Absolute configuration of micromelin

Fun, H.-K.; Siridechakorn, I.; Laphookhieo, S.; Chantrapromma, S.

doi:10.1107/S1600536811022720

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 67| Part 7| July 2011| Pages o1706-o1707

doi:10.1107/S1600536811022720

Open

access

Absolute configuration of micromelin

Hoong-Kun Fun,^a ^*‡ Ittipon Siridechakorn,^b Surat Laphookhieo ^b and Suchada Chantrapromma ^c §

^aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, ^bNatural Products Research Laboratory, School of Science, Mae Fah Luang University, Tasud, Muang Chiang Rai 57100, Thailand, and ^cCrystal Materials Research Unit, Department of Chemistry, Faculty of Science, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand
^*Correspondence e-mail: hkfun@usm.my

(Received 4 June 2011; accepted 12 June 2011; online 18 June 2011)

The title compound {systematic name: 7-methoxy-6-[(1R,2R,5R)-5-methyl-4-oxo-3,6-dioxabicyclo[3.1.0]hexan-2-yl]-2H-chromen-2-one}, C₁₅H₁₂O₆, is a coumarin, which was isolated from the roots of Micromelum glanduliferum. There are two molecules in the asymmetric unit with slight differences in bond angles. In both molecules, the furan ring adopts a flattened envelope conformation. In the crystal, molecules are linked by weak C—H⋯O interactions into chains along the a axis. Aromatic π–π stacking interactions with centroid–centroid distances in the range 3.6995 (11)–3.8069 (11) Å and C⋯O short contacts [3.030 (2)–3.171 (3) Å] also occur.

Related literature

For bond-length data, see: Allen et al. (1987 ). For ring conformations, see: Cremer & Pople (1975 ). For background to plants in the Rutaceae family, coumarins and their activities, see: Ito et al. (1997 , 2000 ); Kamperdick et al. (1999 ); Rahmani et al. (2003 ); Tangyuenyongwatthana et al. (1992 ); Tantishaiyakul et al. (1986 ); Tantivatana et al. (1983 ); Thuy et al. (1999 ). For the stability of the temperature controller used in the data collection, see Cosier & Glazer, (1986 ).

Experimental

Crystal data

C₁₅H₁₂O₆
M_r = 288.25
Monoclinic, P 2₁
a = 6.7514 (2) Å
b = 23.7537 (8) Å
c = 8.0730 (3) Å
β = 90.000 (1)°
V = 1294.67 (8) Å³
Z = 4
Cu Kα radiation
μ = 0.98 mm⁻¹
T = 100 K
0.56 × 0.22 × 0.19 mm

Data collection

Bruker APEX DUO CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.609, T_max = 0.838
21511 measured reflections
4392 independent reflections
4392 reflections with I > 2σ(I)
R_int = 0.028

Refinement

R[F² > 2σ(F²)] = 0.022
wR(F²) = 0.059
S = 1.06
4392 reflections
384 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.13 e Å⁻³
Δρ_min = −0.13 e Å⁻³
Absolute structure: Flack (1983 ), 2632 Friedel pairs
Flack parameter: 0.06 (10)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C3B—H3B⋯O4Aⁱ	0.93	2.60	3.450 (2)	152
C5A—H5A⋯O2Aⁱⁱ	0.93	2.60	3.518 (3)	171
C5B—H5B⋯O2Bⁱⁱⁱ	0.93	2.57	3.493 (2)	173
C8A—H8A⋯O5Aⁱⁱⁱ	0.93	2.58	3.440 (3)	155
C8B—H8B⋯O5Bⁱⁱ	0.93	2.42	3.298 (3)	157
C10A—H10A⋯O2B	0.98	2.35	3.186 (2)	142
C10B—H10B⋯O2A^iv	0.98	2.29	3.171 (3)	150
C14B—H14E⋯O4A^v	0.96	2.49	3.423 (3)	163
C15B—H15D⋯O4A^v	0.96	2.46	3.405 (2)	166
Symmetry codes: (i) x-1, y, z-1; (ii) x, y, z+1; (iii) x, y, z-1; (iv) x-1, y, z; (v) $[-x+1, y-{\script{1\over 2}}, -z+1]$ .

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811022720/hb5904sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811022720/hb5904Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811022720/hb5904Isup3.cml

checkCIF report

Comment top

Coumarins are important secondary metabolites which occur commonly in the Rutaceae family. Many of them have been isolated from several genera of Rutaceae especially from Micromelum and Clausena genera (Ito et al., 1997; 2000; Kamperdick et al., 1999; Rahmani et al., 2003; Tangyuenyongwatthana et al., 1992; Tantishaiyakul et al., 1986; Thuy et al., 1999) and some of these compounds show interesting biological activities (Tantishaiyakul et al., 1986; Tantivatana et al., 1983). Although Micromelum glanduliferum is one of Rutaceae plants, however, no phytochemical investigation has been reported. As part of our continuing studies of the phytochemical constituents and bioactive compounds in Thai medicinal plants, we report herein the crystal structure of the title compound which was isolated from the roots of M. glanduliferum which were collected from Nongkai Province in the northeastern part of Thailand.

