4,5,6-Tri-O-acetyl-2,3-di-S-ethyl-2,3-dithio-d-allose diethyl dithio­acetal

Xi, X.-D.; Shi, D.-X.; Li, H.; Li, Y.-Z.; Wu, Q.-P.

doi:10.1107/S1600536809015694

organic compounds

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ISSN: 2056-9890

Volume 65| Part 6| June 2009| Page o1227

doi:10.1107/S1600536809015694

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4,5,6-Tri-O-acetyl-2,3-di-S-ethyl-2,3-dithio-D-allose diethyl dithioacetal

Xiao-Dong Xi,^a Da-Xin Shi,^a Hui Li,^b Yun-Zheng Li ^a and Qin-Pei Wu ^a ^*

^aSchool of Chemical Engineering and Environment, Beijing Institute of Technology, Beijing 100081, People's Republic of China, and ^bSchool of Science, Beijing Institute of Technology, Beijing 100081, People's Republic of China
^*Correspondence e-mail: qpwu@bit.edu.cn

(Received 14 April 2009; accepted 27 April 2009; online 7 May 2009)

The title compound, C₂₀H₃₆O₆S₄, was obtained by ethanethiolysis of 3,5,6-tri-O-acetyl-1,2-O-isopropylidene-α-D-glucofuranose. One of the ethyl groups is disordered over two sites with refined occupancies of 0.869 (6) and 0.131 (6). Compared with the precursor, the absolute configuration of the stereocenters at positions C-3 and C-2 are inverted and maintained, respectively.

Related literature

For the bioactiviy of nucleosides, see: Zhang et al. (2007 ); Merino et al. (2008 ). For the structure of the precursor, 3,5,6-tri-O-acetyl-1,2-O-isopropylidene-α-D-glucofuranose, see: Wu et al. (2009 ). For related structures, see: Bethel & Ferrier (1972 ); Berrang & Hortor (1970 ); Divjaković et al. (1992 ).

Experimental

Crystal data

C₂₀H₃₆O₆S₄
M_r = 500.73
Monoclinic, P 2₁
a = 8.3395 (12) Å
b = 16.726 (2) Å
c = 9.2027 (14) Å
β = 95.772 (5)°
V = 1277.2 (3) Å³
Z = 2
Mo Kα radiation
μ = 0.40 mm⁻¹
T = 113 K
0.26 × 0.20 × 0.18 mm

Data collection

Rigaku Saturn diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005 ) T_min = 0.902, T_max = 0.931
16052 measured reflections
6060 independent reflections
5802 reflections with I > 2σ(I)
R_int = 0.032

Refinement

R[F² > 2σ(F²)] = 0.032
wR(F²) = 0.066
S = 1.04
6060 reflections
298 parameters
23 restraints
H-atom parameters constrained
Δρ_max = 0.20 e Å⁻³
Δρ_min = −0.29 e Å⁻³
Absolute structure: Flack (1983 ), 2919 Friedel pairs
Flack parameter: −0.03 (4)

Data collection: CrystalClear (Rigaku/MSC, 2005); cell refinement: CrystalClear; data reduction: CrystalClear; 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 global, I. DOI: 10.1107/S1600536809015694/lh2804sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809015694/lh2804Isup2.hkl

checkCIF report

Comment top

Nucleosides are important compounds due to their extensive bioactivity in antitumor and antivirus (Zhang et al., 2007, Merino et al., 2008). In the course of our studies in the synthesis of nucleoside analogues, an ethanethio substituted thioacetal product was obtained as ethanethiolysis of 3,5,6-tri-O-acetyl-1,2-O-isopropylidene-α-D-glucofuranose (Wu et al., 2009). The purpose of the structure determination was to establish the position of the substituents of the ethanethio groups and the molecular conformation of the title compound. In contrast to its precursor, the absolute configuration of C-3 and C-2 are inverted and maintained, respectively, which is similar to the documented results (Berrang & Hortor, 1970; Bethel & Ferrier, 1972), but disagrees with the molecular structure reported by Divjaković (Divjakovic et al., 1992). Both the molecular conformation and structure are consistent with our desired intermediates for the synthesis of the corresponding 2',3'-dideoxy-2',3'-dimercaptoribonucleosides.

