4-Ethyl-3-(2-thienylmeth­yl)-Δ2-1,2,4-triazoline-5-thione

Wujec, M.; Mazur, L.; Rzączyńska, Z.

doi:10.1107/S1600536809000440

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 65| Part 2| February 2009| Page o274

doi:10.1107/S1600536809000440

Open

access

4-Ethyl-3-(2-thienylmethyl)-Δ²-1,2,4-triazoline-5-thione

Monika Wujec,^a Liliana Mazur ^b ^* and Zofia Rzączyńska ^b

^aDepartment of Organic Chemistry, Faculty of Pharmacy, Medical University, 20081 Lublin, Poland, and ^bDepartment of General and Coordination Chemistry, Faculty of Chemistry, Maria Curie-Skłodowska University, 20031 Lublin, Poland
^*Correspondence e-mail: lmazur2@op.pl

(Received 16 December 2008; accepted 6 January 2009; online 10 January 2009)

The title compound, C₉H₁₁N₃S₂, exists in the thione form in the crystal structure. The central triazole ring is almost perpendicular to the thiophene ring which is disordered over two orientations [dihedral angles of 88.5 (7) and 85.7 (8)° for the two orientations]. The crystal structure is stabilized by strong intermolecular N—H⋯S hydrogen bonds, forming centrosymmetric dimers, and by some weak C—H⋯S interactions.

Related literature

For background on the applications of 1,2,4-triazole and its derivatives, see: Ünver et al. (2006 ); Dobosz et al. (2002 ); Jian et al. (2005 ); Maliszewska-Guz et al. (2005 ); Al-Soud et al. (2004 ); Amir & Shikha (2004 ); Collin et al. (2003 ); Demirayak et al. (2000 ); Palaska et al. (2002 ); Shivarama et al. (2006 ). For details of the synthesis, see: Wujec et al. (2004 , 2007 ). For related structures, see: Yilmaz et al. (2005 ).

Experimental

Crystal data

C₉H₁₁N₃S₂
M_r = 225.33
Monoclinic, P 2₁ /c
a = 6.813 (1) Å
b = 17.119 (2) Å
c = 9.846 (1) Å
β = 100.88 (1)°
V = 1127.7 (2) Å³
Z = 4
Mo Kα radiation
μ = 0.44 mm⁻¹
T = 295 (2) K
0.47 × 0.30 × 0.16 mm

Data collection

Oxford Diffraction Xcalibur diffractometer
Absorption correction: none
2735 measured reflections
2592 independent reflections
1130 reflections with I > 2σ(I)
R_int = 0.026

Refinement

R[F² > 2σ(F²)] = 0.052
wR(F²) = 0.111
S = 0.98
2592 reflections
147 parameters
H-atom parameters constrained
Δρ_max = 0.16 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯S1ⁱ	0.86	2.44	3.287 (3)	169
C6—H6a⋯S1ⁱⁱ	0.97	2.99	3.949 (4)	172
C9—H9⋯S1ⁱⁱⁱ	0.93	2.97	3.659 (4)	132
C8′—H8′⋯S2^iv	0.93	3.02	3.928 (7)	166
Symmetry codes: (i) -x, -y+1, -z+1; (ii) x+1, y, z; (iii) $[x+1, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ ; (iv) -x+1, -y+1, -z+2.

Data collection: CrysAlis CCD (Oxford Diffraction, 2005 $[Oxford Diffraction (2005). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ); cell refinement: CrysAlis RED (Oxford Diffraction, 2005 $[Oxford Diffraction (2005). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL/PC (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 and enCIFer (Allen et al., 2004 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809000440/at2696sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809000440/at2696Isup2.hkl

