Alternariol 9-O-methyl ether

Dasari, S.; Bhadbhade, M.; Neilan, B.A.

doi:10.1107/S1600536812015000

organic compounds

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ISSN: 2056-9890

Volume 68| Part 5| May 2012| Page o1471

doi:10.1107/S1600536812015000

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Alternariol 9-O-methyl ether

Sreekanth Dasari,^a Mohan Bhadbhade ^b and Brett A. Neilan ^a ^*

^aSchool of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, 2052 NSW, Australia, and ^bMark Wainwright Analytical Centre, University of New South Wales, Sydney, 2052 NSW, Australia
^*Correspondence e-mail: b.neilan@unsw.edu.au

(Received 3 April 2012; accepted 5 April 2012; online 21 April 2012)

The title compound (AME; systematic name: 3,7-dihydroxy-9-methoxy-1-methyl-6H-benzo[c]chromen-6-one), C₁₅H₁₂O₅, was isolated from an endophytic fungi Alternaria sp., from Catharanthus roseus (common name: Madagascar periwinkle). There is an intramolecular O—H⋯O hydrogen bond in the essentially planar molecule (r.m.s. deviation 0.02 Å). In the crystal, the molecule forms an O—H⋯O hydrogen bond with its centrosymmetric counterpart with four bridging interactions (two O—H⋯O and two C—H⋯O). The almost planar sheets of the dimeric units thus formed are stacked along b axis via C—H⋯π and π–π contacts [with C⋯C short contacts between aromatic moieties of 3.324 (3), 3.296 (3) and 3.374 (3) Å].

Related literature

Species of the fungal genus Alternaria are known producers of mycotoxins and have previously been described as plant endophytes. For the isolation of Alternariol (AOH) and Alternariol 9-O-methyl ether (AME) see: An et al. (1989 ); Wen (2009 ); Ashour et al. (2011 ). For ¹H, ¹³C and two-dimensional experimental data analysis see: Koch et al. (2005 ); Siegel et al. (2010 ). For the biological activity see: Aly et al. (2008 ).

Experimental

Crystal data

C₁₅H₁₂O₅
M_r = 272.25
Triclinic, $[P \overline 1]$
a = 7.1819 (7) Å
b = 8.9393 (8) Å
c = 10.2511 (10) Å
α = 105.296 (5)°
β = 105.174 (4)°
γ = 101.430 (4)°
V = 586.90 (10) Å³
Z = 2
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 160 K
0.29 × 0.13 × 0.06 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ) T_min = 0.967, T_max = 0.993
7824 measured reflections
2062 independent reflections
1718 reflections with I > 2σ(I)
R_int = 0.020

Refinement

R[F² > 2σ(F²)] = 0.033
wR(F²) = 0.096
S = 1.05
2062 reflections
184 parameters
H-atom parameters constrained
Δρ_max = 0.25 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
O4—H4⋯O4ⁱ	0.82	2.47	2.9371 (19)	117
C9—H9⋯O1ⁱⁱ	0.93	2.64	3.4645 (16)	148
C4—H4A⋯O2ⁱⁱⁱ	0.93	2.32	3.2511 (16)	174
O4—H4⋯O3	0.82	1.84	2.5692 (13)	148
O1—H1⋯O3ⁱⁱⁱ	0.82	2.14	2.9619 (13)	176
Symmetry codes: (i) -x+2, -y+1, -z+2; (ii) x, y+1, z+1; (iii) -x+2, -y, -z+1.

Data collection: APEX2 (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-Plus (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812015000/hg5207sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812015000/hg5207Isup2.hkl

checkCIF report

Comment top

The title compound was isolated from an endophytic Alternaria sp. from the host plant Catharanthus roseus. Alternariol 9-O-methyl ether is a mycotoxin often isolated from Alternaria sp.. It has been reported to exhibit mild antimicrobial activity (An et al., 1989; Wen 2009; Ashour et al., 2011), cytotoxicity and protein kinase inhibitory activity (Aly et al., 2008). ¹H, ¹³C and two-dimensional NMR spectral data was reported previously (Koch et al., 2005; Siegel et al., 2010). Although mycotoxins have been studied extensively, the single-crystal structure of alternariol 9-O-methy ether is reported here for the first time.