There are two crystallograpic independent molecules A and B in the asymmetric unit of (I), C₁₅H₁₂O₆, (Fig. 1) with the same conformation but with slight differences in bond angles. In the structure of (I), the furan ring (C10–C13/O3) is in a flattened envelope conformation with the puckering atom O3 of 0.064 (1) Å, and puckering parameter Q = 0.0991 (18) Å and ϕ = 9.2 (11)° (Cremer & Pople, 1975) for molecule A and the corresponding values are -0.053 (1) Å, 0.0820 (19) Å and ϕ = 10.1 (15)° for molecule B. The benzene and dihydro-pyran ring system (C1–C9/O1) is planar with the r.m.s. 0.0089 (2) Å for molecule A [0.0149 (2) Å for molecule B]. The methoxy group is almost planarly attached to the benzene ring with the torsion angle C15–O6–C7–C8 = 2.3 (3)° for molecule A and 2.6 (3)° for molecule B. The orientation of the oxirane ring (C10–C13–O5) can be indicated by the dihedral angle between the furan and oxirane rings being 79.46 (15)° for molecule A [79.48 (16)° for molecule B]. The bond distances in (I) are within normal ranges (Allen et al., 1987). The absolute configuration at atoms C10, C11 and C13 or positions 1, 2 and 5 of the micromelin are R,R,R configurations.

In the crystal (Fig. 2), molecules are linked by C—H···O weak interactions into 2D chains along the a axis. π–π interactions were observed with centroid···centroid distances: Cg₁···Cg₃ = 3.7698 (7) Å; Cg₂···Cg₅ = 3.7102 (11) Å; Cg₃···Cg₄ = 3.6995 (11) Å and 3.7666 (11) Å (symmetry code: 1+x, y, z); Cg₁, Cg₂, Cg₃, Cg₄ and Cg₅ are the centroids of C10A–C13A/O3A, C1A–C4A/C9A/O1A, C4A–C9A, C1B–C4B/C9B/O1B and C4B–C9B rings, respectively. C···O [3.030 (2)-3.171 (3) Å] short contacts were also observed.

Related literature top

For bond-length data, see: Allen et al. (1987). For ring conformations, see: Cremer & Pople (1975). For background to plants in the Rutaceae family, coumarins and their activities, see: Ito et al. (1997, 2000); Kamperdick et al. (1999); Rahmani et al. (2003); Tangyuenyongwatthana et al. (1992); Tantishaiyakul et al. (1986); Tantivatana et al. (1983); Thuy et al. (1999). For the stability of the temperature controller used in the data collection, see Cosier & Glazer, (1986).

Experimental top

The chemical contents of the roots of M. glanduliferum (5.25 kg) were successively extracted with CH₂Cl₂ over the period of 3 days at room temperature. Removal the solvent under reduced pressure provided CH₂Cl₂ extract which were subjected to quick column chromatography (QCC) over silica gel and eluted with a gradient of n-hexane-EtOAc (100% n-hexane to 100% EtOAc) to provide nine fractions (A-I). Fraction F (6.23 g) was washed with n-hexane and recrystallized from CH₂Cl₂/CH₃OH (1:4 v/v) to give colourless needles of the title compound. Mp 491.0-492.2 K (decompose).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The structure of (I), showing 50% probability displacement ellipsoids.
	Fig. 2. The crystal packing of (I) viewed along the c axis. Hydrogen bonds are shown as dashed lines.

7-Methoxy-6-[(1R,2R,5R)-5-methyl-4-oxo-3,6- dioxabicyclo[3.1.0]hexan-2-yl]-2H-chromen-2-one top

Crystal data top

C₁₅H₁₂O₆	F(000) = 600
M_r = 288.25	D_x = 1.479 Mg m⁻³
Monoclinic, P2₁	Melting point = 491.0–492.2 (decompose) K
Hall symbol: P 2yb	Cu Kα radiation, λ = 1.54178 Å
a = 6.7514 (2) Å	Cell parameters from 4392 reflections
b = 23.7537 (8) Å	θ = 1.9–67.5°
c = 8.0730 (3) Å	µ = 0.98 mm⁻¹
β = 90.000 (1)°	T = 100 K
V = 1294.67 (8) Å³	Needle, colorless
Z = 4	0.56 × 0.22 × 0.19 mm

Data collection top

Bruker APEX DUO CCD diffractometer	4392 independent reflections
Radiation source: sealed tube	4392 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.028
ϕ and ω scans	θ_max = 67.5°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −8→8
T_min = 0.609, T_max = 0.838	k = −28→28
21511 measured reflections	l = −7→9

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)] = 0.022	H-atom parameters constrained
wR(F²) = 0.059
S = 1.06	(Δ/σ)_max = 0.001
4392 reflections	Δρ_max = 0.13 e Å⁻³
384 parameters	Δρ_min = −0.13 e Å⁻³
1 restraint	Absolute structure: Flack (1983), 2632 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.06 (10)

Crystal data top

C₁₅H₁₂O₆	V = 1294.67 (8) Å³
M_r = 288.25	Z = 4
Monoclinic, P2₁	Cu Kα radiation
a = 6.7514 (2) Å	µ = 0.98 mm⁻¹
b = 23.7537 (8) Å	T = 100 K
c = 8.0730 (3) Å	0.56 × 0.22 × 0.19 mm
β = 90.000 (1)°

Data collection top

Bruker APEX DUO CCD diffractometer	4392 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	4392 reflections with I > 2σ(I)
T_min = 0.609, T_max = 0.838	R_int = 0.028
21511 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.022	H-atom parameters constrained
wR(F²) = 0.059	Δρ_max = 0.13 e Å⁻³
S = 1.06	Δρ_min = −0.13 e Å⁻³
4392 reflections	Absolute structure: Flack (1983), 2632 Friedel pairs
384 parameters	Absolute structure parameter: 0.06 (10)
1 restraint

Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
O1A	0.5534 (2)	0.77310 (5)	0.20837 (17)	0.0204 (3)
O2A	0.5534 (2)	0.70240 (6)	0.03012 (18)	0.0264 (3)
O3A	0.74087 (18)	0.88672 (5)	0.89684 (16)	0.0216 (3)
O4A	0.8825 (2)	0.97077 (5)	0.92773 (18)	0.0269 (3)
O5A	0.4227 (2)	0.93361 (5)	1.05332 (16)	0.0241 (3)
O6A	0.5758 (2)	0.93052 (5)	0.57220 (16)	0.0241 (3)
C1A	0.5487 (3)	0.71597 (7)	0.1741 (2)	0.0202 (4)
C2A	0.5373 (2)	0.67836 (8)	0.3155 (3)	0.0214 (4)
H2A	0.5333	0.6397	0.2974	0.026*
C3A	0.5323 (3)	0.69786 (8)	0.4722 (2)	0.0201 (4)
H3A	0.5235	0.6727	0.5602	0.024*
C4A	0.5405 (3)	0.75717 (7)	0.5038 (2)	0.0181 (4)
C5A	0.5383 (3)	0.78164 (8)	0.6622 (3)	0.0181 (4)
H5A	0.5292	0.7584	0.7546	0.022*
C6A	0.5493 (3)	0.83936 (7)	0.6845 (2)	0.0195 (4)
C7A	0.5631 (3)	0.87404 (7)	0.5419 (2)	0.0189 (4)
C8A	0.5625 (3)	0.85146 (8)	0.3842 (3)	0.0195 (4)
H8A	0.5690	0.8746	0.2914	0.023*
C9A	0.5519 (3)	0.79334 (8)	0.3677 (2)	0.0182 (4)
C10A	0.4044 (3)	0.91242 (8)	0.8848 (2)	0.0211 (4)
H10A	0.2787	0.9151	0.8246	0.025*
C11A	0.5444 (3)	0.86343 (7)	0.8562 (2)	0.0215 (4)
H11A	0.5128	0.8333	0.9349	0.026*
C12A	0.7343 (3)	0.94293 (7)	0.9141 (2)	0.0212 (3)
C13A	0.5240 (3)	0.96269 (8)	0.9180 (2)	0.0225 (4)
C14A	0.4710 (3)	1.02263 (7)	0.8862 (2)	0.0281 (4)
H14A	0.3296	1.0268	0.8891	0.042*
H14B	0.5195	1.0337	0.7793	0.042*
H14C	0.5297	1.0460	0.9698	0.042*
C15A	0.5814 (3)	0.96784 (8)	0.4322 (2)	0.0272 (4)
H15A	0.5919	1.0060	0.4703	0.041*
H15B	0.4623	0.9635	0.3686	0.041*
H15C	0.6938	0.9589	0.3643	0.041*
O1B	0.05200 (18)	0.79463 (5)	0.46409 (16)	0.0183 (3)
O2B	0.0717 (2)	0.86476 (5)	0.64252 (16)	0.0242 (3)
O3B	0.23060 (19)	0.67681 (5)	−0.22314 (17)	0.0233 (3)
O4B	0.34079 (19)	0.58955 (6)	−0.2685 (2)	0.0318 (3)
O5B	−0.09923 (19)	0.64242 (5)	−0.38897 (15)	0.0236 (3)
O6B	0.04861 (19)	0.63788 (5)	0.09768 (17)	0.0225 (3)
C1B	0.0630 (3)	0.85163 (7)	0.4988 (2)	0.0203 (4)
C2B	0.0651 (3)	0.88964 (7)	0.3574 (2)	0.0199 (4)
H2B	0.0720	0.9282	0.3761	0.024*
C3B	0.0575 (3)	0.87071 (7)	0.2008 (2)	0.0197 (4)
H3B	0.0557	0.8961	0.1131	0.024*
C4B	0.0519 (3)	0.81105 (8)	0.1684 (2)	0.0178 (4)
C5B	0.0489 (3)	0.78703 (8)	0.0093 (2)	0.0199 (4)
H5B	0.0482	0.8104	−0.0831	0.024*
C6B	0.0471 (3)	0.72951 (8)	−0.0123 (2)	0.0194 (4)
C7B	0.0466 (3)	0.69415 (7)	0.1295 (2)	0.0192 (4)
C8B	0.0462 (3)	0.71642 (7)	0.2875 (3)	0.0175 (3)
H8B	0.0440	0.6931	0.3801	0.021*
C9B	0.0491 (3)	0.77488 (7)	0.3041 (2)	0.0179 (4)
C10B	−0.1127 (3)	0.66169 (7)	−0.2188 (3)	0.0215 (4)
H10B	−0.2398	0.6622	−0.1602	0.026*
C11B	0.0431 (3)	0.70558 (9)	−0.1849 (2)	0.0228 (4)
H11B	0.0254	0.7366	−0.2636	0.027*
C12B	0.2048 (3)	0.62152 (8)	−0.2490 (2)	0.0226 (4)
C13B	−0.0122 (3)	0.60858 (8)	−0.2562 (2)	0.0207 (4)
C14B	−0.0890 (3)	0.55004 (8)	−0.2368 (3)	0.0278 (4)
H14D	−0.2311	0.5507	−0.2342	0.042*
H14E	−0.0399	0.5343	−0.1353	0.042*
H14F	−0.0453	0.5275	−0.3284	0.042*
C15B	0.0417 (3)	0.60079 (7)	0.2381 (2)	0.0223 (4)
H15D	0.0417	0.5624	0.2007	0.033*
H15E	−0.0765	0.6079	0.3007	0.033*
H15F	0.1555	0.6072	0.3069	0.033*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1A	0.0222 (6)	0.0233 (7)	0.0158 (7)	0.0021 (5)	−0.0004 (5)	−0.0002 (5)
