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Acta Crystallogr Sect E Struct Rep Online. 2008 August 1; 64(Pt 8): o1558.
Published online 2008 July 19. doi:  10.1107/S1600536808022253
PMCID: PMC2962180

1-(2,3-Di-O-acetyl-4-chloro-4-de­oxy-6-O-tosyl-β-d-galactopyranos­yl)propan-2-one methanol 0.25-solvate

Abstract

The asymmetric unit of the title solvate, C20H25ClO9S·0.25CH3OH, contains one galactopyranosyl derivative and one-quarter of a methanol solvent mol­ecule. The galactopyran­ose ring is in the usual 4 C 1 conformation, and the anomeric center of the sugar has a β configuration. The value of θ (3.44°) and the range of torsion angles [or 53.1 (5)–63.0 (5)°] reflect a slight distortion of the 4 C 1 pyran­ose ring. A minor orientational disorder affects a carbonyl group, which was modeled with two sites for the O atom having occupancies of 0.79 (5) and 0.21 (5). The crystal studied exhibited inversion twinning.

Related literature

For related literature, see: Lewis et al. (1982 [triangle]); Nicolaou et al. (1995 [triangle]); Paterson & Mansuri (1985 [triangle]); Postema (1992 [triangle]); Tvaroška et al. (2002 [triangle]).

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Object name is e-64-o1558-scheme1.jpg

Experimental

Crystal data

  • C20H25ClO9S·0.25CH4O
  • M r = 484.92
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-64-o1558-efi1.jpg
  • a = 7.3300 (15) Å
  • b = 14.608 (3) Å
  • c = 22.329 (5) Å
  • V = 2390.9 (8) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.29 mm−1
  • T = 291 (2) K
  • 0.20 × 0.17 × 0.16 mm

Data collection

  • Bruker SMART APEX CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2001 [triangle]) T min = 0.944, T max = 0.954
  • 7242 measured reflections
  • 4129 independent reflections
  • 3274 reflections with I > 2σ(I)
  • R int = 0.052

Refinement

  • R[F 2 > 2σ(F 2)] = 0.061
  • wR(F 2) = 0.154
  • S = 1.00
  • 4129 reflections
  • 304 parameters
  • 2 restraints
  • H-atom parameters constrained
  • Δρmax = 0.19 e Å−3
  • Δρmin = −0.29 e Å−3
  • Absolute structure: Flack (1983 [triangle]), 1683 Friedel pairs
  • Flack parameter: 0.42 (11)

Data collection: SMART (Bruker, 2001 [triangle]); cell refinement: SAINT-Plus (Bruker, 2001 [triangle]); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXL97; software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808022253/bh2169sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808022253/bh2169Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

This work was financially supported by the NNSF of the People’s Republic of China (No. 20572103).

supplementary crystallographic information

Comment

Due to their unique chemical and enzymatic hydrolysis stability, C-glycosides are becoming useful building blocks (Postema, 1992) for the total synthesis of various types of natural products such as palytoxin (Lewis et al., 1982), brevetoxin (Nicolaou et al., 1995) and polyether antibiotics (Paterson & Mansuri, 1985), and are used as a model in enzymatic and metabolic studies as well. Despite this attractive applications, structural investigations by using single-crystal X-ray analysis, which provides unambiguous structural data, are rare. Herein we report the design and synthesis of an acylated C-glycosidic analog, which would be of great interest in order to get additional crystallographic information about the substrate.

In the orthorhombic crystals of the title compound, the asymmetric unit contains one molecule and 0.25 methanol solvate. No significant hydrogen bonds exist in the crystal. The value of θ (3.44°) and the magnitude of the torsion angles in the ring (52.9–63.6°) reveal that the 4C1 pyranose ring presents a slight distortion. The primary hydroxyl group in the title compound is in the gt position [O1—C5—C6—O7 = 74.9 (5)°], which is known to be the favored orientation for pyranose with the galacto configuration (Tvaroška et al., 2002).

Experimental

All reagents were commercially available and of analytical grade. Sulfonylation of 1-(4-chloro-4-deoxy-β-D-galactopyranosyl)-propan-2-one with toluene-4-sulfonyl chloride in dry pyridine afforded the 6-toluenesulfonylated intermediate. Further acetylation with acetyl anhydride in pyridine and subsequent purification by chromatography on silica gel furnished the title compound as a white solid. White crystals suitable for X-ray crystallographic analysis were obtained by recrystallization from methanol.