checkCIF report

Comment top

1,2,4-Triazole and its derivatives represent one of the most biologically active classes of compounds possessing a wide spectrum of activities, such as antimicrobial, fungicidal, anti-inflammatory, antiviral, antitumor or analgesic activity (Al-Soud et al., 2004; Amir & Shikha, 2004; Collin et al., 2003; Demirayak et al., 2000; Maliszewska-Guz et al., 2005; Palaska et al., 2002; Shivarama et al., 2006; Wujec et al. 2007). The 1,2,4-triazole nucleus has been incorporated into a wide variety of therapeutically important drugs e.g. Fluconazole, Itraconazole, Anastrazole, Ribavirin. In recent years 1,2,4-triazole finds an important place in medicinal chemistry as material for the preparation of antibacterial agents (Demirayak et al., 2000). In this context, we described the synthesis and antibacterial activity of a series of 1,2,4-triazoline-5-thione derivatives (Wujec et al. 2004). In the present paper we report the structure of one of them: 4-ethyl-3-(thiophene-2-yl-methyl)-Δ²-1,2,4-triazoline-5-thione (I). This compound inhibite the growth of Trichophyton spp.

In the title compound (Fig. 1), the C5—S1 bond length [1.673 (2) Å] is within the values observed for a C=S double bond. In the planar 1,2,4-triazole ring the C3=N2 bond is clearly double, being much shorter then the other C—N bonds. This distance is also comparable to literature data (Yilmaz et al., 2005). The thiophene ring is disordered over two orientatians with respect to the C6—C7 bond; the dihedral angles between the triazole and the thiophene rings for the two orientations of the second one are 88.5 (7) and 85.7 (8)°. Atoms C6 and C11 lie in the plane of triazole, whereas the ethyl atom C12 is signifficantly displaced from the plane of central system as indicate from the torsion angle C5—N4—C11—C12, being of 83.3 (3)°.

The crystal structure is stabilized by strong intermolecular N1—H1···S1 hydrogen bonds, forming centrosymmetric dimers (Fig. 2), together with some weak C—H···S interactions (Table 1).

Related literature top

For background on the applications of 1,2,4-triazole and its derivatives, see: Ünver et al. (2006); Dobosz et al. (2002); Jian et al. (2005); Maliszewska-Guz et al. (2005); Al-Soud et al. (2004); Amir & Shikha (2004); Collin et al. (2003); Demirayak et al. (2000); Palaska et al. (2002); Shivarama et al. (2006). For details of the synthesis, see: Wujec et al. (2004, 2007). For a related structure, see: Yilmaz et al. (2005).

Experimental top

4-Ethyl-3-(thiophene-2-yl-methyl)-Δ²-1,2,4-triazoline-5-thione was synthesized according to the method which was described in a previous paper (Wujec et al., 2004). Prism-shaped colourless single crystals, suitable for X-ray diffraction measurements, were obtained by the slow evaporation of a 2-propanol solution of the compound.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2005); cell refinement: CrysAlis RED (Oxford Diffraction, 2005); data reduction: CrysAlis RED (Oxford Diffraction, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL/PC (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and enCIFer (Allen et al., 2004).

Figures top

	Fig. 1. The molecular structure of (I), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. Both disordered components are shown.
	Fig. 2. The molecular packing of (I), viewed down the a axis. Dashed lines indicate hydrogen bonds.

4-Ethyl-3-(2-thienylmethyl)-Δ²-1,2,4-triazoline-5-thione top

Crystal data top

C₉H₁₁N₃S₂	F(000) = 472
M_r = 225.33	D_x = 1.327 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 69 reflections
a = 6.813 (1) Å	θ = 6–14°
b = 17.119 (2) Å	µ = 0.44 mm⁻¹
c = 9.846 (1) Å	T = 295 K
β = 100.88 (1)°	Prism, colourless
V = 1127.7 (2) Å³	0.47 × 0.30 × 0.16 mm
Z = 4

Data collection top

Oxford Diffraction Xcalibur diffractometer	R_int = 0.026
Radiation source: fine-focus sealed tube	θ_max = 27.6°, θ_min = 3.9°
Graphite monochromator	h = −8→8
ω–2θ scans	k = 0→22
2735 measured reflections	l = 0→12
2592 independent reflections	3 standard reflections every 100 reflections
1130 reflections with I > 2σ(I)	intensity decay: 0.1%