An ORTEP view of the title compound (Fig. 1) shows an intramolecular O4—H4···O3 hydrogen bond. The two centrosymmetric partners make a total of four interactions - the two hydrogen bonds O1—H1···O3⁽ⁱⁱⁱ⁾ and C4—H4A···O2⁽ⁱⁱⁱ⁾ , ((iii) -x + 2, -y, -z + 1) are duplicated across the inversion centre. The hydrogen H4 also makes a short contact with O4 of another centrosymmetrically related molecule (O4—H4···O4⁽ⁱ⁾, (i) -x + 2, -y + 1, -z + 2). The bridged centrosymmetric dimers translated along c axis make C9—H9···O1⁽ⁱⁱ⁾, (ii) x, y + 1, z + 1 and O4—H4···O4⁽ⁱ⁾ contacts (Table. 1 and Fig. 2). These almost planar sheets thus formed in ac plane are stacked along b axis; these make C—H···π contacts with the edge of the ring in one direction (C14—H14B···C9^(iv) = 2.88 Å and C15—H15C···C1^(iv) = 2.85 Å, (iv) 1 - x, 1 - y, 1 - z) and π–π contacts in the opposite direction with considerable overlap of aromatic moieties with values of short contact between C3···C8^(v) = 3.324 (3) Å, C1···C6^(v) = 3.296 (3) Å and C5···C12^(v) = 3.374 (3) Å with (v) 1 - x, -y, 1 - z (Fig. 3).

Related literature top

Species of the fungal genus Alternaria are known producers of mycotoxins and have previously been described as plant endophytes. For the isolation of Alternariol (AOH) and Alternariol 9-O-methyl ether (AME) see: An et al. (1989); Wen (2009); Ashour et al. (2011). For ¹H, ¹³C and two-dimensional experimental data analysis see: Koch et al. (2005); Siegel et al. (2010). For the biological activity see: Aly et al. (2008).

Experimental top

Alternaria sp. was isolated from Catharanthus roseus and cultured in malt extract media for production of secondary metabolites. The crude ethyl acetate extract was fractionated on silica gel with a stepwise gradient of hexane to ethyl acetate and to methanol to yield 12 fractions. Fractions 6 and 7, which were eluted with 2:1 and 1:1 hexane, ethyl acetate showed fine needle like crystals on slow evaporation. These fine needles were recrystallized using dichloromethane to yield plate like crystals for crystallographic analysis. The positive and negative ESI-MS analysis of the title compound exhibited molecular ion peak at m/z 273, attributing to [M+H]⁺ and at m/z 271, attributing to [M—H]^- , respectively, infereing its molecular weight to be 272 g/mol which is in agreement with the previously reported values (Ashour et al., 2011).

Computing details top

Data collection: APEX2 (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-Plus (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. ORTEP view of the title compound showing an intra molecular O—H···O hydrogen bond.. (Thermal ellipsoids are drawn at 40% probability level).
	Fig. 2. Molecular association forming planar sheets in ac plane via network of O—H···O and C—H···O contacts. Symmetry codes: (i) -x + 2, -y + 1, -z + 2; (ii) x, y + 1, z + 1; (iii) -x + 2, -y, -z + 1.
	Fig. 3. : Packing of molecules along b axis making C—H···π and π–π interactions. Symmetry codes: (iv) 1 - x, 1 - y, 1 - z; (v) 1 - x, -y, 1 - z.

3,7-dihydroxy-9-methoxy-1-methyl-6H-benzo[c]chromen-6-one top

Crystal data top

C₁₅H₁₂O₅	Z = 2
M_r = 272.25	F(000) = 284
Triclinic, P1	D_x = 1.541 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.1819 (7) Å	Cell parameters from 4112 reflections
b = 8.9393 (8) Å	θ = 2.7–29.6°
c = 10.2511 (10) Å	µ = 0.12 mm⁻¹
α = 105.296 (5)°	T = 160 K
β = 105.174 (4)°	Plates, colourless
γ = 101.430 (4)°	0.29 × 0.13 × 0.06 mm
V = 586.90 (10) Å³

Data collection top

Bruker Kappa APEXII CCD diffractometer	2062 independent reflections
Radiation source: fine-focus sealed tube	1718 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.020
ϕ scans, and ω scans with κ offsets	θ_max = 25.0°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −8→8
T_min = 0.967, T_max = 0.993	k = −10→10
7824 measured reflections	l = −12→12

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)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.096	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0511P)² + 0.1544P] where P = (F_o² + 2F_c²)/3
2062 reflections	(Δ/σ)_max < 0.001
184 parameters	Δρ_max = 0.25 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³

Crystal data top

C₁₅H₁₂O₅	γ = 101.430 (4)°
M_r = 272.25	V = 586.90 (10) Å³
Triclinic, P1	Z = 2
a = 7.1819 (7) Å	Mo Kα radiation
b = 8.9393 (8) Å	µ = 0.12 mm⁻¹
c = 10.2511 (10) Å	T = 160 K
α = 105.296 (5)°	0.29 × 0.13 × 0.06 mm
β = 105.174 (4)°

