Desoxyhemigossypol 6-methyl ether

Uzbekov, V.V.; Talipov, S.A.; Ibragimov, B.T.; Stipanovic, R.D.; Liu, J.

doi:10.1107/S1600536813002304

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 69| Part 2| February 2013| Page o302

doi:10.1107/S1600536813002304

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Desoxyhemigossypol 6-methyl ether

Vyacheslav V. Uzbekov,^a ^* Samat A. Talipov,^a Bakhtiyar T. Ibragimov,^a Robert D. Stipanovic ^b and Jinggao Liu ^b

^aInstitute of Bioorganic Chemistry, Academy of Sciences of Uzbekistan, M. Ulugbek str. 83, Tashkent, 100125 Uzbekistan, and ^bSouthern Plains Agricultural Research Center, Agricultural Research, Service, USDA, College Station, TX 77845, USA
^*Correspondence e-mail: via74@yandex.ru

(Received 24 October 2012; accepted 23 January 2013; online 31 January 2013)

The title sesquiterpene [systematic name: 6-methoxy-10-methyl-7-(propan-2-yl)-2-oxatricyclo[6.3.1.0^4,12]dodeca-1(11),4,6,8(12),9-pentaen-5-ol], C₁₆H₁₈O₃, was isolated from pathogen-infected stele tissue of Gossypium barbadense. There are two molecules in the asymmetric unit and the dihedral angle between their naphthofuran systems is 86.48 (2)°. In the crystal, O—H⋯O hydrogen bonds between the hydroxy groups and etheric O atoms link the molecules into centrosymmetric tetramers. These tetramers are assembled into (010) layers via stacking interactions between the naphthofuran systems [interplanar distance 3.473 (3) Å] and short C—H⋯O contacts.

Related literature

For the isolation and chemical structure determination of related cotton sesquiterpenoid phytoalexins and their intermediates, see: Bell et al. (1975 ); Stipanovic et al. (1975 ). For the role of terpenoid aldehydes as phytoalexins (active defense agents) in response to infection by wilt fungi, see: Mace (1978 ). For information on the mechanism of action, see: Mace et al. (1995 ). For the mechanism of O-methylation of desoxyhemigossypol, see: Liu et al. (2002 ). For general information about antimicrobial compounds produced by cotton, see: Bell (1995 ).

Experimental

Crystal data

C₁₆H₁₈O₃
M_r = 258.30
Triclinic, $[P \overline 1]$
a = 10.0275 (5) Å
b = 11.1058 (6) Å
c = 13.2938 (8) Å
α = 107.797 (5)°
β = 103.896 (5)°
γ = 90.435 (4)°
V = 1363.08 (13) Å³
Z = 4
Cu Kα radiation
μ = 0.69 mm⁻¹
T = 293 K
0.40 × 0.34 × 0.28 mm

Data collection

Oxford Diffraction Xcalibur Ruby diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]$ ) T_min = 0.925, T_max = 1.000
10119 measured reflections
5476 independent reflections
3775 reflections with I > 2σ(I)
R_int = 0.027

Refinement

R[F² > 2σ(F²)] = 0.050
wR(F²) = 0.158
S = 1.04
5476 reflections
354 parameters
H-atom parameters constrained
Δρ_max = 0.45 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2A⋯O3	0.82	2.28	2.723 (2)	114
O2—H2A⋯O4ⁱ	0.82	2.11	2.809 (2)	144
O5—H5⋯O3	0.82	2.13	2.7843 (19)	137
O5—H5⋯O6	0.82	2.27	2.719 (2)	115
C12—H12B⋯O2ⁱⁱ	0.97	2.48	3.445 (3)	171
Symmetry codes: (i) -x+2, -y+1, -z; (ii) -x+2, -y+1, -z+1.

Data collection: CrysAlis PRO (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]$ ); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536813002304/gk2530sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813002304/gk2530Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813002304/gk2530Isup3.cml

checkCIF report

Comment top

The title sesquiterpene compound with systematic name 3-hydroxy-5-(1-methylethyl)-4-methoxy-7-methyl-2H-naphtho[1,8-bc]furan, was isolated from pathogen-infected stele tissue of Gossypium barbadense (fine-fibre Egyptian cotton) where it plays a role as a phytoalexin (active defense agent in response to infection by wilt fungi). The plant is widely cultivated in cotton-producing countries such as USA, Mexico, China, Uzbekistan and Egypt. Here we report its crystal structure.

