1,3-Dihydr­oxy-9,10-dioxo-9,10-di­hydro­anthracene-2-carbaldehyde

Awang, K.; Ismail, N.H.; Ahmad, R.; Saidan, N.H.; Retailleau, P.

doi:10.1107/S1600536808004169

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 64| Part 3| March 2008| Page o597

doi:10.1107/S1600536808004169

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1,3-Dihydroxy-9,10-dioxo-9,10-dihydroanthracene-2-carbaldehyde

Khalijah Awang,^a Nor Hadiani Ismail,^b Rohaya Ahmad,^b Nor Hafizoh Saidan ^b and Pascal Retailleau ^c ^*

^aChemistry Department, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia, ^bFaculty of Applied Sciences, Universiti Teknologi MARA Malaysia, 40450 Shah Alam, Selangor, Malaysia, and ^cICSN-CNRS, 1 avenue de la Terrasse, 91198 Gif sur Yvette, France
^*Correspondence e-mail: pascal.retailleau@icsn.cnrs-gif.fr

(Received 28 January 2008; accepted 11 February 2008; online 15 February 2008)

The title compound, C₁₅H₈O₅, also known as nordamnacanthal, was isolated from the Malaysian Morinda citrifolia L. The 20 non-H atoms are coplanar. The structure is stabilized by intramolecular O—H⋯O hydrogen bonds and intermolecular O—H⋯O and C—H⋯O hydrogen bonds, forming bilayers of molecular tapes with alternating stacking directions along the a axis.

Related literature

For related literature, see: Chan-Blanco et al. (2006 ); Ismail (1998 ); Ohsawa & Ohba (1993 ); Singh et al. (1984 ); Whistler (1985 ); Wijnsma & Verpoorte (1986 ); Zhu et al. (2008 ).

Experimental

Crystal data

C₁₅H₈O₅
M_r = 268.21
Monoclinic, P 2₁ /c
a = 10.547 (2) Å
b = 5.669 (1) Å
c = 20.231 (3) Å
β = 110.62 (4)°
V = 1132.1 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 293 (2) K
0.60 × 0.39 × 0.14 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: none
14030 measured reflections
2298 independent reflections
1554 reflections with I > 2σ(I)
R_int = 0.029

Refinement

R[F² > 2σ(F²)] = 0.051
wR(F²) = 0.150
S = 1.06
2296 reflections
181 parameters
H-atom parameters constrained
Δρ_max = 0.27 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3⋯O2	0.82	1.86	2.590 (3)	148
O1—H1⋯O5	0.82	1.86	2.577 (2)	146
O1—H1⋯O5ⁱ	0.82	2.34	2.933 (2)	130
C4—H4⋯O4ⁱⁱ	0.93	2.45	3.358 (2)	166
C10—H10⋯O2ⁱⁱⁱ	0.93	2.53	3.312 (3)	142
Symmetry codes: (i) -x, -y+1, -z; (ii) -x+1, -y+3, -z; (iii) $[x-1, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: DENZO (Otwinowski & Minor, 1997 ) and COLLECT (Nonius, 1999 ); cell refinement: DENZO and COLLECT; data reduction: SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR97 (Altomare et al., 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: PLATON (Spek, 2003 ) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: SHELXL97 and publCIF (Westrip, 2008 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808004169/bg2162sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808004169/bg2162Isup2.hkl

