1β,10α:4β,5α-Diep­oxy-7αH-germacran-6β-ol monohydrate

He, M.-H.; Yang, Q.; Sun, J.

doi:10.1107/S1600536810047732

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 66| Part 12| December 2010| Page o3263

https://doi.org/10.1107/S1600536810047732

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1β,10α:4β,5α-Diepoxy-7αH-germacran-6β-ol monohydrate

Meng-Hui He,^a Quan Yang ^b ^* and Jie Sun ^c

^aSchool of Life Science, Foshan University, Foshan 528231, People's Republic of China, ^bSchool of Chinese Medicine, Guangdong Pharmaceutical University, Guangzhou 510006, People's Republic of China, and ^cShanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 20032, People's Republic of China
^*Correspondence e-mail: yangquan7208@vip.163.com

(Received 28 September 2010; accepted 17 November 2010; online 20 November 2010)

In the title compound, C₁₅H₂₆O₃·H₂O, a sesquiterpenoid molecule with a germacrene backbone that contains two epoxide groups and one hydroxyl group. Intermolecular O—H⋯O hydrogen bonds between the epoxy groups and solvent water molecules give rise to an infinite three-dimensional supramolecular structure.

Related literature

For the biosystematic and ecological evaluation of the title compound, see: Al Yousuf et al. (1999 ). For the isolation, see Li et al. (2009 ). For the determination of its absolute structure, see: Aguilar-Guadarrama & Rios (2004 ), Moodley et al. (2004 ). For related structures, see Takahashi et al. (1983 ), Barrero et al. (1999 ).

Experimental

Crystal data

C₁₅H₂₆O₃·H₂O
M_r = 272.37
Orthorhombic, P 2₁ 2₁ 2₁
a = 8.087 (2) Å
b = 11.380 (3) Å
c = 16.943 (5) Å
V = 1559.2 (8) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 293 K
0.31 × 0.13 × 0.07 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2000 ) T_min = 0.757, T_max = 1.000
8291 measured reflections
1759 independent reflections
1281 reflections with I > 2σ(I)
R_int = 0.080

Refinement

R[F² > 2σ(F²)] = 0.062
wR(F²) = 0.148
S = 1.06
1759 reflections
186 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.16 e Å⁻³
Δρ_min = −0.15 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H3⋯O4ⁱ	0.82	2.03	2.819 (4)	160
O4—H4⋯O2ⁱⁱ	0.94 (6)	1.92 (6)	2.836 (5)	164 (5)
O4—H4C⋯O3	0.93 (4)	2.10 (5)	3.013 (4)	166 (4)
Symmetry codes: (i) $[-x+{\script{1\over 2}}, -y+2, z-{\script{1\over 2}}]$ ; (ii) $[-x, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Data collection: SMART (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; 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: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810047732/jj2065sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810047732/jj2065Isup2.hkl

checkCIF report

Comment top

Terpenoids are large naturally-occuring organic molecules derived from five-carbon isoprene units assembled and modified in numerous ways. A sesquiterpenoid is a 15-carbon modified multicyclic terpenoid hydrocarbon molecule that differs from one another in its functional groups. The title compound, C₁₅H₂₆O₃, H₂O, is a sesquiterpenoid molecule with a germacrene backbone that contains two epoxide groups at the 1–10 and 4–5 ring positions and one alcohol group at the C6 position, respectively (Fig. 1). Crystal packing hss been stabilized as a result of a single water molecule that has crystallized in the unit cell giving rise to O—H···O intermolecular hydrogen bonds between the epoxy groups and the adjacent water molecules (Table 1). This forms an infinite 3-D supramolecular structure (Fig. 2).

Related literature top

For the biosystematic and ecological evaluation of the title compound, see: Al Yousuf et al. (1999). For the synthesis, see Li et al. (2009). For the determination of its absolute structure, see: Aguilar-Guadarrama & Rios (2004), Moodley et al. (2004). For related structures, see Takahashi et al. (1983), Barrero et al. (1999).

Experimental top

The title compound was synthesized by the method of Li et al. (2009). It was purified by repeated column chromatography over silica gel, ODS, and sephadex LH-20. It was then dissolved in a mixed solution of chloroform and methanol (ca 5:1). Colorless needle-like crystals were formed by slow evaporation of the solution in air.