Refinement

All H atoms bonded to C atoms were positioned geometrically and refined as riding to their parent atoms, with C—H = 0.93–0.98 Å and Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C). For the methanol molecule, the hydroxyl H atom was positioned geometrically and refined as riding with O—H = 0.82Å and Uiso(H) = 1.5Ueq(O). Assuming that starting material is enantiomerically pure, and that anomalous dispersion effects from S and Cl atoms are significant, we suppose that the refined Flack parameter, 0.42 (11) based on 1683 measured Friedel pairs, reflects a partial twinning by merohedry for the sample used for data collection.

Figures

Fig. 1.
The molecular structure of (I), showing atom displacement ellipsoids drawn at the 50% probability level.

Crystal data

C20H25ClO9S·0.25CH4OF000 = 1018
Mr = 484.92Dx = 1.347 Mg m3
Orthorhombic, P212121Mo Kα radiation λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 399 reflections
a = 7.3300 (15) Åθ = 2–25.1º
b = 14.608 (3) ŵ = 0.29 mm1
c = 22.329 (5) ÅT = 291 (2) K
V = 2390.9 (8) Å3Prism, colourless
Z = 40.20 × 0.17 × 0.16 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer4129 independent reflections
Radiation source: fine-focus sealed tube3274 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.052
T = 291(2) Kθmax = 25.3º
0.3° wide ω scansθmin = 1.7º
Absorption correction: multi-scan(SADABS; Bruker, 2001)h = −8→8
Tmin = 0.944, Tmax = 0.954k = −17→17
7242 measured reflectionsl = −26→26

Refinement

Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.062  w = 1/[σ2(Fo2) + (0.0873P)2 + 0.6536P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.154(Δ/σ)max < 0.001
S = 1.00Δρmax = 0.19 e Å3
4129 reflectionsΔρmin = −0.29 e Å3
304 parametersExtinction correction: none
2 restraintsAbsolute structure: Flack (1983), 1683 Friedel pairs
Primary atom site location: structure-invariant direct methodsFlack parameter: 0.42 (11)
Secondary atom site location: difference Fourier map

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

xyzUiso*/UeqOcc. (<1)
S10.32977 (15)0.92085 (8)0.03975 (5)0.0411 (3)
Cl10.65974 (18)1.05079 (11)0.24709 (5)0.0662 (4)
O10.7356 (4)1.1010 (2)0.11261 (14)0.0425 (7)
O20.8839 (8)1.1761 (3)−0.01365 (18)0.0918 (16)
O31.1793 (4)1.1764 (2)0.16930 (14)0.0481 (8)
O41.113 (5)1.3083 (19)0.2077 (18)0.054 (11)0.21 (5)
O4'1.132 (2)1.2846 (17)0.2385 (15)0.137 (9)0.79 (5)
O51.0691 (4)1.0491 (2)0.25895 (13)0.0512 (8)
O61.2341 (6)0.9227 (3)0.2414 (2)0.0779 (12)
O70.5241 (4)0.9533 (2)0.06115 (13)0.0453 (8)
O80.3338 (5)0.9324 (2)−0.02346 (13)0.0599 (9)
O90.1958 (4)0.9671 (2)0.07483 (15)0.0507 (8)
O101.184 (7)1.295 (3)0.3532 (19)0.205 (15)*0.25
H101.11331.29160.32500.308*0.25
C10.9128 (6)1.1430 (3)0.1106 (2)0.0389 (10)
H1A0.99241.10710.08430.047*
C20.9930 (6)1.1440 (3)0.17380 (19)0.0384 (10)
H2A0.92111.18340.20030.046*
C31.0018 (6)1.0463 (3)0.19808 (18)0.0400 (10)
H3A1.08801.01120.17360.048*
C40.8168 (7)1.0005 (3)0.19472 (19)0.0425 (10)
H4A0.83160.93560.20470.051*
C50.7433 (7)1.0076 (3)0.1312 (2)0.0423 (11)
H5A0.82570.97450.10430.051*
C60.5551 (7)0.9680 (4)0.1250 (2)0.0528 (13)
H6A0.54640.91050.14660.063*
H6B0.46491.01000.14100.063*
C70.8895 (7)1.2381 (3)0.0847 (2)0.0525 (12)
H7A0.99111.27570.09790.063*
H7B0.77901.26470.10120.063*
C80.8787 (7)1.2427 (4)0.0170 (2)0.0544 (13)
C90.8655 (10)1.3370 (4)−0.0087 (3)0.0760 (18)
H9A0.85241.3331−0.05140.114*
H9B0.97421.37060.00080.114*
H9C0.76151.36770.00800.114*
C101.2286 (8)1.2513 (4)0.1997 (4)0.0768 (19)
C111.4220 (9)1.2763 (5)0.1873 (4)0.101 (3)
H11A1.44641.33630.20290.152*
H11B1.44301.27590.14490.152*
H11C1.50141.23270.20630.152*
C121.1872 (7)0.9807 (4)0.2751 (2)0.0527 (12)
C131.2456 (10)0.9929 (6)0.3384 (3)0.093 (2)
H13A1.35390.95770.34570.139*
H13B1.15020.97260.36470.139*
H13C1.27051.05650.34580.139*
C140.3198 (6)0.8038 (3)0.05653 (18)0.0417 (10)
C150.2354 (7)0.7735 (3)0.1088 (2)0.0492 (12)
H15A0.19120.81510.13680.059*
C160.2191 (8)0.6808 (3)0.1182 (2)0.0557 (13)
H16A0.16280.66050.15310.067*
C170.2823 (7)0.6174 (3)0.0783 (2)0.0524 (13)
C180.3687 (7)0.6498 (4)0.0270 (3)0.0593 (14)
H18A0.41580.6077−0.00020.071*
C190.3868 (7)0.7414 (4)0.0151 (2)0.0547 (13)
H19A0.44290.7613−0.01990.066*
C200.2580 (10)0.5161 (4)0.0872 (3)0.0769 (18)
H20A0.23530.50370.12880.115*
H20B0.36660.48470.07480.115*
H20D0.15650.49520.06370.115*
C211.292 (6)1.229 (3)0.3514 (17)0.135 (14)*0.25
H21A1.27691.19240.38660.202*0.25
H21B1.41491.25180.34960.202*0.25
H21C1.26721.19300.31640.202*0.25