O2A	0.0267 (7)	0.0324 (7)	0.0201 (8)	0.0025 (6)	−0.0010 (6)	−0.0059 (6)
O3A	0.0261 (6)	0.0169 (5)	0.0217 (7)	−0.0002 (5)	−0.0085 (6)	−0.0002 (5)
O4A	0.0280 (7)	0.0249 (6)	0.0278 (8)	−0.0054 (5)	−0.0071 (6)	−0.0003 (5)
O5A	0.0309 (7)	0.0241 (6)	0.0171 (6)	−0.0045 (5)	0.0002 (5)	−0.0034 (5)
O6A	0.0348 (7)	0.0188 (6)	0.0188 (7)	−0.0023 (5)	−0.0023 (6)	0.0039 (5)
C1A	0.0148 (8)	0.0238 (9)	0.0219 (11)	0.0021 (7)	−0.0029 (7)	−0.0024 (7)
C2A	0.0169 (8)	0.0224 (8)	0.0248 (10)	−0.0003 (7)	−0.0031 (7)	−0.0036 (7)
C3A	0.0148 (8)	0.0233 (9)	0.0223 (11)	−0.0016 (7)	−0.0022 (7)	0.0022 (7)
C4A	0.0138 (8)	0.0209 (9)	0.0197 (9)	−0.0004 (6)	−0.0014 (7)	0.0021 (7)
C5A	0.0149 (8)	0.0194 (8)	0.0201 (9)	−0.0013 (6)	−0.0030 (7)	0.0050 (6)
C6A	0.0174 (8)	0.0210 (9)	0.0202 (10)	−0.0014 (7)	−0.0064 (7)	0.0011 (7)
C7A	0.0172 (8)	0.0193 (9)	0.0202 (10)	−0.0008 (7)	−0.0029 (7)	0.0035 (7)
C8A	0.0173 (8)	0.0232 (9)	0.0179 (9)	0.0001 (7)	−0.0019 (7)	0.0045 (7)
C9A	0.0126 (8)	0.0243 (9)	0.0178 (10)	0.0007 (7)	−0.0013 (8)	0.0004 (7)
C10A	0.0265 (8)	0.0225 (8)	0.0142 (9)	−0.0010 (8)	−0.0023 (7)	−0.0007 (7)
C11A	0.0248 (8)	0.0204 (9)	0.0193 (10)	−0.0049 (7)	−0.0051 (8)	0.0039 (7)
C12A	0.0297 (9)	0.0212 (8)	0.0127 (9)	−0.0039 (7)	−0.0063 (7)	0.0037 (6)
C13A	0.0298 (9)	0.0233 (8)	0.0143 (9)	−0.0020 (8)	−0.0036 (7)	0.0011 (7)
C14A	0.0325 (10)	0.0261 (10)	0.0258 (10)	0.0044 (8)	0.0000 (8)	−0.0006 (7)
C15A	0.0388 (11)	0.0206 (8)	0.0222 (10)	−0.0016 (8)	0.0005 (8)	0.0067 (7)
O1B	0.0193 (6)	0.0204 (6)	0.0153 (7)	0.0001 (5)	−0.0028 (5)	−0.0005 (5)
O2B	0.0288 (7)	0.0248 (7)	0.0192 (7)	−0.0029 (6)	−0.0037 (5)	−0.0047 (5)
O3B	0.0241 (6)	0.0253 (6)	0.0205 (7)	−0.0007 (5)	0.0035 (5)	−0.0015 (5)
O4B	0.0288 (7)	0.0317 (7)	0.0349 (8)	0.0085 (6)	0.0011 (6)	−0.0057 (6)
O5B	0.0318 (7)	0.0250 (6)	0.0139 (6)	0.0045 (5)	−0.0027 (5)	−0.0007 (5)
O6B	0.0306 (7)	0.0187 (6)	0.0181 (7)	0.0036 (5)	−0.0002 (6)	0.0005 (5)
C1B	0.0145 (8)	0.0204 (8)	0.0261 (12)	−0.0001 (7)	−0.0020 (7)	−0.0038 (7)
C2B	0.0171 (8)	0.0168 (8)	0.0259 (10)	−0.0012 (7)	−0.0040 (7)	−0.0007 (7)
C3B	0.0154 (8)	0.0204 (8)	0.0232 (10)	−0.0007 (7)	−0.0019 (8)	0.0027 (7)
C4B	0.0141 (8)	0.0191 (9)	0.0202 (10)	0.0007 (6)	−0.0027 (7)	0.0029 (7)
C5B	0.0186 (8)	0.0239 (9)	0.0172 (9)	0.0020 (7)	−0.0001 (7)	0.0037 (7)
C6B	0.0184 (8)	0.0212 (9)	0.0185 (10)	0.0031 (7)	−0.0023 (8)	0.0003 (7)
C7B	0.0166 (8)	0.0178 (8)	0.0231 (10)	0.0028 (7)	−0.0018 (7)	−0.0016 (7)
C8B	0.0163 (7)	0.0177 (8)	0.0184 (9)	0.0028 (6)	−0.0018 (7)	0.0054 (6)
C9B	0.0157 (8)	0.0221 (9)	0.0161 (9)	0.0005 (7)	−0.0021 (7)	−0.0026 (7)
C10B	0.0253 (9)	0.0258 (9)	0.0133 (9)	0.0044 (7)	−0.0019 (7)	−0.0013 (6)
C11B	0.0284 (9)	0.0226 (9)	0.0173 (10)	0.0050 (8)	0.0007 (8)	0.0007 (7)
C12B	0.0295 (9)	0.0239 (9)	0.0145 (10)	0.0013 (7)	0.0005 (7)	0.0008 (7)
C13B	0.0255 (8)	0.0238 (9)	0.0127 (10)	0.0033 (7)	−0.0010 (7)	0.0009 (7)
C14B	0.0339 (10)	0.0252 (9)	0.0243 (10)	−0.0033 (8)	−0.0034 (9)	−0.0007 (7)
C15B	0.0284 (8)	0.0188 (8)	0.0197 (9)	0.0032 (7)	−0.0017 (8)	0.0021 (7)