checkCIF report

Comment top

Morinda citrifolia Linn. (Noni), has been one of the most used traditional folk medicinal plants in Polynesia for over 2000 years (Whistler,1985). It has been reported to have a broad range of therapeutic and nutritional properties (Chan-Blanco et al.,2006) including antibacterial, antiviral, antifungal, antitumor, analgesic, hypotensive, anti-inflammatory and immune enhancing effects (Singh et al., 1984). Nordamnacanthal, damnacanthal and morindone (Ismail, 1998; Wijnsma & Verpoorte, 1986) have been isolated from the Malaysian Morinda citrifolia Linn. The crystal structure of damnacanthal having been reported by Ohsawa & Ohba (1993), we present in this communication the crystal structure of nordamnacanthal (I). (Fig. 1) shows its molecular structure. The C—C bond lengths in the anthraquinone ring range from 1.377 (3) Å to 1.484 (3) Å, the carbonyl bond distances from 1.220 (2) Å to 1.237 (2) Å and the two hydroxyl bond distances are 1.326 (2) Å and 1.349 (2) Å; all are comparable to those observed in similar structures (Ohsawa & Ohba, 1993; Zhu et al., 2008). All 20 non-H atoms of (I) are essentially coplanar, their mean deviation from the least-squares molecular plane being 0.028 Å and the dihedral angle between the two benzene rings being 1.27 (10)°. The molecule features two intramolecular O—H···O hydrogen bonds, with O3···O2 distance of 2.590 (3) Å and O1···O5 distance of 2.577 (2) Å. Additionally, atom O1 is also engaged into an intermolecular hydrogen bond with atom O5, viz. O1—H1···O5ⁱ [symmetry code:(i) -x, 1 - y, -z] leading to the formation of a coplanar centrosymmetric dimer via the key {H—O1—C1—C14—C13—O5}2 synthon, R₂²(12). Adjacent dimers extend through synthon R₂²(10) of weak C4—H4···O4ⁱⁱ [symmetry code:(ii) 1 - x, 3 - y, -z] hydrogen bond to form molecular tapes running parallel to the [120] and [120] directions (Fig. 2). The dihedral angle between the two molecular tape orientations is 66.03° and an additional weak C10—H10···O4ⁱⁱⁱ [symmetry code:(ii) -1 + x, 3/2 - y, -1/2 + z] hydrogen bond links the tapes along the c axis. The tapes are stacked along the a axis, forming two kinds of layers in which molecules related by an inversion center stack with an interplanar spacing of 3.255 (4) Å and a centroid offset of ca 3.5 Å (Fig. 3).

Related literature top

For related literature, see: Chan-Blanco et al. (2006); Ismail (1998); Ohsawa & Ohba (1993); Singh et al. (1984); Whistler (1985); Wijnsma & Verpoorte (1986); Zhu et al. (2008).

Experimental top

Morinda citrifolia used in this study was collected from kg. Tanjung Keramat, Langkap, Perak. The roots were harvested, washed, chopped into small pieces and then dried at room temperature for one week. The dried sample was then ground to small size using grinder. The ground roots (1.5 kg) were soaked at room temperature in dichloromethane for 48 h. The solvent was then removed by filtration and fresh solvent added to the plant material. The extraction was repeated three times. The combined filtrate was evaporated under reduced pressure to give brown coloured residue (35.6 g). The crude extract was fractionated using Medium Pressure Liquid Chromatography (MPLC) system fitted with Buchi Pump Module C-601. The sample (10 g) was introduced dry after being pre-absorbed onto acid-washed silica gel (10 g) in two portions. The column (150 mm x 40 mm) was packed with 90 g acid-washed silica gel (Merck 7734) and eluted gradiently with petroleum ether, chloroform and chloroform enriched with increasing percentages of methanol (1%, 2% and 5%). Seven combined fractions were collected based on thin layer chromatography (TLC) pattern (labeled A, B, C, D, E, F, and G).

Nordamnacanthal (1.65 g) were isolated from fraction A after column chromatography. The fraction was re-chromatographed using small column (400 mm x 20 mm) packed with 2% acid-washed silica gel (Merck 9385) eluted gradiently with petroleum ether and chloroform. The first orange band eluted out from the column was collected in small vials and inspected using analytical TLC developed in PE:CHCl3 (4:6) showing a single spot of a purified compound. Recrystallization from hot CHCl3 gave bright orange crystals.