The numbering scheme of atoms is shown in Fig. 1. The 12 non-hydrogen atoms of the naphthofuran system in each of the two symmetry independent molecules are virtually coplanar with r.m.s. values of 0.020 and 0.028 Å. Hydrogen bonds between hydroxy group and etheric oxygen atom link the molecules into centrosymmetric tertramers (Table 1, Fig. 2). These tertramers are assembled into (010) layers via stacking interactions between the naphthofuran systems [interplanar distance 3.473 (3) Å] and short C—H···O interactions.

Related literature top

For the isolation and chemical structure determination of related cotton sesquiterpenoid phytoalexins and their intermediates, see: Bell et al. (1975); Stipanovic et al. (1975). For the role of terpenoid aldehydes as phytoalexins (active defense agents) in response to infection by wilt fungi, see: Mace (1978). For information on the mechanism of action, see: Mace et al. (1995). For the mechanism of O-methylation of desoxyhemigossypol, see: Liu et al. (2002). For general information about antimicrobial compounds produced by cotton, see: Bell (1995).

Experimental top

The title compound was extracted from V. dahliae infected cotton stems and the crude extract, was purified by column and TLC chromatography as described by Bell et al.(1975), and crystalized from CHCl₃ and hexane to give crystals (m.p. 429-433 K). These crystals were further purified by semi-preparative reverse phase HPLC (Agilent 1100 HPLC system; Zorbax Eclipse XDB C8 column; Agilent Technologies Inc., USA) with dimensions 9.4 × 250 mm and particle size 5 µm. The column was eluted using a linear gradient of H₂O(A)/CH₃CN(B) [LC grade, Sigma-Aldrich, DE], both with 0.01% ortho-phosphoric acid pH 2.5 (from 55 to 95% B for 20 minutes) at a flow rate of 4 ml/min. Crystals suitable for X-ray diffraction analysis were obtained by slow evaporation of the HPLC eluent.

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of title compound with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. Hydrogen bonded tetramer of the title compound. Atoms with the A label are generated by the symmetry operation 2-x, 1-y, -z.
	Fig. 3. A packing diagram for the title compound. Short contacts are represented by dashed lines.

6-Methoxy-10-methyl-7-(propan-2-yl)-2-oxatricyclo[6.3.1.0^4,12]dodeca-1(11),4,6,8(12),9-pentaen-5-ol top

Crystal data top

C₁₆H₁₈O₃	Z = 4
M_r = 258.30	F(000) = 552
Triclinic, P1	D_x = 1.259 Mg m⁻³
Hall symbol: -P 1	Cu Kα radiation, λ = 1.54184 Å
a = 10.0275 (5) Å	Cell parameters from 3316 reflections
b = 11.1058 (6) Å	θ = 3.6–75.7°
c = 13.2938 (8) Å	µ = 0.69 mm⁻¹
α = 107.797 (5)°	T = 293 K
β = 103.896 (5)°	Block, colourless
γ = 90.435 (4)°	0.40 × 0.34 × 0.28 mm
V = 1363.08 (13) Å³

Data collection top

Oxford Diffraction Xcalibur Ruby diffractometer	5476 independent reflections
Radiation source: fine-focus sealed tube	3775 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.027
Detector resolution: 10.2576 pixels mm^-1	θ_max = 75.9°, θ_min = 3.6°
ω scans	h = −11→12
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	k = −13→12
T_min = 0.925, T_max = 1.000	l = −16→16
10119 measured reflections

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)] = 0.050	H-atom parameters constrained
wR(F²) = 0.158	w = 1/[σ²(F_o²) + (0.0881P)² + 0.0965P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max < 0.001
5476 reflections	Δρ_max = 0.45 e Å⁻³
354 parameters	Δρ_min = −0.22 e Å⁻³
0 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0038 (6)

Crystal data top

C₁₆H₁₈O₃	γ = 90.435 (4)°
M_r = 258.30	V = 1363.08 (13) Å³
Triclinic, P1	Z = 4
a = 10.0275 (5) Å	Cu Kα radiation
b = 11.1058 (6) Å	µ = 0.69 mm⁻¹
c = 13.2938 (8) Å	T = 293 K
α = 107.797 (5)°	0.40 × 0.34 × 0.28 mm
β = 103.896 (5)°

