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Acta Crystallogr Sect E Struct Rep Online. 2009 June 1; 65(Pt 6): o1350–o1351.
Published online 2009 May 20. doi:  10.1107/S1600536809018376
PMCID: PMC2969805

4-Benzyl-6-p-tolyl­pyridazin-3(2H)-one

Abstract

The title compound, C18H16N2O, is a new dihydro­pyridazin-3(2H)-one derivative synthesized in one step by condensation of α-benzyl­idene-γ-tolyl­butenolide with hydrazine. The mol­ecule is not planar; the tolyl and pyridazine rings are twisted with respect to each other making a dihedral angle of 27.35 (9)° and the benzyl ring is nearly perpendicular to the pyridazine ring with a dihedral angle of 85.24 (5)°. In the crystal structure, inversion dimers arise, being linked by pairs of N—H(...)O hydrogen bonds. Weak C—H(...)O hydrogen bonds and weak offset π–π stacking stabilize the packing. The π–π stacking occurs between the pyridazine rings of symmetry-related mol­ecules, with a centroid–centroid distance of 3.748 Å, an inter­planar distance of 3.605 Å and a slippage of 1.024 Å.

Related literature

For related compounds displaying biological activities, see: Sayed et al. (2002 [triangle]); Frolov et al. (2004 [triangle]); Piaz et al. (1994 [triangle]); Coelho et al. (2004 [triangle]); Malinka et al. (2004 [triangle]); Ogretir et al. (2002 [triangle]); Okcelik et al. (2003 [triangle]); Sotelo et al. (2003 [triangle]); Youssef et al. (2005 [triangle]). For related structures, see: Cao et al. (2003 [triangle]); Daran et al. (2006 [triangle]); Fihi et al. (1995 [triangle]); Filler & Piasek (1973 [triangle]); Roussel et al. (2000 [triangle], 2003 [triangle]). For graph-set theory, see: Bernstein et al. (1995 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-o1350-scheme1.jpg

Experimental

Crystal data

  • C18H16N2O
  • M r = 276.33
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1350-efi1.jpg
  • a = 7.2487 (4) Å
  • b = 10.4469 (5) Å
  • c = 19.1869 (9) Å
  • β = 99.598 (5)°
  • V = 1432.62 (12) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.08 mm−1
  • T = 180 K
  • 0.50 × 0.48 × 0.08 mm

Data collection

  • Oxford Diffraction Xcalibur diffractometer
  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006 [triangle]) T min = 0.965, T max = 0.993
  • 10925 measured reflections
  • 2914 independent reflections
  • 1622 reflections with I > 2σ(I)
  • R int = 0.044

Refinement

  • R[F 2 > 2σ(F 2)] = 0.041
  • wR(F 2) = 0.121
  • S = 0.94
  • 2914 reflections
  • 190 parameters
  • H-atom parameters constrained
  • Δρmax = 0.20 e Å−3
  • Δρmin = −0.20 e Å−3

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 [triangle]); cell refinement: CrysAlis RED (Oxford Diffraction, 2006 [triangle]); data reduction: CrysAlis RED; program(s) used to solve structure: SIR97 (Altomare et al., 1999 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 [triangle]), ORTEP-3 for Windows (Farrugia, 1997 [triangle]) and PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809018376/bg2256sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809018376/bg2256Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Comment

In recent years a number of 6-arylpyridazin-3(2H)-ones have been reported to possess antimicrobial (Sayed et al., 2002), anti-inflammatory (Frolov et al., 2004), herbicidal (Piaz et al.,1994), antiplatelet activities (Coelho et al., 2004), anticancer effects (Malinka et al., 2004), antifeedant (Cao et al., 2003), antihypertensive (Ogretir et al.,2002), potent analgesic (Okcelik et al., 2003) and other anticipated biological(Youssef et al., 2005) and pharmacological properties (Sotelo et al., 2003).

In previous papers treating the reactivity of lactones bearing an exocyclic carbon-carbon double bond with 1,3-dipoles (Fihi et al., 1995; Roussel et al., 2000, 2003; Daran et al., 2006), we reported that cycloaddition reactions lead to spiroheterocyclic compounds or evolutive products. In this paper, we describe the synthesis of a new dihydro-2 H– pyridazin-3-onederivative. The condensation ofα-benzylidene-γ-tolylbutenolide(1) and hydrazine (2) in reflux in toluene leads in one step to pyridazin-3-one(3). (Scheme).

Since the 1H and 13CNMR studies did not provide unambiguous information, a single-crystal of (3) was subjected to X-ray diffraction analysis to determine the structure of the product.

The molecule is not planar, the tolyl and the pyridazin rings are twisted to each other making a dihedral angle of 27.35 (9)° and the phenyl ring is nearly perpendicular to the pyridazin ring with a dihedral angle of 85.24 (5)° (Fig. 1).