Computing details top

Data collection: DENZO (Otwinowski & Minor, 1997) and COLLECT (Nonius, 1999); cell refinement: DENZO (Otwinowski & Minor, 1997) and COLLECT (Nonius, 1999); data reduction: SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2003) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and publCIF (Westrip, 2008).

Figures top

	Fig. 1. Perspective view of the title compound with the atom numbering; displacement ellipsoids are at the 50% probability level. The intramolecular O—H···O interactions are shown as dotted lines.
	Fig. 2. Part of the crystal structure showing non-parallel molecular slabs forming herringbone pattern along a. (Intra-)Inter-molecular hydrogen bonds are indicated by (dotted) dashed lines. Symmetry codes: as in Table 1.
	Fig. 3. The crystal packing showing the two orientations taken by the stacking of molecular tapes. Note the offset between successive layers.

1,3-Dihydroxy-9,10-dioxo-9,10-dihydroanthracene-2-carbaldehyde top

Crystal data top

C₁₅H₈O₅	F(000) = 552
M_r = 268.21	D_x = 1.574 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71070 Å
Hall symbol: -P 2ybc	Cell parameters from 10451 reflections
a = 10.547 (2) Å	θ = 0.4–26.4°
b = 5.669 (1) Å	µ = 0.12 mm⁻¹
c = 20.231 (3) Å	T = 293 K
β = 110.62 (4)°	Prism, orange
V = 1132.1 (5) Å³	0.60 × 0.39 × 0.14 mm
Z = 4

Data collection top

Nonius KappaCCD diffractometer	1554 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.029
Graphite monochromator	θ_max = 26.4°, θ_min = 2.1°
ϕ and ω scans	h = 0→13
14030 measured reflections	k = −7→0
2298 independent reflections	l = −25→22

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.051	Hydrogen site location: difference Fourier map
wR(F²) = 0.150	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.0705P)² + 0.3487P] where P = (F_o² + 2F_c²)/3
2296 reflections	(Δ/σ)_max < 0.001
181 parameters	Δρ_max = 0.27 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³

Crystal data top

C₁₅H₈O₅	V = 1132.1 (5) Å³
M_r = 268.21	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 10.547 (2) Å	µ = 0.12 mm⁻¹
b = 5.669 (1) Å	T = 293 K
c = 20.231 (3) Å	0.60 × 0.39 × 0.14 mm
β = 110.62 (4)°

