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ISSN: 2056-9890

6-Hydr­­oxy-7-iso­propyl-1,1,4a-tri­methyl-2,3,4,4a,10,10a-hexa­hydro­phenanthren-9(1H)-one

aLaboratoire de Chimie Biomoléculaire, Substances Naturelles et Réactivité, Université Cadi Ayyad, Faculté des Sciences Semlalia, BP 2390 Marrakech, Morocco, and bLaboratoire de Chimie de Coordination, UPR-CNRS 8241, 205 route de Narbonne, 31077 Toulouse cédex, France
*Correspondence e-mail: daran@lcc-toulouse.fr

(Received 12 March 2008; accepted 21 March 2008; online 29 March 2008)

The title compound, C20H28O2, commonly named Sugiol, is a natural oxygenated diterpene that we have isolated for the first time from a hexane extract of the fruits of Juniperus Oxycedrus L. Its X-ray crystal structure determination confirms an abietane skeleton which was predicted by spectroscopic analysis, mainly by 1H and 13C NMR. The cyclo­hexane ring adopts a flattened chair conformation, while the cyclo­hexene ring adopts an envelope conformation. The mol­ecules are linked through O—H⋯O hydrogen bonds to form a zigzag chain extending parallel to the c axis.

Related literature

For related literature, see: Bai-Ping & Isao (1991[Bai-Ping, Y. & Isao, K. (1991). Phytochemistry, 30, 1951-1955.]); Bouhlal et al. (1988[Bouhlal, K., Meynadier, J. M., Peyron, J. L., Peyron, L., Marion, J. P., Bonetti, G. & Meynadier, J. (1988). Parfums Cosmét. Arômes, 83, 73-82.]); Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]); Iwamato et al. (2003[Iwamato, M., Minami, T., Tokuda, H., Ohtsu, H. & Tanaka, R. (2003). Planta Med. 69, 69-72.]); Politi et al. (2003[Politi, M., Braca, A., Tommasi, N. D., Morelli, I., Manunuta, A., Battinell, L. & Mazzanti, G. (2003). Planta Med. 69, 468-470.]); Ulubelen et al. (1997[Ulubelen, A., Topcu, G. & Johansson, C. B. (1997). J. Nat. Prod. 60, 1275-1280.]).

[Scheme 1]

Experimental

Crystal data
  • C20H28O2

  • Mr = 300.42

  • Orthorhombic, P 21 21 21

  • a = 9.6060 (4) Å

  • b = 12.6617 (6) Å

  • c = 14.0920 (7) Å

  • V = 1713.99 (14) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.07 mm−1

  • T = 180 (2) K

  • 0.31 × 0.16 × 0.07 mm

Data collection
  • Oxford Diffraction Xcalibur diffractometer

  • Absorption correction: none

  • 13398 measured reflections

  • 2003 independent reflections

  • 1212 reflections with I > 2σ(I)

  • Rint = 0.068

Refinement
  • R[F2 > 2σ(F2)] = 0.046

  • wR(F2) = 0.154

  • S = 1.05

  • 2003 reflections

  • 205 parameters

  • H-atom parameters constrained

  • Δρmax = 0.36 e Å−3

  • Δρmin = −0.38 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O6—H6⋯O9i 0.82 1.84 2.642 (4) 165
Symmetry code: (i) [-x+{\script{1\over 2}}, -y+1, z+{\script{1\over 2}}].

Data collection: CrysAlis CCD (Oxford Diffraction, 2007[Oxford Diffraction (2007). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2007[Oxford Diffraction (2007). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]); data reduction: CrysAlis RED; program(s) used to solve structure: SIR97 (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: ORTEPIII (Burnett & Johnson, 1996[Burnett, M. N. & Johnson, C. K. (1996). ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.]), ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

Juniperus oxycedrus L. has been used in traditional folk medicine for the treatment of chronic eczema and other several skin diseases (Bouhlal et al., 1988). Diterpenes are among the identified chemical constituents of this plant. They are of great interest with respect to their biological activity including antitumor, antituberculous and antimalarial effects (Iwamato et al., 2003; Politi et al., 2003; Ulubelen et al., 1997).

