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

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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 71| Part 3| March 2015| Page o162
doi:10.1107/S2056989015002510

Crystal structure of pseudoguainolide

CROSSMARK_Color_square_no_text.svg
Noureddine Beghidja,a* Samir Benayache,a Fadila Benayache,a David W. Knightb and Benson M. Kariukib*

aUnité de Recherche VARENBIOMOL, Constantine 1 University, Constantine 25000, Algeria, and bSchool of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, Wales
*Correspondence e-mail: nourbeghidja@yahoo.fr, kariukib@cf.ac.uk

Edited by E. R. T. Tiekink, University of Malaya, Malaysia (Received 8 January 2015; accepted 5 February 2015; online 11 February 2015)

The lactone ring in the title mol­ecule, C15H22O3 (systematic name: 3,4a,8-tri­methyl­dodeca­hydro­azuleno[6,5-b]furan-2,5-dione), assumes an envelope conformation with the methine C atom adjacent to the the methine C atom carrying the methyl substituent being the flap atom. The other five-membered ring adopts a twisted conformation with the twist being about the methine–methyl­ene C—C bond. The seven-membered ring is based on a twisted boat conformation. No specific inter­actions are noted in the the crystal packing.

CCDC reference: 1047797

1. Related literature

For background to inula graveolens, see: Chiappini & Fardella (1980[Chiappini, I. & Fardella, G. (1980). Fitoterapia, 51, 161-162.]); Rustaiyan et al. (1987[Rustaiyan, A., Jakupovic, J., Chau-Thi, T. V., Bohlmann, F. & Sadjadi, A. (1987). Phytochemistry, 26, 2603-2606.]). For related structures, see: Herz et al. (1982[Herz, W., Watanabe, K. & Blount, J. F. (1982). J. Org. Chem. 47, 3011-3012.]); Schmidt et al. (1996[Schmidt, T. J., Fronczek, F. R. & Liu, Y.-H. (1996). J. Mol. Struct. 385, 113-121.]); Wu et al. (2012[Wu, P., Su, M.-X., Wang, Y., Wang, G.-C., Ye, W.-C., Chung, H.-Y., Li, J., Jiang, R.-W. & Li, Y.-L. (2012). Phytochemistry, 76, 133-140.]); Billodeaux et al. (2014[Billodeaux, D. R., Menelaou, M. A., Fischer, N. H. & Fronczek, F. R. (2014). Private communication (deposition number CCDC 989352). CCDC, Cambridge, England.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C15H22O3

  • Mr = 250.33

  • Orthorhombic, P 21 21 21

  • a = 7.4320 (3) Å

  • b = 11.9278 (3) Å

  • c = 15.3152 (6) Å

  • V = 1357.65 (8) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 150 K

  • 0.20 × 0.20 × 0.04 mm

2.2. Data collection

  • Nonius KappaCCD diffractometer

  • Absorption correction: multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]) Tmin = 0.984, Tmax = 0.997

  • 9382 measured reflections

  • 3098 independent reflections

  • 2533 reflections with I > 2σ(I)

  • Rint = 0.041

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.047

  • wR(F2) = 0.107

  • S = 1.08

  • 3098 reflections

  • 166 parameters

  • H-atom parameters constrained

  • Δρmax = 0.15 e Å−3

  • Δρmin = −0.16 e Å−3

Data collection: COLLECT (Nonius, 2000[Nonius (2000). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]) and SCALEPACK; program(s) used to solve structure: SIR92 (Altomare et al., 1999[Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115-119.]); 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.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information

CCDC reference: 1047797

Crystal structure: contains datablocks I, New_Global_Publ_Block. DOI: 10.1107/S2056989015002510/tk5358sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2056989015002510/tk5358Isup2.hkl

Supporting information file. DOI: 10.1107/S2056989015002510/tk5358Isup3.cml

checkCIF report


Comment top

Inula graveolens have consistently been the subject of research interest (Chiappini & Fardella, 1980; Rustaiyan et al., 1987). Our interest is in the extracts from aerial parts of Algerian species such as stems, flowers and leaves. The asymmetric unit of the crystal structure consists of a single molecule (Fig. 1). In the molecule, the lactone ring assumes an envelope conformation. In the crystal structure, the planes of the lactone rings are approximately parallel. The molecules are arranged with the lactone rings stacked parallel to the a axis. Structures of some related compounds have been reported (Herz et al., 1982; Schmidt et al., 1996; Wu et al., 2012; Billodeaux et al., 2014).

Related literature top

For background to inula graveolens, see: Chiappini & Fardella (1980); Rustaiyan et al. (1987). For related structures, see: Herz et al. (1982); Schmidt et al. (1996); Wu et al. (2012); Billodeaux et al. (2014).