Related literature top

For the bioactiviy of nucleosides, see: Zhang et al. (2007); Merino et al. (2008). For the structure of the precursro, 3,5,6-tri-O-acetyl-1,2-O-isopropylidene-α-D-glucofuranose, see: Wu et al. (2009). For related structures, see: Bethel & Ferrier (1972); Berrang & Hortor (1970); Divjaković et al. (1992).

Experimental top

ZnBr₂ (0.54 g, 2.4 mmol) was added to a solution of 3,5,6-tri-O-acetyl-1,2-O-isopropylidene-α-D-glucofuranose (0.67 g, 2.0 mmol) and ethanethiol (0.78 ml, 10 mmol) in dry CH₂Cl₂ (10 ml). After 5 h, saturated aqueous solution of NaHCO₃ (20 ml) was added and separated. The organic layer was washed with brine, dried with MgSO₄ and concentrated under reduced pressure. The residue was isolated through short column chromatography on silica gel, which was eluded with EtOAc-petroleum to give the target compound (0.78 g, 78%). M. p. 62°, ¹H-NMR(CDCl₃, p.p.m.): 1.28 (m, 12 H), 2.06 (m, 9 H), 2.75 (m, 8 H), 3.07 (dd, 1 H), 3.48 (dd, 1 H), 4.20 (m, 1 H), 4.49 (dd, 1 H), 4.6 4 (d, 1 H), 5.54 (m, 1 H), 5.89 (dd, 1 H); ¹³C-NMR(CDCl₃, p.p.m.):14.60, 14.74, 14.85, 14.92, 15.02, 21.23, 21.27, 25.79, 26.39, 28.31, 30.24, 51.47, 57.30, 57.48, 62.56, 71.96, 72.78, 169.19, 169.61, 170.82; HRMS (EI) m/z calculated for C₂₀H₃₆O₆S₄ 500.13, found 500.14.

50 mg of the obtained product was dissolved in petroleum ether (5 ml) and the solution was kept at room temperature for 2 days to give colorless single crystals.

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2005); cell refinement: CrystalClear (Rigaku/MSC, 2005); data reduction: CrystalClear (Rigaku/MSC, 2005); 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. Molecular structure of the title compound with thermal displacement ellipsoids drawn at the 30% probability level. Open bonds show the disorder component.

4,5,6-Tri-O-acetyl-2,3-di-S-ethyl-2,3-dithio-D-allose diethyl dithioacetal top

Crystal data top

C₂₀H₃₆O₆S₄	F(000) = 536
M_r = 500.73	D_x = 1.302 Mg m⁻³
Monoclinic, P2₁	Mo Kα radiation, λ = 0.71070 Å
Hall symbol: P 2yb	Cell parameters from 4760 reflections
a = 8.3395 (12) Å	θ = 2.2–27.9°
b = 16.726 (2) Å	µ = 0.40 mm⁻¹
c = 9.2027 (14) Å	T = 113 K
β = 95.772 (5)°	Block, colorless
V = 1277.2 (3) Å³	0.26 × 0.20 × 0.18 mm
Z = 2

Data collection top

Rigaku Saturn diffractometer	6060 independent reflections
Radiation source: rotating anode	5802 reflections with I > 2σ(I)
Confocal monochromator	R_int = 0.032
Detector resolution: 14.63 pixels mm^-1	θ_max = 27.9°, θ_min = 2.2°
ω scans	h = −10→10
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005)	k = −21→22
T_min = 0.902, T_max = 0.931	l = −12→12
16052 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)] = 0.032	H-atom parameters constrained
wR(F²) = 0.066	w = 1/[σ²(F_o²) + (0.0326P)²] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max = 0.001
6060 reflections	Δρ_max = 0.20 e Å⁻³
298 parameters	Δρ_min = −0.29 e Å⁻³
23 restraints	Absolute structure: Flack (1983), 2919 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.03 (4)

Crystal data top

C₂₀H₃₆O₆S₄	V = 1277.2 (3) Å³
M_r = 500.73	Z = 2
Monoclinic, P2₁	Mo Kα radiation
a = 8.3395 (12) Å	µ = 0.40 mm⁻¹
b = 16.726 (2) Å	T = 113 K
c = 9.2027 (14) Å	0.26 × 0.20 × 0.18 mm
β = 95.772 (5)°

