Issue contents
Download PDF of article
Download CIF
3D view
Navigation
Highlighting
Dictionary of Crystallography reference
IUPAC Gold Book reference
more ...
Download citation
FormatBIBTeX
EndNote
RefMan
Refer
Medline
CIF
SGML
Plain Text
share
Previous article
Next article
Previous article
Issue contents
Download PDF of article
Download CIF
3D view
Navigation
Highlighting
Dictionary of Crystallography reference
IUPAC Gold Book reference
more ...
Download citation
FormatBIBTeX
EndNote
RefMan
Refer
Medline
CIF
SGML
Plain Text
share
Next article

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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 70| Part 2| February 2014| Page o136
doi:10.1107/S1600536813034673

Ethyl 6-(4-cyclo­propyl-1H-1,2,3-triazol-1-yl)pyridine-3-carboxyl­ate

Muhammad Naeem Ahmed,a Khawaja Ansar Yasin,a M. Nawaz Tahir,b* Asma Bibic and Hina Andleebc

aDepartment of Chemistry, The University of Azad Jammu and Kashmir, Muzaffarabad 13100, Pakistan, bUniversity of Sargodha, Department of Physics, Sargodha, Pakistan, and cDepartment of Chemistry, Quaid-e-Azam University, Islamabad 45320, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 26 December 2013; accepted 27 December 2013; online 15 January 2014)

In the title compound, C13H14N4O2, which has approximate mirror symmetry, the dihedral angles between the triazole ring and the cyclo­propane and pyridine rings are 87.1 (2) and 7.60 (9)°, respectively. In the crystal, inversion dimers linked by pairs of both C—H⋯N and C—H⋯O inter­actions generate R22(6) and R22(18) loops, respectively. Further C—H⋯N inter­actions form R22(10) loops and link the dimers into [110] chains.

CCDC reference: 978828

Related literature

For background to triazoles, see: Kiselyova et al. (2009[Kiselyova, A. S., Semenova, M. & Semenov, V. V. (2009). Bioorg. Med. Chem. Lett., 19, 1344-1348.]). For the synthesis, see: Zhang et al. (2012[Zhang, Q., Wang, X., Cheng, C., Zhu, R., Liu, N. & Hu, Y. (2012). Org. Biomol. Chem. 10, 2847-2854.]).

[Scheme 1]

Experimental

Crystal data

  • C13H14N4O2

  • Mr = 258.28

  • Triclinic, [P \overline 1]

  • a = 7.1565 (6) Å

  • b = 9.3521 (8) Å

  • c = 9.8747 (9) Å

  • α = 85.722 (4)°

  • β = 81.422 (4)°

  • γ = 86.941 (4)°

  • V = 651.09 (10) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 296 K

  • 0.42 × 0.30 × 0.28 mm
Data collection

  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.964, Tmax = 0.975

  • 8987 measured reflections

  • 2484 independent reflections

  • 1756 reflections with I > 2σ(I)

  • Rint = 0.029
Refinement

  • R[F2 > 2σ(F2)] = 0.046

  • wR(F2) = 0.137

  • S = 1.04

  • 2484 reflections

  • 173 parameters

  • H-atom parameters constrained

  • Δρmax = 0.12 e Å−3

  • Δρmin = −0.26 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C5—H5⋯N1i 0.93 2.60 3.375 (2) 141
C7—H7⋯N3ii 0.93 2.42 3.245 (2) 147
C9—H9⋯O2i 0.93 2.54 3.422 (2) 159
Symmetry codes: (i) -x+1, -y, -z+1; (ii) -x+2, -y+1, -z+1.

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: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and PLATON.

Supporting information

CCDC reference: 978828

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536813034673/hb7179sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813034673/hb7179Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813034673/hb7179Isup3.cml

checkCIF report


Comment top

There are many derivatives of 1-(pyridine-2yl)-1,2,3-triazole that have been used as an intermediates in organic synthesis, or as ligands in coordination chemistry which have shown biologically important properties (Kiselyova et al., 2009; Zhang et al., 2012). As part of our studies in this area, we report here the structure of the title compound (I), (Fig. 1).