Experimental top

The air-dried aerial parts of inula graveolens (500 g) were extracted with acetone/Et2O (1:1) at room temperature. The solution was filtered off and concentrated under reduced pressure to give a pale-yellow gum (9 g). The gum was subjected to successive column chromatography (silica gel) and TLC (silica gel, PF254). Eleven fractions were obtained. Fraction 5 gave a material which crystallized as colourless crystals with a melting point of 152 oC.

Refinement top

Carbon-bound H-atoms were placed in calculated positions (C—H = 0.96–0.98 Å) and were included in the refinement in the riding model approximation, with Uiso(H) set to 1.2–1.5Uequiv(C).

Computing details top

Data collection: COLLECT (Nonius, 2000); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. A molecule showing atom labels and 50% probability displacement ellipsoids for non-H atoms.
3,4a,8-Trimethyldodecahydroazuleno[6,5-b]furan-2,5-dione top
Crystal data top
C15H22O3Dx = 1.225 Mg m−3
Mr = 250.33Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, P212121Cell parameters from 3098 reflections
a = 7.4320 (3) Åθ = 3.1–27.5°
b = 11.9278 (3) ŵ = 0.08 mm−1
c = 15.3152 (6) ÅT = 150 K
V = 1357.65 (8) Å3Plate, colourless
Z = 40.20 × 0.20 × 0.04 mm
F(000) = 544
Data collection top
Nonius KappaCCD
diffractometer		3098 independent reflections
Radiation source: fine-focus sealed tube2533 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.041
CCD slices, ω and ϕ scansθmax = 27.5°, θmin = 3.1°
Absorption correction: multi-scan
(DENZO/SCALEPACK; Otwinowski & Minor, 1997)		h = −9→9
Tmin = 0.984, Tmax = 0.997k = −15→15
9382 measured reflectionsl = −19→17
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)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.107H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.0453P)2 + 0.2031P]
where P = (Fo2 + 2Fc2)/3
3098 reflections(Δ/σ)max < 0.001
166 parametersΔρmax = 0.15 e Å−3
0 restraintsΔρmin = −0.16 e Å−3
Crystal data top
C15H22O3V = 1357.65 (8) Å3
Mr = 250.33Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 7.4320 (3) ŵ = 0.08 mm−1
b = 11.9278 (3) ÅT = 150 K
c = 15.3152 (6) Å0.20 × 0.20 × 0.04 mm
Data collection top
Nonius KappaCCD
diffractometer		3098 independent reflections
Absorption correction: multi-scan
(DENZO/SCALEPACK; Otwinowski & Minor, 1997)		2533 reflections with I > 2σ(I)
Tmin = 0.984, Tmax = 0.997Rint = 0.041
9382 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0470 restraints
wR(F2) = 0.107H-atom parameters constrained
S = 1.08Δρmax = 0.15 e Å−3
3098 reflectionsΔρmin = −0.16 e Å−3
166 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 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
C10.8136 (2)0.24699 (16)0.52812 (12)0.0383 (4)
C20.8423 (3)0.16380 (15)0.45546 (12)0.0407 (4)
H20.97220.15030.45220.049*
C30.7918 (2)0.22980 (13)0.37360 (11)0.0318 (4)
H30.66200.22200.36420.038*
C40.8307 (2)0.35109 (14)0.40005 (11)0.0338 (4)
H40.95520.37030.38520.041*
C50.8884 (2)0.19024 (14)0.29170 (12)0.0346 (4)
H5A0.83860.11830.27480.041*
H5B1.01420.17850.30600.041*
C60.8781 (2)0.26974 (15)0.21218 (12)0.0371 (4)
C70.7099 (3)0.34762 (15)0.20872 (12)0.0388 (4)
H70.60650.30390.22920.047*
C80.7176 (3)0.45618 (14)0.26350 (13)0.0429 (5)
H80.83260.49320.25130.052*
C90.7050 (3)0.43722 (14)0.36244 (12)0.0396 (4)
H9A0.72760.50810.39140.048*
H9B0.58270.41520.37630.048*
C100.8618 (3)0.20169 (18)0.12824 (14)0.0495 (5)
C110.7283 (4)0.25562 (19)0.06728 (14)0.0630 (6)
H11A0.62110.20990.06170.076*
H11B0.78050.26650.00980.076*
C120.6842 (3)0.36830 (18)0.10993 (14)0.0583 (6)
H12A0.56130.39050.09730.070*
H12B0.76510.42640.08930.070*
C130.7564 (3)0.05319 (14)0.47094 (13)0.0453 (5)
H13A0.62820.06230.47370.068*
H13B0.79920.02260.52510.068*
H13C0.78640.00320.42400.068*