Geometric parameters (Å, º) top

O1A—C9A	1.373 (2)	O1B—C9B	1.374 (2)
O1A—C1A	1.385 (2)	O1B—C1B	1.385 (2)
O2A—C1A	1.207 (2)	O2B—C1B	1.203 (2)
O3A—C12A	1.343 (2)	O3B—C12B	1.341 (2)
O3A—C11A	1.474 (2)	O3B—C11B	1.471 (2)
O4A—C12A	1.204 (2)	O4B—C12B	1.202 (2)
O5A—C10A	1.456 (2)	O5B—C10B	1.451 (2)
O5A—C13A	1.462 (2)	O5B—C13B	1.463 (2)
O6A—C7A	1.366 (2)	O6B—C7B	1.361 (2)
O6A—C15A	1.437 (2)	O6B—C15B	1.437 (2)
C1A—C2A	1.451 (3)	C1B—C2B	1.455 (3)
C2A—C3A	1.348 (3)	C2B—C3B	1.343 (3)
C2A—H2A	0.9300	C2B—H2B	0.9300
C3A—C4A	1.433 (2)	C3B—C4B	1.441 (2)
C3A—H3A	0.9300	C3B—H3B	0.9300
C4A—C9A	1.397 (3)	C4B—C9B	1.392 (2)
C4A—C5A	1.405 (3)	C4B—C5B	1.406 (3)
C5A—C6A	1.385 (2)	C5B—C6B	1.377 (3)
C5A—H5A	0.9300	C5B—H5B	0.9300
C6A—C7A	1.419 (2)	C6B—C7B	1.420 (3)
C6A—C11A	1.500 (3)	C6B—C11B	1.505 (3)
C7A—C8A	1.381 (3)	C7B—C8B	1.381 (3)
C8A—C9A	1.389 (3)	C8B—C9B	1.395 (2)
C8A—H8A	0.9300	C8B—H8B	0.9300
C10A—C13A	1.466 (3)	C10B—C13B	1.464 (3)
C10A—C11A	1.517 (3)	C10B—C11B	1.506 (3)
C10A—H10A	0.9800	C10B—H10B	0.9800
C11A—H11A	0.9800	C11B—H11B	0.9800
C12A—C13A	1.496 (3)	C12B—C13B	1.498 (2)
C13A—C14A	1.490 (2)	C13B—C14B	1.492 (2)
C14A—H14A	0.9600	C14B—H14D	0.9600
C14A—H14B	0.9600	C14B—H14E	0.9600
C14A—H14C	0.9600	C14B—H14F	0.9600
C15A—H15A	0.9600	C15B—H15D	0.9600
C15A—H15B	0.9600	C15B—H15E	0.9600
C15A—H15C	0.9600	C15B—H15F	0.9600