The structure of the title compound is built up by three fused six-membered rings A, B and C (Fig. 1). B displays an envelope conformation with puckering parameters, Q=0.510 (4) Å, θ= 124.6 (4)° and ϕ= 227.1 (6)° (Cremer & Pople, 1975) whereas C has a flattened chair conformation with Q= 0.546 (4) Å, θ = 5.0 (4) and ϕ = 234 (5)°. A is an aromatic ring and it is perfectly planar. The molecules are linked through O—H···O hydrogen bonds involving the hydroxyl group as a donor and the ketone oxygen as an acceptor yielding a zig zag chain developing parallel to the c axis (Fig. 2, Table 1).

Related literature top

For related literature, see: Bai-Ping & Isao (1991); Bouhlal et al. (1988); Cremer & Pople (1975); Iwamato et al. (2003); Politi et al. (2003); Ulubelen et al. (1997).

Experimental top

In order to isolate similar compounds, we have studied the chemical composition of the fruits of Juniperus oxycedrus L. Thus, 203 g of pulverized cones was extracted with hexane. The solvent was evaporated under reduced pressure to give 14.3 g of the crude hexanic extract which was purified on silica gel column chromatography using hexane–AcOEt (97:3) as eluent, to give crystals of Sugiol (I). All 1H and 13C NMR spectroscopic data of the isolated product were in full accord with the litterature (Bai-Ping & Isao, 1991).

Refinement top

All H atoms attached to C and O atoms were fixed geometrically and treated as riding with C—H = 0.93 Å (aromatic), 0.98 Å (methine), 0.97 Å (methylene), 0.96 Å (methyl) and O—H = 0.82 Å with Uiso(H) = 1.2Ueq or Uiso(H) = 1.5Ueq(methyl, OH).