In (I) the pyridine ring A (C4–C8/N1) and 1, 2,3-triazol ring B (C9/C10/N2/N3/N4) are almost planar with r.m.s. deviations of 0.0004 Å and 0.0014 Å, respectively. The dihedral angle between A/B is 7.61 (12)°. The ethyl acetate moiety attached with pyridine ring is also close to planar with r.m.s. deviation of 0.0088 Å and is oriented at a dihedral angle of 4.21 (15)° with ring A. The cyclopropyl moiety is of course planar and makes adihedral angle of 87.12 (12)° with the triazole ring. The molecules form dimers due to inversion and R22(6) an R22(10) loops are formed due to H-bondings of C—H····N and C—H····O types (Table 1, Fig. 2). The dimers are linked into [110] chains forming R22(10) ring motif due to C—H····N type of H-bonding.

Related literature top

For background to triazoles, see: Kiselyova et al. (2009). For the synthesis, see: Zhang et al. (2012).

Experimental top

To a suspension of ethyl tetrazolo [1,5-a]pyridine-6-carboxylate (0.25 g, 1 mmol), copper acetate (0.018 g, 0.1 mmol) in THF (2 ml) was stirred for 10 min, to give a deep red color suspension. Ethynylcyclopropane (0.072 g, 1.1 mmol) was added and the reaction mixture was stirred at room temperature for 40 min. The residue was purified by column chromatography to give 84% of product as white solid. Colourless prisms of (I) were grown by slow evaporation of an ethanol: ethyl acetate solution at room temperature (m.p. 394 K).

Refinement top

The H-atoms were positioned geometrically (C–H = 0.93–0.97 Å) and refined as riding with Uiso(H) = xUeq(C), where x = 1.5 for methyl and x = 1.2 for other H-atoms.

Structure description top

There are many derivatives of 1-(pyridine-2yl)-1,2,3-triazole that have been used as an intermediates in organic synthesis, or as ligands in coordination chemistry which have shown biologically important properties (Kiselyova et al., 2009; Zhang et al., 2012). As part of our studies in this area, we report here the structure of the title compound (I), (Fig. 1).

In (I) the pyridine ring A (C4–C8/N1) and 1, 2,3-triazol ring B (C9/C10/N2/N3/N4) are almost planar with r.m.s. deviations of 0.0004 Å and 0.0014 Å, respectively. The dihedral angle between A/B is 7.61 (12)°. The ethyl acetate moiety attached with pyridine ring is also close to planar with r.m.s. deviation of 0.0088 Å and is oriented at a dihedral angle of 4.21 (15)° with ring A. The cyclopropyl moiety is of course planar and makes adihedral angle of 87.12 (12)° with the triazole ring. The molecules form dimers due to inversion and R22(6) an R22(10) loops are formed due to H-bondings of C—H····N and C—H····O types (Table 1, Fig. 2). The dimers are linked into [110] chains forming R22(10) ring motif due to C—H····N type of H-bonding.

For background to triazoles, see: Kiselyova et al. (2009). For the synthesis, see: Zhang et al. (2012).