The molecules are connected two by two through N—H···O hydrogen bonds with a R22(8) graph set motif (Bernstein et al., 1995) then building a pseudo dimer arranged around the inversion center (Fig. 1, Table 1). Weak C—H···O hydrogen bonds and weak offset π-π stacking stabilize the packing. The π-π stacking occurs between the pyridazin rings of symmetry related molecules with centroid-to-centroid distance of 3.748 Å and interplanar distance of 3.605Å and a slippage of 1.024 Å.

Experimental

α-benzylidene-γ-tolylbutenolide (1) was synthesized according to the literature procedure (Filler & Piasek, 1973). (0.036 g, 1.125 mmol) of hydrazine was added to a solution of (1) (0.2 g, 0.76 mmol) in toluene (25 ml) and the mixture was stirred at reflux for 24 h. The solvent was then evaporated under reduced pressure. The residue was recrystallized from ethanol, and purified by chromatography on silica gel (eluant: ethyl acetate / hexane: 20 / 80). The pyridazinone was recrystallized from ethanol.

Refinement

All H atoms attached to C atoms and N atom were fixed geometrically and treated as riding with C—H = 0.99 Å (methylene), 0.98Å (methyl) or 0.95 Å (aromatic) and N—H =0.88 Å with Uiso(H) = 1.2Ueq(C or N)or Uiso(H) = 1.5Ueq(Cmethyl).

Figures

Fig. 1.
Molecular view of (I) with the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are represented as small spheres of arbitrary radii and hydrogen bonds are shown as dashed lines.[symmetry codes: (i) -x + 1, ...
Fig. 2.
The formation of the title compound.

Crystal data

C18H16N2OF(000) = 584
Mr = 276.33Dx = 1.281 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 3436 reflections
a = 7.2487 (4) Åθ = 2.8–32.0°
b = 10.4469 (5) ŵ = 0.08 mm1
c = 19.1869 (9) ÅT = 180 K
β = 99.598 (5)°Fragment, colourless
V = 1432.62 (12) Å30.50 × 0.48 × 0.08 mm
Z = 4

Data collection

Oxford Diffraction Xcalibur diffractometer2914 independent reflections
Radiation source: fine-focus sealed tube1622 reflections with I > 2σ(I)
graphiteRint = 0.044
Detector resolution: 8.2632 pixels mm-1θmax = 26.4°, θmin = 2.9°
ω and [var phi] scansh = −7→9
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)k = −12→13
Tmin = 0.965, Tmax = 0.993l = −23→23
10925 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.121H-atom parameters constrained
S = 0.94w = 1/[σ2(Fo2) + (0.0651P)2 + 0.0125P] where P = (Fo2 + 2Fc2)/3
2914 reflections(Δ/σ)max = 0.008
190 parametersΔρmax = 0.20 e Å3
0 restraintsΔρmin = −0.19 e Å3

Special details

Experimental. All H atoms attached to C atoms and N atom were fixed geometrically and treated as riding with C—H = 0.93 Å (aromatic), 0.97 Å (methylene), 0.98Å (methyl) and N—H = 0.86 Å with Uiso(H) = xUeq(C or N) where x=1.2 or 1.5(methyl).Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm, CrysAlis RED (Oxford Diffraction, 2006)
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)