C141.0567 (3)0.33493 (19)0.20250 (15)0.0519 (5)
H14A1.04880.38460.15330.078*
H14B1.15360.28300.19370.078*
H14C1.07860.37770.25450.078*
C150.5664 (3)0.53701 (18)0.23775 (17)0.0650 (7)
H15A0.56700.60040.27640.098*
H15B0.45260.49920.24190.098*
H15C0.58470.56200.17880.098*
O10.79726 (18)0.22938 (12)0.60507 (9)0.0478 (3)
O20.80792 (16)0.35200 (10)0.49559 (7)0.0390 (3)
O30.9465 (2)0.11791 (15)0.11224 (11)0.0721 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0265 (8)0.0451 (10)0.0433 (11)−0.0014 (8)−0.0003 (8)0.0008 (8)
C20.0416 (10)0.0404 (9)0.0400 (10)−0.0014 (8)0.0015 (8)0.0040 (8)
C30.0265 (8)0.0298 (8)0.0392 (9)−0.0018 (7)0.0004 (7)0.0008 (7)
C40.0296 (9)0.0335 (8)0.0384 (9)−0.0040 (7)0.0040 (7)−0.0020 (7)
C50.0314 (9)0.0331 (9)0.0393 (10)0.0025 (7)−0.0013 (8)−0.0011 (7)
C60.0344 (9)0.0381 (9)0.0387 (10)−0.0011 (8)0.0020 (8)0.0015 (8)
C70.0381 (9)0.0357 (8)0.0426 (10)0.0007 (8)−0.0058 (8)0.0050 (8)
C80.0453 (11)0.0301 (8)0.0534 (12)0.0008 (9)0.0005 (9)0.0064 (8)
C90.0373 (10)0.0303 (8)0.0512 (11)−0.0012 (8)0.0023 (9)−0.0031 (7)
C100.0526 (12)0.0532 (12)0.0426 (12)0.0015 (10)−0.0019 (9)−0.0027 (9)
C110.0807 (17)0.0660 (14)0.0424 (12)0.0121 (14)−0.0134 (12)−0.0037 (10)
C120.0731 (15)0.0544 (12)0.0472 (12)0.0092 (12)−0.0115 (12)0.0079 (9)
C130.0473 (11)0.0383 (10)0.0502 (12)0.0076 (9)0.0064 (9)0.0056 (8)
C140.0441 (11)0.0595 (12)0.0522 (13)−0.0096 (10)0.0101 (10)0.0073 (10)
C150.0772 (17)0.0419 (11)0.0761 (17)0.0178 (12)−0.0123 (14)0.0068 (11)
O10.0432 (8)0.0636 (8)0.0367 (8)−0.0003 (7)0.0028 (6)0.0023 (6)
O20.0380 (7)0.0401 (7)0.0388 (7)−0.0038 (6)0.0016 (6)−0.0055 (5)
O30.0840 (12)0.0763 (11)0.0560 (10)0.0307 (10)−0.0134 (9)−0.0248 (9)
Geometric parameters (Å, º) top
C1—O11.203 (2)C8—C151.532 (3)
C1—O21.349 (2)C8—C91.535 (3)
C1—C21.506 (3)C8—H80.9800
C2—C131.485 (2)C9—H9A0.9700
C2—C31.527 (2)C9—H9B0.9700
C2—H20.9800C10—O31.206 (2)
C3—C51.520 (2)C10—C111.507 (3)
C3—C41.530 (2)C11—C121.530 (3)
C3—H30.9800C11—H11A0.9700
C4—O21.473 (2)C11—H11B0.9700
C4—C91.503 (2)C12—H12A0.9700
C4—H40.9800C12—H12B0.9700
C5—C61.545 (3)C13—H13A0.9600
C5—H5A0.9700C13—H13B0.9600
C5—H5B0.9700C13—H13C0.9600
C6—C101.525 (3)C14—H14A0.9600
C6—C141.546 (3)C14—H14B0.9600
C6—C71.558 (3)C14—H14C0.9600
C7—C81.544 (3)C15—H15A0.9600
C7—C121.545 (3)C15—H15B0.9600
C7—H70.9800C15—H15C0.9600
O1—C1—O2121.39 (17)C9—C8—H8107.9
O1—C1—C2128.53 (18)C7—C8—H8107.9
O2—C1—C2110.08 (15)C4—C9—C8116.18 (15)
C13—C2—C1114.00 (15)C4—C9—H9A108.2
C13—C2—C3118.92 (16)C8—C9—H9A108.2
C1—C2—C3103.43 (14)C4—C9—H9B108.2
C13—C2—H2106.6C8—C9—H9B108.2
C1—C2—H2106.6H9A—C9—H9B107.4
C3—C2—H2106.6O3—C10—C11124.8 (2)
C5—C3—C2113.67 (14)O3—C10—C6124.83 (19)
C5—C3—C4115.01 (14)C11—C10—C6110.31 (17)
C2—C3—C4102.93 (13)C10—C11—C12104.58 (18)
C5—C3—H3108.3C10—C11—H11A110.8
C2—C3—H3108.3C12—C11—H11A110.8
C4—C3—H3108.3C10—C11—H11B110.8
O2—C4—C9107.71 (13)C12—C11—H11B110.8
O2—C4—C3104.38 (13)H11A—C11—H11B108.9
C9—C4—C3115.32 (15)C11—C12—C7104.55 (16)
O2—C4—H4109.7C11—C12—H12A110.8
C9—C4—H4109.7C7—C12—H12A110.8
C3—C4—H4109.7C11—C12—H12B110.8
C3—C5—C6115.87 (13)C7—C12—H12B110.8
C3—C5—H5A108.3H12A—C12—H12B108.9
C6—C5—H5A108.3C2—C13—H13A109.5
C3—C5—H5B108.3C2—C13—H13B109.5
C6—C5—H5B108.3H13A—C13—H13B109.5
H5A—C5—H5B107.4C2—C13—H13C109.5
C10—C6—C5109.98 (14)H13A—C13—H13C109.5
C10—C6—C14104.76 (16)H13B—C13—H13C109.5
C5—C6—C14109.96 (15)C6—C14—H14A109.5
C10—C6—C7103.01 (15)C6—C14—H14B109.5
C5—C6—C7115.63 (14)H14A—C14—H14B109.5
C14—C6—C7112.70 (14)C6—C14—H14C109.5
C8—C7—C12113.76 (15)H14A—C14—H14C109.5
C8—C7—C6116.85 (15)H14B—C14—H14C109.5
C12—C7—C6103.16 (15)C8—C15—H15A109.5
C8—C7—H7107.5C8—C15—H15B109.5
C12—C7—H7107.5H15A—C15—H15B109.5
C6—C7—H7107.5C8—C15—H15C109.5
C15—C8—C9107.59 (17)H15A—C15—H15C109.5
C15—C8—C7111.13 (17)H15B—C15—H15C109.5
C9—C8—C7114.24 (14)C1—O2—C4110.89 (13)
C15—C8—H8107.9