Structure description top

Computing details top

Data collection: SMART (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: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound, showing 30% displacement ellipsoids.
	Fig. 2. Packing diagram of the title compound viewed down the a axis. Dashed lines indicate O—H—O hydrogen bonds.

1β,10α:4β,5α-Diepoxy-7αH-germacran-6β-ol monohydrate top

Crystal data top

C₁₅H₂₆O₃·H₂O	F(000) = 600
M_r = 272.37	D_x = 1.160 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 1361 reflections
a = 8.087 (2) Å	θ = 4.8–39.9°
b = 11.380 (3) Å	µ = 0.08 mm⁻¹
c = 16.943 (5) Å	T = 293 K
V = 1559.2 (8) Å³	Prismatic, colorless
Z = 4	0.31 × 0.13 × 0.07 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	1759 independent reflections
Radiation source: fine-focus sealed tube	1281 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.080
φ and ω scans	θ_max = 26.0°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 2000)	h = −9→9
T_min = 0.757, T_max = 1.000	k = −14→11
8291 measured reflections	l = −20→20

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.062	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.148	w = 1/[σ²(F_o²) + (0.0727P)²] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max = 0.005
1759 reflections	Δρ_max = 0.16 e Å⁻³
186 parameters	Δρ_min = −0.15 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.010 (3)

Crystal data top

C₁₅H₂₆O₃·H₂O	V = 1559.2 (8) Å³
M_r = 272.37	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 8.087 (2) Å	µ = 0.08 mm⁻¹
b = 11.380 (3) Å	T = 293 K
c = 16.943 (5) Å	0.31 × 0.13 × 0.07 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	1759 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2000)	1281 reflections with I > 2σ(I)
T_min = 0.757, T_max = 1.000	R_int = 0.080
8291 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.062	0 restraints
wR(F²) = 0.148	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	Δρ_max = 0.16 e Å⁻³
1759 reflections	Δρ_min = −0.15 e Å⁻³
186 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