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
S10.0419 (6)0.0444 (6)0.0369 (5)−0.0053 (5)−0.0003 (5)−0.0019 (5)
Cl10.0561 (7)0.1008 (11)0.0417 (6)−0.0185 (8)0.0082 (6)−0.0121 (6)
O10.0387 (16)0.0413 (18)0.0476 (18)−0.0039 (13)−0.0022 (14)0.0046 (14)
O20.167 (5)0.053 (2)0.055 (2)−0.008 (3)−0.020 (3)0.002 (2)
O30.0376 (16)0.0496 (18)0.0570 (19)−0.0041 (16)0.0007 (15)−0.0052 (15)
O40.062 (14)0.026 (14)0.07 (2)−0.006 (9)−0.013 (12)−0.011 (12)
O4'0.086 (6)0.121 (12)0.20 (2)−0.026 (7)0.017 (10)−0.107 (14)
O50.0522 (18)0.065 (2)0.0363 (18)0.0044 (17)−0.0092 (14)−0.0027 (16)
O60.078 (3)0.083 (3)0.073 (3)0.026 (2)−0.012 (2)−0.003 (2)
O70.0475 (17)0.057 (2)0.0314 (16)−0.0150 (16)0.0000 (13)−0.0044 (15)
O80.069 (2)0.075 (2)0.0353 (17)−0.013 (2)−0.0064 (16)0.0054 (15)
O90.0485 (18)0.0431 (18)0.060 (2)0.0050 (15)0.0037 (16)−0.0022 (15)
C10.041 (2)0.032 (2)0.044 (3)−0.0023 (19)0.0048 (19)0.005 (2)
C20.035 (2)0.042 (3)0.039 (2)0.0004 (19)0.0023 (18)−0.002 (2)
C30.044 (2)0.046 (3)0.030 (2)0.000 (2)0.0017 (18)−0.002 (2)
C40.051 (3)0.037 (2)0.039 (2)−0.006 (2)0.002 (2)−0.0006 (18)
C50.046 (3)0.043 (3)0.037 (2)−0.006 (2)0.0000 (19)0.0007 (19)
C60.055 (3)0.061 (3)0.042 (3)−0.024 (3)0.002 (2)−0.004 (2)
C70.058 (3)0.043 (3)0.056 (3)−0.001 (2)0.000 (2)−0.002 (2)
C80.056 (3)0.045 (3)0.062 (3)−0.008 (2)−0.009 (2)0.014 (3)
C90.089 (4)0.054 (3)0.085 (4)0.001 (3)−0.020 (4)0.027 (3)
C100.051 (3)0.054 (4)0.125 (6)−0.007 (3)−0.004 (4)−0.033 (4)
C110.060 (4)0.079 (5)0.166 (8)−0.026 (3)−0.006 (4)−0.015 (5)
C120.040 (3)0.069 (3)0.049 (3)0.004 (3)−0.003 (2)0.012 (3)
C130.089 (5)0.139 (6)0.050 (3)0.041 (5)−0.013 (3)0.006 (4)
C140.037 (2)0.048 (2)0.040 (2)−0.006 (2)−0.001 (2)−0.0071 (19)
C150.061 (3)0.047 (3)0.040 (3)0.000 (2)−0.001 (2)−0.004 (2)
C160.077 (4)0.044 (3)0.046 (3)−0.002 (2)−0.004 (3)0.000 (2)
C170.056 (3)0.043 (3)0.059 (3)0.001 (2)−0.021 (3)−0.006 (2)
C180.048 (3)0.052 (3)0.077 (4)0.008 (2)0.000 (3)−0.030 (3)
C190.051 (3)0.055 (3)0.059 (3)−0.004 (2)0.010 (2)−0.019 (3)
C200.090 (4)0.041 (3)0.099 (5)0.003 (3)−0.032 (4)−0.003 (3)

