Bispuupehenone from the South Chinese Sea sponge Dysidea sp.

Qin, S.; Shi, L.; Li, J.; Guo, Y.-W.

doi:10.1107/S1600536808011987

organic compounds

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ISSN: 2056-9890

Volume 64| Part 5| May 2008| Pages o946-o947

doi:10.1107/S1600536808011987

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Bispuupehenone from the South Chinese Sea sponge Dysidea sp.

Song Qin,^a ^* Lei Shi,^b Jia Li ^b and Yue-Wei Guo ^a

^aState Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, People's Republic of China, and ^bChinese National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, People's Republic of China
^*Correspondence e-mail: ywguo@mail.shcnc.ac.cn

(Received 28 February 2008; accepted 25 April 2008; online 30 April 2008)

Bispuupehenone, C₄₂H₅₄O₆, formally results from dimerization of puupehenone, which is constructed of sesquiterpene and benzene units. Bispuupehenone was isolated from the South China Sea sponge Dysidea sp. and the single-crystal X-ray diffraction analysis confirmed the previously reported structure. The molecule is located on a twofold axis and the dimerization forms two fused dibenzopyran systems related by symmetry. In the asymmetric unit, the two cyclohexane rings adopt chair conformations, while the two pyran rings adopt half-chair conformations. The relative stereochemistry and configurations for the ring junctions are in agreement with the structure reported previously.

Related literature

The title compound was first isolated from the Pacific marine sponge Heteronema sp., see Amade et al. (1983 ). For the biological and pharmaceutical activity of puupehenone, see: Barrero et al. (1998 , 1999 ); Castro et al. (2004 ); Ciavatta et al. (2007 ); Longley et al. (1993 ); Kohmoto et al. (1987 ); Takamatsu et al. (2003 ). For the synthesis and semi-synthesis of puupehenone and its derivatives, see: Hamann (2003 ); Alvarez-Manzaneda et al. (2005 , 2007 ).

Experimental

Crystal data

C₄₂H₅₄O₆
M_r = 654.85
Tetragonal, P 4₁ 2₁ 2
a = 13.5981 (10) Å
c = 18.7260 (19) Å
V = 3462.6 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 293 (2) K
0.39 × 0.24 × 0.14 mm

Data collection

Bruker APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2000 ) T_min = 0.743, T_max = 0.990
20532 measured reflections
2219 independent reflections
1644 reflections with I > 2σ(I)
R_int = 0.110

Refinement

R[F² > 2σ(F²)] = 0.045
wR(F²) = 0.113
S = 0.94
2219 reflections
225 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); 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: 10.1107/S1600536808011987/bh2164sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808011987/bh2164Isup2.hkl

checkCIF report

Comment top

Bispuupehenone (I) was firstly isolated from Pacific marine sponge Heteronema sp. (Amade et al., 1983), and was considered to be generated from co-occurring puupehenone (II) (Fig. 1) by in vitro oxidative coupling. The benzopyrane structure for the dimer is deduced by the comparison of its UV spectrum data with those of a simple dibenzofuran and a simple benzopyran. Although compound (II) and its derivatives have been reported to display a wide range of important biological activities, including antiviral, antifungal, antimalarial, and antitumor activities (Barrero et al., 1998, 1999; Longley et al., 1993; Castro et al., 2004; Ciavatta et al., 2007; Kohmoto et al., 1987; Takamatsu et al., 2003), the biological properties of (I) have been seldom reported. Synthesis and semi-synthesis of puupehenone and its derivatives have been published (Hamann, 2003); Alvarez-Manzaneda et al., 2005, 2007).

As part of our research project on the study of the South China Sea marine organisms, a sample of the sponge Dysidea sp. was collected off the Lingshui Bay, Hainan Province, China, and was chemically investigated. Bispuupehenone, (I), was isolated and crystallized from the Et₂O-soluble fraction of the acetone extract of the animal, and the structure of (I) was firstly elucidated by spectroscopic methods, NMR, UV and MS, and eventually confirmed through X-ray diffraction analysis. Herein, we report the X-ray structure of (I).