	x	y	z	U_iso*/U_eq
O1	0.3976 (4)	1.2287 (2)	0.77838 (15)	0.0499 (8)
O2	0.3551 (4)	1.2022 (2)	0.59240 (17)	0.0540 (9)
H3	0.4081	1.2005	0.5512	0.081*
O3	0.1549 (4)	0.7702 (2)	0.79520 (15)	0.0519 (8)
O4	−0.0212 (5)	0.7428 (3)	0.9509 (2)	0.0686 (11)
C1	0.2708 (6)	0.8691 (3)	0.7992 (2)	0.0402 (10)
H1	0.3781	0.8546	0.7742	0.048*
C2	0.2798 (6)	0.9355 (3)	0.8767 (2)	0.0505 (12)
H2A	0.3750	0.9079	0.9063	0.061*
H2B	0.1818	0.9180	0.9075	0.061*
C3	0.2933 (6)	1.0692 (3)	0.8662 (2)	0.0527 (12)
H3A	0.1844	1.1006	0.8545	0.063*
H3B	0.3303	1.1038	0.9154	0.063*
C4	0.4113 (6)	1.1048 (3)	0.8008 (2)	0.0420 (10)
C5	0.3410 (5)	1.1380 (3)	0.7247 (2)	0.0396 (10)
H5	0.2204	1.1304	0.7220	0.048*
C6	0.4256 (5)	1.1207 (3)	0.64782 (19)	0.0402 (10)
H6	0.5433	1.1386	0.6542	0.048*
C7	0.4075 (5)	0.9917 (3)	0.6206 (2)	0.0432 (11)
H7	0.4511	0.9430	0.6635	0.052*
C8	0.2216 (5)	0.9560 (4)	0.6100 (2)	0.0482 (11)
H8A	0.1534	1.0230	0.6240	0.058*
H8B	0.2026	0.9393	0.5546	0.058*
C9	0.1633 (7)	0.8502 (4)	0.6583 (2)	0.0534 (12)
H9A	0.0630	0.8198	0.6344	0.064*
H9B	0.2467	0.7892	0.6547	0.064*
C10	0.1297 (5)	0.8741 (3)	0.7439 (2)	0.0427 (10)
C11	0.5160 (6)	0.9655 (4)	0.5473 (2)	0.0539 (12)
H11	0.4710	1.0109	0.5031	0.065*
C12	0.6958 (6)	1.0003 (6)	0.5569 (3)	0.090 (2)
H12A	0.7404	0.9632	0.6031	0.134*
H12B	0.7036	1.0841	0.5625	0.134*
H12C	0.7572	0.9758	0.5114	0.134*
C13	0.5033 (9)	0.8344 (4)	0.5254 (3)	0.088 (2)
H13A	0.3915	0.8162	0.5108	0.133*
H13B	0.5348	0.7874	0.5700	0.133*
H13C	0.5756	0.8179	0.4819	0.133*
C14	−0.0276 (6)	0.9371 (4)	0.7621 (3)	0.0664 (14)
H14A	−0.0342	1.0073	0.7309	0.100*
H14B	−0.0299	0.9575	0.8171	0.100*
H14C	−0.1198	0.8870	0.7502	0.100*
C15	0.5860 (6)	1.0613 (4)	0.8082 (2)	0.0536 (12)
H15A	0.6288	1.0823	0.8592	0.080*
H15B	0.6530	1.0965	0.7679	0.080*
H15C	0.5878	0.9774	0.8024	0.080*
H4	−0.133 (8)	0.744 (5)	0.935 (3)	0.09 (2)*
H4C	0.024 (6)	0.740 (4)	0.900 (3)	0.069 (15)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.065 (2)	0.0368 (15)	0.0480 (15)	−0.0061 (14)	0.0068 (15)	−0.0068 (13)
O2	0.061 (2)	0.0475 (18)	0.0531 (17)	0.0085 (16)	0.0069 (16)	0.0150 (14)
O3	0.065 (2)	0.0356 (15)	0.0556 (16)	−0.0072 (14)	0.0096 (16)	0.0006 (14)
O4	0.059 (3)	0.089 (3)	0.058 (2)	−0.023 (2)	0.0027 (19)	−0.021 (2)
C1	0.049 (3)	0.033 (2)	0.039 (2)	−0.0066 (19)	0.010 (2)	−0.0017 (18)
C2	0.068 (3)	0.046 (3)	0.038 (2)	−0.009 (2)	0.013 (2)	−0.0009 (19)
C3	0.068 (3)	0.049 (3)	0.042 (2)	−0.009 (2)	0.017 (2)	−0.011 (2)
C4	0.055 (3)	0.034 (2)	0.037 (2)	−0.003 (2)	0.006 (2)	−0.0017 (17)
C5	0.039 (2)	0.038 (2)	0.042 (2)	−0.0011 (18)	0.0045 (19)	−0.0060 (18)
C6	0.040 (3)	0.043 (2)	0.038 (2)	0.006 (2)	0.0017 (19)	0.0019 (18)
C7	0.058 (3)	0.042 (2)	0.0298 (17)	0.015 (2)	−0.0041 (19)	0.0029 (17)
C8	0.066 (3)	0.042 (2)	0.037 (2)	0.007 (2)	−0.014 (2)	−0.0026 (18)
C9	0.067 (3)	0.041 (3)	0.052 (3)	−0.002 (2)	−0.006 (2)	−0.002 (2)
C10	0.045 (3)	0.035 (2)	0.048 (2)	−0.0069 (19)	0.004 (2)	−0.0018 (18)
C11	0.071 (3)	0.058 (3)	0.033 (2)	0.020 (3)	−0.003 (2)	0.000 (2)
C12	0.058 (4)	0.138 (5)	0.073 (3)	0.026 (4)	0.018 (3)	−0.015 (4)
C13	0.147 (6)	0.067 (3)	0.051 (3)	0.042 (4)	0.007 (4)	−0.013 (2)
C14	0.046 (3)	0.056 (3)	0.097 (3)	−0.003 (2)	0.007 (3)	0.002 (3)
C15	0.055 (3)	0.060 (3)	0.046 (2)	−0.011 (2)	−0.006 (2)	−0.002 (2)

