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Acta Crystallogr Sect E Struct Rep Online. 2009 June 1; 65(Pt 6): o1338.
Published online 2009 May 20. doi:  10.1107/S1600536809018248
PMCID: PMC2969774

4-Formyl­phenyl 2,3,4,6-tetra-O-acetyl-β-d-allopyran­oside

Abstract

The title compound, C21H24O11, crystallizes exclusively as the β-anomer. The substituent of the protected sugar at position C-3 is in the axial position, while all other groups are in equatorial positions. The pyran­oside ring adopts a stable chair conformation.

Related literature

For the synthesis see: Chen et al. (1981 [triangle]); Wen et al. (2008 [triangle]). For the pharmacological activities of helicid derivatives, see: Fan et al. (2008 [triangle]), Sha et al. (1987 [triangle]). For related structures, see: Burkhardt et al. (2007a [triangle], 2007b [triangle])

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Object name is e-65-o1338-scheme1.jpg

Experimental

Crystal data

  • C21H24O11
  • M r = 452.40
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1338-efi1.jpg
  • a = 7.056 (4) Å
  • b = 17.758 (6) Å
  • c = 9.129 (3) Å
  • β = 102.80 (4)°
  • V = 1115.4 (8) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.11 mm−1
  • T = 291 K
  • 0.44 × 0.42 × 0.20 mm

Data collection

  • Enraf–Nonius CAD-4 diffractometer
  • Absorption correction: none
  • 4596 measured reflections
  • 4149 independent reflections
  • 2143 reflections with I > 2σ(I)
  • R int = 0.029
  • 3 standard reflections every 150 reflections intensity decay: 3.7%

Refinement

  • R[F 2 > 2σ(F 2)] = 0.050
  • wR(F 2) = 0.143
  • S = 0.95
  • 4149 reflections
  • 293 parameters
  • 1 restraint
  • H-atom parameters constrained
  • Δρmax = 0.30 e Å−3
  • Δρmin = −0.20 e Å−3

Data collection: DIFRAC (Gabe & White, 1993 [triangle]); cell refinement: DIFRAC; data reduction: NRCVAX (Gabe et al., 1989 [triangle]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]); software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809018248/bx2200sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809018248/bx2200Isup2.hkl

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

Acknowledgments

The authors thank Mr Zhi-Hua Mao of Sichuan University for the data collection.

supplementary crystallographic information

Comment

The natural compound helicid, 4-(β-D-allopyranosyloxy)benzaldehyde (Chen et al., 1981), is a major active ingredient of Chinese herbal medicine, which has good biological effects on central nervous system with low toxicity (Sha et al., 1987). Some helicid derivatives have been reported with good pharmacological activities (Fan et al., 2008). The title compound, a new helicid derivative, was synthesized via reaction of helicid and acetyl anhydride with good yield of 98% (Wen et al., 2008). Herein, we describe the structure of 4-formylphenyl-2,3, 4,6-tetra-O-acetyl-β-D-allopyranoside which compare well with the related structures 3-Formylphenyl-2,3,4,6-tetra-O-acetyl-β-D– glucopyranoside (Burkhardt et al., 2007a) and 3-Formylphenyl-2,3,4,6-tetra-O-acetyl-α -D– glucopyranoside (Burkhardt et al., 2007b) . The 4-formylphenyl group is subsituted at anomeric atom C1. The remaining hydroxy groups at C2, C3, C4 and C6 are protected by acetyl groups. Due to its hydrophobic substituents the compound is soluble in less polar solvents such as CH2Cl2. The 4-formylphenyl substituent at C1 is in an equatorial position, corresponding to the exclusive presence of the β anomer of the saccharide.The substituent of the protected sugar at C3 is in the axial position.