Geometric parameters (Å, °)

S1—O81.422 (3)C7—H7A0.9700
S1—O91.427 (3)C7—H7B0.9700
S1—O71.576 (3)C8—C91.496 (7)
S1—C141.753 (5)C9—H9A0.9600
Cl1—C41.798 (5)C9—H9B0.9600
O1—C51.426 (5)C9—H9C0.9600
O1—C11.437 (5)C10—C111.490 (8)
O2—C81.189 (7)C11—H11A0.9600
O3—C101.337 (6)C11—H11B0.9600
O3—C21.449 (5)C11—H11C0.9600
O4—C101.20 (4)C12—C131.488 (8)
O4'—C101.222 (16)C13—H13A0.9600
O5—C121.370 (6)C13—H13B0.9600
O5—C31.447 (5)C13—H13C0.9600
O6—C121.184 (6)C14—C191.388 (6)
O7—C61.459 (6)C14—C151.393 (6)
O10—C211.24 (5)C15—C161.375 (7)
O10—H100.8200C15—H15A0.9300
C1—C71.515 (6)C16—C171.367 (7)
C1—C21.530 (6)C16—H16A0.9300
C1—H1A0.9800C17—C181.392 (7)
C2—C31.527 (6)C17—C201.503 (8)
C2—H2A0.9800C18—C191.371 (8)
C3—C41.514 (7)C18—H18A0.9300
C3—H3A0.9800C19—H19A0.9300
C4—C51.521 (6)C20—H20A0.9600
C4—H4A0.9800C20—H20B0.9600
C5—C61.503 (6)C20—H20D0.9600
C5—H5A0.9800C21—H21A0.9600
C6—H6A0.9700C21—H21B0.9600
C6—H6B0.9700C21—H21C0.9600
C7—C81.516 (7)
O8—S1—O9120.2 (2)C8—C9—H9B109.5
O8—S1—O7104.3 (2)H9A—C9—H9B109.5
O9—S1—O7108.28 (18)C8—C9—H9C109.5
O8—S1—C14109.2 (2)H9A—C9—H9C109.5
O9—S1—C14108.4 (2)H9B—C9—H9C109.5
O7—S1—C14105.4 (2)O4—C10—O4'37.7 (13)
C5—O1—C1112.4 (3)O4—C10—O3116.9 (17)
C10—O3—C2119.2 (4)O4'—C10—O3122.0 (8)
C12—O5—C3116.3 (4)O4—C10—C11121.9 (16)
C6—O7—S1118.8 (3)O4'—C10—C11125.9 (8)
C21—O10—H10109.5O3—C10—C11111.3 (6)
O1—C1—C7107.6 (4)C10—C11—H11A109.5
O1—C1—C2108.8 (3)C10—C11—H11B109.5
C7—C1—C2112.7 (4)H11A—C11—H11B109.5
O1—C1—H1A109.2C10—C11—H11C109.5
C7—C1—H1A109.2H11A—C11—H11C109.5
C2—C1—H1A109.2H11B—C11—H11C109.5
O3—C2—C3106.9 (3)O6—C12—O5122.5 (5)
O3—C2—C1107.6 (3)O6—C12—C13127.3 (5)
C3—C2—C1109.5 (3)O5—C12—C13110.1 (5)
O3—C2—H2A110.9C12—C13—H13A109.5
C3—C2—H2A110.9C12—C13—H13B109.5
C1—C2—H2A110.9H13A—C13—H13B109.5
O5—C3—C4111.4 (3)C12—C13—H13C109.5
O5—C3—C2108.8 (3)H13A—C13—H13C109.5
C4—C3—C2111.0 (4)H13B—C13—H13C109.5
O5—C3—H3A108.6C19—C14—C15120.5 (4)
C4—C3—H3A108.6C19—C14—S1118.9 (4)
C2—C3—H3A108.6C15—C14—S1120.5 (3)
C3—C4—C5109.5 (4)C16—C15—C14118.6 (5)
C3—C4—Cl1111.1 (3)C16—C15—H15A120.7
C5—C4—Cl1110.6 (3)C14—C15—H15A120.7
C3—C4—H4A108.5C17—C16—C15122.6 (5)