Data collection top

Oxford Diffraction Xcalibur Ruby diffractometer	5476 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	3775 reflections with I > 2σ(I)
T_min = 0.925, T_max = 1.000	R_int = 0.027
10119 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.050	0 restraints
wR(F²) = 0.158	H-atom parameters constrained
S = 1.04	Δρ_max = 0.45 e Å⁻³
5476 reflections	Δρ_min = −0.22 e Å⁻³
354 parameters

Special details top

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 > 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
C1	0.6372 (2)	0.6300 (2)	0.60266 (16)	0.0584 (5)
C2	0.5457 (3)	0.7031 (2)	0.64751 (18)	0.0701 (7)
H2	0.5440	0.7154	0.7196	0.084*
C3	0.4517 (3)	0.7608 (2)	0.5804 (2)	0.0673 (6)
C4	0.4535 (2)	0.7425 (2)	0.47364 (18)	0.0583 (5)
H4	0.3927	0.7831	0.4328	0.070*
C5	0.56004 (19)	0.62981 (17)	0.31437 (15)	0.0461 (4)
C6	0.65818 (18)	0.54699 (17)	0.28745 (14)	0.0448 (4)
C7	0.74826 (19)	0.49542 (18)	0.36144 (16)	0.0479 (4)
C8	0.73732 (19)	0.52956 (19)	0.46605 (16)	0.0492 (4)
C9	0.63691 (19)	0.61040 (18)	0.49337 (15)	0.0487 (4)
C10	0.54617 (19)	0.66320 (18)	0.42417 (15)	0.0486 (4)
C11	0.3488 (3)	0.8409 (3)	0.6302 (3)	0.0941 (9)
H11A	0.3084	0.8905	0.5848	0.141*
H11B	0.3947	0.8965	0.7016	0.141*
H11C	0.2777	0.7868	0.6359	0.141*
C12	0.8076 (2)	0.4986 (2)	0.56747 (18)	0.0641 (6)
H12A	0.7977	0.4079	0.5551	0.077*
H12B	0.9050	0.5272	0.5900	0.077*
C13	0.4747 (2)	0.6820 (2)	0.22867 (18)	0.0594 (5)
H13	0.5046	0.6427	0.1619	0.071*
C14	0.3207 (2)	0.6418 (3)	0.1997 (2)	0.0762 (7)
H14A	0.3072	0.5517	0.1843	0.114*
H14B	0.2747	0.6640	0.1365	0.114*
H14C	0.2835	0.6845	0.2600	0.114*
C15	0.5064 (3)	0.8232 (2)	0.2559 (3)	0.0853 (8)
H15A	0.4851	0.8668	0.3238	0.128*
H15B	0.4517	0.8515	0.1989	0.128*
H15C	0.6024	0.8411	0.2623	0.128*
C16	0.5963 (2)	0.4046 (2)	0.10614 (18)	0.0665 (6)
H16A	0.6233	0.3830	0.0387	0.100*
H16B	0.5017	0.4238	0.0935	0.100*
H16C	0.6065	0.3342	0.1342	0.100*
O1	0.73758 (17)	0.56665 (17)	0.64974 (12)	0.0721 (5)
O2	0.84360 (15)	0.41512 (15)	0.33045 (13)	0.0626 (4)
H2A	0.8335	0.3970	0.2643	0.094*
O3	0.68208 (14)	0.51333 (13)	0.18394 (10)	0.0530 (3)
C17	1.1325 (2)	0.81302 (19)	−0.05314 (15)	0.0498 (4)