Experimental

To a solution of helicid (1.0 g, 3.5 mmol) in 2 ml of DMF and 3 ml of TEA was added dropwise acetyl anhydride (2.5 g, 25 mmol) under ice bath. The mixture was stirred vigorously at room temperature 5 h, and then poured into 20 ml of ice water. The precipitate was filtered, washed with water, and recrystallized with ethanol. By slow evaporation at room temperature, we got colorless crystals, yield 98%, m.p.:408–409 K. IR (KBr): 1752, 1693, 1601, 1506, 1224, 1157, 1127, 1085, 914, 876; 1H NMR (400 MHz, CDCl3, 298 K): 2.18, 2.08, 2.05, 2.05 (4 s, 12H, CH3); 4.26–4.24 (m, 2H, H6a, H6e); 4.32–4.27 (m, 1H, H5); 5.16 (dd, 1H, J43 = 2.8 Hz, J45 = 9.9 Hz, H4); 5.19 (dd, 1H, J23 = 3.0 Hz, J21 = 8.1 Hz, H2); 5.48 (d, 1H, J12 = 8.1 Hz, H1); 5.75 (t, 1H, J32 = 2.9 Hz, H3); 7.85 (d, 2H, J89 = J1211 = 8.6 Hz, ArH); 7.13 (d, 2H, J910 = J1110 = 8.6 Hz, ArH); 9.91 (s, 1H, H—C=O) p.p.m. 13C NMR (100 MHz, CDCl3, 298 K): 191.2, 170.8, 170.6, 170.5, 169.8, 161.7, 132.3, 117.2, 99.0, 71.8, 71.1, 68.8, 67.2, 61.8, 21.2, 21.1,21.0 p.p.m. ESI-MS: m/z (%) = 475 [M + Na]+ (100). Analysis calculated for C21H24O11.

Refinement

H atoms were positioned geometrically (C—H = 0.93–0.98 Å) and refined using a riding model, with Uiso(H) = 1.2Ueq (methylene C, aromatic C), Uiso(H) = 1.5Ueq (methyl C).

Figures

Fig. 1.
The molecular structure of (I), with displacement ellipsoids drawn at the 30% probability level.

Crystal data

C21H24O11F(000) = 476
Mr = 452.40Dx = 1.347 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 33 reflections
a = 7.056 (4) Åθ = 4.6–9.4°
b = 17.758 (6) ŵ = 0.11 mm1
c = 9.129 (3) ÅT = 291 K
β = 102.80 (4)°Block, colourless
V = 1115.4 (8) Å30.44 × 0.42 × 0.20 mm
Z = 2

Data collection

Enraf–Nonius CAD-4 diffractometerRint = 0.029
Radiation source: fine-focus sealed tubeθmax = 32.5°, θmin = 2.3°
graphiteh = −10→10
ω/2θ scansk = −25→26
4596 measured reflectionsl = −13→13
4149 independent reflections3 standard reflections every 150 reflections
2143 reflections with I > 2σ(I) intensity decay: 3.7%

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.050Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.143H-atom parameters constrained
S = 0.95w = 1/[σ2(Fo2) + (0.0778P)2] where P = (Fo2 + 2Fc2)/3
4149 reflections(Δ/σ)max < 0.001
293 parametersΔρmax = 0.30 e Å3
1 restraintΔρmin = −0.20 e Å3

Special details

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)

