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Acta Crystallogr Sect E Struct Rep Online. 2010 December 1; 66(Pt 12): o3215–o3216.
Published online 2010 November 17. doi:  10.1107/S1600536810046428
PMCID: PMC3011398

6-(Adamantan-1-yl)-3-(3-fluoro­phen­yl)-1,2,4-triazolo[3,4-b][1,3,4]thia­diazole

Abstract

The title mol­ecule, C19H19FN4S, displays C s mol­ecular symmetry, in which the crystallographic mirror plane bis­ects the adamantan-1-yl unit while the 3-fluoro­phenyl triazole ring is located on the mirror plane. The F atom of the 3-fluoro­phenyl ring is positionally disordered [occupancy ratio 0.9:0.1]. In the crystal, π–π inter­actions between the triazole and phenyl rings occur [centroid–centroid distance = 3.5849 (7) Å] and weak C—H(...)F inter­actions form a ribbon propagating in [010].

Related literature

For the biological significance of fused heterocycles, see: Khan et al. (2010a [triangle],b [triangle]); Demirbas et al. (2005 [triangle]); Amir et al. (2007 [triangle]); Ashok et al. (2007 [triangle]); Palekar et al. (2009 [triangle]); Serwar et al. (2009 [triangle]); Akhtar et al. (2007 [triangle], 2008a [triangle],b [triangle]). For the activity of adamantyl derivatives, see: Kadi et al. (2007 [triangle]); Kouatly et al. (2009 [triangle]); Zahid et al. (2009 [triangle]). For a related structure, see: Khan et al. (2009 [triangle]). For standard bond lengths, see: Allen et al. (1987 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o3215-scheme1.jpg

Experimental

Crystal data

  • C19H19FN4S
  • M r = 354.44
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o3215-efi2.jpg
  • a = 11.6385 (16) Å
  • b = 6.6555 (5) Å
  • c = 11.6634 (16) Å
  • β = 117.379 (14)°
  • V = 802.25 (17) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.22 mm−1
  • T = 173 K
  • 0.34 × 0.30 × 0.11 mm

Data collection

  • Stoe IPDS-2 diffractometer
  • 6164 measured reflections
  • 1708 independent reflections
  • 1223 reflections with I > 2σ(I)
  • R int = 0.031

Refinement

  • R[F 2 > 2σ(F 2)] = 0.030
  • wR(F 2) = 0.074
  • S = 0.95
  • 1708 reflections
  • 154 parameters
  • 4 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.20 e Å−3
  • Δρmin = −0.26 e Å−3

Data collection: X-AREA (Stoe & Cie, 2006 [triangle]); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2006 [triangle]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: PLATON (Spek, 2009 [triangle]) and Mercury (Macrae et al., 2006 [triangle]); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008 [triangle]), PLATON and publCIF (Westrip, 2010 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810046428/kp2286sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810046428/kp2286Isup2.hkl

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

Acknowledgments

HSE thanks the staff of the X-ray Application Lab of the CSEM, Neuchâtel, for access to the X-ray diffraction equipment.

supplementary crystallographic information

Comment

Fused heterocycles have received widespread attention in the recent years due to their outstanding biological applications [Khan et al. 2010a; Demirbas et al., 2005; Amir et al., 2007; Ashok et al., 2007; Palekar et al., 2009]. Moreover, compounds bearing an adamantyl moiety are gaining prominence due to their biological and pharmaceutical potential [Kadi et al., 2007; Kouatly et al., 2009; Zahid et al., 2009]. The title compound was synthesised in continuation of our previous studies on the synthesis and biological screening of five membered heterocycles [Akhtar et al., 2007, 2008a, 2008b; Serwar et al.,2009; Khan et al., 2009, 2010b].

Bond distances (Allen et al., 1987) and bond angles are normal and similar to those reported for the 2-fluorophenyl derivative (Khan et al., 2009). The 3-fluorophenyl moiety is positionally disordered, with atom F1 having occupancies of 0.45/0.05 (F1A/F1B), where F1A is bonded to atom C6, while atom F1B is bonded to atom C8 (Fig. 1).