Experimental details

Crystal data
Chemical formulaC15H22O3
Mr250.33
Crystal system, space groupOrthorhombic, P212121
Temperature (K)150
a, b, c (Å)7.4320 (3), 11.9278 (3), 15.3152 (6)
V (Å3)1357.65 (8)
Z4
Radiation typeMo Kα
µ (mm−1)0.08
Crystal size (mm)0.20 × 0.20 × 0.04
Data collection
DiffractometerNonius KappaCCD
diffractometer
Absorption correctionMulti-scan
(DENZO/SCALEPACK; Otwinowski & Minor, 1997)
Tmin, Tmax0.984, 0.997
No. of measured, independent and
observed [I > 2σ(I)] reflections		9382, 3098, 2533
Rint0.041
(sin θ/λ)max (Å−1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.107, 1.08
No. of reflections3098
No. of parameters166
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.15, −0.16

Computer programs: COLLECT (Nonius, 2000), DENZO and SCALEPACK (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), WinGX (Farrugia, 2012).

 

Acknowledgements

The authors extend their appreciation to Constantine 1 University and Cardiff University for supporting this research.

References

First citationAltomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115–119.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationBillodeaux, D. R., Menelaou, M. A., Fischer, N. H. & Fronczek, F. R. (2014). Private communication (deposition number CCDC 989352). CCDC, Cambridge, England.  Google Scholar
 First citationChiappini, I. & Fardella, G. (1980). Fitoterapia, 51, 161–162.  CAS Google Scholar
 First citationFarrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationHerz, W., Watanabe, K. & Blount, J. F. (1982). J. Org. Chem. 47, 3011–3012.  CSD CrossRef CAS Web of Science Google Scholar
 First citationNonius (2000). COLLECT. Nonius BV, Delft, The Netherlands.  Google Scholar
 First citationOtwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307–326. New York: Academic Press.  Google Scholar
 First citationRustaiyan, A., Jakupovic, J., Chau-Thi, T. V., Bohlmann, F. & Sadjadi, A. (1987). Phytochemistry, 26, 2603–2606.  CrossRef CAS Web of Science Google Scholar
 First citationSchmidt, T. J., Fronczek, F. R. & Liu, Y.-H. (1996). J. Mol. Struct. 385, 113–121.  CSD CrossRef CAS Web of Science Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationWu, P., Su, M.-X., Wang, Y., Wang, G.-C., Ye, W.-C., Chung, H.-Y., Li, J., Jiang, R.-W. & Li, Y.-L. (2012). Phytochemistry, 76, 133–140.  Web of Science CSD 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 71| Part 3| March 2015| Page o162
doi:10.1107/S2056989015002510
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