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Volume 69 
Part 7 
Page o1087  
July 2013  

Received 15 May 2013
Accepted 5 June 2013
Online 12 June 2013

Key indicators
Single-crystal X-ray study
T = 294 K
Mean [sigma](C-C) = 0.002 Å
R = 0.037
wR = 0.103
Data-to-parameter ratio = 14.8
Details
Open access

8[beta]-Ethoxyeremophil-3,7(11)-diene-8[alpha],12;6[alpha],15-diolide

aSchool of Pharmacy, Lanzhou University, Lanzhou 730000, People's Republic of China
Correspondence e-mail: feidq@lzu.edu.cn

The title compound, C17H20O5, an eremophilane sesquiternoid, was isolated from the roots of Ligularia lapathifolia. The molecule contains four fused rings of which the six-membered ring A adopts a half-chair conformation, the six-membered ring B adopts a chair conformation, the five-membered ring C is almost planar (r.m.s. deviation = 0.015 Å) and the five-membered ring D adopts an envelope conformation with the quaternary C atom as the flap. The methyl and the ethoxy groups adopt a syn conformation and the A/B ring junction is cis-fused. No directional intermolecular interactions could be identified in the crystal.

Related literature

For further information on the isolation of the title compound, see Fei et al. (2007[Fei, D.-Q., Li, S.-G., Liu, C.-M., Wu, G. & Gao, K. (2007). J. Nat. Prod. 70, 241-245.]). For pucking paramaters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]); Boeyens (1978[Boeyens, J. C. A. (1978). J. Cryst. Mol. Struct. 8, 317-320.])

[Scheme 1]

Experimental

Crystal data
  • C17H20O5

  • Mr = 304.33

  • Orthorhombic, P 21 21 21

  • a = 8.4925 (2) Å

  • b = 13.0302 (4) Å

  • c = 14.1381 (9) Å

  • V = 1564.50 (12) Å3

  • Z = 4

  • Cu K[alpha] radiation

  • [mu] = 0.78 mm-1

  • T = 294 K

  • 0.33 × 0.28 × 0.12 mm

Data collection
  • Agilent SuperNova (Dual, Cu at zero, Eos) diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2013[Agilent (2013). CrysAlis PRO. Agilent Technologies Ltd, Yarnton, England.]) Tmin = 0.743, Tmax = 1.000

  • 14336 measured reflections

  • 2994 independent reflections

  • 2871 reflections with I > 2[sigma](I)

  • Rint = 0.027

Refinement
  • R[F2 > 2[sigma](F2)] = 0.037

  • wR(F2) = 0.103

  • S = 1.03

  • 2994 reflections

  • 202 parameters

  • H-atom parameters constrained

  • [Delta][rho]max = 0.13 e Å-3

  • [Delta][rho]min = -0.18 e Å-3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.])

  • Flack parameter: -0.1 (2)

Data collection: CrysAlis PRO (Agilent, 2013[Agilent (2013). CrysAlis PRO. Agilent Technologies Ltd, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SUPERFLIP (Palatinus & Chapuis, 2007[Palatinus, L. & Chapuis, G. (2007). J. Appl. Cryst. 40, 786-790.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]); software used to prepare material for publication: OLEX2.


Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HB7083 ).


Acknowledgements

We are grateful to the National Natural Science Foundation of China (No. 21102065), the Natural Science Foundation of Gansu Province, China (No. 1208RJYA029) and the Fundational Research Funds for the Central Universities (Nos. lzujbky-2012-83 and lzujbky-2013-72) for financial support of this research.

References

Agilent (2013). CrysAlis PRO. Agilent Technologies Ltd, Yarnton, England.
Boeyens, J. C. A. (1978). J. Cryst. Mol. Struct. 8, 317-320.  [CrossRef]
Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.  [CrossRef] [ChemPort] [Web of Science]
Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.  [Web of Science] [CrossRef] [ChemPort] [IUCr Journals]
Fei, D.-Q., Li, S.-G., Liu, C.-M., Wu, G. & Gao, K. (2007). J. Nat. Prod. 70, 241-245.  [Web of Science] [CSD] [CrossRef] [PubMed] [ChemPort]
Flack, H. D. (1983). Acta Cryst. A39, 876-881.  [CrossRef] [IUCr Journals]
Palatinus, L. & Chapuis, G. (2007). J. Appl. Cryst. 40, 786-790.  [Web of Science] [CrossRef] [ChemPort] [IUCr Journals]
Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.  [CrossRef] [ChemPort] [IUCr Journals]


Acta Cryst (2013). E69, o1087  [ doi:10.1107/S1600536813015729 ]

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