organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

(4Z)-4-[(2E)-1-Hydr­­oxy-3-(4-meth­oxy­phen­yl)prop-2-en­yl­idene]-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one

aInstitute of Chemistry, University of the Punjab, New Campus, Lahore, Pakistan
*Correspondence e-mail: munawaralimunawar@yahoo.com

(Received 7 October 2009; accepted 3 November 2009; online 11 November 2009)

The title compound, C20H18N2O4, is a chalcone derivative of pyrazole. The pyrazole ring is inclined at a dihedral angle of 19.29 (12)° to the methoxy­phenyl ring mean plane, and by 1.19 (13)° to the phenyl ring. The mol­ecular structure is stabilized by an intra­molecular O—H⋯O hydrogen bond, making an almost planar (r.m.s. deviation = 0.0243 Å) six membered ring.

Related literature

For the anti­microbial activity of chalcones, see: Mityurina1 et al. (1981[Mityurina1, K. V., Kulikova1, L. K., Krasheninnikova1, M. K., & Kharchenko1, V. G. (1981). Pharm. Chem. J. 15, 861-863.]). For the syntheses of chalcones, see: Konieczny et al. (2007[Konieczny, T. M., Konieczny, W., Sabisz, M., Skladanowski, A., Wakiec, R., Augustynowicz-Kopec, E. & Zwolska, Z. (2007). Eur. J. Med. Chem. 65, 729-733.]). For a heterocyclic chalcone, see: Arshad et al. (2008[Arshad, M. N., Tahir, M. N., Asghar, M. N., Khan, I. U. & Ashfaq, M. (2008). Acta Cryst. E64, o1413.]). For details concerning graphset analysis, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C20H18N2O3

  • Mr = 334.36

  • Monoclinic, C c

  • a = 5.0803 (2) Å

  • b = 22.7645 (9) Å

  • c = 14.5880 (6) Å

  • β = 97.626 (2)°

  • V = 1672.19 (12) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 296 K

  • 0.33 × 0.24 × 0.18 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2001[Bruker (2001). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.971, Tmax = 0.984

  • 9137 measured reflections

  • 2056 independent reflections

  • 2628 reflections with I > 2σ(I)

  • Rint = 0.027

Refinement
  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.094

  • S = 1.05

  • 2056 reflections

  • 229 parameters

  • 2 restraints

  • H-atom parameters constrained

  • Δρmax = 0.10 e Å−3

  • Δρmin = −0.16 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2O⋯O1 0.82 1.77 2.529 (3) 153

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information


Comment top

Pyranopyrazole derivatives have been reported as being antimicrobial agents (Mityurina1 et al., 1981). The title compound is a heterocyclic chalcone (Arshad et al., 2008), and was synthesized as we are interested in the synthesis of pyranopyrazole derivatives.

The molecular structure of the title compound is illustrated in Fig. 1, and the geometrical parameters are available in the archived CIF. The title molecule, besides the methoxy phenyl ring A (C13-C18) attached to the pyrazole ring, is almost planar. The dihedral angle between the pyrazole ring B (N1/N2/C10-C12) and phenyl ring A is 19.29 (12) °. Phenyl ring C (C1-C6) lies in the plane of the pyrazole ring B, with a dihedral angle of 1.19 (13)°. There is an intramolecular O-H···O hydrogen bond stabilizing the molecule (Fig. 1 and Table 1). It forms a six membered ring motif which can be described as S(6) (Bernstein, et al., 1995).

Related literature top

For the antimicrobial activity of chalcones, see: Mityurina1 et al. (1981). For the syntheses of chalcones, see: Konieczny et al. (2007). For a hereocyclic chalcone, see: Arshad et al. (2008). For details concerning graphset analysis, see: Bernstein et al. (1995).