C18	1.2223 (2)	0.9049 (2)	−0.05337 (17)	0.0561 (5)
H18	1.2599	0.8966	−0.1124	0.067*
C19	1.2561 (2)	1.0143 (2)	0.04066 (18)	0.0555 (5)
C20	1.2035 (2)	1.02680 (19)	0.12981 (17)	0.0530 (5)
H20	1.2300	1.0994	0.1903	0.064*
C21	1.04433 (19)	0.92410 (18)	0.21481 (16)	0.0480 (4)
C22	0.9539 (2)	0.81841 (18)	0.19220 (15)	0.0485 (4)
C23	0.9187 (2)	0.71749 (18)	0.09065 (15)	0.0490 (4)
C24	0.9836 (2)	0.72145 (17)	0.01286 (15)	0.0480 (4)
C25	1.07617 (18)	0.82592 (17)	0.03528 (15)	0.0452 (4)
C26	1.10907 (18)	0.93059 (17)	0.13117 (15)	0.0456 (4)
C27	1.3522 (3)	1.1198 (2)	0.0407 (2)	0.0745 (7)
H27A	1.3271	1.2002	0.0809	0.112*
H27B	1.3452	1.1177	−0.0332	0.112*
H27C	1.4453	1.1088	0.0743	0.112*
C28	0.9801 (2)	0.6354 (2)	−0.09991 (17)	0.0599 (5)
H28A	1.0057	0.5518	−0.0983	0.072*
H28B	0.8891	0.6269	−0.1488	0.072*
C29	1.0730 (2)	1.0259 (2)	0.32693 (17)	0.0585 (5)
H29	1.0156	0.9971	0.3667	0.070*
C30	1.2201 (2)	1.0329 (2)	0.39328 (19)	0.0680 (6)
H30A	1.2413	0.9502	0.3977	0.102*
H30B	1.2305	1.0910	0.4655	0.102*
H30C	1.2818	1.0619	0.3587	0.102*
C31	1.0288 (3)	1.1533 (2)	0.3244 (2)	0.0766 (7)
H31A	1.0832	1.1876	0.2876	0.115*
H31B	1.0417	1.2091	0.3978	0.115*
H31C	0.9332	1.1450	0.2863	0.115*
C32	0.9621 (3)	0.7427 (3)	0.3406 (2)	0.0781 (7)
H32A	0.9789	0.6596	0.2989	0.117*
H32B	0.9104	0.7354	0.3908	0.117*
H32C	1.0485	0.7914	0.3804	0.117*
O4	1.08204 (16)	0.69916 (14)	−0.13428 (11)	0.0607 (4)
O5	0.82418 (17)	0.61951 (15)	0.07111 (12)	0.0663 (4)
H5	0.7976	0.6270	0.1263	0.099*
O6	0.88542 (15)	0.80485 (15)	0.26829 (12)	0.0612 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0624 (13)	0.0646 (13)	0.0392 (10)	−0.0247 (10)	0.0058 (9)	0.0100 (9)
C2	0.0794 (16)	0.0761 (15)	0.0450 (11)	−0.0301 (12)	0.0200 (11)	0.0029 (10)
C3	0.0718 (14)	0.0577 (13)	0.0658 (14)	−0.0165 (10)	0.0293 (12)	0.0015 (11)
C4	0.0589 (12)	0.0535 (11)	0.0606 (12)	−0.0032 (9)	0.0210 (10)	0.0111 (10)
C5	0.0459 (10)	0.0477 (10)	0.0435 (10)	−0.0038 (8)	0.0066 (8)	0.0166 (8)
C6	0.0453 (10)	0.0487 (10)	0.0402 (9)	−0.0074 (8)	0.0095 (7)	0.0150 (8)
C7	0.0433 (10)	0.0492 (10)	0.0505 (11)	−0.0040 (8)	0.0096 (8)	0.0168 (8)
C8	0.0435 (9)	0.0562 (11)	0.0468 (10)	−0.0083 (8)	0.0035 (8)	0.0213 (8)
C9	0.0492 (10)	0.0532 (11)	0.0391 (9)	−0.0138 (8)	0.0065 (8)	0.0123 (8)