Data collection top

Rigaku Saturn diffractometer	6060 independent reflections
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005)	5802 reflections with I > 2σ(I)
T_min = 0.902, T_max = 0.931	R_int = 0.032
16052 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.032	H-atom parameters constrained
wR(F²) = 0.066	Δρ_max = 0.20 e Å⁻³
S = 1.04	Δρ_min = −0.29 e Å⁻³
6060 reflections	Absolute structure: Flack (1983), 2919 Friedel pairs
298 parameters	Absolute structure parameter: −0.03 (4)
23 restraints

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	Occ. (<1)
S1	0.74081 (5)	−0.08494 (3)	0.79166 (5)	0.02103 (10)
S2	0.70511 (5)	0.08746 (3)	0.88989 (5)	0.02203 (10)
S3	0.41930 (5)	0.00547 (3)	0.66199 (5)	0.01940 (10)
S4	0.85901 (5)	0.02564 (3)	0.42590 (5)	0.02148 (10)
O1	0.56270 (15)	−0.06561 (7)	0.23706 (13)	0.0182 (3)
O2	0.32000 (18)	−0.12020 (10)	0.25917 (18)	0.0405 (4)
O3	0.54225 (14)	0.14186 (7)	0.33931 (12)	0.0169 (3)
O4	0.68402 (15)	0.21225 (8)	0.18563 (14)	0.0269 (3)
O5	0.25647 (13)	0.10093 (8)	0.19236 (13)	0.0209 (3)
O6	0.26208 (18)	0.22570 (8)	0.10243 (18)	0.0378 (4)
C1	0.74322 (19)	0.02080 (11)	0.74033 (17)	0.0171 (3)
H1	0.8521	0.0336	0.7099	0.021*
C2	0.61765 (18)	0.03465 (11)	0.60845 (18)	0.0156 (3)
H2	0.6143	0.0933	0.5873	0.019*
C3	0.66042 (18)	−0.00888 (10)	0.46908 (17)	0.0147 (3)
H3	0.6708	−0.0670	0.4933	0.018*
C4	0.53286 (19)	−0.00125 (11)	0.33657 (17)	0.0148 (3)
H4	0.4224	−0.0068	0.3689	0.018*
C5	0.5413 (2)	0.07353 (10)	0.24304 (18)	0.0164 (4)
H5	0.6440	0.0727	0.1957	0.020*
C6	0.3999 (2)	0.08169 (12)	0.12490 (18)	0.0202 (4)
H6A	0.4227	0.1244	0.0554	0.024*
H6B	0.3843	0.0309	0.0700	0.024*
C7	0.8968 (2)	−0.08772 (14)	0.94224 (19)	0.0284 (4)
H7A	0.8763	−0.0444	1.0112	0.034*
H7B	0.8888	−0.1391	0.9944	0.034*
C8	1.0684 (2)	−0.07889 (15)	0.9010 (3)	0.0398 (5)
H8A	1.0926	−0.1230	0.8366	0.060*
H8B	1.1441	−0.0801	0.9896	0.060*
H8C	1.0788	−0.0279	0.8503	0.060*
C9	0.8906 (2)	0.14400 (14)	0.9124 (2)	0.0311 (5)
H9A	0.8924	0.1759	1.0031	0.037*
H9B	0.9821	0.1061	0.9247	0.037*
C10	0.9154 (3)	0.19954 (14)	0.7876 (3)	0.0395 (5)
H10A	0.9222	0.1683	0.6984	0.059*
H10B	1.0155	0.2297	0.8104	0.059*
H10C	0.8245	0.2368	0.7729	0.059*
C11	0.2932 (2)	0.08823 (13)	0.59307 (19)	0.0237 (4)
H11A	0.3106	0.0975	0.4896	0.028*
H11B	0.1789	0.0730	0.5962	0.028*
C12	0.3242 (2)	0.16570 (13)	0.6765 (2)	0.0302 (5)
H12A	0.2985	0.1585	0.7773	0.045*
H12B	0.2561	0.2080	0.6296	0.045*
H12C	0.4378	0.1806	0.6766	0.045*
C13	0.9482 (3)	−0.06248 (16)	0.3541 (3)	0.0317 (8)	0.869 (6)
H13A	0.8677	−0.0883	0.2826	0.038*	0.869 (6)
H13B	1.0406	−0.0461	0.3013	0.038*	0.869 (6)
C14	1.0059 (4)	−0.1230 (2)	0.4699 (3)	0.0428 (9)	0.869 (6)
H14A	1.0905	−0.0991	0.5378	0.064*	0.869 (6)
H14B	1.0490	−0.1700	0.4233	0.064*	0.869 (6)
H14C	0.9154	−0.1392	0.5235	0.064*	0.869 (6)
C13'	0.9867 (15)	−0.0625 (8)	0.4615 (17)	0.024 (5)	0.131 (6)
H13C	1.0967	−0.0488	0.4379	0.029*	0.131 (6)
H13D	0.9937	−0.0741	0.5674	0.029*	0.131 (6)
C14'	0.935 (2)	−0.1377 (8)	0.381 (2)	0.036 (4)	0.131 (6)
H14D	0.8573	−0.1665	0.4339	0.054*	0.131 (6)
H14E	1.0297	−0.1717	0.3722	0.054*	0.131 (6)