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: ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. View of the title compound with displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. Partial packing diagram of the title compound showing that molecules form dimers and various ring motifs as parts of chains.
Ethyl 6-(4-cyclopropyl-1H-1,2,3-triazol-1-yl)pyridine-3-carboxylate top
Crystal data top
C13H14N4O2Z = 2
Mr = 258.28F(000) = 272
Triclinic, P1Dx = 1.317 Mg m−3
a = 7.1565 (6) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.3521 (8) ÅCell parameters from 1756 reflections
c = 9.8747 (9) Åθ = 2.1–26.0°
α = 85.722 (4)°µ = 0.09 mm−1
β = 81.422 (4)°T = 296 K
γ = 86.941 (4)°Prism, colourless
V = 651.09 (10) Å30.42 × 0.30 × 0.28 mm
Data collection top
Bruker Kappa APEXII CCD
diffractometer		2484 independent reflections
Radiation source: fine-focus sealed tube1756 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.029
Detector resolution: 8.00 pixels mm-1θmax = 26.0°, θmin = 2.1°
ω scansh = −7→9
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		k = −11→11
Tmin = 0.964, Tmax = 0.975l = −12→12
8987 measured reflections
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)] = 0.046Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.137H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0667P)2 + 0.1169P]
where P = (Fo2 + 2Fc2)/3
2484 reflections(Δ/σ)max < 0.001
173 parametersΔρmax = 0.12 e Å−3
0 restraintsΔρmin = −0.26 e Å−3
Crystal data top
C13H14N4O2γ = 86.941 (4)°
Mr = 258.28V = 651.09 (10) Å3
Triclinic, P1Z = 2
a = 7.1565 (6) ÅMo Kα radiation
b = 9.3521 (8) ŵ = 0.09 mm−1
c = 9.8747 (9) ÅT = 296 K
α = 85.722 (4)°0.42 × 0.30 × 0.28 mm
β = 81.422 (4)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer		2484 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		1756 reflections with I > 2σ(I)
Tmin = 0.964, Tmax = 0.975Rint = 0.029
8987 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0460 restraints
wR(F2) = 0.137H-atom parameters constrained
S = 1.04Δρmax = 0.12 e Å−3
2484 reflectionsΔρmin = −0.26 e Å−3
173 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
xyzUiso*/Ueq
C10.2414 (3)0.6459 (2)0.0441 (2)0.0859 (7)
H1A0.23150.71470.11250.129*
H1B0.15200.6722−0.01790.129*
H1C0.36710.6441−0.00610.129*
C20.2005 (3)0.5009 (2)0.1119 (2)0.0751 (6)
H2A0.07390.50120.16330.090*
H2B0.20980.43020.04390.090*
C30.3330 (3)0.33974 (18)0.27255 (18)0.0522 (5)
C40.4902 (2)0.31531 (17)0.35605 (16)0.0458 (4)
C50.5060 (3)0.18591 (18)0.43204 (18)0.0521 (5)
H50.41540.11860.43030.062*
C60.7698 (2)0.25016 (17)0.50747 (16)0.0434 (4)
C70.7690 (3)0.38274 (18)0.43583 (19)0.0556 (5)
H70.86170.44770.43940.067*
C80.6251 (3)0.41465 (18)0.35887 (19)0.0545 (5)
H80.61880.50270.30900.065*
C90.9478 (2)0.08458 (17)0.66058 (16)0.0470 (4)
H90.88390.00020.66280.056*
C101.0960 (2)0.10746 (18)0.72627 (17)0.0480 (4)