Data collection top

Bruker Kappa APEXII CCD diffractometer	2062 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2001)	1718 reflections with I > 2σ(I)
T_min = 0.967, T_max = 0.993	R_int = 0.020
7824 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.033	0 restraints
wR(F²) = 0.096	H-atom parameters constrained
S = 1.05	Δρ_max = 0.25 e Å⁻³
2062 reflections	Δρ_min = −0.20 e Å⁻³
184 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	0.65936 (15)	−0.18780 (12)	0.08182 (10)	0.0292 (3)
H1	0.7594	−0.2138	0.1163	0.044*
O2	0.84646 (14)	0.13308 (12)	0.56397 (9)	0.0245 (3)
O3	0.96545 (14)	0.26527 (12)	0.79381 (10)	0.0267 (3)
O4	0.78595 (15)	0.45323 (13)	0.91399 (10)	0.0329 (3)
H4	0.8735	0.4077	0.9083	0.049*
O5	0.17885 (16)	0.48775 (13)	0.61731 (11)	0.0331 (3)
C1	0.4041 (2)	0.07774 (16)	0.25561 (14)	0.0202 (3)
C2	0.4514 (2)	−0.03110 (16)	0.15399 (14)	0.0225 (3)
H2	0.3642	−0.0722	0.0598	0.027*
C3	0.6240 (2)	−0.08085 (16)	0.18775 (14)	0.0219 (3)
C4	0.7533 (2)	−0.02073 (16)	0.32735 (14)	0.0223 (3)
H4A	0.8701	−0.0517	0.3529	0.027*
C5	0.7053 (2)	0.08647 (16)	0.42815 (14)	0.0201 (3)
C6	0.8305 (2)	0.23648 (16)	0.67963 (14)	0.0208 (3)
C7	0.66319 (19)	0.30221 (15)	0.66141 (14)	0.0200 (3)
C8	0.6471 (2)	0.41025 (16)	0.78306 (14)	0.0232 (3)
C9	0.4878 (2)	0.47638 (16)	0.77364 (14)	0.0244 (3)
H9	0.4787	0.5483	0.8542	0.029*
C10	0.3421 (2)	0.43228 (16)	0.64067 (15)	0.0241 (3)
C11	0.3534 (2)	0.32476 (17)	0.51851 (14)	0.0249 (3)
H11	0.2522	0.2980	0.4311	0.030*
C12	0.5112 (2)	0.25710 (15)	0.52416 (14)	0.0197 (3)
C13	0.5353 (2)	0.14195 (16)	0.40140 (14)	0.0197 (3)
C14	0.2119 (2)	0.11934 (18)	0.20211 (14)	0.0267 (3)
H14A	0.1482	0.0608	0.1014	0.040*
H14B	0.2416	0.2335	0.2180	0.040*
H14C	0.1232	0.0903	0.2528	0.040*
C15	0.1611 (2)	0.60559 (18)	0.73528 (16)	0.0309 (4)
H15A	0.1602	0.5618	0.8112	0.046*
H15B	0.0380	0.6330	0.7045	0.046*
H15C	0.2733	0.7010	0.7693	0.046*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0335 (6)	0.0342 (6)	0.0220 (5)	0.0176 (5)	0.0108 (4)	0.0050 (4)
O2	0.0216 (5)	0.0295 (5)	0.0189 (5)	0.0119 (4)	0.0028 (4)	0.0029 (4)
O3	0.0210 (5)	0.0307 (6)	0.0217 (5)	0.0091 (4)	0.0008 (4)	0.0033 (4)
O4	0.0267 (6)	0.0418 (6)	0.0203 (5)	0.0153 (5)	0.0002 (4)	−0.0020 (4)
O5	0.0346 (6)	0.0396 (6)	0.0266 (5)	0.0252 (5)	0.0080 (4)	0.0050 (5)
C1	0.0205 (7)	0.0210 (7)	0.0199 (7)	0.0052 (5)	0.0071 (5)	0.0084 (5)
C2	0.0224 (7)	0.0254 (7)	0.0178 (7)	0.0049 (6)	0.0046 (5)	0.0075 (6)
C3	0.0261 (7)	0.0211 (7)	0.0211 (7)	0.0070 (6)	0.0121 (6)	0.0071 (6)
C4	0.0204 (7)	0.0251 (7)	0.0245 (7)	0.0100 (6)	0.0086 (6)	0.0095 (6)
C5	0.0188 (7)	0.0223 (7)	0.0180 (7)	0.0049 (5)	0.0045 (5)	0.0069 (5)
C6	0.0188 (7)	0.0203 (7)	0.0204 (7)	0.0032 (5)	0.0055 (6)	0.0046 (6)
C7	0.0185 (7)	0.0194 (7)	0.0212 (7)	0.0041 (5)	0.0060 (6)	0.0067 (6)
C8	0.0216 (7)	0.0227 (7)	0.0203 (7)	0.0033 (6)	0.0039 (6)	0.0044 (6)
C9	0.0278 (8)	0.0215 (7)	0.0228 (7)	0.0090 (6)	0.0098 (6)	0.0031 (6)
C10	0.0239 (7)	0.0238 (7)	0.0278 (7)	0.0112 (6)	0.0090 (6)	0.0102 (6)
C11	0.0259 (7)	0.0282 (8)	0.0188 (7)	0.0123 (6)	0.0037 (6)	0.0055 (6)
C12	0.0198 (7)	0.0187 (7)	0.0205 (7)	0.0045 (5)	0.0064 (5)	0.0075 (6)
C13	0.0197 (7)	0.0200 (7)	0.0202 (7)	0.0054 (5)	0.0069 (5)	0.0080 (6)
C14	0.0243 (8)	0.0326 (8)	0.0191 (7)	0.0106 (6)	0.0037 (6)	0.0040 (6)
C15	0.0335 (8)	0.0301 (8)	0.0333 (8)	0.0185 (7)	0.0152 (7)	0.0065 (7)