H14F	0.8855	−0.1240	0.2827	0.054*	0.131 (6)
C15	0.4443 (2)	−0.12014 (11)	0.20382 (19)	0.0200 (4)
C16	0.4899 (3)	−0.17588 (12)	0.0885 (2)	0.0277 (4)
H16A	0.4155	−0.2214	0.0805	0.042*
H16B	0.6000	−0.1952	0.1143	0.042*
H16C	0.4843	−0.1477	−0.0053	0.042*
C17	0.6157 (2)	0.20907 (11)	0.2941 (2)	0.0209 (4)
C18	0.5959 (3)	0.27634 (12)	0.3979 (2)	0.0326 (5)
H18A	0.6485	0.3244	0.3644	0.049*
H18B	0.6454	0.2617	0.4954	0.049*
H18C	0.4810	0.2871	0.4021	0.049*
C19	0.2065 (2)	0.17773 (11)	0.1783 (2)	0.0221 (4)
C20	0.0766 (2)	0.19526 (13)	0.2743 (2)	0.0301 (5)
H20A	0.1246	0.2033	0.3748	0.045*
H20B	0.0012	0.1502	0.2712	0.045*
H20C	0.0187	0.2437	0.2397	0.045*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0232 (2)	0.0209 (2)	0.0183 (2)	−0.00083 (19)	−0.00179 (18)	0.00364 (18)
S2	0.0236 (2)	0.0275 (2)	0.0155 (2)	−0.00207 (19)	0.00384 (17)	−0.00323 (19)
S3	0.0155 (2)	0.0251 (2)	0.0183 (2)	−0.00173 (18)	0.00489 (16)	0.00091 (18)
S4	0.01363 (19)	0.0294 (3)	0.0218 (2)	−0.00129 (18)	0.00362 (16)	0.00257 (19)
O1	0.0183 (6)	0.0201 (7)	0.0166 (6)	−0.0007 (5)	0.0034 (5)	−0.0072 (5)
O2	0.0312 (8)	0.0411 (9)	0.0523 (10)	−0.0176 (7)	0.0194 (7)	−0.0234 (8)
O3	0.0213 (6)	0.0138 (6)	0.0157 (6)	−0.0013 (5)	0.0026 (5)	0.0002 (5)
O4	0.0221 (7)	0.0292 (8)	0.0298 (7)	−0.0023 (6)	0.0050 (6)	0.0102 (6)
O5	0.0175 (6)	0.0194 (7)	0.0253 (7)	0.0012 (5)	−0.0005 (5)	0.0021 (5)
O6	0.0368 (8)	0.0244 (8)	0.0556 (10)	0.0038 (6)	0.0209 (8)	0.0118 (7)
C1	0.0174 (8)	0.0212 (9)	0.0128 (8)	−0.0003 (7)	0.0018 (6)	−0.0010 (7)
C2	0.0128 (8)	0.0171 (8)	0.0167 (8)	−0.0016 (7)	0.0006 (6)	−0.0001 (6)
C3	0.0146 (8)	0.0165 (9)	0.0133 (8)	0.0000 (7)	0.0028 (6)	0.0000 (7)
C4	0.0153 (8)	0.0159 (8)	0.0132 (8)	0.0026 (7)	0.0009 (6)	−0.0056 (7)
C5	0.0152 (8)	0.0166 (9)	0.0172 (9)	0.0016 (7)	0.0016 (6)	−0.0023 (7)
C6	0.0209 (9)	0.0257 (10)	0.0138 (8)	0.0023 (8)	0.0011 (7)	−0.0024 (7)
C7	0.0352 (10)	0.0305 (11)	0.0176 (9)	0.0017 (9)	−0.0064 (8)	0.0041 (9)
C8	0.0276 (11)	0.0400 (13)	0.0482 (14)	0.0029 (10)	−0.0139 (9)	0.0012 (11)
C9	0.0263 (10)	0.0344 (12)	0.0317 (11)	−0.0028 (9)	−0.0008 (8)	−0.0138 (9)
C10	0.0338 (11)	0.0283 (12)	0.0586 (15)	−0.0064 (10)	0.0160 (11)	−0.0079 (11)
C11	0.0174 (8)	0.0356 (11)	0.0182 (9)	0.0039 (8)	0.0029 (7)	0.0010 (9)
C12	0.0293 (11)	0.0346 (12)	0.0271 (11)	0.0066 (9)	0.0041 (8)	−0.0036 (9)
C13	0.0213 (12)	0.0515 (18)	0.0234 (15)	0.0072 (11)	0.0073 (10)	−0.0077 (11)
C14	0.0442 (17)	0.046 (2)	0.0393 (18)	0.0195 (14)	0.0118 (13)	−0.0025 (14)
C13'	0.007 (7)	0.045 (12)	0.022 (10)	−0.005 (6)	0.004 (6)	0.002 (7)
C14'	0.032 (7)	0.024 (7)	0.050 (8)	0.010 (6)	−0.009 (6)	−0.005 (6)
C15	0.0265 (10)	0.0197 (9)	0.0138 (9)	−0.0023 (8)	0.0025 (7)	−0.0008 (7)
C16	0.0377 (11)	0.0240 (10)	0.0222 (10)	−0.0048 (9)	0.0067 (8)	−0.0076 (8)
C17	0.0155 (8)	0.0178 (9)	0.0281 (10)	0.0003 (7)	−0.0037 (7)	0.0074 (8)
C18	0.0386 (12)	0.0200 (10)	0.0382 (13)	−0.0062 (9)	−0.0003 (10)	−0.0018 (8)
C19	0.0166 (8)	0.0230 (10)	0.0253 (10)	0.0003 (8)	−0.0043 (7)	0.0008 (8)
C20	0.0242 (10)	0.0332 (12)	0.0329 (12)	0.0057 (9)	0.0033 (8)	0.0084 (9)