The projection of bispuupehenone is shown in Figure 2. In the structure, two puupehenone moieties are connected through two O atoms and a C—C bond between benzene rings, forming a benzopyran moiety at the midpoint of the axial symmetric molecule. Rings A and B of (I) are in chair conformations, while rings C and D adopt half-chair conformations. Moreover, the trans junction between rings A/B and the cis junction between rings B/C are in agreement with the structure reported previously.

Bispuupehenone was tested for the inhibitory activities against hPTP1B (human protein tyrosine phosphatase 1B), a key target for the treatment of Type-II diabetes and obesity, and showed excellent inhibitory effect with IC₅₀ value of 0.98 mg ml^-1. Other bioassays, such as antibacterial and anti-inflammatory, are currently ongoing.

Related literature top

The title compound was first isolated from the Pacific marine sponge Heteronema sp., see Amade et al. (1983). For the biological and pharmaceutical activity of puupehenone, see: Barrero et al. (1998, 1999); Castro et al. (2004); Ciavatta et al. (2007); Longley et al. (1993); Kohmoto et al. (1987); Takamatsu et al. (2003). For the synthesis and semi-synthesis of puupehenone and its derivatives, see: Hamann (2003); Alvarez-Manzaneda et al. (2005, 2007).

Experimental top

The specimens of sponge were collected from Lingshui Bay, Hainan Province, China, in July 2004, and identified as Dysidea sp. by Professor J.-H. Li of the Institute of Oceanology, Chinese Academy of Sciences. A voucher specimen (LS-210) is available for inspection at the Herbarium of Shanghai Institute of Materia Medica, CAS. The frozen animals (dry weight 96.3 g) were cut into small pieces and exhaustively extracted with acetone (3×3 L). The organic extract was evaporated to give a residue, which was partitioned between Et₂O and H₂O. The Et₂O solution was concentrated under reduced pressure to give a dark brown residue (4.7 g), which was fractionated by gradient silica gel column chromatography [0–100% acetone in light petroleum ether (PE)], yielding seven fractions (A···G). The fraction C eluted by PE/Me₂CO (95:5) was further purified on a second silica gel column chromatography eluting with PE—Et₂O (90:10) to afford (I) (14.3 mg). Crystals suitable for X-ray analysis were obtained by slow evaporation from a chloroform solution.

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); 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 structures of bispuupehenone (I) and puupehenone (II).
	Fig. 2. The projection of (I) showing the atom-labeling scheme.

Bispuupehenone top

Crystal data top

C₄₂H₅₄O₆	D_x = 1.256 Mg m⁻³
M_r = 654.85	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, P4₁2₁2	Cell parameters from 4034 reflections
Hall symbol: P 4abw 2nw	θ = 4.8–54.2°
a = 13.5981 (10) Å	µ = 0.08 mm⁻¹
c = 18.7260 (19) Å	T = 293 K
V = 3462.6 (5) Å³	Prismatic, colourless
Z = 4	0.39 × 0.24 × 0.14 mm
F(000) = 1416

Data collection top

Bruker APEX CCD area-detector diffractometer	2219 independent reflections
Radiation source: fine-focus sealed tube	1644 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.110
ϕ and ω scans	θ_max = 27.0°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −16→17
T_min = 0.743, T_max = 0.990	k = −17→17
20532 measured reflections	l = −11→23

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)] = 0.045	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.113	H atoms treated by a mixture of independent and constrained refinement
S = 0.95	w = 1/[σ²(F_o²) + (0.07P)²] where P = (F_o² + 2F_c²)/3
2219 reflections	(Δ/σ)_max = 0.007
225 parameters	Δρ_max = 0.23 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³