xyzUiso*/Ueq
O10.4950 (3)0.63276 (10)0.1617 (2)0.0399 (4)
O20.2064 (3)0.55171 (14)−0.0604 (2)0.0526 (5)
O30.3692 (5)0.62506 (18)−0.1903 (3)0.0857 (9)
O40.2271 (3)0.48018 (11)0.2871 (2)0.0436 (4)
O5−0.0540 (3)0.52455 (15)0.3289 (4)0.0733 (8)
O60.5256 (3)0.54679 (12)0.5011 (2)0.0446 (4)
O70.3283 (4)0.48347 (14)0.6212 (3)0.0657 (7)
O80.5465 (3)0.69998 (12)0.5428 (2)0.0468 (5)
O90.2909 (5)0.7687 (2)0.5597 (4)0.1025 (12)
O100.6171 (3)0.74339 (10)0.2628 (2)0.0415 (4)
O111.2834 (4)0.88786 (18)−0.0222 (3)0.0780 (8)
C10.5854 (4)0.66770 (14)0.2979 (3)0.0370 (5)
H10.70700.64240.34540.044*
C20.4428 (4)0.67009 (15)0.4018 (3)0.0385 (6)
H20.33430.70360.35890.046*
C30.3648 (4)0.59176 (16)0.4229 (3)0.0394 (6)
H30.26270.59440.48010.047*
C40.2873 (4)0.55657 (15)0.2697 (3)0.0388 (6)
H40.17570.58580.21560.047*
C50.4441 (4)0.55511 (15)0.1781 (3)0.0382 (6)
H50.55810.52830.23520.046*
C60.3858 (4)0.52131 (17)0.0245 (3)0.0482 (7)
H6A0.48760.5304−0.02930.058*
H6B0.37230.46730.03380.058*
C70.2171 (6)0.6017 (2)−0.1706 (4)0.0620 (9)
C80.0234 (7)0.6216 (3)−0.2607 (5)0.0897 (13)
H8A0.02740.6713−0.30140.135*
H8B−0.06940.6204−0.19810.135*
H8C−0.01410.5862−0.34120.135*
C90.0503 (4)0.47285 (19)0.3242 (4)0.0528 (8)
C100.0162 (6)0.3927 (2)0.3635 (5)0.0743 (11)
H10A0.08860.38210.46340.111*
H10B0.05780.35960.29370.111*
H10C−0.11980.38510.35860.111*
C110.4840 (5)0.49291 (18)0.5944 (3)0.0535 (8)
C120.6629 (7)0.4484 (3)0.6583 (6)0.0856 (13)
H12A0.71670.46480.75910.128*
H12B0.75660.45570.59780.128*
H12C0.63030.39590.65900.128*
C130.4540 (5)0.75101 (18)0.6110 (4)0.0563 (8)
C140.5769 (7)0.7780 (3)0.7549 (5)0.0842 (13)
H14A0.53450.82730.77710.126*
H14B0.71000.78040.74650.126*
H14C0.56560.74390.83410.126*
C150.7685 (4)0.75945 (14)0.1960 (3)0.0359 (5)
C160.8011 (4)0.83541 (16)0.1761 (3)0.0430 (6)
H160.72230.87140.20690.052*
C170.9503 (4)0.85760 (16)0.1108 (3)0.0453 (7)
H170.97040.90850.09610.054*
C181.0703 (4)0.80472 (17)0.0669 (3)0.0417 (6)
C191.0361 (4)0.72875 (17)0.0863 (3)0.0460 (7)
H191.11670.69300.05680.055*
C200.8838 (4)0.70516 (16)0.1487 (3)0.0443 (6)
H200.85940.65420.15870.053*
C211.2373 (5)0.8255 (2)0.0018 (4)0.0587 (8)
H211.31260.7864−0.02240.070*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0456 (10)0.0342 (9)0.0435 (10)−0.0048 (8)0.0178 (8)0.0015 (8)
O20.0535 (12)0.0559 (12)0.0508 (11)−0.0077 (10)0.0171 (10)−0.0018 (10)
O30.101 (2)0.085 (2)0.0768 (18)−0.0286 (18)0.0309 (15)0.0115 (15)