C9A—O1A—C1A	121.99 (14)	C9B—O1B—C1B	121.63 (13)
C12A—O3A—C11A	111.50 (14)	C12B—O3B—C11B	112.06 (15)
C10A—O5A—C13A	60.32 (11)	C10B—O5B—C13B	60.31 (11)
C7A—O6A—C15A	117.82 (14)	C7B—O6B—C15B	116.94 (15)
O2A—C1A—O1A	116.95 (16)	O2B—C1B—O1B	116.82 (16)
O2A—C1A—C2A	126.46 (16)	O2B—C1B—C2B	126.52 (16)
O1A—C1A—C2A	116.58 (16)	O1B—C1B—C2B	116.66 (16)
C3A—C2A—C1A	121.86 (17)	C3B—C2B—C1B	122.02 (16)
C3A—C2A—H2A	119.1	C3B—C2B—H2B	119.0
C1A—C2A—H2A	119.1	C1B—C2B—H2B	119.0
C2A—C3A—C4A	120.27 (17)	C2B—C3B—C4B	120.06 (16)
C2A—C3A—H3A	119.9	C2B—C3B—H3B	120.0
C4A—C3A—H3A	119.9	C4B—C3B—H3B	120.0
C9A—C4A—C5A	117.51 (16)	C9B—C4B—C5B	117.92 (16)
C9A—C4A—C3A	117.85 (18)	C9B—C4B—C3B	117.67 (17)
C5A—C4A—C3A	124.65 (16)	C5B—C4B—C3B	124.41 (16)
C6A—C5A—C4A	121.84 (18)	C6B—C5B—C4B	121.22 (17)
C6A—C5A—H5A	119.1	C6B—C5B—H5B	119.4
C4A—C5A—H5A	119.1	C4B—C5B—H5B	119.4
C5A—C6A—C7A	118.23 (17)	C5B—C6B—C7B	119.00 (17)
C5A—C6A—C11A	119.76 (17)	C5B—C6B—C11B	119.47 (17)
C7A—C6A—C11A	122.01 (15)	C7B—C6B—C11B	121.53 (16)
O6A—C7A—C8A	123.13 (16)	O6B—C7B—C8B	123.40 (16)
O6A—C7A—C6A	115.41 (15)	O6B—C7B—C6B	115.39 (16)
C8A—C7A—C6A	121.47 (16)	C8B—C7B—C6B	121.20 (16)
C7A—C8A—C9A	118.33 (16)	C7B—C8B—C9B	118.02 (16)
C7A—C8A—H8A	120.8	C7B—C8B—H8B	121.0
C9A—C8A—H8A	120.8	C9B—C8B—H8B	121.0
O1A—C9A—C8A	115.95 (15)	O1B—C9B—C4B	121.91 (16)
O1A—C9A—C4A	121.44 (16)	O1B—C9B—C8B	115.46 (15)
C8A—C9A—C4A	122.62 (17)	C4B—C9B—C8B	122.62 (17)
O5A—C10A—C13A	60.06 (12)	O5B—C10B—C13B	60.26 (12)
O5A—C10A—C11A	110.76 (14)	O5B—C10B—C11B	110.29 (15)
C13A—C10A—C11A	108.03 (15)	C13B—C10B—C11B	108.09 (15)
O5A—C10A—H10A	120.9	O5B—C10B—H10B	121.0
C13A—C10A—H10A	120.9	C13B—C10B—H10B	121.0
C11A—C10A—H10A	120.9	C11B—C10B—H10B	121.0
O3A—C11A—C6A	109.19 (15)	O3B—C11B—C6B	110.73 (15)
O3A—C11A—C10A	103.82 (14)	O3B—C11B—C10B	103.96 (15)
C6A—C11A—C10A	116.54 (15)	C6B—C11B—C10B	116.25 (17)
O3A—C11A—H11A	109.0	O3B—C11B—H11B	108.5
C6A—C11A—H11A	109.0	C6B—C11B—H11B	108.5
C10A—C11A—H11A	109.0	C10B—C11B—H11B	108.5
O4A—C12A—O3A	121.87 (16)	O4B—C12B—O3B	122.68 (18)
O4A—C12A—C13A	127.90 (16)	O4B—C12B—C13B	127.76 (17)
O3A—C12A—C13A	110.21 (15)	O3B—C12B—C13B	109.51 (16)
O5A—C13A—C10A	59.62 (11)	O5B—C13B—C10B	59.43 (11)
O5A—C13A—C14A	117.86 (16)	O5B—C13B—C14B	116.71 (15)
C10A—C13A—C14A	127.90 (17)	C10B—C13B—C14B	128.36 (16)
O5A—C13A—C12A	108.14 (14)	O5B—C13B—C12B	107.97 (15)
C10A—C13A—C12A	105.27 (15)	C10B—C13B—C12B	105.57 (15)
C14A—C13A—C12A	121.63 (16)	C14B—C13B—C12B	121.78 (15)
C13A—C14A—H14A	109.5	C13B—C14B—H14D	109.5
C13A—C14A—H14B	109.5	C13B—C14B—H14E	109.5
H14A—C14A—H14B	109.5	H14D—C14B—H14E	109.5
C13A—C14A—H14C	109.5	C13B—C14B—H14F	109.5
H14A—C14A—H14C	109.5	H14D—C14B—H14F	109.5
H14B—C14A—H14C	109.5	H14E—C14B—H14F	109.5
O6A—C15A—H15A	109.5	O6B—C15B—H15D	109.5
O6A—C15A—H15B	109.5	O6B—C15B—H15E	109.5
H15A—C15A—H15B	109.5	H15D—C15B—H15E	109.5
O6A—C15A—H15C	109.5	O6B—C15B—H15F	109.5
H15A—C15A—H15C	109.5	H15D—C15B—H15F	109.5
H15B—C15A—H15C	109.5	H15E—C15B—H15F	109.5