Crystal data top

C₄₂H₅₄O₆	Z = 4
M_r = 654.85	Mo Kα radiation
Tetragonal, P4₁2₁2	µ = 0.08 mm⁻¹
a = 13.5981 (10) Å	T = 293 K
c = 18.7260 (19) Å	0.39 × 0.24 × 0.14 mm
V = 3462.6 (5) Å³

Data collection top

Bruker APEX CCD area-detector diffractometer	2219 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2000)	1644 reflections with I > 2σ(I)
T_min = 0.743, T_max = 0.990	R_int = 0.110
20532 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.045	0 restraints
wR(F²) = 0.113	H atoms treated by a mixture of independent and constrained refinement
S = 0.95	Δρ_max = 0.23 e Å⁻³
2219 reflections	Δρ_min = −0.20 e Å⁻³
225 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.15743 (13)	0.55657 (12)	0.08619 (8)	0.0429 (5)
O2	0.12262 (16)	0.48461 (14)	0.33312 (11)	0.0530 (5)
O3	0.34879 (12)	0.77308 (13)	0.13171 (8)	0.0415 (4)
C1	0.1684 (2)	0.87117 (19)	−0.00763 (14)	0.0499 (7)
H1A	0.1694	0.9034	0.0386	0.060*
H1B	0.2340	0.8757	−0.0277	0.060*
C2	0.0968 (3)	0.9254 (2)	−0.05633 (14)	0.0637 (9)
H2A	0.0322	0.9261	−0.0345	0.076*
H2B	0.1183	0.9930	−0.0619	0.076*
C3	0.0904 (3)	0.8771 (2)	−0.12908 (15)	0.0681 (9)
H3A	0.1538	0.8820	−0.1525	0.082*
H3B	0.0430	0.9126	−0.1580	0.082*
C4	0.0601 (3)	0.7683 (2)	−0.12559 (14)	0.0573 (8)
C5	0.1302 (2)	0.71542 (19)	−0.07258 (12)	0.0431 (6)
H5	0.1954	0.7217	−0.0944	0.052*
C6	0.1141 (2)	0.6044 (2)	−0.06599 (13)	0.0474 (7)
H6A	0.0577	0.5915	−0.0356	0.057*
H6B	0.1010	0.5765	−0.1127	0.057*
C7	0.2055 (2)	0.5575 (2)	−0.03409 (13)	0.0484 (7)
H7A	0.1950	0.4871	−0.0303	0.058*
H7B	0.2604	0.5679	−0.0664	0.058*
C8	0.2325 (2)	0.59716 (19)	0.03840 (13)	0.0411 (6)
C9	0.23190 (19)	0.71109 (17)	0.04069 (12)	0.0371 (6)
H9	0.2905	0.7323	0.0145	0.045*
C10	0.14213 (18)	0.76213 (18)	0.00287 (13)	0.0389 (6)
C11	0.0747 (3)	0.7242 (3)	−0.20075 (15)	0.0850 (12)
H11A	0.0422	0.7649	−0.2354	0.127*
H11B	0.0472	0.6592	−0.2022	0.127*
H11C	0.1436	0.7211	−0.2115	0.127*
C12	−0.0502 (2)	0.7571 (3)	−0.10853 (18)	0.0746 (10)
H12A	−0.0662	0.7956	−0.0672	0.112*
H12B	−0.0647	0.6892	−0.0993	0.112*
H12C	−0.0884	0.7795	−0.1485	0.112*
C13	0.0492 (2)	0.7539 (2)	0.04922 (13)	0.0462 (6)
H13A	0.0646	0.7722	0.0975	0.069*
H13B	0.0257	0.6873	0.0483	0.069*
H13C	−0.0006	0.7969	0.0308	0.069*
C14	0.24566 (18)	0.74743 (19)	0.11748 (12)	0.0365 (5)
H14	0.2065	0.8074	0.1231	0.044*
C15	0.3325 (2)	0.5555 (2)	0.06039 (15)	0.0539 (7)
H15A	0.3455	0.5721	0.1093	0.081*