xyzUiso*/UeqOcc. (<1)
O10.58992 (17)−0.03563 (12)0.42289 (6)0.0387 (4)
N10.8190 (2)0.19591 (14)0.54067 (8)0.0336 (4)
N20.7005 (2)0.10629 (14)0.50803 (7)0.0335 (4)
H20.60670.08480.52940.040*
C10.9570 (3)0.22886 (16)0.50837 (9)0.0296 (4)
C20.7092 (3)0.04582 (17)0.44647 (9)0.0297 (4)
C30.8621 (2)0.08373 (17)0.41181 (9)0.0296 (4)
C40.9807 (2)0.17325 (17)0.44281 (9)0.0309 (4)
H41.08210.19990.42060.037*
C111.0846 (3)0.32907 (17)0.54285 (9)0.0314 (5)
C121.0234 (3)0.41994 (17)0.58693 (9)0.0360 (5)
H120.89830.41680.59560.043*
C131.1423 (3)0.51460 (18)0.61821 (10)0.0398 (5)
H131.09740.57570.64800.048*
C141.3252 (3)0.52198 (18)0.60691 (10)0.0392 (5)
C151.3863 (3)0.43020 (19)0.56396 (10)0.0414 (5)
H151.51220.43260.55610.050*
C161.2684 (3)0.33473 (18)0.53210 (9)0.0372 (5)
H161.31410.27310.50280.045*
C171.4555 (3)0.6246 (2)0.64031 (11)0.0547 (6)
H17A1.57800.61380.62590.082*0.50
H17B1.46910.61820.69190.082*0.50
H17C1.40440.70870.62500.082*0.50
H17D1.38970.68000.66930.082*0.50
H17E1.49860.67560.60330.082*0.50
H17F1.56330.58510.67020.082*0.50
C310.8735 (3)0.02039 (18)0.34214 (9)0.0359 (5)
H31A0.9169−0.06880.35130.043*
H31B0.74630.01700.31380.043*
C321.0013 (3)0.08604 (17)0.29952 (9)0.0292 (4)
C330.9342 (3)0.18115 (18)0.25246 (9)0.0376 (5)
H330.80630.20540.24730.045*
C341.0500 (3)0.2416 (2)0.21276 (10)0.0438 (5)
H341.00240.30740.18060.053*
C351.2341 (3)0.20623 (19)0.21994 (11)0.0467 (6)
H351.31420.24700.19230.056*
C361.3030 (3)0.11236 (19)0.26684 (11)0.0454 (6)
H361.43090.08810.27190.054*
C371.1874 (3)0.05337 (18)0.30651 (10)0.0358 (5)
H371.2363−0.01110.33940.043*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0398 (8)0.0418 (8)0.0372 (8)−0.0120 (7)0.0141 (6)−0.0062 (7)
N10.0369 (10)0.0355 (9)0.0299 (8)−0.0082 (7)0.0094 (7)−0.0015 (7)
N20.0344 (9)0.0379 (9)0.0311 (8)−0.0100 (8)0.0139 (7)−0.0040 (8)
C10.0326 (11)0.0290 (10)0.0281 (10)−0.0032 (8)0.0076 (8)0.0052 (8)
C20.0331 (11)0.0289 (11)0.0278 (10)−0.0029 (9)0.0071 (8)0.0012 (9)
C30.0306 (11)0.0313 (11)0.0285 (10)0.0012 (8)0.0093 (8)0.0027 (8)
C40.0315 (11)0.0336 (11)0.0293 (10)−0.0036 (9)0.0100 (8)0.0014 (9)
C110.0364 (12)0.0327 (11)0.0254 (9)−0.0034 (9)0.0064 (8)0.0064 (9)
C120.0373 (12)0.0382 (12)0.0336 (11)−0.0028 (9)0.0088 (9)0.0027 (10)
C130.0497 (14)0.0344 (12)0.0340 (11)−0.0034 (10)0.0034 (10)0.0020 (9)
C140.0464 (13)0.0354 (12)0.0326 (11)−0.0070 (10)−0.0028 (9)0.0077 (9)
C150.0336 (12)0.0472 (13)0.0420 (12)−0.0084 (10)0.0019 (9)0.0116 (11)
C160.0395 (13)0.0390 (12)0.0341 (11)−0.0023 (10)0.0087 (9)0.0041 (9)
C170.0584 (16)0.0471 (14)0.0534 (14)−0.0177 (11)−0.0058 (11)0.0017 (11)
C310.0388 (12)0.0403 (12)0.0307 (10)−0.0067 (9)0.0119 (9)−0.0046 (9)
C320.0354 (12)0.0307 (11)0.0227 (9)−0.0041 (8)0.0085 (8)−0.0046 (8)
C330.0390 (12)0.0408 (12)0.0328 (11)0.0043 (9)0.0056 (9)−0.0016 (9)
C340.0649 (16)0.0374 (12)0.0303 (11)−0.0026 (11)0.0111 (10)0.0051 (9)
C350.0588 (16)0.0452 (13)0.0422 (12)−0.0158 (11)0.0257 (11)−0.0073 (11)
C360.0353 (13)0.0461 (13)0.0575 (14)−0.0009 (10)0.0162 (11)−0.0041 (12)
C370.0368 (12)0.0366 (12)0.0349 (11)0.0014 (9)0.0087 (9)0.0002 (9)

Geometric parameters (Å, °)