C10	0.0478 (10)	0.0487 (10)	0.0468 (10)	−0.0070 (8)	0.0111 (8)	0.0125 (8)
C11	0.112 (2)	0.0758 (18)	0.097 (2)	−0.0006 (15)	0.0625 (18)	0.0033 (15)
C12	0.0561 (12)	0.0803 (15)	0.0551 (12)	−0.0094 (11)	−0.0004 (10)	0.0319 (11)
C13	0.0608 (12)	0.0671 (13)	0.0563 (12)	0.0090 (10)	0.0128 (10)	0.0295 (10)
C14	0.0596 (13)	0.0940 (18)	0.0718 (15)	0.0061 (12)	−0.0010 (11)	0.0353 (14)
C15	0.0937 (19)	0.0731 (17)	0.108 (2)	0.0165 (14)	0.0338 (17)	0.0493 (16)
C16	0.0740 (14)	0.0662 (14)	0.0494 (12)	−0.0038 (11)	0.0119 (10)	0.0072 (10)
O1	0.0736 (10)	0.0946 (12)	0.0453 (8)	−0.0151 (9)	0.0010 (7)	0.0295 (8)
O2	0.0562 (8)	0.0723 (10)	0.0627 (9)	0.0146 (7)	0.0165 (7)	0.0249 (8)
O3	0.0590 (8)	0.0579 (8)	0.0434 (7)	−0.0053 (6)	0.0169 (6)	0.0151 (6)
C17	0.0510 (10)	0.0525 (11)	0.0445 (10)	0.0036 (8)	0.0108 (8)	0.0145 (8)
C18	0.0536 (11)	0.0669 (13)	0.0525 (11)	0.0010 (9)	0.0184 (9)	0.0220 (10)
C19	0.0473 (10)	0.0590 (12)	0.0614 (12)	−0.0027 (9)	0.0104 (9)	0.0234 (10)
C20	0.0490 (10)	0.0488 (10)	0.0564 (12)	−0.0015 (8)	0.0088 (9)	0.0134 (9)
C21	0.0468 (10)	0.0492 (10)	0.0462 (10)	0.0066 (8)	0.0114 (8)	0.0130 (8)
C22	0.0501 (10)	0.0530 (11)	0.0443 (10)	0.0060 (8)	0.0139 (8)	0.0166 (8)
C23	0.0517 (10)	0.0465 (10)	0.0475 (10)	−0.0015 (8)	0.0087 (8)	0.0162 (8)
C24	0.0526 (10)	0.0457 (10)	0.0433 (10)	0.0005 (8)	0.0076 (8)	0.0140 (8)
C25	0.0427 (9)	0.0488 (10)	0.0457 (10)	0.0035 (7)	0.0091 (8)	0.0189 (8)
C26	0.0451 (9)	0.0444 (9)	0.0467 (10)	0.0045 (7)	0.0094 (8)	0.0151 (8)
C27	0.0697 (15)	0.0747 (16)	0.0810 (16)	−0.0162 (12)	0.0205 (13)	0.0268 (13)
C28	0.0707 (13)	0.0555 (12)	0.0496 (11)	−0.0083 (10)	0.0152 (10)	0.0116 (9)
C29	0.0632 (13)	0.0551 (12)	0.0500 (11)	0.0036 (9)	0.0145 (10)	0.0065 (9)
C30	0.0680 (14)	0.0671 (14)	0.0559 (13)	0.0026 (11)	0.0024 (11)	0.0113 (10)
C31	0.0866 (17)	0.0659 (15)	0.0707 (15)	0.0164 (12)	0.0193 (13)	0.0126 (12)
C32	0.0918 (18)	0.0867 (17)	0.0575 (13)	−0.0204 (14)	0.0101 (12)	0.0328 (13)
O4	0.0726 (9)	0.0588 (8)	0.0475 (8)	−0.0071 (7)	0.0220 (7)	0.0076 (6)
O5	0.0794 (10)	0.0641 (9)	0.0538 (8)	−0.0213 (8)	0.0213 (8)	0.0138 (7)
O6	0.0636 (9)	0.0718 (9)	0.0521 (8)	−0.0019 (7)	0.0222 (7)	0.0197 (7)