Experimental top

The title compound was prepared according to the literature method (Konieczny et al., 2007). 1 mmol (0.216 g) of 3-methyl-1-phenyl-acetyl-5-hydroxy pyrazole and 1.5 mmol (0.204 g) of 4-methoxybenzaldehyde was added to the mixture of 2 ml of glacial acetic acid and 0.2 ml of concentrated sulfuric acid and heated at 353-358 K for 9 h with stirring. The progress of the reaction was followed by TLC. On completion, the mixture was added to ice cold water. The precipitate obtained was filtered off, washed with methanol and purified by column chromatography using n-hexane:ethyl acetate(3:2). Red needle-like crystals, suitable for X-ray analysis, were obtained by slow evaporation of a solution in chloroform at r.t.

Refinement top

In the final cycles of refinement, in the absence of significant anomalous scattering effects, 672 Friedel pairs were merged and Δf " set to zero. The H-atoms were included in calculated positions and treated as riding: C—H = 0.93 Å for aromatic, C–H = 0.96 Å for CH3 and O—H = 0.82 Å, with Uiso(H) = k × Ueq(parent C- or O-atom), where k = 1.2 for aromatic H-atoms and 1.5Ueq(parent O-atom, and methyl C-atoms).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with thermal ellipsoids drawn at the 50% probability level. The intramolecular O-H···O hydrogen bond is shown as a dashed line.
(4Z)-4-[(2E)-1-Hydroxy-3-(4-methoxyphenyl)prop-2-enylidene]-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one top
Crystal data top
C20H18N2O3F(000) = 704
Mr = 334.36Dx = 1.328 Mg m3
Monoclinic, CcMo Kα radiation, λ = 0.71073 Å
Hall symbol: C -2ycCell parameters from 3228 reflections
a = 5.0803 (2) Åθ = 2.3–25.8°
b = 22.7645 (9) ŵ = 0.09 mm1
c = 14.5880 (6) ÅT = 296 K
β = 97.626 (2)°Needle, red
V = 1672.19 (12) Å30.33 × 0.24 × 0.18 mm
Z = 4
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2056 independent reflections
Radiation source: fine-focus sealed tube2628 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.027
ϕ and ω scansθmax = 28.3°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
h = 66
Tmin = 0.971, Tmax = 0.984k = 3030
9137 measured reflectionsl = 1818
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.094H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0492P)2 + 0.0958P]
where P = (Fo2 + 2Fc2)/3
2056 reflections(Δ/σ)max < 0.001
229 parametersΔρmax = 0.10 e Å3
2 restraintsΔρmin = 0.16 e Å3
Crystal data top
C20H18N2O3V = 1672.19 (12) Å3
Mr = 334.36Z = 4
Monoclinic, CcMo Kα radiation
a = 5.0803 (2) ŵ = 0.09 mm1
b = 22.7645 (9) ÅT = 296 K
c = 14.5880 (6) Å0.33 × 0.24 × 0.18 mm
β = 97.626 (2)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2056 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
2628 reflections with I > 2σ(I)
Tmin = 0.971, Tmax = 0.984Rint = 0.027
9137 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0372 restraints
wR(F2) = 0.094H-atom parameters constrained
S = 1.05Δρmax = 0.10 e Å3
2056 reflectionsΔρmin = 0.16 e Å3
229 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles

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
xyzUiso*/Ueq
O10.0176 (4)0.44681 (8)0.51341 (14)0.0664 (7)
O20.3841 (4)0.46097 (8)0.63360 (16)0.0711 (7)
O31.6238 (3)0.37711 (9)1.04514 (13)0.0698 (7)
N10.1696 (3)0.34974 (9)0.51051 (14)0.0509 (7)
N20.0989 (4)0.29740 (9)0.55796 (15)0.0553 (7)
C11.0015 (4)0.41049 (11)0.83769 (17)0.0485 (7)
C21.0508 (5)0.35476 (12)0.8761 (2)0.0582 (9)
C31.2597 (5)0.34518 (11)0.9444 (2)0.0596 (9)
C41.4271 (4)0.39123 (12)0.97629 (17)0.0525 (8)
C51.3838 (4)0.44665 (10)0.93893 (17)0.0493 (8)
C61.1739 (4)0.45543 (11)0.87062 (17)0.0503 (8)
C70.7813 (4)0.42297 (12)0.76621 (17)0.0509 (8)
C80.5954 (4)0.38652 (12)0.72645 (17)0.0520 (8)
C90.3848 (4)0.40523 (12)0.65663 (17)0.0520 (8)
C100.1866 (4)0.36961 (11)0.61184 (16)0.0476 (7)
C110.1116 (4)0.30908 (11)0.61679 (17)0.0499 (8)
C120.0042 (4)0.39408 (11)0.54131 (16)0.0508 (8)
C130.3813 (4)0.34899 (10)0.43652 (17)0.0495 (8)
C140.5624 (5)0.30347 (11)0.43192 (19)0.0546 (8)
C150.7691 (5)0.30167 (13)0.3600 (2)0.0689 (10)
C160.7933 (6)0.34472 (14)0.2929 (2)0.0789 (11)
C170.6134 (6)0.38955 (15)0.2983 (2)0.0745 (11)
C180.4058 (5)0.39282 (13)0.3700 (2)0.0646 (10)
C191.8035 (5)0.42227 (14)1.0791 (2)0.0716 (10)
C200.2392 (5)0.26103 (12)0.6752 (2)0.0690 (10)
H20.940400.323600.855100.0700*
H2O0.253800.467900.595600.1070*
H31.289400.307800.969300.0720*
H51.495300.477600.959700.0590*
H61.146000.492800.845500.0600*
H70.768500.461600.745400.0610*
H80.601800.347300.744500.0620*
H140.545500.274200.476900.0650*
H150.892400.271300.356900.0830*
H160.931300.343200.244200.0950*
H170.630500.418500.252900.0890*
H180.285500.423800.373500.0770*
H19A1.879800.439501.028600.1080*
H19B1.942100.406001.122900.1080*
H19C1.710300.451901.108800.1080*
H20A0.141800.225200.661500.1040*
H20B0.239900.270800.739200.1040*
H20C0.418500.255900.662600.1040*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0690 (11)0.0494 (10)0.0744 (13)0.0022 (9)0.0138 (9)0.0081 (9)
O20.0694 (11)0.0573 (11)0.0793 (14)0.0111 (9)0.0170 (10)0.0090 (10)
O30.0580 (10)0.0666 (12)0.0776 (13)0.0102 (9)0.0174 (9)0.0148 (10)
N10.0482 (10)0.0453 (12)0.0552 (13)0.0029 (8)0.0083 (9)0.0015 (9)
N20.0576 (11)0.0460 (11)0.0581 (13)0.0010 (9)0.0075 (10)0.0045 (10)
C10.0451 (11)0.0504 (13)0.0490 (14)0.0043 (10)0.0021 (10)0.0069 (11)
C20.0532 (13)0.0502 (14)0.0680 (17)0.0098 (11)0.0042 (12)0.0042 (13)
C30.0554 (13)0.0447 (13)0.0749 (18)0.0041 (11)0.0053 (13)0.0066 (13)
C40.0452 (12)0.0557 (15)0.0550 (15)0.0021 (11)0.0012 (11)0.0037 (12)
C50.0464 (12)0.0465 (13)0.0527 (14)0.0076 (10)0.0014 (10)0.0036 (11)
C60.0510 (11)0.0453 (13)0.0529 (15)0.0055 (10)0.0005 (11)0.0022 (11)