In the absence of significant anomalous scattering, the absolute configuration could not be reliably determined and then the Friedel pairs were merged and any references to the Flack parameter were removed.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2007); cell refinement: CrysAlis RED (Oxford Diffraction, 2007); data reduction: CrysAlis RED (Oxford Diffraction, 2007); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. Molecular view of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are represented as small spheres of arbitrary radii.
[Figure 2] Fig. 2. Partial packing view of the compound, showing the formation of the zig zag chain parallel to the c axis and built from O—H···O hydrogen bonds. H atoms not involved in hydrogen bonding have been omitted for clarity. [symmetry codes: (i) -x + 1/2,-y + 1, z + 1/2].
6-Hydroxy-7-isopropyl-1,1,4a-trimethyl-2,3,4,4a,10,10a-hexahydrophenanthren- 9(1H)-one top
Crystal data top
C20H28O2F(000) = 656
Mr = 300.42Dx = 1.164 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 3571 reflections
a = 9.6060 (4) Åθ = 2.7–32.1°
b = 12.6617 (6) ŵ = 0.07 mm1
c = 14.0920 (7) ÅT = 180 K
V = 1713.99 (14) Å3Flattened box, colorless
Z = 40.31 × 0.16 × 0.07 mm
Data collection top
Oxford Diffraction Xcalibur
diffractometer
1212 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.068
Graphite monochromatorθmax = 26.4°, θmin = 2.7°
Detector resolution: 8.2632 pixels mm-1h = 1212
ω and ϕ scansk = 1515
13398 measured reflectionsl = 1417
2003 independent 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) = 0.154H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0842P)2]
where P = (Fo2 + 2Fc2)/3
2003 reflections(Δ/σ)max < 0.001
205 parametersΔρmax = 0.36 e Å3
0 restraintsΔρmin = 0.38 e Å3
Crystal data top
C20H28O2V = 1713.99 (14) Å3
Mr = 300.42Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 9.6060 (4) ŵ = 0.07 mm1
b = 12.6617 (6) ÅT = 180 K
c = 14.0920 (7) Å0.31 × 0.16 × 0.07 mm
Data collection top
Oxford Diffraction Xcalibur
diffractometer
1212 reflections with I > 2σ(I)
13398 measured reflectionsRint = 0.068
2003 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0460 restraints
wR(F2) = 0.154H-atom parameters constrained
S = 1.05Δρmax = 0.36 e Å3
2003 reflectionsΔρmin = 0.38 e Å3
205 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 > 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
C10.0789 (4)0.8588 (3)0.0839 (3)0.0291 (10)
C20.1754 (4)0.9176 (3)0.1515 (3)0.0339 (11)
H2A0.26740.92110.12340.041*
H2B0.14180.98940.15880.041*
C30.1869 (5)0.8673 (3)0.2486 (3)0.0366 (11)
H3A0.09660.86810.27940.044*
H3B0.25110.90770.28740.044*
C40.2389 (4)0.7525 (3)0.2400 (3)0.0296 (10)
H4A0.24300.72150.30290.036*
H4B0.33270.75310.21450.036*
C4A0.1464 (4)0.6828 (3)0.1762 (3)0.0217 (9)
C4B0.2182 (4)0.5776 (3)0.1555 (3)0.0202 (9)
C50.3090 (4)0.5314 (3)0.2203 (3)0.0252 (9)
H50.32860.56610.27680.030*
C60.3699 (4)0.4356 (3)0.2023 (3)0.0255 (9)
C70.3444 (4)0.3792 (3)0.1186 (3)0.0296 (10)
C80.2533 (4)0.4252 (3)0.0564 (3)0.0244 (10)
H80.23350.38980.00020.029*