The title molecule possesses crystallographic mirror symmetry; the mirror plane bisects the adamantane moiety while the rest of the molecule lies in the mirror plane. The 3-fluorophenyl moiety is positionally disordered. The 2-fluorophenyl derivative, however, crystallised in the orthorhombic space group Pbca and the molecule possess no crystallographic symmetry. The 2-fluorophenyl ring is inclined to the triazole ring by 48.6 (1)°, to eliviate steric hindrance.

In the crystal of the title compound there are weak C—H···F interactions [C11—H11A···F1Ai, H···F 2.67 Å, C—H···F 145 °, symmetry code (i) -x, y + 1/2, -z + 2)] leading to the formation of a one-dimensional ribbon-like structure running in [010] (Fig. 2). There are also π–π interactions with the centroid-to centroid distance between the mean planes of the triazole ring (N2,C2,N3,N4,C3) and symmetry related phenyl rings (C4—C9) being 3.5849 (7) Å [the perpendicular distance is 3.3278 (1) Å with a slippage of 1.333 Å].

Experimental

A mixture of 4-amino-5-(3-fluorophenyl)-2H-1,2,4-triazole-3(4H)-thione (0.2 g, 0.56 mmol) and adamantane-1-carboxylic acid (0.10 g, 0.56 mmol) was refluxed in the presence of POCl3 (5.0 mL) for 4 h [Khan et al. 2010a]. The reaction mixture was cooled to RT, poured into crushed ice and neutralized using solid potassium carbonate until pH 8. The precipitated solid was filtered off, washed with excess water and recrystallised from chloroform to give colourless plate-like crystals, suitable for X-ray analysis.

Refinement

A region of electron denstiy was located near atom C8 indicating a positional disorder of the 3-fluorophenyl moiety. In the final cycles of least-squares refinement atom F1 was split to give F1a (occupancy 0.45) bonded to atom C6 and atom F1b (occupancy 0.05) bonded to atom C8. Bond length C8—F1b was refined with a distance restraint of 1.36 (2) Å. H-atoms H6a, H8b and H7 were refined with distance restraints of 0.95 (2) A% with Uiso(H) = 1.2Ueq(C). The remaining H-atoms were included in calculated positions and treated as riding atoms: C—H = 0.95, 0.99, and 1.00 Å for CH-aromatic, CH2 and CH-methine H-atoms, respectively, with Uiso(H) = 1.2Ueq(parent C-atom).

Figures

Fig. 1.
A view of the molecular structure of the title molecule with the displacement ellipsoids drawn at the 50% probability level [symmetry code (a) = x, 3/2 - y, z; The positional disorder of the 3-fluorophenyl group is also illustrated: atoms F1A and H8A ...
Fig. 2.
The crystal packing of the title compound along the a axis. The C—H···F interactions are shown as dashed cyan lines.

Crystal data

C19H19FN4SF(000) = 372
Mr = 354.44Dx = 1.467 Mg m3
Monoclinic, P21/mMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybCell parameters from 4261 reflections
a = 11.6385 (16) Åθ = 3.1–26.0°
b = 6.6555 (5) ŵ = 0.22 mm1
c = 11.6634 (16) ÅT = 173 K
β = 117.379 (14)°Plate, colourless
V = 802.25 (17) Å30.34 × 0.30 × 0.11 mm
Z = 2

Data collection

Stoe IPDS-2 diffractometer1223 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.031
graphiteθmax = 26.1°, θmin = 3.4°
[var phi] and ω scansh = −14→14
6164 measured reflectionsk = −7→8
1708 independent reflectionsl = −14→14

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)] = 0.030Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.074H atoms treated by a mixture of independent and constrained refinement
S = 0.95w = 1/[σ2(Fo2) + (0.0449P)2] where P = (Fo2 + 2Fc2)/3
1708 reflections(Δ/σ)max = 0.001
154 parametersΔρmax = 0.20 e Å3
4 restraintsΔρmin = −0.26 e Å3