C111.1936 (3)0.0111 (2)0.82036 (18)0.0589 (5)
H111.1577−0.08920.82800.071*
C121.2412 (3)0.0654 (3)0.9484 (2)0.0734 (6)
H12A1.21000.16550.96460.088*
H12B1.22920.00061.03040.088*
C131.3932 (3)0.0332 (3)0.8366 (2)0.0763 (6)
H13A1.4747−0.05140.84980.092*
H13B1.45540.11350.78400.092*
N31.0348 (2)0.30912 (16)0.61267 (17)0.0650 (5)
N41.1459 (2)0.24626 (17)0.69538 (17)0.0640 (5)
N10.6440 (2)0.15211 (14)0.50782 (15)0.0502 (4)
N20.9131 (2)0.21107 (14)0.59114 (13)0.0466 (4)
O10.34012 (19)0.46736 (13)0.20353 (14)0.0657 (4)
O20.2151 (2)0.25401 (15)0.26590 (15)0.0774 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0925 (17)0.0819 (16)0.0814 (16)0.0190 (13)−0.0276 (13)0.0204 (12)
C20.0823 (15)0.0681 (13)0.0825 (15)0.0107 (11)−0.0465 (12)0.0050 (11)
C30.0573 (11)0.0432 (9)0.0584 (11)−0.0001 (8)−0.0188 (9)0.0008 (8)
C40.0487 (10)0.0421 (9)0.0483 (10)−0.0026 (7)−0.0144 (8)0.0011 (7)
C50.0559 (11)0.0437 (9)0.0606 (11)−0.0134 (8)−0.0224 (9)0.0066 (8)
C60.0462 (9)0.0407 (9)0.0449 (9)−0.0068 (7)−0.0137 (7)0.0048 (7)
C70.0581 (11)0.0443 (9)0.0680 (12)−0.0169 (8)−0.0240 (9)0.0123 (8)
C80.0631 (11)0.0400 (9)0.0621 (11)−0.0085 (8)−0.0213 (9)0.0140 (8)
C90.0543 (10)0.0389 (9)0.0490 (10)−0.0059 (7)−0.0149 (8)0.0059 (7)
C100.0457 (10)0.0507 (10)0.0493 (10)−0.0040 (8)−0.0143 (8)0.0019 (7)
C110.0604 (12)0.0581 (11)0.0621 (12)−0.0009 (9)−0.0283 (9)0.0072 (9)
C120.0744 (14)0.0934 (16)0.0558 (12)0.0060 (12)−0.0259 (11)−0.0001 (11)
C130.0583 (13)0.1031 (17)0.0695 (14)0.0069 (11)−0.0248 (11)0.0038 (12)
N30.0659 (10)0.0523 (9)0.0836 (11)−0.0223 (8)−0.0369 (9)0.0176 (8)
N40.0615 (10)0.0589 (10)0.0776 (11)−0.0153 (8)−0.0344 (8)0.0137 (8)
N10.0543 (9)0.0429 (8)0.0570 (9)−0.0127 (6)−0.0219 (7)0.0092 (6)
N20.0496 (8)0.0417 (8)0.0513 (8)−0.0122 (6)−0.0183 (6)0.0073 (6)
O10.0711 (9)0.0536 (8)0.0781 (9)−0.0014 (6)−0.0386 (7)0.0135 (6)
O20.0769 (10)0.0619 (9)0.1036 (11)−0.0156 (8)−0.0500 (9)0.0114 (8)
Geometric parameters (Å, º) top
C1—C21.490 (3)C7—H70.9300
C1—H1A0.9600C8—H80.9300
C1—H1B0.9600C9—N21.353 (2)
C1—H1C0.9600C9—C101.357 (2)
C2—O11.453 (2)C9—H90.9300
C2—H2A0.9700C10—N41.365 (2)
C2—H2B0.9700C10—C111.471 (2)
C3—O21.206 (2)C11—C131.488 (3)
C3—O11.329 (2)C11—C121.489 (3)
C3—C41.490 (2)C11—H110.9800
C4—C81.380 (2)C12—C131.466 (3)
C4—C51.384 (2)C12—H12A0.9700
C5—N11.337 (2)C12—H12B0.9700
C5—H50.9300C13—H13A0.9700
C6—N11.318 (2)C13—H13B0.9700
C6—C71.381 (2)N3—N41.310 (2)
C6—N21.427 (2)N3—N21.347 (2)
C7—C81.376 (2)
C2—C1—H1A109.5N2—C9—H9127.5
C2—C1—H1B109.5C10—C9—H9127.5
H1A—C1—H1B109.5C9—C10—N4108.25 (15)
C2—C1—H1C109.5C9—C10—C11130.37 (16)
H1A—C1—H1C109.5N4—C10—C11121.34 (16)
H1B—C1—H1C109.5C10—C11—C13120.71 (18)
O1—C2—C1106.77 (18)C10—C11—C12119.78 (17)
O1—C2—H2A110.4C13—C11—C1258.99 (13)
C1—C2—H2A110.4C10—C11—H11115.3
O1—C2—H2B110.4C13—C11—H11115.3
C1—C2—H2B110.4C12—C11—H11115.3
H2A—C2—H2B108.6C13—C12—C1160.47 (14)
O2—C3—O1123.76 (17)C13—C12—H12A117.7
O2—C3—C4124.61 (16)C11—C12—H12A117.7