Geometric parameters (Å, º) top

C1—C2	1.354 (3)	C17—C18	1.357 (3)
C1—O1	1.370 (3)	C17—O4	1.383 (2)
C1—C9	1.401 (3)	C17—C25	1.392 (3)
C2—C3	1.432 (4)	C18—C19	1.420 (3)
C2—H2	0.9300	C18—H18	0.9300
C3—C4	1.376 (3)	C19—C20	1.380 (3)
C3—C11	1.510 (3)	C19—C27	1.511 (3)
C4—C10	1.422 (3)	C20—C26	1.429 (3)
C4—H4	0.9300	C20—H20	0.9300
C5—C6	1.387 (3)	C21—C22	1.388 (3)
C5—C10	1.433 (3)	C21—C26	1.435 (3)
C5—C13	1.520 (3)	C21—C29	1.530 (3)
C6—O3	1.391 (2)	C22—O6	1.394 (2)
C6—C7	1.427 (3)	C22—C23	1.429 (3)
C7—C8	1.357 (3)	C23—O5	1.358 (2)
C7—O2	1.363 (2)	C23—C24	1.359 (3)
C8—C9	1.393 (3)	C24—C25	1.391 (3)
C8—C12	1.504 (3)	C24—C28	1.504 (3)
C9—C10	1.398 (3)	C25—C26	1.404 (3)
C11—H11A	0.9600	C27—H27A	0.9600
C11—H11B	0.9600	C27—H27B	0.9600
C11—H11C	0.9600	C27—H27C	0.9600
C12—O1	1.460 (3)	C28—O4	1.472 (2)
C12—H12A	0.9700	C28—H28A	0.9700
C12—H12B	0.9700	C28—H28B	0.9700
C13—C15	1.510 (3)	C29—C31	1.494 (3)
C13—C14	1.526 (3)	C29—C30	1.514 (3)
C13—H13	0.9800	C29—H29	0.9800
C14—H14A	0.9600	C30—H30A	0.9600
C14—H14B	0.9600	C30—H30B	0.9600
C14—H14C	0.9600	C30—H30C	0.9600
C15—H15A	0.9600	C31—H31A	0.9600
C15—H15B	0.9600	C31—H31B	0.9600
C15—H15C	0.9600	C31—H31C	0.9600
C16—O3	1.436 (2)	C32—O6	1.432 (3)
C16—H16A	0.9600	C32—H32A	0.9600
C16—H16B	0.9600	C32—H32B	0.9600
C16—H16C	0.9600	C32—H32C	0.9600
O2—H2A	0.8200	O5—H5	0.8200