H15B	0.3829	0.5829	0.0305	0.081*
H15C	0.3319	0.4852	0.0551	0.081*
C16	0.21009 (17)	0.67425 (18)	0.17229 (12)	0.0355 (6)
C17	0.22961 (17)	0.69613 (18)	0.24324 (13)	0.0351 (5)
C18	0.20089 (17)	0.63566 (18)	0.29797 (12)	0.0359 (5)
C19	0.15135 (18)	0.54863 (18)	0.28072 (13)	0.0384 (6)
C20	0.13528 (19)	0.52376 (18)	0.21062 (13)	0.0401 (6)
H20	0.1029	0.4655	0.1997	0.048*
C21	0.16728 (18)	0.58544 (18)	0.15546 (13)	0.0367 (6)
H2	0.149 (3)	0.513 (3)	0.3750 (19)	0.086 (11)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0538 (11)	0.0380 (9)	0.0370 (9)	−0.0081 (8)	0.0003 (8)	−0.0055 (8)
O2	0.0695 (13)	0.0420 (10)	0.0474 (11)	−0.0153 (10)	0.0097 (10)	0.0052 (9)
O3	0.0395 (9)	0.0490 (10)	0.0360 (9)	−0.0103 (8)	0.0026 (8)	−0.0008 (8)
C1	0.0642 (18)	0.0418 (14)	0.0436 (14)	−0.0107 (13)	−0.0004 (14)	0.0011 (13)
C2	0.087 (2)	0.0442 (16)	0.0597 (19)	−0.0007 (17)	−0.0084 (18)	0.0115 (14)
C3	0.092 (3)	0.0619 (19)	0.0507 (18)	−0.0038 (18)	−0.0139 (18)	0.0132 (16)
C4	0.072 (2)	0.0574 (18)	0.0421 (15)	−0.0089 (15)	−0.0117 (15)	0.0084 (15)
C5	0.0527 (15)	0.0435 (14)	0.0333 (13)	−0.0078 (13)	0.0020 (12)	−0.0012 (11)
C6	0.0624 (18)	0.0469 (15)	0.0329 (13)	−0.0116 (14)	−0.0030 (13)	−0.0100 (12)
C7	0.0604 (18)	0.0436 (15)	0.0412 (14)	0.0014 (13)	0.0053 (14)	−0.0076 (12)
C8	0.0461 (15)	0.0397 (13)	0.0373 (13)	0.0023 (12)	0.0052 (12)	−0.0056 (12)
C9	0.0410 (13)	0.0376 (12)	0.0328 (13)	−0.0041 (11)	0.0052 (11)	−0.0029 (11)
C10	0.0441 (14)	0.0387 (13)	0.0339 (12)	−0.0051 (11)	0.0019 (11)	0.0006 (11)
C11	0.134 (4)	0.081 (2)	0.0400 (18)	−0.012 (3)	−0.016 (2)	0.0019 (17)
C12	0.071 (2)	0.080 (2)	0.073 (2)	−0.0043 (19)	−0.0276 (18)	0.006 (2)
C13	0.0454 (15)	0.0527 (16)	0.0405 (14)	0.0016 (14)	0.0047 (12)	−0.0006 (13)
C14	0.0366 (12)	0.0396 (13)	0.0332 (13)	−0.0056 (11)	−0.0004 (10)	0.0001 (11)
C15	0.0551 (18)	0.0540 (17)	0.0526 (16)	0.0122 (14)	0.0044 (14)	−0.0041 (14)
C16	0.0325 (12)	0.0365 (13)	0.0375 (13)	−0.0026 (10)	0.0022 (11)	−0.0009 (11)
C17	0.0318 (12)	0.0374 (12)	0.0360 (13)	−0.0021 (10)	0.0019 (11)	−0.0025 (11)
C18	0.0353 (12)	0.0404 (13)	0.0321 (13)	−0.0011 (11)	0.0022 (10)	−0.0017 (11)
C19	0.0402 (14)	0.0343 (13)	0.0407 (13)	−0.0035 (11)	0.0071 (11)	0.0036 (11)
C20	0.0432 (14)	0.0341 (12)	0.0430 (14)	−0.0062 (11)	0.0003 (12)	−0.0051 (11)
C21	0.0380 (13)	0.0375 (13)	0.0345 (13)	−0.0014 (11)	0.0002 (11)	−0.0047 (11)