Data collection top

Nonius KappaCCD diffractometer	1554 reflections with I > 2σ(I)
14030 measured reflections	R_int = 0.029
2298 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.051	0 restraints
wR(F²) = 0.150	H-atom parameters constrained
S = 1.06	Δρ_max = 0.27 e Å⁻³
2296 reflections	Δρ_min = −0.20 e Å⁻³
181 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 (2298) except two reflections with Delta(F²)/e.s.d. greater than 9 (2296). 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
O4	0.32777 (16)	1.4401 (3)	−0.05914 (8)	0.0669 (5)
O5	0.02849 (14)	0.7077 (2)	−0.03142 (7)	0.0531 (4)
O1	0.22406 (15)	0.5649 (2)	0.07880 (7)	0.0525 (4)
H1	0.1487	0.5610	0.0479	0.063*
O3	0.62014 (15)	1.0321 (3)	0.15870 (9)	0.0746 (5)
H3	0.6408	0.9283	0.1889	0.090*
O2	0.58762 (18)	0.6610 (3)	0.22568 (9)	0.0811 (6)
C6	0.2604 (2)	1.2727 (3)	−0.05264 (10)	0.0437 (5)
C7	0.12238 (19)	1.2323 (3)	−0.10446 (9)	0.0388 (5)
C12	0.04523 (18)	1.0390 (3)	−0.09796 (9)	0.0364 (4)
C13	0.09986 (19)	0.8728 (3)	−0.03790 (10)	0.0388 (5)
C14	0.23549 (18)	0.9106 (3)	0.01290 (10)	0.0377 (4)
C5	0.31419 (18)	1.1053 (3)	0.00715 (10)	0.0396 (5)
C4	0.4429 (2)	1.1451 (4)	0.05601 (11)	0.0493 (5)
H4	0.4935	1.2742	0.0513	0.059*
C3	0.4949 (2)	0.9898 (4)	0.11180 (11)	0.0521 (6)
C2	0.4211 (2)	0.7925 (4)	0.11979 (10)	0.0461 (5)
C1	0.2905 (2)	0.7533 (3)	0.06963 (10)	0.0425 (5)
C15	0.4762 (3)	0.6333 (4)	0.17886 (13)	0.0652 (7)
H15	0.4247	0.5031	0.1817	0.078*
C11	−0.0846 (2)	1.0056 (4)	−0.14710 (10)	0.0446 (5)
H11	−0.1359	0.8766	−0.1430	0.054*
C10	−0.1371 (2)	1.1638 (4)	−0.20178 (10)	0.0509 (5)
H10	−0.2239	1.1414	−0.2346	0.061*
C9	−0.0613 (2)	1.3547 (4)	−0.20791 (11)	0.0539 (6)
H9	−0.0975	1.4613	−0.2447	0.065*
C8	0.0679 (2)	1.3894 (4)	−0.15996 (10)	0.0486 (5)
H8	0.1185	1.5183	−0.1648	0.058*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O4	0.0621 (10)	0.0626 (10)	0.0708 (11)	−0.0288 (8)	0.0169 (8)	0.0066 (8)
O5	0.0512 (9)	0.0466 (8)	0.0591 (9)	−0.0150 (7)	0.0163 (7)	0.0068 (7)
O1	0.0511 (9)	0.0471 (8)	0.0565 (9)	−0.0020 (7)	0.0155 (7)	0.0087 (7)
O3	0.0437 (9)	0.0866 (12)	0.0726 (11)	−0.0075 (8)	−0.0056 (8)	−0.0060 (9)
O2	0.0657 (11)	0.0934 (13)	0.0606 (11)	0.0183 (10)	−0.0071 (9)	0.0054 (9)
C6	0.0458 (11)	0.0411 (11)	0.0474 (11)	−0.0107 (9)	0.0201 (9)	−0.0052 (9)
C7	0.0434 (11)	0.0367 (10)	0.0381 (10)	−0.0049 (8)	0.0167 (9)	−0.0044 (8)
C12	0.0367 (10)	0.0360 (10)	0.0374 (10)	−0.0028 (8)	0.0142 (8)	−0.0048 (8)
C13	0.0419 (11)	0.0355 (10)	0.0421 (11)	−0.0054 (8)	0.0187 (9)	−0.0036 (8)
C14	0.0370 (10)	0.0388 (10)	0.0378 (10)	0.0018 (8)	0.0138 (8)	−0.0027 (8)
C5	0.0359 (10)	0.0413 (10)	0.0426 (11)	−0.0048 (8)	0.0152 (8)	−0.0075 (8)
C4	0.0450 (12)	0.0496 (12)	0.0536 (13)	−0.0085 (9)	0.0176 (10)	−0.0075 (10)
C3	0.0386 (11)	0.0605 (13)	0.0511 (13)	0.0012 (10)	0.0081 (10)	−0.0113 (11)
C2	0.0427 (11)	0.0504 (12)	0.0423 (11)	0.0075 (9)	0.0112 (9)	−0.0026 (9)
C1	0.0432 (11)	0.0404 (11)	0.0474 (11)	0.0016 (8)	0.0202 (9)	−0.0033 (8)
C15	0.0664 (15)	0.0655 (15)	0.0561 (14)	0.0136 (12)	0.0122 (12)	0.0028 (12)
C11	0.0413 (11)	0.0467 (11)	0.0457 (11)	−0.0068 (9)	0.0149 (9)	−0.0065 (9)
C10	0.0433 (11)	0.0603 (13)	0.0430 (11)	0.0026 (10)	0.0075 (9)	−0.0059 (10)
C9	0.0634 (14)	0.0528 (13)	0.0422 (12)	0.0073 (11)	0.0146 (11)	0.0072 (9)
C8	0.0578 (13)	0.0430 (11)	0.0471 (12)	−0.0066 (9)	0.0209 (11)	0.0014 (9)