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)] = 0.052	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.111	H-atom parameters constrained
S = 0.98	w = 1/[σ²(F_o²) + (0.0395P)² + 0.2245P] where P = (F_o² + 2F_c²)/3
2592 reflections	(Δ/σ)_max = 0.002
147 parameters	Δρ_max = 0.16 e Å⁻³
0 restraints	Δρ_min = −0.17 e Å⁻³

Crystal data top

C₉H₁₁N₃S₂	V = 1127.7 (2) Å³
M_r = 225.33	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 6.813 (1) Å	µ = 0.44 mm⁻¹
b = 17.119 (2) Å	T = 295 K
c = 9.846 (1) Å	0.47 × 0.30 × 0.16 mm
β = 100.88 (1)°

Data collection top

Oxford Diffraction Xcalibur diffractometer	R_int = 0.026
2735 measured reflections	3 standard reflections every 100 reflections
2592 independent reflections	intensity decay: 0.1%
1130 reflections with I > 2σ(I)

Refinement top

R[F² > 2σ(F²)] = 0.052	0 restraints
wR(F²) = 0.111	H-atom parameters constrained
S = 0.98	Δρ_max = 0.16 e Å⁻³
2592 reflections	Δρ_min = −0.17 e Å⁻³
147 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	Occ. (<1)
N1	0.2725 (3)	0.49647 (12)	0.6098 (2)	0.0563 (6)
H1	0.1684	0.4675	0.5868	0.068*
N2	0.4538 (3)	0.46832 (13)	0.6760 (2)	0.0598 (6)
C3	0.5669 (4)	0.52970 (16)	0.6930 (3)	0.0547 (7)
N4	0.4644 (3)	0.59498 (12)	0.6394 (2)	0.0504 (5)
C5	0.2730 (3)	0.57271 (16)	0.5846 (2)	0.0501 (6)
S1	0.08621 (10)	0.62899 (4)	0.50362 (7)	0.0654 (3)
C6	0.7818 (4)	0.52769 (17)	0.7589 (3)	0.0703 (8)
H6A	0.8601	0.5469	0.6933	0.084*
H6B	0.8205	0.4739	0.7799	0.084*
S2	0.7156 (9)	0.5621 (3)	1.0253 (6)	0.0683 (11)	0.538 (6)
C8	0.982 (3)	0.6272 (12)	0.921 (2)	0.123 (10)	0.538 (6)
H8	1.0760	0.6381	0.8662	0.148*	0.538 (6)
C8'	0.757 (3)	0.5727 (13)	1.003 (2)	0.079 (9)	0.462 (6)
H8'	0.6549	0.5383	1.0138	0.094*	0.462 (6)
S2'	1.0016 (7)	0.6482 (5)	0.9087 (7)	0.0949 (14)	0.462 (6)
C7	0.8316 (5)	0.57473 (19)	0.8885 (3)	0.0588 (8)
C9	0.9766 (6)	0.6655 (2)	1.0589 (5)	0.1017 (13)
H9	1.0536	0.7077	1.0974	0.122*
C10	0.8435 (6)	0.6283 (2)	1.1134 (3)	0.0885 (10)
H10	0.8241	0.6403	1.2020	0.106*
C11	0.5372 (4)	0.67518 (16)	0.6362 (3)	0.0670 (8)
H11A	0.4782	0.6990	0.5485	0.080*
H11B	0.6810	0.6744	0.6425	0.080*
C12	0.4875 (5)	0.72417 (17)	0.7527 (3)	0.0815 (9)
H12A	0.5369	0.7763	0.7462	0.098*
H12B	0.5488	0.7017	0.8397	0.098*
H12C	0.3452	0.7257	0.7463	0.098*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0502 (12)	0.0529 (14)	0.0614 (14)	−0.0035 (10)	−0.0008 (10)	−0.0031 (11)
N2	0.0522 (13)	0.0619 (14)	0.0620 (15)	0.0057 (11)	0.0022 (11)	−0.0059 (12)
C3	0.0486 (15)	0.0655 (17)	0.0495 (16)	0.0044 (14)	0.0081 (12)	−0.0053 (15)
N4	0.0448 (12)	0.0561 (13)	0.0489 (12)	−0.0051 (11)	0.0056 (9)	−0.0040 (10)
C5	0.0512 (15)	0.0537 (16)	0.0441 (14)	−0.0029 (12)	0.0056 (12)	−0.0055 (13)
S1	0.0578 (4)	0.0571 (4)	0.0739 (5)	−0.0009 (3)	−0.0067 (3)	0.0003 (4)
C6	0.0456 (16)	0.088 (2)	0.075 (2)	0.0055 (15)	0.0052 (14)	−0.0120 (17)
S2	0.070 (2)	0.0744 (16)	0.0589 (15)	−0.0131 (15)	0.0081 (15)	−0.0015 (13)
C8	0.159 (19)	0.120 (15)	0.102 (10)	0.015 (11)	0.056 (10)	0.031 (9)
C8'	0.057 (9)	0.096 (10)	0.084 (15)	−0.022 (6)	0.015 (6)	0.018 (7)
S2'	0.0717 (17)	0.110 (3)	0.097 (3)	−0.0346 (17)	−0.0010 (15)	0.010 (2)
C7	0.0398 (15)	0.0610 (19)	0.071 (2)	−0.0056 (14)	−0.0015 (15)	0.0057 (17)
C9	0.104 (3)	0.072 (2)	0.109 (3)	−0.029 (2)	−0.033 (2)	0.008 (2)
C10	0.116 (3)	0.081 (2)	0.061 (2)	0.006 (2)	−0.002 (2)	−0.002 (2)
C11	0.0566 (17)	0.0687 (19)	0.0731 (19)	−0.0165 (14)	0.0055 (14)	0.0078 (17)
C12	0.079 (2)	0.0605 (18)	0.098 (2)	−0.0082 (15)	−0.0005 (17)	−0.0105 (18)