Geometric parameters (Å, º) top

O1—C21	1.362 (3)	C8—C9	1.550 (3)
O1—C8	1.465 (3)	C9—C14	1.532 (3)
O2—C19	1.369 (3)	C9—C10	1.573 (3)
O2—H2	0.95 (4)	C9—H9	0.9800
O3—C18ⁱ	1.380 (3)	C10—C13	1.537 (3)
O3—C14	1.469 (3)	C11—H11A	0.9600
C1—C2	1.524 (4)	C11—H11B	0.9600
C1—C10	1.538 (3)	C11—H11C	0.9600
C1—H1A	0.9700	C12—H12A	0.9600
C1—H1B	0.9700	C12—H12B	0.9600
C2—C3	1.515 (4)	C12—H12C	0.9600
C2—H2A	0.9700	C13—H13A	0.9600
C2—H2B	0.9700	C13—H13B	0.9600
C3—C4	1.536 (5)	C13—H13C	0.9600
C3—H3A	0.9700	C14—C16	1.509 (3)
C3—H3B	0.9700	C14—H14	0.9800
C4—C12	1.541 (5)	C15—H15A	0.9600
C4—C11	1.543 (4)	C15—H15B	0.9600
C4—C5	1.553 (4)	C15—H15C	0.9600
C5—C6	1.530 (4)	C16—C21	1.377 (3)
C5—C10	1.558 (3)	C16—C17	1.387 (3)
C5—H5	0.9800	C17—C18	1.371 (3)
C6—C7	1.520 (4)	C17—C17ⁱ	1.450 (5)
C6—H6A	0.9700	C18—O3ⁱ	1.380 (3)
C6—H6B	0.9700	C18—C19	1.399 (4)
C7—C8	1.506 (3)	C19—C20	1.373 (3)
C7—H7A	0.9700	C20—C21	1.400 (3)
C7—H7B	0.9700	C20—H20	0.9300
C8—C15	1.530 (4)