C9A—O1A—C1A—O2A	−178.97 (17)	C9B—O1B—C1B—O2B	−177.49 (14)
C9A—O1A—C1A—C2A	1.4 (3)	C9B—O1B—C1B—C2B	1.9 (2)
O2A—C1A—C2A—C3A	−179.84 (19)	O2B—C1B—C2B—C3B	179.08 (18)
O1A—C1A—C2A—C3A	−0.3 (3)	O1B—C1B—C2B—C3B	−0.2 (2)
C1A—C2A—C3A—C4A	−0.7 (3)	C1B—C2B—C3B—C4B	−1.6 (3)
C2A—C3A—C4A—C9A	0.6 (3)	C2B—C3B—C4B—C9B	1.8 (3)
C2A—C3A—C4A—C5A	−179.32 (16)	C2B—C3B—C4B—C5B	−178.27 (16)
C9A—C4A—C5A—C6A	−0.8 (3)	C9B—C4B—C5B—C6B	−1.2 (3)
C3A—C4A—C5A—C6A	179.12 (16)	C3B—C4B—C5B—C6B	178.86 (17)
C4A—C5A—C6A—C7A	0.0 (3)	C4B—C5B—C6B—C7B	0.5 (3)
C4A—C5A—C6A—C11A	179.40 (16)	C4B—C5B—C6B—C11B	179.74 (17)
C15A—O6A—C7A—C8A	2.3 (3)	C15B—O6B—C7B—C8B	2.6 (3)
C15A—O6A—C7A—C6A	−177.34 (16)	C15B—O6B—C7B—C6B	−178.06 (14)
C5A—C6A—C7A—O6A	−179.27 (15)	C5B—C6B—C7B—O6B	−178.79 (15)
C11A—C6A—C7A—O6A	1.3 (3)	C11B—C6B—C7B—O6B	2.0 (3)
C5A—C6A—C7A—C8A	1.1 (3)	C5B—C6B—C7B—C8B	0.6 (3)
C11A—C6A—C7A—C8A	−178.34 (17)	C11B—C6B—C7B—C8B	−178.65 (17)
O6A—C7A—C8A—C9A	179.09 (16)	O6B—C7B—C8B—C9B	178.41 (14)
C6A—C7A—C8A—C9A	−1.3 (3)	C6B—C7B—C8B—C9B	−0.9 (3)
C1A—O1A—C9A—C8A	178.32 (14)	C1B—O1B—C9B—C4B	−1.7 (3)
C1A—O1A—C9A—C4A	−1.6 (3)	C1B—O1B—C9B—C8B	177.39 (14)
C7A—C8A—C9A—O1A	−179.47 (16)	C5B—C4B—C9B—O1B	179.89 (14)
C7A—C8A—C9A—C4A	0.4 (3)	C3B—C4B—C9B—O1B	−0.1 (3)
C5A—C4A—C9A—O1A	−179.54 (16)	C5B—C4B—C9B—C8B	0.8 (3)
C3A—C4A—C9A—O1A	0.6 (3)	C3B—C4B—C9B—C8B	−179.19 (14)
C5A—C4A—C9A—C8A	0.6 (3)	C7B—C8B—C9B—O1B	−178.93 (14)
C3A—C4A—C9A—C8A	−179.34 (16)	C7B—C8B—C9B—C4B	0.2 (3)
C13A—O5A—C10A—C11A	99.42 (16)	C13B—O5B—C10B—C11B	99.79 (16)
C12A—O3A—C11A—C6A	113.83 (16)	C12B—O3B—C11B—C6B	116.25 (18)
C12A—O3A—C11A—C10A	−11.11 (18)	C12B—O3B—C11B—C10B	−9.3 (2)
C5A—C6A—C11A—O3A	110.37 (17)	C5B—C6B—C11B—O3B	112.02 (18)
C7A—C6A—C11A—O3A	−70.2 (2)	C7B—C6B—C11B—O3B	−68.8 (2)
C5A—C6A—C11A—C10A	−132.47 (18)	C5B—C6B—C11B—C10B	−129.66 (19)
C7A—C6A—C11A—C10A	46.9 (2)	C7B—C6B—C11B—C10B	49.6 (2)
O5A—C10A—C11A—O3A	−56.68 (17)	O5B—C10B—C11B—O3B	−57.98 (18)
C13A—C10A—C11A—O3A	7.34 (19)	C13B—C10B—C11B—O3B	6.2 (2)
O5A—C10A—C11A—C6A	−176.76 (14)	O5B—C10B—C11B—C6B	−179.94 (14)
C13A—C10A—C11A—C6A	−112.74 (17)	C13B—C10B—C11B—C6B	−115.77 (19)
C11A—O3A—C12A—O4A	−170.99 (17)	C11B—O3B—C12B—O4B	−173.74 (18)
C11A—O3A—C12A—C13A	10.6 (2)	C11B—O3B—C12B—C13B	8.7 (2)
C10A—O5A—C13A—C14A	119.70 (18)	C10B—O5B—C13B—C14B	120.65 (18)
C10A—O5A—C13A—C12A	−97.43 (17)	C10B—O5B—C13B—C12B	−97.83 (16)
C11A—C10A—C13A—O5A	−104.05 (15)	C11B—C10B—C13B—O5B	−103.51 (16)
O5A—C10A—C13A—C14A	−103.3 (2)	O5B—C10B—C13B—C14B	−101.4 (2)
C11A—C10A—C13A—C14A	152.64 (19)	C11B—C10B—C13B—C14B	155.06 (19)
O5A—C10A—C13A—C12A	102.35 (16)	O5B—C10B—C13B—C12B	101.97 (16)
C11A—C10A—C13A—C12A	−1.7 (2)	C11B—C10B—C13B—C12B	−1.5 (2)
O4A—C12A—C13A—O5A	−121.19 (19)	O4B—C12B—C13B—O5B	−119.4 (2)
O3A—C12A—C13A—O5A	57.12 (19)	O3B—C12B—C13B—O5B	58.02 (19)
O4A—C12A—C13A—C10A	176.34 (19)	O4B—C12B—C13B—C10B	178.3 (2)
O3A—C12A—C13A—C10A	−5.3 (2)	O3B—C12B—C13B—C10B	−4.3 (2)
O4A—C12A—C13A—C14A	20.0 (3)	O4B—C12B—C13B—C14B	19.8 (3)
O3A—C12A—C13A—C14A	−161.68 (15)	O3B—C12B—C13B—C14B	−162.80 (16)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3B—H3B···O4Aⁱ	0.93	2.60	3.450 (2)	152
C5A—H5A···O2Aⁱⁱ	0.93	2.60	3.518 (3)	171
C5B—H5B···O2Bⁱⁱⁱ	0.93	2.57	3.493 (2)	173
C8A—H8A···O5Aⁱⁱⁱ	0.93	2.58	3.440 (3)	155
C8B—H8B···O5Bⁱⁱ	0.93	2.42	3.298 (3)	157
C10A—H10A···O2B	0.98	2.35	3.186 (2)	142
C10B—H10B···O2A^iv	0.98	2.29	3.171 (3)	150
C14B—H14E···O4A^v	0.96	2.49	3.423 (3)	163
C15B—H15D···O4A^v	0.96	2.46	3.405 (2)	166