C8A0.1892 (4)0.5211 (3)0.0724 (3)0.0219 (9)
C90.0961 (4)0.5626 (3)0.0010 (3)0.0220 (9)
C100.0395 (4)0.6713 (3)0.0137 (3)0.0307 (10)
H10A0.05450.66630.03840.037*
H10B0.03440.70540.04790.037*
C10A0.1257 (4)0.7408 (3)0.0804 (3)0.0227 (9)
H10C0.21860.74260.05180.027*
C110.0945 (5)0.9073 (3)0.0143 (3)0.0455 (13)
H11A0.08470.98260.00990.068*
H11B0.02390.87950.05560.068*
H11C0.18470.89050.03930.068*
C120.0741 (4)0.8754 (3)0.1138 (3)0.0397 (12)
H12A0.10130.94680.10060.060*
H12B0.08360.86180.18050.060*
H12C0.13280.82780.07900.060*
C130.0112 (4)0.6551 (3)0.2292 (3)0.0333 (11)
H13A0.04940.61620.18790.050*
H13B0.03430.71900.24900.050*
H13C0.03280.61300.28390.050*
C140.4133 (5)0.2730 (3)0.1025 (3)0.0322 (11)
H140.51000.27920.12400.039*
C150.4171 (6)0.2384 (4)0.0019 (4)0.0672 (18)
H15A0.32390.22610.02010.101*
H15B0.47010.17430.00320.101*
H15C0.45980.29230.03620.101*
C160.3443 (6)0.1868 (4)0.1627 (4)0.0614 (16)
H16A0.25160.17440.13990.092*
H16B0.34060.20930.22770.092*
H16C0.39760.12290.15820.092*
O60.4598 (3)0.3917 (2)0.2654 (2)0.0353 (8)
H60.46410.42870.31310.053*
O90.0639 (3)0.5113 (2)0.06942 (18)0.0304 (7)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.033 (2)0.018 (2)0.036 (2)0.0086 (18)0.001 (2)0.0033 (19)
C20.033 (2)0.021 (2)0.048 (3)0.0042 (19)0.000 (2)0.002 (2)
C30.032 (2)0.029 (2)0.048 (3)0.001 (2)0.008 (2)0.014 (2)
C40.032 (2)0.027 (2)0.029 (2)0.0046 (19)0.0046 (19)0.0085 (19)
C4A0.022 (2)0.021 (2)0.022 (2)0.0028 (16)0.0010 (18)0.0000 (17)
C4B0.0183 (18)0.0196 (19)0.023 (2)0.0009 (16)0.0041 (18)0.0026 (17)
C50.028 (2)0.025 (2)0.023 (2)0.0008 (18)0.000 (2)0.0038 (18)
C60.029 (2)0.028 (2)0.019 (2)0.0069 (19)0.0023 (18)0.0033 (19)
C70.032 (3)0.025 (2)0.032 (2)0.0043 (19)0.007 (2)0.002 (2)
C80.028 (2)0.023 (2)0.022 (2)0.0025 (19)0.0002 (18)0.0010 (18)
C8A0.026 (2)0.0196 (19)0.020 (2)0.0039 (17)0.0026 (19)0.0021 (18)
C90.024 (2)0.021 (2)0.020 (2)0.0005 (17)0.0018 (18)0.0018 (18)
C100.033 (2)0.032 (2)0.027 (2)0.0024 (19)0.006 (2)0.0011 (19)
C10A0.021 (2)0.024 (2)0.023 (2)0.0048 (16)0.0008 (18)0.0035 (18)
C110.059 (3)0.029 (3)0.049 (3)0.008 (2)0.001 (3)0.011 (2)
C120.035 (3)0.035 (3)0.048 (3)0.013 (2)0.009 (2)0.010 (2)
C130.030 (2)0.033 (2)0.037 (3)0.0033 (19)0.003 (2)0.003 (2)
C140.036 (3)0.025 (2)0.035 (2)0.010 (2)0.002 (2)0.0025 (18)
C150.093 (5)0.065 (4)0.044 (3)0.045 (4)0.001 (3)0.011 (3)
C160.067 (4)0.036 (3)0.080 (4)0.006 (3)0.017 (3)0.006 (3)
O60.0436 (18)0.0353 (17)0.0271 (17)0.0196 (15)0.0073 (15)0.0031 (14)
O90.0393 (17)0.0288 (15)0.0231 (15)0.0002 (14)0.0061 (14)0.0076 (13)
Geometric parameters (Å, º) top
C1—C111.521 (6)C8A—C91.445 (5)
C1—C21.524 (6)C9—O91.226 (4)
C1—C121.543 (6)C9—C101.491 (5)
C1—C10A1.561 (5)C10—C10A1.530 (5)
C2—C31.514 (6)C10—H10A0.9700
C2—H2A0.9700C10—H10B0.9700
C2—H2B0.9700C10A—H10C0.9800
C3—C41.542 (5)C11—H11A0.9600
C3—H3A0.9700C11—H11B0.9600
C3—H3B0.9700C11—H11C0.9600
C4—C4A1.542 (5)C12—H12A0.9600
C4—H4A0.9700C12—H12B0.9600
C4—H4B0.9700C12—H12C0.9600
C4A—C4B1.528 (5)C13—H13A0.9600
C4A—C131.539 (5)C13—H13B0.9600
C4A—C10A1.550 (5)C13—H13C0.9600
C4B—C51.391 (5)C14—C151.485 (6)