Geometric parameters (Å, º) top

O1—C5	1.450 (4)	C7—C8	1.568 (6)
O1—C4	1.464 (4)	C7—H7	0.9800
O2—C6	1.438 (4)	C8—C9	1.529 (5)
O2—H3	0.8200	C8—H8A	0.9700
O3—C1	1.467 (5)	C8—H8B	0.9700
O3—C10	1.481 (4)	C9—C10	1.501 (5)
O4—H4	0.94 (6)	C9—H9A	0.9700
O4—H4C	0.93 (4)	C9—H9B	0.9700
C1—C10	1.477 (6)	C10—C14	1.492 (6)
C1—C2	1.517 (5)	C11—C12	1.516 (7)
C1—H1	0.9800	C11—C13	1.541 (6)
C2—C3	1.536 (5)	C11—H11	0.9800
C2—H2A	0.9700	C12—H12A	0.9600
C2—H2B	0.9700	C12—H12B	0.9600
C3—C4	1.518 (5)	C12—H12C	0.9600
C3—H3A	0.9700	C13—H13A	0.9600
C3—H3B	0.9700	C13—H13B	0.9600
C4—C5	1.459 (5)	C13—H13C	0.9600
C4—C15	1.502 (6)	C14—H14A	0.9600
C5—C6	1.484 (5)	C14—H14B	0.9600
C5—H5	0.9800	C14—H14C	0.9600
C6—C7	1.545 (5)	C15—H15A	0.9600
C6—H6	0.9800	C15—H15B	0.9600
C7—C11	1.550 (6)	C15—H15C	0.9600

C5—O1—C4	60.1 (2)	C9—C8—C7	116.0 (3)
C6—O2—H3	109.5	C9—C8—H8A	108.3
C1—O3—C10	60.1 (2)	C7—C8—H8A	108.3
C1—O3—H4C	114.1 (12)	C9—C8—H8B	108.3
C10—O3—H4C	124.0 (13)	C7—C8—H8B	108.3
H4—O4—H4C	96 (4)	H8A—C8—H8B	107.4
O3—C1—C10	60.4 (2)	C10—C9—C8	115.4 (3)
O3—C1—C2	116.9 (3)	C10—C9—H9A	108.4
C10—C1—C2	124.6 (4)	C8—C9—H9A	108.4
O3—C1—H1	114.6	C10—C9—H9B	108.4
C10—C1—H1	114.6	C8—C9—H9B	108.4
C2—C1—H1	114.6	H9A—C9—H9B	107.5
C1—C2—C3	113.3 (3)	C1—C10—O3	59.4 (2)
C1—C2—H2A	108.9	C1—C10—C14	123.1 (3)
C3—C2—H2A	108.9	O3—C10—C14	112.3 (3)
C1—C2—H2B	108.9	C1—C10—C9	117.8 (4)
C3—C2—H2B	108.9	O3—C10—C9	113.4 (3)
H2A—C2—H2B	107.7	C14—C10—C9	116.2 (4)
C4—C3—C2	113.2 (3)	C12—C11—C13	110.1 (5)
C4—C3—H3A	108.9	C12—C11—C7	114.0 (4)
C2—C3—H3A	108.9	C13—C11—C7	110.0 (4)
C4—C3—H3B	108.9	C12—C11—H11	107.5
C2—C3—H3B	108.9	C13—C11—H11	107.5
H3A—C3—H3B	107.7	C7—C11—H11	107.5
C5—C4—O1	59.5 (2)	C11—C12—H12A	109.5
C5—C4—C15	121.8 (3)	C11—C12—H12B	109.5
O1—C4—C15	114.2 (4)	H12A—C12—H12B	109.5
C5—C4—C3	118.0 (4)	C11—C12—H12C	109.5
O1—C4—C3	113.5 (3)	H12A—C12—H12C	109.5
C15—C4—C3	116.2 (4)	H12B—C12—H12C	109.5
O1—C5—C4	60.5 (2)	C11—C13—H13A	109.5
O1—C5—C6	120.0 (3)	C11—C13—H13B	109.5
C4—C5—C6	124.1 (4)	H13A—C13—H13B	109.5
O1—C5—H5	114.0	C11—C13—H13C	109.5
C4—C5—H5	114.0	H13A—C13—H13C	109.5
C6—C5—H5	114.0	H13B—C13—H13C	109.5
O2—C6—C5	107.7 (3)	C10—C14—H14A	109.5
O2—C6—C7	112.4 (3)	C10—C14—H14B	109.5
C5—C6—C7	110.2 (3)	H14A—C14—H14B	109.5
O2—C6—H6	108.8	C10—C14—H14C	109.5
C5—C6—H6	108.8	H14A—C14—H14C	109.5
C7—C6—H6	108.8	H14B—C14—H14C	109.5
C6—C7—C11	111.6 (3)	C4—C15—H15A	109.5
C6—C7—C8	111.8 (3)	C4—C15—H15B	109.5
C11—C7—C8	113.7 (3)	H15A—C15—H15B	109.5
C6—C7—H7	106.4	C4—C15—H15C	109.5
C11—C7—H7	106.4	H15A—C15—H15C	109.5
C8—C7—H7	106.4	H15B—C15—H15C	109.5