C70.0465 (13)0.0520 (14)0.0521 (15)0.0015 (10)0.0010 (10)0.0000 (12)
C80.0477 (12)0.0537 (15)0.0529 (15)0.0022 (10)0.0007 (11)0.0045 (11)
C90.0479 (12)0.0563 (15)0.0510 (15)0.0013 (10)0.0038 (11)0.0039 (11)
C100.0428 (11)0.0498 (13)0.0483 (14)0.0020 (10)0.0012 (10)0.0018 (11)
C110.0490 (12)0.0469 (13)0.0511 (14)0.0014 (10)0.0038 (10)0.0008 (11)
C120.0505 (12)0.0450 (14)0.0550 (16)0.0021 (10)0.0003 (11)0.0002 (11)
C130.0448 (12)0.0528 (14)0.0484 (14)0.0112 (10)0.0027 (10)0.0070 (11)
C140.0518 (13)0.0520 (14)0.0560 (15)0.0073 (11)0.0073 (11)0.0062 (12)
C150.0585 (14)0.0662 (17)0.075 (2)0.0023 (12)0.0167 (13)0.0126 (15)
C160.0740 (18)0.077 (2)0.074 (2)0.0172 (16)0.0334 (16)0.0075 (17)
C170.0805 (18)0.072 (2)0.0643 (19)0.0138 (16)0.0156 (15)0.0063 (15)
C180.0625 (16)0.0652 (18)0.0615 (17)0.0041 (13)0.0082 (13)0.0047 (14)
C190.0574 (14)0.081 (2)0.0697 (18)0.0097 (14)0.0168 (13)0.0025 (16)
C200.0720 (17)0.0543 (16)0.0721 (18)0.0016 (13)0.0225 (14)0.0081 (14)
Geometric parameters (Å, º) top
O1—C121.266 (3)C13—C141.381 (3)
O2—C91.313 (3)C14—C151.383 (4)
O3—C41.358 (3)C15—C161.379 (4)
O3—C191.420 (3)C16—C171.365 (5)
O2—H2O0.8200C17—C181.385 (4)
N1—N21.401 (3)C2—H20.9300
N1—C131.419 (3)C3—H30.9300
N1—C121.352 (3)C5—H50.9300
N2—C111.307 (3)C6—H60.9300
C1—C21.396 (4)C7—H70.9300
C1—C71.453 (3)C8—H80.9300
C1—C61.390 (3)C14—H140.9300
C2—C31.373 (4)C15—H150.9300
C3—C41.391 (4)C16—H160.9300
C4—C51.380 (4)C17—H170.9300
C5—C61.374 (3)C18—H180.9300
C7—C81.331 (3)C19—H19A0.9600
C8—C91.440 (3)C19—H19B0.9600
C9—C101.387 (3)C19—H19C0.9600
C10—C111.434 (3)C20—H20A0.9600
C10—C121.430 (3)C20—H20B0.9600
C11—C201.482 (4)C20—H20C0.9600
C13—C181.386 (4)
C4—O3—C19117.6 (2)C16—C17—C18121.4 (3)
C9—O2—H2O109.00C13—C18—C17118.6 (3)
N2—N1—C12111.33 (18)C1—C2—H2119.00
N2—N1—C13118.97 (19)C3—C2—H2119.00
C12—N1—C13129.6 (2)C2—C3—H3120.00
N1—N2—C11106.58 (19)C4—C3—H3120.00
C2—C1—C6117.3 (2)C4—C5—H5120.00
C6—C1—C7119.6 (2)C6—C5—H5120.00
C2—C1—C7123.1 (2)C1—C6—H6119.00
C1—C2—C3121.1 (2)C5—C6—H6119.00
C2—C3—C4120.2 (2)C1—C7—H7116.00
O3—C4—C3115.2 (2)C8—C7—H7116.00
O3—C4—C5124.9 (2)C7—C8—H8119.00
C3—C4—C5119.9 (2)C9—C8—H8119.00
C4—C5—C6119.1 (2)C13—C14—H14120.00
C1—C6—C5122.4 (2)C15—C14—H14120.00
C1—C7—C8128.7 (2)C14—C15—H15120.00
C7—C8—C9122.8 (2)C16—C15—H15120.00
O2—C9—C8116.3 (2)C15—C16—H16120.00
O2—C9—C10117.9 (2)C17—C16—H16120.00
C8—C9—C10125.8 (2)C16—C17—H17119.00
C9—C10—C11136.0 (2)C18—C17—H17119.00
C9—C10—C12119.5 (2)C13—C18—H18121.00
C11—C10—C12104.56 (19)C17—C18—H18121.00
N2—C11—C20119.0 (2)O3—C19—H19A110.00
C10—C11—C20129.7 (2)O3—C19—H19B109.00
N2—C11—C10111.2 (2)O3—C19—H19C109.00
O1—C12—N1126.6 (2)H19A—C19—H19B109.00