C2—C1—O1	128.9 (2)	C18—C17—O4	128.27 (18)
C2—C1—C9	120.4 (2)	C18—C17—C25	121.37 (19)
O1—C1—C9	110.6 (2)	O4—C17—C25	110.36 (17)
C1—C2—C3	117.9 (2)	C17—C18—C19	116.92 (19)
C1—C2—H2	121.1	C17—C18—H18	121.5
C3—C2—H2	121.1	C19—C18—H18	121.5
C4—C3—C2	121.3 (2)	C20—C19—C18	122.20 (19)
C4—C3—C11	120.9 (3)	C20—C19—C27	119.9 (2)
C2—C3—C11	117.8 (2)	C18—C19—C27	117.9 (2)
C3—C4—C10	121.6 (2)	C19—C20—C26	121.41 (19)
C3—C4—H4	119.2	C19—C20—H20	119.3
C10—C4—H4	119.2	C26—C20—H20	119.3
C6—C5—C10	117.24 (17)	C22—C21—C26	117.52 (17)
C6—C5—C13	119.53 (17)	C22—C21—C29	119.33 (18)
C10—C5—C13	123.23 (18)	C26—C21—C29	123.13 (18)
C5—C6—O3	121.02 (16)	C21—C22—O6	121.39 (17)
C5—C6—C7	124.92 (17)	C21—C22—C23	124.49 (18)
O3—C6—C7	113.94 (16)	O6—C22—C23	114.09 (17)
C8—C7—O2	119.94 (18)	O5—C23—C24	120.13 (17)
C8—C7—C6	117.77 (18)	O5—C23—C22	121.93 (18)
O2—C7—C6	122.29 (17)	C24—C23—C22	117.94 (17)
C7—C8—C9	117.79 (18)	C23—C24—C25	118.00 (17)
C7—C8—C12	135.5 (2)	C23—C24—C28	134.59 (18)
C9—C8—C12	106.72 (18)	C25—C24—C28	107.41 (17)
C8—C9—C10	126.68 (18)	C24—C25—C17	109.77 (17)
C8—C9—C1	109.45 (19)	C24—C25—C26	126.36 (18)
C10—C9—C1	123.9 (2)	C17—C25—C26	123.87 (18)
C9—C10—C4	114.85 (18)	C25—C26—C20	114.18 (17)
C9—C10—C5	115.56 (18)	C25—C26—C21	115.56 (17)
C4—C10—C5	129.58 (19)	C20—C26—C21	130.26 (18)
C3—C11—H11A	109.5	C19—C27—H27A	109.5
C3—C11—H11B	109.5	C19—C27—H27B	109.5
H11A—C11—H11B	109.5	H27A—C27—H27B	109.5
C3—C11—H11C	109.5	C19—C27—H27C	109.5
H11A—C11—H11C	109.5	H27A—C27—H27C	109.5
H11B—C11—H11C	109.5	H27B—C27—H27C	109.5
O1—C12—C8	104.78 (18)	O4—C28—C24	103.99 (15)
O1—C12—H12A	110.8	O4—C28—H28A	111.0
C8—C12—H12A	110.8	C24—C28—H28A	111.0
O1—C12—H12B	110.8	O4—C28—H28B	111.0
C8—C12—H12B	110.8	C24—C28—H28B	111.0
H12A—C12—H12B	108.9	H28A—C28—H28B	109.0
C15—C13—C5	112.45 (19)	C31—C29—C30	112.4 (2)
C15—C13—C14	113.3 (2)	C31—C29—C21	114.58 (19)
C5—C13—C14	113.28 (18)	C30—C29—C21	112.46 (17)
C15—C13—H13	105.6	C31—C29—H29	105.5
C5—C13—H13	105.6	C30—C29—H29	105.5
C14—C13—H13	105.6	C21—C29—H29	105.5
C13—C14—H14A	109.5	C29—C30—H30A	109.5
C13—C14—H14B	109.5	C29—C30—H30B	109.5
H14A—C14—H14B	109.5	H30A—C30—H30B	109.5
C13—C14—H14C	109.5	C29—C30—H30C	109.5
H14A—C14—H14C	109.5	H30A—C30—H30C	109.5
H14B—C14—H14C	109.5	H30B—C30—H30C	109.5
C13—C15—H15A	109.5	C29—C31—H31A	109.5
C13—C15—H15B	109.5	C29—C31—H31B	109.5
H15A—C15—H15B	109.5	H31A—C31—H31B	109.5
C13—C15—H15C	109.5	C29—C31—H31C	109.5
H15A—C15—H15C	109.5	H31A—C31—H31C	109.5
H15B—C15—H15C	109.5	H31B—C31—H31C	109.5
O3—C16—H16A	109.5	O6—C32—H32A	109.5
O3—C16—H16B	109.5	O6—C32—H32B	109.5
H16A—C16—H16B	109.5	H32A—C32—H32B	109.5
O3—C16—H16C	109.5	O6—C32—H32C	109.5
H16A—C16—H16C	109.5	H32A—C32—H32C	109.5
H16B—C16—H16C	109.5	H32B—C32—H32C	109.5
C1—O1—C12	108.40 (16)	C17—O4—C28	108.37 (15)
C7—O2—H2A	109.5	C23—O5—H5	109.5
C6—O3—C16	114.15 (14)	C22—O6—C32	112.83 (17)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2A···O3	0.82	2.28	2.723 (2)	114
O2—H2A···O4ⁱ	0.82	2.11	2.809 (2)	144
O5—H5···O3	0.82	2.13	2.7843 (19)	137
O5—H5···O6	0.82	2.27	2.719 (2)	115
C12—H12B···O2ⁱⁱ	0.97	2.48	3.445 (3)	171

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

Experimental details

Crystal data
Chemical formula	C₁₆H₁₈O₃
M_r	258.30
Crystal system, space group	Triclinic, P1
Temperature (K)	293
a, b, c (Å)	10.0275 (5), 11.1058 (6), 13.2938 (8)
α, β, γ (°)	107.797 (5), 103.896 (5), 90.435 (4)
V (Å³)	1363.08 (13)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	0.69
Crystal size (mm)	0.40 × 0.34 × 0.28

Data collection
Diffractometer	Oxford Diffraction Xcalibur Ruby diffractometer
Absorption correction	Multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)
T_min, T_max	0.925, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	10119, 5476, 3775
R_int	0.027
(sin θ/λ)_max (Å⁻¹)	0.629

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.050, 0.158, 1.04
No. of reflections	5476
No. of parameters	354
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.45, −0.22

Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2A···O3	0.82	2.28	2.723 (2)	114
O2—H2A···O4ⁱ	0.82	2.11	2.809 (2)	144
O5—H5···O3	0.82	2.13	2.7843 (19)	137
O5—H5···O6	0.82	2.27	2.719 (2)	115
C12—H12B···O2ⁱⁱ	0.97	2.48	3.445 (3)	171

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

Acknowledgements

This work was supported by the CRDF project UZB2–31001-TA02.

References

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