H4C—O3—C1—C10	−116.7 (14)	O2—C6—C7—C8	−60.0 (4)
C10—O3—C1—C2	116.3 (4)	C5—C6—C7—C8	60.0 (4)
H4C—O3—C1—C2	−0.4 (14)	C6—C7—C8—C9	−123.0 (3)
O3—C1—C2—C3	−139.3 (4)	C11—C7—C8—C9	109.5 (4)
C10—C1—C2—C3	−68.2 (5)	C7—C8—C9—C10	77.7 (5)
C1—C2—C3—C4	−42.3 (6)	C2—C1—C10—O3	−104.0 (4)
C5—O1—C4—C15	113.9 (4)	O3—C1—C10—C14	98.1 (4)
C5—O1—C4—C3	−109.7 (4)	C2—C1—C10—C14	−5.8 (6)
C2—C3—C4—C5	100.5 (5)	O3—C1—C10—C9	−102.2 (4)
C2—C3—C4—O1	167.1 (4)	C2—C1—C10—C9	153.9 (4)
C2—C3—C4—C15	−57.4 (5)	H4C—O3—C10—C1	100.5 (15)
C4—O1—C5—C6	−114.7 (4)	C1—O3—C10—C14	−116.3 (4)
C15—C4—C5—O1	−101.2 (4)	H4C—O3—C10—C14	−15.8 (15)
C3—C4—C5—O1	102.2 (4)	C1—O3—C10—C9	109.5 (4)
O1—C4—C5—C6	108.0 (4)	H4C—O3—C10—C9	−150.0 (15)
C15—C4—C5—C6	6.8 (6)	C8—C9—C10—C1	−85.0 (5)
C3—C4—C5—C6	−149.8 (4)	C8—C9—C10—O3	−151.5 (4)
O1—C5—C6—O2	−84.7 (4)	C8—C9—C10—C14	76.1 (5)
C4—C5—C6—O2	−157.4 (3)	C6—C7—C11—C12	52.2 (5)
O1—C5—C6—C7	152.4 (3)	C8—C7—C11—C12	179.8 (4)
C4—C5—C6—C7	79.7 (5)	C6—C7—C11—C13	176.3 (4)
O2—C6—C7—C11	68.5 (4)	C8—C7—C11—C13	−56.2 (5)
C5—C6—C7—C11	−171.4 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H3···O4ⁱ	0.82	2.03	2.819 (4)	160
O4—H4···O2ⁱⁱ	0.94 (6)	1.92 (6)	2.836 (5)	164 (5)
O4—H4C···O3	0.93 (4)	2.10 (5)	3.013 (4)	166 (4)

Symmetry codes: (i) −x+1/2, −y+2, z−1/2; (ii) −x, y−1/2, −z+3/2.

Experimental details

Crystal data
Chemical formula	C₁₅H₂₆O₃·H₂O
M_r	272.37
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	293
a, b, c (Å)	8.087 (2), 11.380 (3), 16.943 (5)
V (Å³)	1559.2 (8)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.31 × 0.13 × 0.07

Data collection
Diffractometer	Bruker SMART CCD area-detector
Absorption correction	Multi-scan (SADABS; Sheldrick, 2000)
T_min, T_max	0.757, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	8291, 1759, 1281
R_int	0.080
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.062, 0.148, 1.06
No. of reflections	1759
No. of parameters	186
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.16, −0.15

Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H3···O4ⁱ	0.82	2.03	2.819 (4)	159.9
O4—H4···O2ⁱⁱ	0.94 (6)	1.92 (6)	2.836 (5)	164 (5)
O4—H4C···O3	0.93 (4)	2.10 (5)	3.013 (4)	166 (4)

Symmetry codes: (i) −x+1/2, −y+2, z−1/2; (ii) −x, y−1/2, −z+3/2.

Acknowledgements

This work was supported financially by a grant from the Guangdong Pharmaceutical University Foundation for Young Teachers.

References

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