C4B—C8A1.401 (5)C14—C161.532 (6)
C5—C61.370 (5)C14—H140.9800
C5—H50.9300C15—H15A0.9600
C6—O61.359 (4)C15—H15B0.9600
C6—C71.401 (5)C15—H15C0.9600
C7—C81.369 (5)C16—H16A0.9600
C7—C141.517 (5)C16—H16B0.9600
C8—C8A1.380 (5)C16—H16C0.9600
C8—H80.9300O6—H60.8200
C11—C1—C2108.1 (4)C8A—C9—C10118.6 (3)
C11—C1—C12106.7 (4)C9—C10—C10A114.0 (3)
C2—C1—C12110.0 (3)C9—C10—H10A108.7
C11—C1—C10A109.3 (3)C10A—C10—H10A108.7
C2—C1—C10A108.2 (3)C9—C10—H10B108.7
C12—C1—C10A114.4 (3)C10A—C10—H10B108.7
C3—C2—C1113.9 (3)H10A—C10—H10B107.6
C3—C2—H2A108.8C10—C10A—C4A109.4 (3)
C1—C2—H2A108.8C10—C10A—C1114.4 (3)
C3—C2—H2B108.8C4A—C10A—C1117.6 (3)
C1—C2—H2B108.8C10—C10A—H10C104.6
H2A—C2—H2B107.7C4A—C10A—H10C104.6
C2—C3—C4110.4 (3)C1—C10A—H10C104.6
C2—C3—H3A109.6C1—C11—H11A109.5
C4—C3—H3A109.6C1—C11—H11B109.5
C2—C3—H3B109.6H11A—C11—H11B109.5
C4—C3—H3B109.6C1—C11—H11C109.5
H3A—C3—H3B108.1H11A—C11—H11C109.5
C3—C4—C4A113.5 (3)H11B—C11—H11C109.5
C3—C4—H4A108.9C1—C12—H12A109.5
C4A—C4—H4A108.9C1—C12—H12B109.5
C3—C4—H4B108.9H12A—C12—H12B109.5
C4A—C4—H4B108.9C1—C12—H12C109.5
H4A—C4—H4B107.7H12A—C12—H12C109.5
C4B—C4A—C13106.0 (3)H12B—C12—H12C109.5
C4B—C4A—C4110.5 (3)C4A—C13—H13A109.5
C13—C4A—C4109.5 (3)C4A—C13—H13B109.5
C4B—C4A—C10A107.8 (3)H13A—C13—H13B109.5
C13—C4A—C10A115.0 (3)C4A—C13—H13C109.5
C4—C4A—C10A108.1 (3)H13A—C13—H13C109.5
C5—C4B—C8A117.3 (3)H13B—C13—H13C109.5
C5—C4B—C4A121.6 (3)C15—C14—C7114.6 (4)
C8A—C4B—C4A121.0 (3)C15—C14—C16109.2 (4)
C6—C5—C4B121.3 (4)C7—C14—C16111.0 (4)
C6—C5—H5119.4C15—C14—H14107.2
C4B—C5—H5119.4C7—C14—H14107.2
O6—C6—C5120.9 (4)C16—C14—H14107.2
O6—C6—C7117.0 (3)C14—C15—H15A109.5
C5—C6—C7122.2 (4)C14—C15—H15B109.5
C8—C7—C6115.8 (3)H15A—C15—H15B109.5
C8—C7—C14124.1 (4)C14—C15—H15C109.5
C6—C7—C14120.1 (4)H15A—C15—H15C109.5
C7—C8—C8A123.7 (4)H15B—C15—H15C109.5
C7—C8—H8118.2C14—C16—H16A109.5
C8A—C8—H8118.2C14—C16—H16B109.5
C8—C8A—C4B119.8 (4)H16A—C16—H16B109.5
C8—C8A—C9118.9 (3)C14—C16—H16C109.5
C4B—C8A—C9121.3 (3)H16A—C16—H16C109.5
O9—C9—C8A121.7 (3)H16B—C16—H16C109.5
O9—C9—C10119.6 (4)C6—O6—H6109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O6—H6···O9i0.821.842.642 (4)165
Symmetry code: (i) x+1/2, y+1, z+1/2.

Experimental details

Crystal data
Chemical formulaC20H28O2
Mr300.42
Crystal system, space groupOrthorhombic, P212121
Temperature (K)180
a, b, c (Å)9.6060 (4), 12.6617 (6), 14.0920 (7)
V3)1713.99 (14)
Z4
Radiation typeMo Kα
µ (mm1)0.07
Crystal size (mm)0.31 × 0.16 × 0.07
Data collection
DiffractometerOxford Diffraction Xcalibur
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
13398, 2003, 1212
Rint0.068
(sin θ/λ)max1)0.625
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.046, 0.154, 1.05
No. of reflections2003
No. of parameters205
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.36, 0.38

Computer programs: CrysAlis CCD (Oxford Diffraction, 2007), CrysAlis RED (Oxford Diffraction, 2007), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O6—H6···O9i0.821.842.642 (4)164.8
Symmetry code: (i) x+1/2, y+1, z+1/2.
 

References

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