Geometric parameters (Å, º) top

S1—C7	1.8035 (18)	C9—C10	1.507 (3)
S1—C1	1.8313 (19)	C9—H9A	0.9900
S2—C9	1.807 (2)	C9—H9B	0.9900
S2—C1	1.8238 (17)	C10—H10A	0.9800
S3—C11	1.814 (2)	C10—H10B	0.9800
S3—C2	1.8387 (16)	C10—H10C	0.9800
S4—C13	1.806 (2)	C11—C12	1.515 (3)
S4—C13'	1.829 (13)	C11—H11A	0.9900
S4—C3	1.8348 (16)	C11—H11B	0.9900
O1—C15	1.357 (2)	C12—H12A	0.9800
O1—C4	1.4510 (19)	C12—H12B	0.9800
O2—C15	1.200 (2)	C12—H12C	0.9800
O3—C17	1.365 (2)	C13—C14	1.513 (4)
O3—C5	1.446 (2)	C13—H13A	0.9900
O4—C17	1.199 (2)	C13—H13B	0.9900
O5—C19	1.352 (2)	C14—H14A	0.9800
O5—C6	1.439 (2)	C14—H14B	0.9800
O6—C19	1.188 (2)	C14—H14C	0.9800
C1—C2	1.539 (2)	C13'—C14'	1.502 (19)
C1—H1	1.0000	C13'—H13C	0.9900
C2—C3	1.547 (2)	C13'—H13D	0.9900
C2—H2	1.0000	C14'—H14D	0.9800
C3—C4	1.541 (2)	C14'—H14E	0.9800
C3—H3	1.0000	C14'—H14F	0.9800
C4—C5	1.524 (2)	C15—C16	1.491 (2)
C4—H4	1.0000	C16—H16A	0.9800
C5—C6	1.527 (2)	C16—H16B	0.9800
C5—H5	1.0000	C16—H16C	0.9800
C6—H6A	0.9900	C17—C18	1.496 (3)
C6—H6B	0.9900	C18—H18A	0.9800
C7—C8	1.524 (3)	C18—H18B	0.9800
C7—H7A	0.9900	C18—H18C	0.9800
C7—H7B	0.9900	C19—C20	1.495 (3)
C8—H8A	0.9800	C20—H20A	0.9800
C8—H8B	0.9800	C20—H20B	0.9800
C8—H8C	0.9800	C20—H20C	0.9800