O1—C3—C4111.62 (15)C13—C12—H12B117.7
C8—C4—C5117.89 (16)C11—C12—H12B117.7
C8—C4—C3123.04 (15)H12A—C12—H12B114.8
C5—C4—C3119.04 (15)C12—C13—C1160.54 (14)
N1—C5—C4123.74 (16)C12—C13—H13A117.7
N1—C5—H5118.1C11—C13—H13A117.7
C4—C5—H5118.1C12—C13—H13B117.7
N1—C6—C7125.18 (15)C11—C13—H13B117.7
N1—C6—N2114.66 (14)H13A—C13—H13B114.8
C7—C6—N2120.14 (15)N4—N3—N2107.00 (14)
C8—C7—C6117.21 (16)N3—N4—C10109.09 (14)
C8—C7—H7121.4C6—N1—C5116.32 (14)
C6—C7—H7121.4N3—N2—C9110.61 (14)
C7—C8—C4119.65 (15)N3—N2—C6119.87 (13)
C7—C8—H8120.2C9—N2—C6129.50 (14)
C4—C8—H8120.2C3—O1—C2116.97 (15)
N2—C9—C10105.05 (14)
O2—C3—C4—C8178.53 (18)C10—C11—C13—C12108.5 (2)
O1—C3—C4—C8−0.3 (2)N2—N3—N4—C100.3 (2)
O2—C3—C4—C50.2 (3)C9—C10—N4—N3−0.4 (2)
O1—C3—C4—C5−178.58 (15)C11—C10—N4—N3−178.48 (16)
C8—C4—C5—N10.1 (3)C7—C6—N1—C50.1 (3)
C3—C4—C5—N1178.47 (16)N2—C6—N1—C5179.08 (14)
N1—C6—C7—C80.0 (3)C4—C5—N1—C6−0.1 (3)
N2—C6—C7—C8−178.94 (15)N4—N3—N2—C9−0.2 (2)
C6—C7—C8—C4−0.1 (3)N4—N3—N2—C6178.13 (15)
C5—C4—C8—C70.0 (3)C10—C9—N2—N3−0.04 (19)
C3—C4—C8—C7−178.31 (16)C10—C9—N2—C6−178.15 (16)
N2—C9—C10—N40.24 (19)N1—C6—N2—N3−171.57 (14)
N2—C9—C10—C11178.12 (17)C7—C6—N2—N37.5 (2)
C9—C10—C11—C13155.10 (19)N1—C6—N2—C96.4 (3)
N4—C10—C11—C13−27.3 (3)C7—C6—N2—C9−174.54 (16)
C9—C10—C11—C12−135.4 (2)O2—C3—O1—C2−2.2 (3)
N4—C10—C11—C1242.2 (3)C4—C3—O1—C2176.58 (15)
C10—C11—C12—C13−110.0 (2)C1—C2—O1—C3−178.22 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C5—H5···N1i0.932.603.375 (2)141
C7—H7···N3ii0.932.423.245 (2)147
C9—H9···O2i0.932.543.422 (2)159
Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+2, −y+1, −z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C5—H5···N1i0.932.603.375 (2)141
C7—H7···N3ii0.932.423.245 (2)147
C9—H9···O2i0.932.543.422 (2)159
Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+2, −y+1, −z+1.
 

Acknowledgements

MNA is highly thankful to the Higher Education Commission of Pakistan for financial support.

References

First citationBruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationBruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationFarrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationKiselyova, A. S., Semenova, M. & Semenov, V. V. (2009). Bioorg. Med. Chem. Lett., 19, 1344–1348.  Web of Science PubMed Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationSpek, A. L. (2009). Acta Cryst. D65, 148–155.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationZhang, Q., Wang, X., Cheng, C., Zhu, R., Liu, N. & Hu, Y. (2012). Org. Biomol. Chem. 10, 2847–2854.  Web of Science CrossRef CAS PubMed 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.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 70| Part 2| February 2014| Page o136
doi:10.1107/S1600536813034673
Follow Acta Cryst. E
Sign up for e-alerts
E-alerts
Follow Acta Cryst. on Twitter
Twitter
Follow us on facebook
Facebook
Sign up for RSS feeds
RSS