3β-Acet­oxy-8β,10β-dihy­droxy-6β-meth­oxy­eremophil-7(11)-en-8,12-olide

Wu, H.-B.; Li, H.; Lan, X.-C.; Wang, W.-S.

doi:10.1107/S1600536810029831

Volume 66
Part 8
Page o2161
August 2010

Received 5 July 2010
Accepted 27 July 2010
Online 31 July 2010

Key indicators
Single-crystal X-ray study
T = 293 K
Mean (C-C) = 0.006 Å
R = 0.049
wR = 0.139
Data-to-parameter ratio = 8.3
Details

3-Acetoxy-8,10-dihydroxy-6-methoxyeremophil-7(11)-en-8,12-olide

Hai-Bo Wu,^a Hua Li,^a Xiao-Cong Lan ^a and Wen-Shu Wang ^a ^*

^aCollege of Life and Environment Science, Minzu University of China, Beijing 100081, People's Republic of China
Correspondence e-mail: wangwshu@gmail.com

The title compound, C₁₈H₂₆O₇, is an eremophilenolide which has been isolated from the plant Ligularia duciformis for the first time. The present study confirms the atomic connectivity assigned on the basis of ¹H and ¹³C NMR spectroscopy. The molecule contains three fused rings, two six-membered rings in chair confomations and a five-membered ring in a flattened envelope conformation. Two hydroxy groups are involved in formation of intra- and intermolecular O-HO hydrogen bonds. The latter ones link molecules into chains propagating in [010].

Related literature

For related compounds extracted from Ligularia duciformis and Cacalia roborowski, see Wang et al. (2008) and Zhang et al. (1998), respectively.

Experimental

Crystal data

C₁₈H₂₆O₇
M_r = 354.39
Orthorhombic, P 2₁ 2₁ 2₁
a = 7.3036 (15) Å
b = 9.789 (2) Å
c = 25.553 (5) Å
V = 1826.9 (6) Å³
Z = 4
Mo K radiation
= 0.10 mm^-1
T = 293 K
0.50 × 0.50 × 0.20 mm

Data collection

Rigaku R-AXIS RAPID IP diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995) T_min = 0.952, T_max = 0.980
12058 measured reflections
1885 independent reflections
1203 reflections with I > 2(I)
R_int = 0.061

Refinement

R[F² > 2(F²)] = 0.049
wR(F²) = 0.139
S = 0.89
1885 reflections
227 parameters
H-atom parameters constrained
_max = 0.29 e Å^-3
_min = -0.36 e Å^-3

Table 1
Hydrogen-bond geometry (Å, °)

D-HA	D-H	HA	DA	D-HA
O2-H2AO3	0.82	2.19	2.879 (4)	142
O3-H3AO2ⁱ	0.82	2.06	2.755 (4)	143
Symmetry code: (i) $[-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Data collection: RAPID-AUTO (Rigaku, 2000); cell refinement: RAPID-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick,2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: CV2743 ).

Acknowledgements

The project was supported by the 985 Project (MUC985) Minzu University of China, and the Major Project for Young Teachers in Minzu University of China CUN10A, together with the `Programme of Introducing Talents of Discipline to Universities' (B08044), and the `Project for Scientific and Technical Achievements in Industrialization', Beijing Education Commission.

References

Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.
Rigaku (2000). RAPID-AUTO. Rigaku Corporation, Tokyo, Japan.
Rigaku/MSC (2000). Crystal Structure. Rigaku/MSC, Tokyo, Japan.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.
Wang, W. S., Dai, X., Hong, L. Y., Lu, P., Feng, J. C. & Jiao, Y. G. (2008). Helv. Chim. Acta, 91, 1118-1123.
Zhang, S. M., Zhao, G. L., Li, R. & Lin, G. Q. (1998). Phytochemistry, 48, 519-524.

organic compounds