Geometric parameters (Å, º) top

N1—C5	1.329 (3)	C8—H8	0.9300
N1—N2	1.370 (3)	C8'—C7	1.32 (2)
N1—H1	0.8600	C8'—C10	1.48 (2)
N2—C3	1.295 (3)	C8'—H8'	0.9300
C3—N4	1.370 (3)	S2'—C9	1.549 (10)
C3—C6	1.485 (3)	S2'—C7	1.695 (6)
N4—C5	1.368 (3)	C9—C10	1.304 (5)
N4—C11	1.462 (3)	C9—H9	0.9300
C5—S1	1.673 (2)	C10—H10	0.9300
C6—C7	1.493 (4)	C11—C12	1.510 (4)
C6—H6A	0.9700	C11—H11A	0.9700
C6—H6B	0.9700	C11—H11B	0.9700
S2—C10	1.584 (7)	C12—H12A	0.9600
S2—C7	1.699 (6)	C12—H12B	0.9600
C8—C7	1.355 (17)	C12—H12C	0.9600
C8—C9	1.51 (2)

C5—N1—N2	113.6 (2)	C8—C7—C6	126.8 (11)
C5—N1—H1	123.2	C8'—C7—S2'	106.5 (10)
N2—N1—H1	123.2	C6—C7—S2'	122.7 (4)
C3—N2—N1	103.7 (2)	C8—C7—S2	110.0 (11)
N2—C3—N4	111.4 (2)	C6—C7—S2	123.0 (3)
N2—C3—C6	123.4 (2)	S2'—C7—S2	114.3 (4)
N4—C3—C6	125.2 (3)	C10—C9—C8	107.1 (7)
C5—N4—C3	107.7 (2)	C10—C9—S2'	120.6 (4)
C5—N4—C11	123.7 (2)	C10—C9—H9	126.5
C3—N4—C11	128.6 (2)	C8—C9—H9	126.5
N1—C5—N4	103.6 (2)	S2'—C9—H9	112.5
N1—C5—S1	128.8 (2)	C9—C10—C8'	103.1 (8)
N4—C5—S1	127.6 (2)	C9—C10—S2	118.6 (4)
C3—C6—C7	114.1 (2)	C9—C10—H10	120.7
C3—C6—H6A	108.7	C8'—C10—H10	136.2
C7—C6—H6A	108.7	S2—C10—H10	120.7
C3—C6—H6B	108.7	N4—C11—C12	112.3 (2)
C7—C6—H6B	108.7	N4—C11—H11A	109.1
H6A—C6—H6B	107.6	C12—C11—H11A	109.1
C10—S2—C7	93.0 (4)	N4—C11—H11B	109.1
C7—C8—C9	110.7 (14)	C12—C11—H11B	109.1
C7—C8—H8	124.7	H11A—C11—H11B	107.9
C9—C8—H8	124.7	C11—C12—H12A	109.5
C7—C8'—C10	116.3 (13)	C11—C12—H12B	109.5
C7—C8'—H8'	121.9	H12A—C12—H12B	109.5
C10—C8'—H8'	121.9	C11—C12—H12C	109.5
C9—S2'—C7	93.4 (4)	H12A—C12—H12C	109.5
C8'—C7—C8	102.3 (15)	H12B—C12—H12C	109.5
C8'—C7—C6	130.7 (10)