Geometric parameters (Å, º) top

O4—C6	1.220 (2)	C14—C5	1.410 (3)
O5—C13	1.237 (2)	C5—C4	1.388 (3)
O1—C1	1.326 (2)	C4—C3	1.383 (3)
O1—H1	0.8200	C4—H4	0.9300
O3—C3	1.349 (3)	C3—C2	1.404 (3)
O3—H3	0.8200	C2—C1	1.411 (3)
O2—C15	1.233 (3)	C2—C15	1.446 (3)
C6—C7	1.482 (3)	C15—H15	0.9300
C6—C5	1.484 (3)	C11—C10	1.380 (3)
C7—C8	1.389 (3)	C11—H11	0.9300
C7—C12	1.399 (2)	C10—C9	1.377 (3)
C12—C11	1.393 (3)	C10—H10	0.9300
C12—C13	1.484 (3)	C9—C8	1.380 (3)
C13—C14	1.454 (3)	C9—H9	0.9300
C14—C1	1.407 (3)	C8—H8	0.9300

C1—O1—H1	109.5	O3—C3—C2	120.4 (2)
C3—O3—H3	109.5	C4—C3—C2	121.61 (18)
O4—C6—C7	120.56 (18)	C3—C2—C1	118.88 (18)
O4—C6—C5	121.01 (18)	C3—C2—C15	121.0 (2)
C7—C6—C5	118.43 (16)	C1—C2—C15	120.1 (2)
C8—C7—C12	119.32 (18)	O1—C1—C14	122.54 (18)
C8—C7—C6	119.77 (17)	O1—C1—C2	117.17 (18)
C12—C7—C6	120.91 (17)	C14—C1—C2	120.29 (18)
C11—C12—C7	119.84 (17)	O2—C15—C2	123.5 (3)
C11—C12—C13	119.92 (16)	O2—C15—H15	118.2
C7—C12—C13	120.23 (16)	C2—C15—H15	118.2
O5—C13—C14	121.38 (17)	C10—C11—C12	120.01 (19)
O5—C13—C12	119.46 (17)	C10—C11—H11	120.0
C14—C13—C12	119.15 (16)	C12—C11—H11	120.0
C1—C14—C5	118.53 (17)	C9—C10—C11	120.08 (19)
C1—C14—C13	120.26 (17)	C9—C10—H10	120.0
C5—C14—C13	121.21 (17)	C11—C10—H10	120.0
C4—C5—C14	121.66 (18)	C10—C9—C8	120.6 (2)
C4—C5—C6	118.30 (17)	C10—C9—H9	119.7
C14—C5—C6	120.04 (17)	C8—C9—H9	119.7
C3—C4—C5	119.03 (19)	C9—C8—C7	120.12 (19)
C3—C4—H4	120.5	C9—C8—H8	119.9
C5—C4—H4	120.5	C7—C8—H8	119.9
O3—C3—C4	118.0 (2)