Geometric parameters (Å, º) top

O1—C3	1.3602 (16)	C5—C13	1.3958 (19)
O1—H1	0.8200	C6—C7	1.4299 (19)
O2—C6	1.3446 (16)	C7—C8	1.4090 (18)
O2—C5	1.3884 (15)	C7—C12	1.4338 (18)
O3—C6	1.2344 (16)	C8—C9	1.382 (2)
O4—C8	1.3486 (16)	C9—C10	1.3835 (19)
O4—H4	0.8200	C9—H9	0.9300
O5—C10	1.3508 (17)	C10—C11	1.3955 (19)
O5—C15	1.4317 (16)	C11—C12	1.3819 (19)
C1—C2	1.3889 (19)	C11—H11	0.9300
C1—C13	1.4305 (18)	C12—C13	1.4743 (18)
C1—C14	1.5031 (19)	C14—H14A	0.9600
C2—C3	1.3890 (19)	C14—H14B	0.9600
C2—H2	0.9300	C14—H14C	0.9600
C3—C4	1.3784 (18)	C15—H15A	0.9600
C4—C5	1.3785 (19)	C15—H15B	0.9600
C4—H4A	0.9300	C15—H15C	0.9600

C3—O1—H1	109.5	C8—C9—C10	117.96 (12)
C6—O2—C5	122.41 (10)	C8—C9—H9	121.0
C8—O4—H4	109.5	C10—C9—H9	121.0
C10—O5—C15	118.10 (11)	O5—C10—C9	123.74 (12)
C2—C1—C13	119.78 (12)	O5—C10—C11	114.42 (12)
C2—C1—C14	116.06 (11)	C9—C10—C11	121.84 (12)
C13—C1—C14	124.16 (12)	C12—C11—C10	121.63 (12)
C1—C2—C3	122.49 (12)	C12—C11—H11	119.2
C1—C2—H2	118.8	C10—C11—H11	119.2
C3—C2—H2	118.8	C11—C12—C7	116.99 (12)
O1—C3—C4	122.22 (12)	C11—C12—C13	125.49 (12)
O1—C3—C2	118.81 (12)	C7—C12—C13	117.51 (12)
C4—C3—C2	118.97 (12)	C5—C13—C1	114.81 (12)
C3—C4—C5	118.40 (12)	C5—C13—C12	117.24 (12)
C3—C4—H4A	120.8	C1—C13—C12	127.96 (12)
C5—C4—H4A	120.8	C1—C14—H14A	109.5
C4—C5—O2	111.77 (11)	C1—C14—H14B	109.5
C4—C5—C13	125.54 (12)	H14A—C14—H14B	109.5
O2—C5—C13	122.68 (12)	C1—C14—H14C	109.5
O3—C6—O2	115.38 (12)	H14A—C14—H14C	109.5
O3—C6—C7	125.97 (12)	H14B—C14—H14C	109.5
O2—C6—C7	118.65 (11)	O5—C15—H15A	109.5
C8—C7—C6	118.38 (11)	O5—C15—H15B	109.5
C8—C7—C12	120.11 (12)	H15A—C15—H15B	109.5
C6—C7—C12	121.49 (12)	O5—C15—H15C	109.5
O4—C8—C9	116.98 (12)	H15A—C15—H15C	109.5
O4—C8—C7	121.56 (12)	H15B—C15—H15C	109.5
C9—C8—C7	121.46 (12)