O1—C21.243 (2)C16—H160.9500
N1—C11.308 (2)C17—H17A0.9800
N1—N21.3515 (19)C17—H17B0.9800
N2—C21.350 (2)C17—H17C0.9800
N2—H20.8800C17—H17D0.9800
C1—C41.422 (2)C17—H17E0.9800
C1—C111.478 (2)C17—H17F0.9800
C2—C31.440 (2)C31—C321.500 (2)
C3—C41.341 (2)C31—H31A0.9900
C3—C311.506 (2)C31—H31B0.9900
C4—H40.9500C32—C371.376 (3)
C11—C161.383 (3)C32—C331.376 (2)
C11—C121.392 (2)C33—C341.377 (3)
C12—C131.381 (2)C33—H330.9500
C12—H120.9500C34—C351.369 (3)
C13—C141.381 (3)C34—H340.9500
C13—H130.9500C35—C361.368 (3)
C14—C151.384 (3)C35—H350.9500
C14—C171.500 (3)C36—C371.369 (3)
C15—C161.387 (2)C36—H360.9500
C15—H150.9500C37—H370.9500
C1—N1—N2116.10 (15)C14—C17—H17D109.5
C2—N2—N1127.66 (15)H17A—C17—H17D141.1
C2—N2—H2116.2H17B—C17—H17D56.3
N1—N2—H2116.2H17C—C17—H17D56.3
N1—C1—C4121.77 (17)C14—C17—H17E109.5
N1—C1—C11116.46 (16)H17A—C17—H17E56.3
C4—C1—C11121.76 (16)H17B—C17—H17E141.1
O1—C2—N2120.52 (16)H17C—C17—H17E56.3
O1—C2—C3124.21 (16)H17D—C17—H17E109.5
N2—C2—C3115.27 (16)C14—C17—H17F109.5
C4—C3—C2118.24 (16)H17A—C17—H17F56.3
C4—C3—C31125.03 (17)H17B—C17—H17F56.3
C2—C3—C31116.72 (16)H17C—C17—H17F141.1
C3—C4—C1120.96 (17)H17D—C17—H17F109.5
C3—C4—H4119.5H17E—C17—H17F109.5
C1—C4—H4119.5C32—C31—C3114.42 (15)
C16—C11—C12118.29 (17)C32—C31—H31A108.7
C16—C11—C1120.67 (17)C3—C31—H31A108.7
C12—C11—C1121.03 (17)C32—C31—H31B108.7
C13—C12—C11120.87 (18)C3—C31—H31B108.7
C13—C12—H12119.6H31A—C31—H31B107.6
C11—C12—H12119.6C37—C32—C33118.48 (17)
C14—C13—C12121.16 (19)C37—C32—C31121.19 (17)
C14—C13—H13119.4C33—C32—C31120.33 (17)
C12—C13—H13119.4C32—C33—C34120.83 (18)
C13—C14—C15117.75 (18)C32—C33—H33119.6
C13—C14—C17121.70 (19)C34—C33—H33119.6
C15—C14—C17120.6 (2)C35—C34—C33119.65 (19)
C14—C15—C16121.71 (19)C35—C34—H34120.2
C14—C15—H15119.1C33—C34—H34120.2
C16—C15—H15119.1C36—C35—C34120.14 (19)
C11—C16—C15120.20 (18)C36—C35—H35119.9
C11—C16—H16119.9C34—C35—H35119.9
C15—C16—H16119.9C35—C36—C37119.89 (19)
C14—C17—H17A109.5C35—C36—H36120.1
C14—C17—H17B109.5C37—C36—H36120.1
H17A—C17—H17B109.5C36—C37—C32121.01 (19)
C14—C17—H17C109.5C36—C37—H37119.5
H17A—C17—H17C109.5C32—C37—H37119.5
H17B—C17—H17C109.5
C1—N1—N2—C20.8 (3)C12—C13—C14—C15−0.9 (3)
N2—N1—C1—C4−0.1 (2)C12—C13—C14—C17179.75 (17)
N2—N1—C1—C11178.59 (14)C13—C14—C15—C161.0 (3)
N1—N2—C2—O1179.62 (16)C17—C14—C15—C16−179.62 (17)
N1—N2—C2—C3−0.9 (3)C12—C11—C16—C15−0.9 (3)
O1—C2—C3—C4179.72 (16)C1—C11—C16—C15179.14 (16)
N2—C2—C3—C40.3 (2)C14—C15—C16—C11−0.1 (3)
O1—C2—C3—C310.8 (3)C4—C3—C31—C32−14.1 (3)
N2—C2—C3—C31−178.64 (15)C2—C3—C31—C32164.73 (16)
C2—C3—C4—C10.3 (3)C3—C31—C32—C3790.5 (2)
C31—C3—C4—C1179.16 (17)C3—C31—C32—C33−89.3 (2)
N1—C1—C4—C3−0.5 (3)C37—C32—C33—C340.6 (3)
C11—C1—C4—C3−179.06 (16)C31—C32—C33—C34−179.63 (17)
N1—C1—C11—C16153.12 (17)C32—C33—C34—C350.3 (3)
C4—C1—C11—C16−28.2 (3)C33—C34—C35—C36−0.7 (3)
N1—C1—C11—C12−26.8 (2)C34—C35—C36—C370.2 (3)
C4—C1—C11—C12151.86 (17)C35—C36—C37—C320.7 (3)
C16—C11—C12—C131.0 (2)C33—C32—C37—C36−1.1 (3)
C1—C11—C12—C13−179.02 (16)C31—C32—C37—C36179.14 (17)
C11—C12—C13—C14−0.1 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N2—H2···O1i0.881.892.7686 (19)178
C34—H34···O1ii0.952.573.512 (2)169

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BG2256).

References

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