C5—C4—H4A108.5C17—C16—H16A118.7
Cl1—C4—H4A108.5C15—C16—H16A118.7
O1—C5—C6107.8 (4)C16—C17—C18117.5 (5)
O1—C5—C4110.5 (4)C16—C17—C20122.7 (6)
C6—C5—C4112.7 (4)C18—C17—C20119.8 (5)
O1—C5—H5A108.6C19—C18—C17122.3 (4)
C6—C5—H5A108.6C19—C18—H18A118.8
C4—C5—H5A108.6C17—C18—H18A118.8
O7—C6—C5106.9 (4)C18—C19—C14118.6 (5)
O7—C6—H6A110.4C18—C19—H19A120.7
C5—C6—H6A110.4C14—C19—H19A120.7
O7—C6—H6B110.4C17—C20—H20A109.5
C5—C6—H6B110.4C17—C20—H20B109.5
H6A—C6—H6B108.6H20A—C20—H20B109.5
C1—C7—C8115.2 (4)C17—C20—H20D109.5
C1—C7—H7A108.5H20A—C20—H20D109.5
C8—C7—H7A108.5H20B—C20—H20D109.5
C1—C7—H7B108.5O10—C21—H21A109.5
C8—C7—H7B108.5O10—C21—H21B109.5
H7A—C7—H7B107.5H21A—C21—H21B109.5
O2—C8—C9122.3 (5)O10—C21—H21C109.5
O2—C8—C7122.5 (5)H21A—C21—H21C109.5
C9—C8—C7115.2 (5)H21B—C21—H21C109.5
C8—C9—H9A109.5
O8—S1—O7—C6167.7 (4)O1—C5—C6—O774.9 (5)
O9—S1—O7—C638.6 (4)C4—C5—C6—O7−162.9 (4)
C14—S1—O7—C6−77.2 (4)O1—C1—C7—C8−81.7 (5)
C5—O1—C1—C7174.6 (4)C2—C1—C7—C8158.4 (4)
C5—O1—C1—C2−63.0 (5)C1—C7—C8—O21.7 (8)
C10—O3—C2—C3−121.1 (5)C1—C7—C8—C9−177.0 (5)
C10—O3—C2—C1121.3 (5)C2—O3—C10—O4−31 (2)
O1—C1—C2—O3173.3 (3)C2—O3—C10—O4'12 (2)
C7—C1—C2—O3−67.5 (5)C2—O3—C10—C11−177.5 (5)
O1—C1—C2—C357.5 (4)C3—O5—C12—O60.8 (7)
C7—C1—C2—C3176.7 (4)C3—O5—C12—C13179.5 (5)
C12—O5—C3—C496.5 (4)O8—S1—C14—C1925.0 (5)
C12—O5—C3—C2−140.9 (4)O9—S1—C14—C19157.6 (4)
O3—C2—C3—O566.7 (4)O7—S1—C14—C19−86.6 (4)
C1—C2—C3—O5−177.1 (3)O8—S1—C14—C15−151.0 (4)
O3—C2—C3—C4−170.5 (3)O9—S1—C14—C15−18.4 (4)
C1—C2—C3—C4−54.3 (5)O7—S1—C14—C1597.4 (4)
O5—C3—C4—C5174.4 (4)C19—C14—C15—C16−0.5 (7)
C2—C3—C4—C553.1 (5)S1—C14—C15—C16175.4 (4)
O5—C3—C4—Cl152.0 (5)C14—C15—C16—C170.0 (8)
C2—C3—C4—Cl1−69.4 (4)C15—C16—C17—C181.1 (8)
C1—O1—C5—C6−173.7 (4)C15—C16—C17—C20−177.5 (5)
C1—O1—C5—C462.8 (5)C16—C17—C18—C19−1.8 (8)
C3—C4—C5—O1−56.3 (5)C20—C17—C18—C19176.8 (5)
Cl1—C4—C5—O166.5 (4)C17—C18—C19—C141.3 (8)
C3—C4—C5—C6−176.9 (4)C15—C14—C19—C18−0.2 (7)
Cl1—C4—C5—C6−54.2 (5)S1—C14—C19—C18−176.2 (4)
S1—O7—C6—C5−174.1 (3)

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BH2169).

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