C5—N1—N2—C3	0.8 (3)	C3—C6—C7—S2'	−122.1 (4)
N1—N2—C3—N4	−0.4 (3)	C3—C6—C7—S2	54.9 (4)
N1—N2—C3—C6	−178.8 (2)	C9—S2'—C7—C8'	3.9 (11)
N2—C3—N4—C5	−0.1 (3)	C9—S2'—C7—C8	−58 (9)
C6—C3—N4—C5	178.2 (2)	C9—S2'—C7—C6	−178.6 (3)
N2—C3—N4—C11	−179.4 (2)	C9—S2'—C7—S2	4.1 (5)
C6—C3—N4—C11	−1.0 (4)	C10—S2—C7—C8'	−2 (9)
N2—N1—C5—N4	−0.9 (3)	C10—S2—C7—C8	5.2 (10)
N2—N1—C5—S1	178.5 (2)	C10—S2—C7—C6	179.8 (2)
C3—N4—C5—N1	0.6 (3)	C10—S2—C7—S2'	−2.9 (4)
C11—N4—C5—N1	179.9 (2)	C7—C8—C9—C10	8.5 (15)
C3—N4—C5—S1	−178.8 (2)	C7—C8—C9—S2'	−145 (4)
C11—N4—C5—S1	0.5 (3)	C7—S2'—C9—C10	−4.2 (5)
N2—C3—C6—C7	−117.9 (3)	C7—S2'—C9—C8	25 (3)
N4—C3—C6—C7	63.9 (4)	C8—C9—C10—C8'	−5.0 (13)
C10—C8'—C7—C8	5 (2)	S2'—C9—C10—C8'	2.8 (11)
C10—C8'—C7—C6	179.6 (7)	C8—C9—C10—S2	−4.9 (9)
C10—C8'—C7—S2'	−3.2 (19)	S2'—C9—C10—S2	2.9 (6)
C10—C8'—C7—S2	178 (11)	C7—C8'—C10—C9	0.6 (19)
C9—C8—C7—C8'	−7.5 (18)	C7—C8'—C10—S2	−179 (6)
C9—C8—C7—C6	177.2 (6)	C7—S2—C10—C9	0.2 (4)
C9—C8—C7—S2'	113 (9)	C7—S2—C10—C8'	1 (4)
C9—C8—C7—S2	−8.4 (15)	C5—N4—C11—C12	83.3 (3)
C3—C6—C7—C8'	54.7 (14)	C3—N4—C11—C12	−97.5 (3)
C3—C6—C7—C8	−131.4 (11)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···S1ⁱ	0.86	2.44	3.287 (3)	169
C6—H6a···S1ⁱⁱ	0.97	2.99	3.949 (4)	172
C9—H9···S1ⁱⁱⁱ	0.93	2.97	3.659 (4)	132
C8′—H8′···S2^iv	0.93	3.02	3.928 (7)	166