Special details

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 e.s.d.'s 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 > 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)
S10.42509 (5)0.750000.98501 (5)0.0307 (2)
F1A−0.2195 (2)0.750001.1429 (2)0.0500 (6)0.900
N10.17319 (15)0.750000.85412 (15)0.0251 (5)
N20.20898 (15)0.750000.98446 (16)0.0243 (5)
N30.35605 (17)0.750001.18934 (17)0.0325 (6)
N40.23242 (17)0.750001.18047 (16)0.0311 (6)
C10.27709 (18)0.750000.84027 (19)0.0249 (6)
C20.33636 (19)0.750001.06956 (19)0.0268 (6)
C30.14499 (19)0.750001.05806 (19)0.0257 (6)
C40.00535 (19)0.750001.0101 (2)0.0248 (6)
C5−0.0419 (2)0.750001.1000 (2)0.0318 (7)
C6−0.1732 (2)0.750001.0556 (2)0.0342 (7)
C7−0.2599 (2)0.750000.9272 (2)0.0378 (8)
C8−0.2117 (2)0.750000.8390 (2)0.0367 (8)
C9−0.08020 (19)0.750000.8790 (2)0.0299 (7)
C100.27522 (18)0.750000.71113 (18)0.0254 (6)
C110.34448 (16)0.9374 (3)0.69694 (15)0.0362 (5)
C120.34071 (17)0.9366 (3)0.56371 (15)0.0413 (6)
C130.20148 (17)0.9360 (3)0.45854 (15)0.0428 (6)
C140.1337 (2)0.750000.4720 (2)0.0382 (8)
C150.1355 (2)0.750000.6040 (2)0.0368 (7)
C160.4093 (2)0.750000.5501 (2)0.0441 (9)
F1B−0.2859 (18)0.750000.7166 (11)0.052 (5)0.100
H7−0.3504 (11)0.750000.902 (2)0.0450*
H8A−0.276 (4)0.750000.7516 (18)0.0440*0.900
H9−0.048300.750000.817300.0360*
H11A0.301401.059800.706600.0440*
H11B0.435400.938300.765300.0440*
H120.385501.059300.554600.0490*
H50.015500.750001.190000.0380*
H13B0.199300.937100.372700.0510*
H140.042000.750000.402600.0460*
H15A0.089900.870500.612200.0440*0.500
H15B0.089900.629500.612200.0440*0.500
H16A0.408100.750000.464600.0530*
H16B0.500600.750000.617600.0530*
H13A0.156501.057800.465900.0510*
H6B−0.21 (3)0.750001.11 (2)0.0410*0.100

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
S10.0210 (3)0.0411 (4)0.0298 (3)0.00000.0116 (2)0.0000
F1A0.0514 (10)0.0583 (11)0.0639 (12)0.00000.0467 (9)0.0000
N10.0251 (8)0.0263 (10)0.0252 (8)0.00000.0128 (7)0.0000
N20.0218 (8)0.0275 (9)0.0245 (8)0.00000.0115 (6)0.0000
N30.0268 (9)0.0403 (12)0.0291 (9)0.00000.0118 (7)0.0000
N40.0285 (9)0.0371 (12)0.0285 (9)0.00000.0139 (7)0.0000
C10.0219 (9)0.0230 (11)0.0301 (10)0.00000.0123 (8)0.0000
C20.0207 (9)0.0285 (12)0.0289 (10)0.00000.0095 (8)0.0000
C30.0283 (10)0.0249 (12)0.0269 (10)0.00000.0153 (9)0.0000
C40.0260 (10)0.0206 (11)0.0320 (10)0.00000.0169 (9)0.0000
C50.0344 (12)0.0298 (13)0.0361 (11)0.00000.0205 (9)0.0000
C60.0368 (12)0.0282 (12)0.0520 (14)0.00000.0329 (11)0.0000
C70.0270 (11)0.0337 (14)0.0581 (15)0.00000.0243 (11)0.0000
C80.0254 (11)0.0401 (15)0.0414 (13)0.00000.0126 (10)0.0000
C90.0256 (10)0.0336 (13)0.0326 (11)0.00000.0153 (9)0.0000
C100.0217 (10)0.0288 (12)0.0276 (10)0.00000.0131 (8)0.0000
C110.0436 (9)0.0339 (10)0.0359 (8)−0.0108 (7)0.0223 (7)−0.0049 (7)
C120.0535 (10)0.0393 (10)0.0405 (9)−0.0168 (8)0.0298 (8)−0.0033 (7)
C130.0565 (11)0.0416 (11)0.0355 (8)0.0138 (8)0.0257 (8)0.0081 (7)
C140.0291 (11)0.0576 (17)0.0279 (11)0.00000.0132 (9)0.0000
C150.0232 (10)0.0586 (17)0.0290 (10)0.00000.0123 (9)0.0000
C160.0313 (12)0.073 (2)0.0357 (12)0.00000.0220 (10)0.0000
F1B0.030 (7)0.084 (12)0.031 (7)0.00000.006 (7)0.0000

