119.82 (18)	H14A—C14—H14B	108.5
N1—C7—C8	121.55 (17)	C14—C15—C15ⁱ	113.7 (2)
N1—C7—S1	114.57 (13)	C14—C15—H15A	108.8
C8—C7—S1	123.83 (13)	C15ⁱ—C15—H15A	108.8
C9—C8—C13	117.81 (17)	C14—C15—H15B	108.8
C9—C8—C7	117.97 (16)	C15ⁱ—C15—H15B	108.8
C13—C8—C7	124.20 (17)	H15A—C15—H15B	107.7
C10—C9—C8	121.54 (18)	C7—N1—C6	111.40 (16)
C10—C9—H9	119.2	C13—O1—C14	117.86 (14)
C8—C9—H9	119.2	C1—S1—C7	89.39 (9)

C6—C1—C2—C3	0.9 (3)	C10—C11—C12—C13	0.4 (3)
S1—C1—C2—C3	−179.08 (15)	C11—C12—C13—O1	−179.97 (18)
C1—C2—C3—C4	0.5 (3)	C11—C12—C13—C8	0.6 (3)
C2—C3—C4—C5	−1.4 (3)	C9—C8—C13—O1	179.64 (16)
C3—C4—C5—C6	0.8 (3)	C7—C8—C13—O1	0.9 (3)
C4—C5—C6—N1	−178.41 (18)	C9—C8—C13—C12	−0.9 (3)
C4—C5—C6—C1	0.7 (3)	C7—C8—C13—C12	−179.58 (17)
C2—C1—C6—N1	177.62 (16)	O1—C14—C15—C15ⁱ	−69.4 (3)
S1—C1—C6—N1	−2.4 (2)	C8—C7—N1—C6	−177.23 (15)
C2—C1—C6—C5	−1.6 (3)	S1—C7—N1—C6	0.4 (2)
S1—C1—C6—C5	178.43 (14)	C5—C6—N1—C7	−179.52 (17)
N1—C7—C8—C9	8.4 (3)	C1—C6—N1—C7	1.3 (2)
S1—C7—C8—C9	−168.92 (14)	C12—C13—O1—C14	3.6 (3)
N1—C7—C8—C13	−172.87 (18)	C8—C13—O1—C14	−176.95 (16)
S1—C7—C8—C13	9.8 (2)	C15—C14—O1—C13	179.99 (15)
C13—C8—C9—C10	0.2 (3)	C6—C1—S1—C7	2.04 (14)
C7—C8—C9—C10	179.00 (18)	C2—C1—S1—C7	−177.94 (18)
C8—C9—C10—C11	0.8 (3)	N1—C7—S1—C1	−1.44 (14)
C9—C10—C11—C12	−1.1 (3)	C8—C7—S1—C1	176.08 (15)

Symmetry code: (i) −x, −y+1, −z+1.

Experimental details

Crystal data
Chemical formula	C₃₀H₂₄N₂O₂S₂
M_r	508.63
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	14.3251 (13), 4.8992 (3), 17.4954 (17)
β (°)	102.522 (7)
V (Å³)	1198.65 (18)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.26
Crystal size (mm)	0.80 × 0.36 × 0.08

Data collection
Diffractometer	Stoe IPDSII diffractometer
Absorption correction	Integration (X-RED32; Stoe & Cie, 2002)
T_min, T_max	0.442, 0.936
No. of measured, independent and observed [I > 2σ(I)] reflections	14397, 2339, 1456
R_int	0.075
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.034, 0.069, 0.84
No. of reflections	2339
No. of parameters	163
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.14, −0.19

Computer programs: X-AREA (Stoe & Cie, 2002), X-RED32 (Stoe & Cie, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

The observed 'π···π' interaction distances (Å) for the title compound. top

Cg-Cgⁱ	d_centroids	d_{perpendicular}
Cg1-Cg2_i	3.775 (11)	3.515
Cg1-Cg3_i	3.7934 (12)	3.59

Cg1, Cg2 and Cg3 are the centroids of atoms S1/N1/C1/C6/C7, (C1–C6) and (C8–C13) rings, respectively. Symmetry code: (i) x, 1+y, z

Acknowledgements

The authors acknowledge the Faculty of Arts and Sciences, Ondokuz Mayıs University, Turkey, for use of the Stoe IPDSII diffractometer (purchased under grant No. F.279 of the University Research Fund).

References

Chopade, R. S., Bahekar, R. H., Khedekar, P. B., Bhusari, K. P. & Rao, A. R. R. (2002). Arch. Pharm. 335, 381–388. Web of Science CrossRef CAS Google Scholar
Delmas, F., Di Giorgio, C., Robin, M., Azas, N., Gasquet, M., Detang, C., Costa, M., Timon-David, P. & Galy, J. P. (2002). Antimicrob. Agents Chemother. 46, 2588–2594. Web of Science CrossRef PubMed CAS Google Scholar
Di Nunno, L., Franchini, C., Scilimati, A., Sinicropi, M. S. & Tortorella, P. (2000). Tetrahedron Asymmetry, 11, 1571–1583. Web of Science CrossRef CAS Google Scholar
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838. CrossRef CAS IUCr Journals Google Scholar
Gökhan, N., Aktay, G. & Erdoğan, H. (2004). Turk. J. Chem. 28, 123–132. Google Scholar
Karalı, N., Cesur, N., Gürsoy, A., Ateş, O., Özden, S., Otuk, G. & Birteksöz, S. (2004). Indian J. Chem. B43, 212–216. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Sieroń, L. & Bukowska-Strżyzewska, M. (1999). Acta Cryst. C55, 167–169. Web of Science CSD CrossRef IUCr Journals Google Scholar
Stoe & Cie (2002). X-AREA (Version 1.18) and X-RED32 (Version 1.04). Stoe & Cie, Darmstadt, Germany. Google Scholar
Temel, H., Alp, H., İlhan, S. & Ziyadanoğulları, B. (2008). J. Coord. Chem. In the press. Google Scholar
Usman, A., Fun, H.-K., Chantrapromma, S., Zhang, M., Chen, Z.-F., Tang, Y.-Z., Shi, S.-M. & Liang, H. (2003). Acta Cryst. E59, m41–m43. Web of Science CSD CrossRef IUCr Journals Google Scholar
Weinstock, J., Gaitanopoulos, D. E., Stringer, O. D., Franz, R. G., Hieble, J. P., Kinter, L. B., Mann, W. A., Flaim, K. E. & Gessner, G. (1987). J. Med. Chem. 30, 1166–1176. CrossRef CAS PubMed Web of Science Google Scholar