C21—O1—C8	113.87 (18)	C10—C9—H9	106.0
C19—O2—H2	103 (2)	C13—C10—C1	109.5 (2)
C18ⁱ—O3—C14	112.36 (18)	C13—C10—C5	113.4 (2)
C2—C1—C10	113.2 (2)	C1—C10—C5	107.5 (2)
C2—C1—H1A	108.9	C13—C10—C9	110.58 (19)
C10—C1—H1A	108.9	C1—C10—C9	107.6 (2)
C2—C1—H1B	108.9	C5—C10—C9	108.0 (2)
C10—C1—H1B	108.9	C4—C11—H11A	109.5
H1A—C1—H1B	107.7	C4—C11—H11B	109.5
C3—C2—C1	111.4 (3)	H11A—C11—H11B	109.5
C3—C2—H2A	109.3	C4—C11—H11C	109.5
C1—C2—H2A	109.3	H11A—C11—H11C	109.5
C3—C2—H2B	109.3	H11B—C11—H11C	109.5
C1—C2—H2B	109.3	C4—C12—H12A	109.5
H2A—C2—H2B	108.0	C4—C12—H12B	109.5
C2—C3—C4	113.2 (3)	H12A—C12—H12B	109.5
C2—C3—H3A	108.9	C4—C12—H12C	109.5
C4—C3—H3A	108.9	H12A—C12—H12C	109.5
C2—C3—H3B	108.9	H12B—C12—H12C	109.5
C4—C3—H3B	108.9	C10—C13—H13A	109.5
H3A—C3—H3B	107.7	C10—C13—H13B	109.5
C3—C4—C12	111.4 (3)	H13A—C13—H13B	109.5
C3—C4—C11	107.5 (3)	C10—C13—H13C	109.5
C12—C4—C11	106.0 (3)	H13A—C13—H13C	109.5
C3—C4—C5	108.0 (2)	H13B—C13—H13C	109.5
C12—C4—C5	114.8 (2)	O3—C14—C16	109.82 (18)
C11—C4—C5	108.9 (3)	O3—C14—C9	111.31 (19)
C6—C5—C4	114.9 (2)	C16—C14—C9	112.7 (2)
C6—C5—C10	110.1 (2)	O3—C14—H14	107.6
C4—C5—C10	117.1 (2)	C16—C14—H14	107.6
C6—C5—H5	104.4	C9—C14—H14	107.6
C4—C5—H5	104.4	C8—C15—H15A	109.5
C10—C5—H5	104.4	C8—C15—H15B	109.5
C7—C6—C5	109.2 (2)	H15A—C15—H15B	109.5
C7—C6—H6A	109.8	C8—C15—H15C	109.5
C5—C6—H6A	109.8	H15A—C15—H15C	109.5
C7—C6—H6B	109.8	H15B—C15—H15C	109.5
C5—C6—H6B	109.8	C21—C16—C17	119.2 (2)
H6A—C6—H6B	108.3	C21—C16—C14	123.9 (2)
C8—C7—C6	113.7 (2)	C17—C16—C14	116.7 (2)
C8—C7—H7A	108.8	C18—C17—C16	122.2 (2)
C6—C7—H7A	108.8	C18—C17—C17ⁱ	119.0 (3)
C8—C7—H7B	108.8	C16—C17—C17ⁱ	116.7 (3)
C6—C7—H7B	108.8	C17—C18—O3ⁱ	123.3 (2)
H7A—C7—H7B	107.7	C17—C18—C19	118.1 (2)
O1—C8—C7	104.3 (2)	O3ⁱ—C18—C19	118.3 (2)
O1—C8—C15	108.4 (2)	O2—C19—C20	118.9 (2)
C7—C8—C15	109.0 (2)	O2—C19—C18	120.6 (2)
O1—C8—C9	110.86 (19)	C20—C19—C18	120.4 (2)
C7—C8—C9	112.5 (2)	C19—C20—C21	120.6 (2)
C15—C8—C9	111.6 (2)	C19—C20—H20	119.7
C14—C9—C8	110.36 (19)	C21—C20—H20	119.7
C14—C9—C10	112.0 (2)	O1—C21—C16	120.8 (2)
C8—C9—C10	115.6 (2)	O1—C21—C20	120.0 (2)
C14—C9—H9	106.0	C16—C21—C20	119.2 (2)
C8—C9—H9	106.0