C7—S1—C1	101.38 (9)	C9—C10—H10A	109.5
C9—S2—C1	101.20 (9)	C9—C10—H10B	109.5
C11—S3—C2	102.08 (8)	H10A—C10—H10B	109.5
C13—S4—C13'	32.2 (5)	C9—C10—H10C	109.5
C13—S4—C3	103.66 (10)	H10A—C10—H10C	109.5
C13'—S4—C3	103.3 (4)	H10B—C10—H10C	109.5
C15—O1—C4	118.30 (13)	C12—C11—S3	114.35 (13)
C17—O3—C5	116.06 (13)	C12—C11—H11A	108.7
C19—O5—C6	115.63 (14)	S3—C11—H11A	108.7
C2—C1—S2	110.29 (11)	C12—C11—H11B	108.7
C2—C1—S1	108.94 (11)	S3—C11—H11B	108.7
S2—C1—S1	112.86 (9)	H11A—C11—H11B	107.6
C2—C1—H1	108.2	C11—C12—H12A	109.5
S2—C1—H1	108.2	C11—C12—H12B	109.5
S1—C1—H1	108.2	H12A—C12—H12B	109.5
C1—C2—C3	112.81 (13)	C11—C12—H12C	109.5
C1—C2—S3	107.93 (11)	H12A—C12—H12C	109.5
C3—C2—S3	112.69 (11)	H12B—C12—H12C	109.5
C1—C2—H2	107.7	C14—C13—S4	113.70 (19)
C3—C2—H2	107.7	C14—C13—H13A	108.8
S3—C2—H2	107.7	S4—C13—H13A	108.8
C4—C3—C2	114.75 (13)	C14—C13—H13B	108.8
C4—C3—S4	111.65 (11)	S4—C13—H13B	108.8
C2—C3—S4	108.65 (11)	H13A—C13—H13B	107.7
C4—C3—H3	107.1	C14'—C13'—S4	117.0 (11)
C2—C3—H3	107.1	C14'—C13'—H13C	108.0
S4—C3—H3	107.1	S4—C13'—H13C	108.0
O1—C4—C5	103.41 (12)	C14'—C13'—H13D	108.0
O1—C4—C3	106.83 (13)	S4—C13'—H13D	108.0
C5—C4—C3	116.60 (14)	H13C—C13'—H13D	107.3
O1—C4—H4	109.9	C13'—C14'—H14D	109.5
C5—C4—H4	109.9	C13'—C14'—H14E	109.5
C3—C4—H4	109.9	H14D—C14'—H14E	109.5
O3—C5—C4	107.49 (13)	C13'—C14'—H14F	109.5
O3—C5—C6	108.79 (13)	H14D—C14'—H14F	109.5
C4—C5—C6	113.55 (14)	H14E—C14'—H14F	109.5
O3—C5—H5	109.0	O2—C15—O1	123.03 (17)
C4—C5—H5	109.0	O2—C15—C16	126.52 (18)
C6—C5—H5	109.0	O1—C15—C16	110.42 (15)
O5—C6—C5	109.18 (13)	C15—C16—H16A	109.5
O5—C6—H6A	109.8	C15—C16—H16B	109.5
C5—C6—H6A	109.8	H16A—C16—H16B	109.5
O5—C6—H6B	109.8	C15—C16—H16C	109.5
C5—C6—H6B	109.8	H16A—C16—H16C	109.5
H6A—C6—H6B	108.3	H16B—C16—H16C	109.5
C8—C7—S1	115.40 (14)	O4—C17—O3	123.77 (18)
C8—C7—H7A	108.4	O4—C17—C18	126.18 (18)
S1—C7—H7A	108.4	O3—C17—C18	110.05 (15)
C8—C7—H7B	108.4	C17—C18—H18A	109.5
S1—C7—H7B	108.4	C17—C18—H18B	109.5
H7A—C7—H7B	107.5	H18A—C18—H18B	109.5
C7—C8—H8A	109.5	C17—C18—H18C	109.5
C7—C8—H8B	109.5	H18A—C18—H18C	109.5
H8A—C8—H8B	109.5	H18B—C18—H18C	109.5
C7—C8—H8C	109.5	O6—C19—O5	124.29 (17)
H8A—C8—H8C	109.5	O6—C19—C20	124.31 (18)
H8B—C8—H8C	109.5	O5—C19—C20	111.37 (16)
C10—C9—S2	114.64 (15)	C19—C20—H20A	109.5
C10—C9—H9A	108.6	C19—C20—H20B	109.5
S2—C9—H9A	108.6	H20A—C20—H20B	109.5
C10—C9—H9B	108.6	C19—C20—H20C	109.5
S2—C9—H9B	108.6	H20A—C20—H20C	109.5
H9A—C9—H9B	107.6	H20B—C20—H20C	109.5