C13—C1—C2—C3	−0.4 (2)	C15—O5—C10—C11	−176.59 (12)
C14—C1—C2—C3	−179.96 (13)	C8—C9—C10—O5	179.73 (13)
C1—C2—C3—O1	−179.96 (12)	C8—C9—C10—C11	−0.1 (2)
C1—C2—C3—C4	0.3 (2)	O5—C10—C11—C12	179.96 (12)
O1—C3—C4—C5	−179.60 (12)	C9—C10—C11—C12	−0.2 (2)
C2—C3—C4—C5	0.2 (2)	C10—C11—C12—C7	0.1 (2)
C3—C4—C5—O2	178.48 (11)	C10—C11—C12—C13	179.58 (12)
C3—C4—C5—C13	−0.5 (2)	C8—C7—C12—C11	0.4 (2)
C6—O2—C5—C4	−179.66 (12)	C6—C7—C12—C11	178.63 (12)
C6—O2—C5—C13	−0.6 (2)	C8—C7—C12—C13	−179.21 (12)
C5—O2—C6—O3	179.01 (11)	C6—C7—C12—C13	−0.93 (19)
C5—O2—C6—C7	−0.80 (19)	C4—C5—C13—C1	0.4 (2)
O3—C6—C7—C8	0.1 (2)	O2—C5—C13—C1	−178.50 (11)
O2—C6—C7—C8	179.88 (12)	C4—C5—C13—C12	−179.87 (12)
O3—C6—C7—C12	−178.21 (13)	O2—C5—C13—C12	1.2 (2)
O2—C6—C7—C12	1.6 (2)	C2—C1—C13—C5	0.05 (19)
C6—C7—C8—O4	0.7 (2)	C14—C1—C13—C5	179.61 (12)
C12—C7—C8—O4	179.02 (12)	C2—C1—C13—C12	−179.65 (12)
C6—C7—C8—C9	−179.00 (13)	C14—C1—C13—C12	−0.1 (2)
C12—C7—C8—C9	−0.7 (2)	C11—C12—C13—C5	−179.96 (13)
O4—C8—C9—C10	−179.16 (12)	C7—C12—C13—C5	−0.44 (19)
C7—C8—C9—C10	0.5 (2)	C11—C12—C13—C1	−0.3 (2)
C15—O5—C10—C9	3.5 (2)	C7—C12—C13—C1	179.25 (12)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O4—H4···O4ⁱ	0.82	2.47	2.9371 (19)	117
C9—H9···O1ⁱⁱ	0.93	2.64	3.4645 (16)	148
C4—H4A···O2ⁱⁱⁱ	0.93	2.32	3.2511 (16)	174
O4—H4···O3	0.82	1.84	2.5692 (13)	148
O1—H1···O3ⁱⁱⁱ	0.82	2.14	2.9619 (13)	176

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

Experimental details

Crystal data
Chemical formula	C₁₅H₁₂O₅
M_r	272.25
Crystal system, space group	Triclinic, P1
Temperature (K)	160
a, b, c (Å)	7.1819 (7), 8.9393 (8), 10.2511 (10)
α, β, γ (°)	105.296 (5), 105.174 (4), 101.430 (4)
V (Å³)	586.90 (10)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.12
Crystal size (mm)	0.29 × 0.13 × 0.06

Data collection
Diffractometer	Bruker Kappa APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2001)
T_min, T_max	0.967, 0.993
No. of measured, independent and observed [I > 2σ(I)] reflections	7824, 2062, 1718
R_int	0.020
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.096, 1.05
No. of reflections	2062
No. of parameters	184
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.25, −0.20

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL-Plus (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O4—H4···O4ⁱ	0.82	2.47	2.9371 (19)	117.0
C9—H9···O1ⁱⁱ	0.93	2.64	3.4645 (16)	147.5
C4—H4A···O2ⁱⁱⁱ	0.93	2.32	3.2511 (16)	174.3
O4—H4···O3	0.82	1.84	2.5692 (13)	147.5
O1—H1···O3ⁱⁱⁱ	0.82	2.14	2.9619 (13)	175.7

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

Acknowledgements

This work was supported by the Australian Endeavour Fellowship Scheme (SD) and the Australian Research Council (BAN).

References

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