Geometric parameters (Å, °)

S1—C11.773 (2)C10—C151.529 (3)
S1—C21.725 (2)C11—C121.534 (2)
F1A—C61.353 (3)C12—C131.517 (3)
F1B—C81.285 (12)C12—C161.524 (3)
N1—N21.379 (2)C13—C141.514 (3)
N1—C11.292 (3)C14—C151.530 (3)
N2—C31.371 (3)C5—H50.9500
N2—C21.353 (3)C6—H6B0.9 (3)
N3—N41.394 (3)C7—H70.955 (17)
N3—C21.308 (3)C8—H8A0.95 (2)
N4—C31.318 (3)C9—H90.9500
C1—C101.496 (3)C11—H11A0.9900
C3—C41.455 (3)C11—H11B0.9900
C4—C91.389 (3)C12—H121.0000
C4—C51.390 (3)C13—H13A0.9900
C5—C61.370 (4)C13—H13B0.9900
C6—C71.368 (3)C14—H141.0000
C7—C81.380 (3)C15—H15A0.9900
C8—C91.380 (4)C15—H15B0.9900
C10—C111.535 (2)C16—H16A0.9900
C10—C11i1.535 (2)C16—H16B0.9900
C1—S1—C288.25 (11)C13—C14—C13i109.66 (19)
N2—N1—C1108.20 (17)C13i—C14—C15109.73 (12)
N1—N2—C2118.84 (18)C10—C15—C14109.9 (2)
N1—N2—C3135.60 (19)C12—C16—C12i109.20 (19)
C2—N2—C3105.56 (17)C4—C5—H5121.00
N4—N3—C2104.65 (18)C6—C5—H5121.00
N3—N4—C3109.67 (18)C5—C6—H6B122.00
S1—C1—N1115.88 (15)C7—C6—H6B115.00
S1—C1—C10121.10 (17)C6—C7—H7119.4 (13)
N1—C1—C10123.02 (19)C8—C7—H7122.7 (13)
S1—C2—N2108.83 (15)C7—C8—H8A114 (3)
S1—C2—N3138.93 (19)C9—C8—H8A125 (3)
N2—C2—N3112.2 (2)C4—C9—H9120.00
N2—C3—N4107.9 (2)C8—C9—H9120.00
N2—C3—C4126.26 (18)C10—C11—H11A110.00
N4—C3—C4125.9 (2)C10—C11—H11B110.00
C3—C4—C5117.99 (19)C12—C11—H11A110.00
C3—C4—C9122.1 (2)C12—C11—H11B110.00
C5—C4—C9119.9 (2)H11A—C11—H11B108.00
C4—C5—C6118.3 (2)C11—C12—H12109.00
F1A—C6—C5118.5 (2)C13—C12—H12109.00
F1A—C6—C7118.4 (2)C16—C12—H12109.00
C5—C6—C7123.2 (2)C12—C13—H13A110.00
C6—C7—C8117.9 (2)C12—C13—H13B110.00
C7—C8—C9121.1 (2)C14—C13—H13A110.00
F1B—C8—C7122.2 (10)C14—C13—H13B110.00
F1B—C8—C9116.8 (10)H13A—C13—H13B108.00
C4—C9—C8119.6 (2)C13—C14—H14109.00
C1—C10—C11110.08 (11)C15—C14—H14109.00
C1—C10—C15109.90 (19)C13i—C14—H14109.00
C1—C10—C11i110.08 (11)C10—C15—H15A110.00