C9—S2—C1—C2	−119.35 (13)	S4—C3—C4—C5	−39.69 (17)
C9—S2—C1—S1	118.55 (11)	C17—O3—C5—C4	153.04 (14)
C7—S1—C1—C2	178.77 (11)	C17—O3—C5—C6	−83.62 (17)
C7—S1—C1—S2	−58.37 (11)	O1—C4—C5—O3	−169.73 (12)
S2—C1—C2—C3	169.79 (11)	C3—C4—C5—O3	−52.85 (18)
S1—C1—C2—C3	−65.83 (15)	O1—C4—C5—C6	69.89 (16)
S2—C1—C2—S3	−65.04 (13)	C3—C4—C5—C6	−173.23 (13)
S1—C1—C2—S3	59.34 (13)	C19—O5—C6—C5	104.90 (17)
C11—S3—C2—C1	134.39 (12)	O3—C5—C6—O5	−48.42 (19)
C11—S3—C2—C3	−100.37 (12)	C4—C5—C6—O5	71.22 (18)
C1—C2—C3—C4	176.29 (14)	C1—S1—C7—C8	−71.74 (18)
S3—C2—C3—C4	53.74 (17)	C1—S2—C9—C10	68.51 (17)
C1—C2—C3—S4	−57.96 (16)	C2—S3—C11—C12	−71.05 (15)
S3—C2—C3—S4	179.49 (9)	C13'—S4—C13—C14	18.1 (8)
C13—S4—C3—C4	−87.95 (15)	C3—S4—C13—C14	−75.1 (2)
C13'—S4—C3—C4	−121.1 (5)	C13—S4—C13'—C14'	−38.2 (11)
C13—S4—C3—C2	144.51 (13)	C3—S4—C13'—C14'	56.4 (13)
C13'—S4—C3—C2	111.4 (5)	C4—O1—C15—O2	−4.4 (3)
C15—O1—C4—C5	−116.96 (15)	C4—O1—C15—C16	173.80 (15)
C15—O1—C4—C3	119.46 (15)	C5—O3—C17—O4	−3.9 (2)
C2—C3—C4—O1	−160.52 (13)	C5—O3—C17—C18	175.50 (14)
S4—C3—C4—O1	75.30 (15)	C6—O5—C19—O6	8.6 (3)
C2—C3—C4—C5	84.49 (17)	C6—O5—C19—C20	−169.42 (14)

Experimental details

Crystal data
Chemical formula	C₂₀H₃₆O₆S₄
M_r	500.73
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	113
a, b, c (Å)	8.3395 (12), 16.726 (2), 9.2027 (14)
β (°)	95.772 (5)
V (Å³)	1277.2 (3)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.40
Crystal size (mm)	0.26 × 0.20 × 0.18

Data collection
Diffractometer	Rigaku Saturn diffractometer
Absorption correction	Multi-scan (CrystalClear; Rigaku/MSC, 2005)
T_min, T_max	0.902, 0.931
No. of measured, independent and observed [I > 2σ(I)] reflections	16052, 6060, 5802
R_int	0.032
(sin θ/λ)_max (Å⁻¹)	0.658

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.032, 0.066, 1.04
No. of reflections	6060
No. of parameters	298
No. of restraints	23
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.20, −0.29
Absolute structure	Flack (1983), 2919 Friedel pairs
Absolute structure parameter	−0.03 (4)

Computer programs: CrystalClear (Rigaku/MSC, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

The authors thank the National Science Foundation of China (30340070) and the Ministry of Science and Technology of China (2006 A A100216) for financial support.

References

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