C10—C1—C2—C3	−57.4 (3)	C14—C9—C10—C1	67.9 (2)
C1—C2—C3—C4	57.2 (4)	C8—C9—C10—C1	−164.5 (2)
C2—C3—C4—C12	74.3 (3)	C14—C9—C10—C5	−176.30 (19)
C2—C3—C4—C11	−169.9 (3)	C8—C9—C10—C5	−48.7 (3)
C2—C3—C4—C5	−52.6 (4)	C18ⁱ—O3—C14—C16	−50.0 (2)
C3—C4—C5—C6	−176.6 (3)	C18ⁱ—O3—C14—C9	−175.53 (19)
C12—C4—C5—C6	58.5 (4)	C8—C9—C14—O3	97.3 (2)
C11—C4—C5—C6	−60.1 (3)	C10—C9—C14—O3	−132.3 (2)
C3—C4—C5—C10	52.0 (3)	C8—C9—C14—C16	−26.6 (3)
C12—C4—C5—C10	−73.0 (3)	C10—C9—C14—C16	103.8 (2)
C11—C4—C5—C10	168.4 (2)	O3—C14—C16—C21	−126.5 (2)
C4—C5—C6—C7	160.9 (2)	C9—C14—C16—C21	−1.7 (3)
C10—C5—C6—C7	−64.4 (3)	O3—C14—C16—C17	48.3 (3)
C5—C6—C7—C8	58.8 (3)	C9—C14—C16—C17	173.0 (2)
C21—O1—C8—C7	−178.8 (2)	C21—C16—C17—C18	−5.2 (4)
C21—O1—C8—C15	65.2 (3)	C14—C16—C17—C18	179.8 (2)
C21—O1—C8—C9	−57.6 (3)	C21—C16—C17—C17ⁱ	158.50 (17)
C6—C7—C8—O1	72.2 (3)	C14—C16—C17—C17ⁱ	−16.5 (2)
C6—C7—C8—C15	−172.2 (2)	C16—C17—C18—O3ⁱ	174.0 (2)
C6—C7—C8—C9	−47.9 (3)	C17ⁱ—C17—C18—O3ⁱ	10.7 (3)
O1—C8—C9—C14	55.9 (3)	C16—C17—C18—C19	0.8 (4)
C7—C8—C9—C14	172.2 (2)	C17ⁱ—C17—C18—C19	−162.49 (17)
C15—C8—C9—C14	−64.9 (3)	C17—C18—C19—O2	178.8 (2)
O1—C8—C9—C10	−72.5 (3)	O3ⁱ—C18—C19—O2	5.2 (3)
C7—C8—C9—C10	43.8 (3)	C17—C18—C19—C20	2.1 (4)
C15—C8—C9—C10	166.6 (2)	O3ⁱ—C18—C19—C20	−171.5 (2)
C2—C1—C10—C13	−70.9 (3)	O2—C19—C20—C21	−177.3 (2)
C2—C1—C10—C5	52.7 (3)	C18—C19—C20—C21	−0.6 (4)
C2—C1—C10—C9	168.9 (2)	C8—O1—C21—C16	28.2 (3)
C6—C5—C10—C13	−64.4 (3)	C8—O1—C21—C20	−150.7 (2)
C4—C5—C10—C13	69.2 (3)	C17—C16—C21—O1	−172.3 (2)
C6—C5—C10—C1	174.4 (2)	C14—C16—C21—O1	2.3 (4)
C4—C5—C10—C1	−52.0 (3)	C17—C16—C21—C20	6.5 (4)
C6—C5—C10—C9	58.5 (3)	C14—C16—C21—C20	−178.9 (2)
C4—C5—C10—C9	−167.9 (2)	C19—C20—C21—O1	175.1 (2)
C14—C9—C10—C13	−51.7 (3)	C19—C20—C21—C16	−3.7 (4)
C8—C9—C10—C13	75.9 (3)

Symmetry code: (i) −y+1, −x+1, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O3ⁱ	0.95 (4)	2.16 (4)	2.753 (3)	120 (3)

Symmetry code: (i) −y+1, −x+1, −z+1/2.

Experimental details

Crystal data
Chemical formula	C₄₂H₅₄O₆
M_r	654.85
Crystal system, space group	Tetragonal, P4₁2₁2
Temperature (K)	293
a, c (Å)	13.5981 (10), 18.7260 (19)
V (Å³)	3462.6 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.39 × 0.24 × 0.14

Data collection
Diffractometer	Bruker APEX CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2000)
T_min, T_max	0.743, 0.990
No. of measured, independent and observed [I > 2σ(I)] reflections	20532, 2219, 1644
R_int	0.110
(sin θ/λ)_max (Å⁻¹)	0.638

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.045, 0.113, 0.95
No. of reflections	2219
No. of parameters	225
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.20

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

The research work was financially supported by the National Marine `863' Project (No. 2006 A A09Z412), the Natural Science Foundation of China (Nos. 3073108, 20772136, and 20721003), CAS Key Project (grant KSCX2-YW-R-18) and STCSM Projects (No. 017XD14036 and 06DZ22028), and partially funded by a grant from the Syngenta-SIMM-PhD Studentship Project.

References

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