O4—C6—C7—C8	−1.6 (3)	C6—C5—C4—C3	−179.58 (18)
C5—C6—C7—C8	178.31 (17)	C5—C4—C3—O3	−179.91 (17)
O4—C6—C7—C12	179.08 (18)	C5—C4—C3—C2	0.5 (3)
C5—C6—C7—C12	−1.0 (3)	O3—C3—C2—C1	−179.82 (18)
C8—C7—C12—C11	0.3 (3)	C4—C3—C2—C1	−0.3 (3)
C6—C7—C12—C11	179.58 (17)	O3—C3—C2—C15	1.2 (3)
C8—C7—C12—C13	−178.19 (17)	C4—C3—C2—C15	−179.25 (19)
C6—C7—C12—C13	1.1 (3)	C5—C14—C1—O1	−179.51 (17)
C11—C12—C13—O5	−1.1 (3)	C13—C14—C1—O1	1.1 (3)
C7—C12—C13—O5	177.34 (17)	C5—C14—C1—C2	0.7 (3)
C11—C12—C13—C14	−179.93 (16)	C13—C14—C1—C2	−178.70 (17)
C7—C12—C13—C14	−1.5 (3)	C3—C2—C1—O1	179.83 (17)
O5—C13—C14—C1	2.3 (3)	C15—C2—C1—O1	−1.2 (3)
C12—C13—C14—C1	−178.89 (16)	C3—C2—C1—C14	−0.3 (3)
O5—C13—C14—C5	−177.04 (18)	C15—C2—C1—C14	178.65 (18)
C12—C13—C14—C5	1.8 (3)	C3—C2—C15—O2	1.2 (4)
C1—C14—C5—C4	−0.4 (3)	C1—C2—C15—O2	−177.7 (2)
C13—C14—C5—C4	178.95 (17)	C7—C12—C11—C10	−0.4 (3)
C1—C14—C5—C6	178.98 (16)	C13—C12—C11—C10	178.07 (17)
C13—C14—C5—C6	−1.7 (3)	C12—C11—C10—C9	0.0 (3)
O4—C6—C5—C4	0.6 (3)	C11—C10—C9—C8	0.4 (3)
C7—C6—C5—C4	−179.34 (17)	C10—C9—C8—C7	−0.5 (3)
O4—C6—C5—C14	−178.84 (19)	C12—C7—C8—C9	0.2 (3)
C7—C6—C5—C14	1.3 (3)	C6—C7—C8—C9	−179.14 (18)
C14—C5—C4—C3	−0.2 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O2	0.82	1.86	2.590 (3)	148
O1—H1···O5	0.82	1.86	2.577 (2)	146
O1—H1···O5ⁱ	0.82	2.34	2.933 (2)	130
C4—H4···O4ⁱⁱ	0.93	2.45	3.358 (2)	166
C10—H10···O2ⁱⁱⁱ	0.93	2.53	3.312 (3)	142

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

Experimental details

Crystal data
Chemical formula	C₁₅H₈O₅
M_r	268.21
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	10.547 (2), 5.669 (1), 20.231 (3)
β (°)	110.62 (4)
V (Å³)	1132.1 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.12
Crystal size (mm)	0.60 × 0.39 × 0.14

Data collection
Diffractometer	Nonius KappaCCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	14030, 2298, 1554
R_int	0.029
(sin θ/λ)_max (Å⁻¹)	0.626

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.051, 0.150, 1.06
No. of reflections	2296
No. of parameters	181
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.27, −0.20

Computer programs: DENZO (Otwinowski & Minor, 1997) and COLLECT (Nonius, 1999), SCALEPACK (Otwinowski & Minor, 1997), SIR97 (Altomare et al., 1999), PLATON (Spek, 2003) and Mercury (Macrae et al., 2006), SHELXL97 (Sheldrick, 2008) and publCIF (Westrip, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O2	0.82	1.86	2.590 (3)	147.6
O1—H1···O5	0.82	1.86	2.577 (2)	146.2
O1—H1···O5ⁱ	0.82	2.34	2.933 (2)	129.5
C4—H4···O4ⁱⁱ	0.93	2.45	3.358 (2)	166.0
C10—H10···O2ⁱⁱⁱ	0.93	2.53	3.312 (3)	141.6

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

Acknowledgements

KA thanks the Universiti Teknologi MARA and the Ministry of Science and Technology for financial support, and the Institut de Chimie des Substances Naturelles for research facilities.

References

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