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

Experimental details

Crystal data
Chemical formula	C₁₅H₁₂O₆
M_r	288.25
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	100
a, b, c (Å)	6.7514 (2), 23.7537 (8), 8.0730 (3)
β (°)	90, 90.000 (1), 90
V (Å³)	1294.67 (8)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	0.98
Crystal size (mm)	0.56 × 0.22 × 0.19

Data collection
Diffractometer	Bruker APEX DUO CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.609, 0.838
No. of measured, independent and observed [I > 2σ(I)] reflections	21511, 4392, 4392
R_int	0.028
(sin θ/λ)_max (Å⁻¹)	0.599

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.022, 0.059, 1.06
No. of reflections	4392
No. of parameters	384
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.13, −0.13
Absolute structure	Flack (1983), 2632 Friedel pairs
Absolute structure parameter	0.06 (10)

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3B—H3B···O4Aⁱ	0.93	2.60	3.450 (2)	152
C5A—H5A···O2Aⁱⁱ	0.93	2.60	3.518 (3)	171
C5B—H5B···O2Bⁱⁱⁱ	0.93	2.57	3.493 (2)	173
C8A—H8A···O5Aⁱⁱⁱ	0.93	2.58	3.440 (3)	155
C8B—H8B···O5Bⁱⁱ	0.93	2.42	3.298 (3)	157
C10A—H10A···O2B	0.98	2.35	3.186 (2)	142
C10B—H10B···O2A^iv	0.98	2.29	3.171 (3)	150
C14B—H14E···O4A^v	0.96	2.49	3.423 (3)	163
C15B—H15D···O4A^v	0.96	2.46	3.405 (2)	166

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

Footnotes

‡Thomson Reuters ResearcherID: A-3561-2009.

§Additional correspondence author, e-mail: suchada.c@psu.ac.th. Thomson Reuters ResearcherID: A-5085-2009.

Acknowledgements

SL thanks the Thailand Research Fund (grant No. RSA5280011) for financial support. IS thanks Mae Fah Luang University for an MSc graduate student research grant. SC thanks the Prince of Songkla University for financial support through the Crystal Materials Research Unit (CMRU). The authors also thank Universiti Sains Malaysia for the Research University Grant No. 1001/PFIZIK/811160.

References

Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19. CrossRef Web of Science Google Scholar
Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105–107. CrossRef CAS Web of Science IUCr Journals Google Scholar
Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354–1358. CrossRef CAS Web of Science Google Scholar
Flack, H. D. (1983). Acta Cryst. A39, 876–881. CrossRef CAS Web of Science IUCr Journals Google Scholar
Ito, C., Itoigawa, M., Katsuno, S., Omura, M., Tokuda, H., Nishino, H. & Furukawa, H. (2000). J. Nat. Prod. 63, 1218–1224. Web of Science CrossRef PubMed CAS Google Scholar
Ito, C., Katsuno, S., Ohta, H., Omura, M., Kajirua, I. & Furukawa, H. (1997). Chem. Pharm. Bull. 45, 48–52. CrossRef CAS Google Scholar
Kamperdick, C., Phuong, N. M., Sun, T. V., Schmidt, J. & Adam, G. (1999). Phytochemistry, 52, 1671–1676. CrossRef CAS Google Scholar
Rahmani, M., Susidarti, R. A., Ismail, H. B. M., Sukari, M. A., Hin, T.-Y. Y., Lian, G. E. C., Ali, A. M., Kulip, J. & Waterman, P. G. (2003). Phytochemistry, 64, 873–877. Web of Science CrossRef PubMed CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
Tangyuenyongwatthana, P., Pummangura, S. & Thanyavuthi, D. (1992). Songklanakarin J. Sci. Technol. 14, 157–162. Google Scholar
Tantishaiyakul, V., Pummangura, S., Chaichantipyuth, C., Ma, W. W. & McLaughlin, J. L. (1986). J. Nat. Prod. 49, 180–181. CrossRef CAS PubMed Web of Science Google Scholar
Tantivatana, P., Ruana, G. M., Vaisiriroj, V., Lankin, D. C., Bhacca, M. C., Borris, R. P., Cordell, G. A. & Johnson, L. F. (1983). J. Org. Chem. 48, 268–270. CrossRef CAS Web of Science Google Scholar
Thuy, T. T., Ripperger, H., Porzel, A., Sung, T. V. & Adam, G. (1999). Phytochemistry, 52, 511–516. CrossRef CAS Google Scholar