N1—C12—C10106.3 (2)H19A—C19—H19C109.00
O1—C12—C10127.1 (2)H19B—C19—H19C109.00
N1—C13—C14118.6 (2)C11—C20—H20A109.00
C14—C13—C18120.6 (2)C11—C20—H20B109.00
N1—C13—C18120.8 (2)C11—C20—H20C109.00
C13—C14—C15119.5 (2)H20A—C20—H20B110.00
C14—C15—C16120.3 (3)H20A—C20—H20C109.00
C15—C16—C17119.6 (3)H20B—C20—H20C109.00
C19—O3—C4—C3178.9 (2)C4—C5—C6—C10.3 (4)
C19—O3—C4—C52.2 (3)C1—C7—C8—C9179.2 (2)
C12—N1—N2—C111.0 (3)C7—C8—C9—C10179.4 (2)
C13—N1—N2—C11175.09 (19)C7—C8—C9—O20.1 (4)
N2—N1—C12—C100.6 (2)O2—C9—C10—C11178.3 (3)
C13—N1—C12—C10174.9 (2)C8—C9—C10—C12177.7 (2)
N2—N1—C13—C1420.3 (3)O2—C9—C10—C121.8 (3)
C12—N1—C13—C14164.5 (2)C8—C9—C10—C112.3 (4)
N2—N1—C13—C18159.5 (2)C12—C10—C11—C20178.0 (2)
C12—N1—C13—C1815.8 (4)C9—C10—C12—O10.5 (4)
N2—N1—C12—O1178.9 (2)C9—C10—C12—N1179.9 (2)
C13—N1—C12—O15.5 (4)C11—C10—C12—O1179.5 (2)
N1—N2—C11—C20177.8 (2)C11—C10—C12—N10.1 (2)
N1—N2—C11—C100.9 (3)C9—C10—C11—N2179.5 (3)
C7—C1—C2—C3179.2 (2)C9—C10—C11—C202.0 (5)
C2—C1—C6—C50.8 (4)C12—C10—C11—N20.5 (3)
C6—C1—C2—C30.7 (4)N1—C13—C14—C15179.5 (2)
C6—C1—C7—C8179.5 (2)C18—C13—C14—C150.2 (4)
C2—C1—C7—C80.4 (4)N1—C13—C18—C17178.9 (2)
C7—C1—C6—C5179.2 (2)C14—C13—C18—C170.8 (4)
C1—C2—C3—C40.2 (4)C13—C14—C15—C160.5 (4)
C2—C3—C4—C50.3 (4)C14—C15—C16—C170.7 (4)
C2—C3—C4—O3178.7 (2)C15—C16—C17—C180.0 (5)
O3—C4—C5—C6178.7 (2)C16—C17—C18—C130.7 (4)
C3—C4—C5—C60.2 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2O···O10.821.772.529 (3)153
C7—H7···O20.932.372.743 (3)104
C14—H14···N20.932.472.792 (3)100
C18—H18···O10.932.362.947 (3)121

Experimental details

Crystal data
Chemical formulaC20H18N2O3
Mr334.36
Crystal system, space groupMonoclinic, Cc
Temperature (K)296
a, b, c (Å)5.0803 (2), 22.7645 (9), 14.5880 (6)
β (°) 97.626 (2)
V3)1672.19 (12)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.33 × 0.24 × 0.18
Data collection
DiffractometerBruker Kappa APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2001)
Tmin, Tmax0.971, 0.984
No. of measured, independent and
observed [I > 2σ(I)] reflections
9137, 2056, 2628
Rint0.027
(sin θ/λ)max1)0.666
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.094, 1.05
No. of reflections2056
No. of parameters229
No. of restraints2
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.10, 0.16

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2O···O10.821.772.529 (3)153
 

Acknowledgements

KIM acknowledges the Institute of Chemistry, University of the Punjab, for providing research facilities, and the Education Department, Government of the Punjab, for their co-operation.

References

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