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

Experimental details

Crystal data
Chemical formula	C₉H₁₁N₃S₂
M_r	225.33
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	295
a, b, c (Å)	6.813 (1), 17.119 (2), 9.846 (1)
β (°)	100.88 (1)
V (Å³)	1127.7 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.44
Crystal size (mm)	0.47 × 0.30 × 0.16

Data collection
Diffractometer	Oxford Diffraction Xcalibur diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	2735, 2592, 1130
R_int	0.026
(sin θ/λ)_max (Å⁻¹)	0.651

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.052, 0.111, 0.98
No. of reflections	2592
No. of parameters	147
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.16, −0.17

Computer programs: CrysAlis CCD (Oxford Diffraction, 2005), CrysAlis RED (Oxford Diffraction, 2005), SHELXS97 (Sheldrick, 2008), SHELXTL/PC (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008) and enCIFer (Allen et al., 2004).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···S1ⁱ	0.86	2.44	3.287 (3)	169
C6—H6a···S1ⁱⁱ	0.97	2.99	3.949 (4)	172
C9—H9···S1ⁱⁱⁱ	0.93	2.97	3.659 (4)	132
C8'—H8'···S2^iv	0.93	3.02	3.928 (7)	166

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

References

Allen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst. 37, 335–338. Web of Science CrossRef CAS IUCr Journals Google Scholar
Al-Soud, Y. A., Al-Dweri, M. N. & Al-Masoudi, N. A. (2004). Farmaco, 59, 775–783. CrossRef PubMed CAS Google Scholar
Amir, M. & Shikha, K. (2004). Eur. J. Med. Chem. 39, 535–545. Web of Science CrossRef PubMed CAS Google Scholar
Collin, X., Sauleau, A. & Coulon, J. (2003). Bioorg. Med. Chem. Lett. 13, 2601–2605. Web of Science CrossRef PubMed CAS Google Scholar
Demirayak, S., Benkli, K. & Güven, K. (2000). Eur. J. Med. Chem. 35, 1037–1040. Web of Science CrossRef PubMed CAS Google Scholar
Dobosz, M., Sruga, M., Chodkowska, A., Jagiello-Wojtowicz, E., Stepniak, K. & Koziol, A. E. (2002). Acta Pol. Pharm. 59, 281–290. PubMed CAS Google Scholar
Jian, F.-F., Bai, Z.-S., Li, K. & Xiao, H.-L. (2005). Acta Cryst. E61, o393–o395. Web of Science CSD CrossRef IUCr Journals Google Scholar
Maliszewska-Guz, A., Wujec, M., Pitucha, M., Dobosz, M., Chodkowska, A., Jagiello-Wojtowicz, E., Mazur, L. & Koziol, A. E. (2005). Collect. Czech. Chem. Commun. 70, 51–62. Web of Science CSD CrossRef CAS Google Scholar
Oxford Diffraction (2005). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England. Google Scholar
Palaska, E., Sahin, G., Kelicen, P., Durlu, T. N. & Altinok, G. (2002). Farmaco, 57, 101–107. 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
Shivarama, H. B., Sooryanarayana, R. B., Sarojini, B. K., Akberali, P. M. & Suchetha, K. N. (2006). Eur. J. Med. Chem. 41, 657–663. PubMed Google Scholar
Ünver, Y., Ustabaş, R., Çoruh, U., Sancak, K. & Vázquez-López, E. M. (2006). Acta Cryst. E62, o3938–o3939. Web of Science CSD CrossRef IUCr Journals Google Scholar
Wujec, M., Kosikowska, U., Paneth, P. & Malm, A. (2007). Heterocycles, 71, 2617–2626. CrossRef CAS Google Scholar
Wujec, M., Pitucha, M., Dobosz, M., Kosikowska, U. & Malm, A. (2004). Acta Pharm. 54, 251–260. PubMed CAS Google Scholar
Yilmaz, V. T., Kazak, C., Ağar, E., Kahveci, B. & Guven, K. (2005). Acta Cryst. C61, o101–o104. CSD CrossRef CAS IUCr Journals Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 65| Part 2| February 2009| Page o274

doi:10.1107/S1600536809000440

Open

access