C11—C10—C15109.02 (11)C10—C15—H15B110.00
C11—C10—C11i108.71 (18)C14—C15—H15A110.00
C11i—C10—C15109.02 (11)C14—C15—H15B110.00
C10—C11—C12109.55 (15)H15A—C15—H15B108.00
C11—C12—C13109.96 (17)C12—C16—H16A110.00
C11—C12—C16109.64 (15)C12—C16—H16B110.00
C13—C12—C16109.24 (16)H16A—C16—H16B108.00
C12—C13—C14109.39 (16)C12i—C16—H16A110.00
C13—C14—C15109.73 (12)C12i—C16—H16B110.00
C2—S1—C1—N10.00 (1)N4—C3—C4—C50.00 (1)
C2—S1—C1—C10180.00 (1)N4—C3—C4—C9180.00 (1)
C1—S1—C2—N20.00 (1)C3—C4—C5—C6180.00 (1)
C1—S1—C2—N3−180.00 (1)C9—C4—C5—C60.00 (1)
C1—N1—N2—C20.00 (1)C3—C4—C9—C8180.00 (1)
C1—N1—N2—C3180.00 (1)C5—C4—C9—C80.00 (1)
N2—N1—C1—S10.00 (1)C4—C5—C6—F1A180.00 (1)
N2—N1—C1—C10180.00 (1)C4—C5—C6—C70.00 (1)
N1—N2—C3—C40.00 (1)F1A—C6—C7—C8180.00 (1)
C3—N2—C2—N30.00 (1)C5—C6—C7—C80.00 (1)
N1—N2—C2—S10.00 (1)C6—C7—C8—C90.00 (1)
C3—N2—C2—S1180.00 (1)C7—C8—C9—C40.00 (1)
N1—N2—C3—N4−180.00 (1)C1—C10—C11—C12−179.45 (16)
C2—N2—C3—C4180.00 (1)C15—C10—C11—C12−58.8 (2)
C2—N2—C3—N40.00 (1)C11i—C10—C11—C1259.90 (19)
N1—N2—C2—N3180.00 (1)C1—C10—C15—C14180.00 (1)
N4—N3—C2—S1180.00 (1)C11—C10—C15—C1459.27 (12)
N4—N3—C2—N20.00 (1)C10—C11—C12—C1359.6 (2)
C2—N3—N4—C30.00 (1)C10—C11—C12—C16−60.5 (2)
N3—N4—C3—C4−180.00 (1)C11—C12—C13—C14−60.1 (2)
N3—N4—C3—N20.00 (1)C16—C12—C13—C1460.2 (2)
N1—C1—C10—C11120.09 (13)C11—C12—C16—C12i60.3 (2)
N1—C1—C10—C150.00 (1)C13—C12—C16—C12i−60.27 (19)
S1—C1—C10—C15180.00 (1)C12—C13—C14—C1560.2 (2)
S1—C1—C10—C11−59.91 (13)C12—C13—C14—C13i−60.4 (2)
N2—C3—C4—C5180.00 (1)C13—C14—C15—C10−60.28 (14)
N2—C3—C4—C90.00 (1)

Symmetry codes: (i) x, −y+3/2, z.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C11—H11A···F1Aii0.992.673.526 (3)145

Symmetry codes: (ii) −x, y+1/2, −z+2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: KP2286).

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