O40.0422 (10)0.0337 (10)0.0598 (11)−0.0029 (8)0.0218 (9)0.0005 (9)
O50.0492 (13)0.0593 (16)0.121 (2)0.0022 (12)0.0392 (14)0.0042 (15)
O60.0462 (11)0.0442 (10)0.0462 (10)0.0045 (9)0.0162 (8)0.0099 (8)
O70.0768 (17)0.0592 (15)0.0691 (15)−0.0078 (13)0.0330 (13)0.0151 (13)
O80.0454 (11)0.0481 (11)0.0502 (11)−0.0016 (9)0.0177 (9)−0.0086 (9)
O90.102 (2)0.109 (3)0.097 (2)0.049 (2)0.0209 (18)−0.0315 (19)
O100.0459 (10)0.0294 (9)0.0559 (11)0.0004 (8)0.0257 (9)0.0009 (8)
O110.0760 (18)0.0810 (19)0.0855 (19)−0.0344 (15)0.0361 (15)−0.0012 (15)
C10.0399 (13)0.0320 (12)0.0432 (13)−0.0019 (10)0.0176 (11)0.0001 (11)
C20.0402 (14)0.0360 (13)0.0427 (13)0.0008 (11)0.0167 (11)−0.0013 (11)
C30.0367 (13)0.0387 (13)0.0478 (14)0.0010 (11)0.0197 (11)0.0035 (12)
C40.0374 (13)0.0300 (12)0.0521 (15)−0.0012 (11)0.0166 (11)0.0027 (11)
C50.0399 (14)0.0329 (13)0.0465 (14)−0.0001 (11)0.0195 (11)0.0010 (11)
C60.0526 (17)0.0426 (15)0.0540 (17)−0.0005 (13)0.0216 (14)−0.0051 (13)
C70.086 (3)0.0523 (19)0.0521 (18)−0.0007 (18)0.0236 (18)−0.0051 (15)
C80.099 (3)0.102 (3)0.063 (2)0.017 (3)0.006 (2)0.004 (2)
C90.0444 (16)0.0487 (18)0.070 (2)−0.0114 (15)0.0227 (14)−0.0075 (16)
C100.078 (3)0.049 (2)0.105 (3)−0.0242 (19)0.039 (2)0.005 (2)
C110.068 (2)0.0462 (17)0.0481 (16)0.0011 (15)0.0168 (15)0.0058 (14)
C120.089 (3)0.079 (3)0.088 (3)0.020 (2)0.018 (2)0.032 (2)
C130.070 (2)0.0432 (17)0.0644 (19)0.0026 (16)0.0339 (17)−0.0080 (15)
C140.096 (3)0.090 (3)0.077 (2)−0.037 (3)0.041 (2)−0.036 (2)
C150.0365 (13)0.0345 (13)0.0379 (13)−0.0017 (10)0.0108 (10)0.0020 (10)
C160.0446 (15)0.0302 (13)0.0559 (17)−0.0023 (11)0.0148 (13)−0.0053 (12)
C170.0479 (16)0.0354 (14)0.0534 (16)−0.0104 (12)0.0132 (13)−0.0016 (12)
C180.0395 (13)0.0463 (16)0.0408 (13)−0.0058 (12)0.0125 (11)0.0022 (12)
C190.0489 (16)0.0406 (15)0.0530 (16)0.0063 (13)0.0210 (13)0.0013 (12)
C200.0501 (15)0.0312 (13)0.0568 (16)0.0019 (12)0.0230 (13)0.0011 (12)
C210.0525 (18)0.070 (2)0.0581 (18)−0.0109 (17)0.0212 (15)0.0046 (17)

Geometric parameters (Å, °)

O1—C11.409 (3)C7—C81.474 (6)
O1—C51.441 (3)C8—H8A0.9600
O2—C71.356 (4)C8—H8B0.9600
O2—C61.435 (4)C8—H8C0.9600
O3—C71.201 (5)C9—C101.500 (5)
O4—C91.369 (4)C10—H10A0.9600
O4—C41.441 (3)C10—H10B0.9600
O5—C91.184 (4)C10—H10C0.9600
O6—C111.356 (4)C11—C121.494 (5)
O6—C31.441 (4)C12—H12A0.9600
O7—C111.189 (4)C12—H12B0.9600
O8—C131.347 (4)C12—H12C0.9600
O8—C21.435 (3)C13—C141.484 (5)
O9—C131.185 (5)C14—H14A0.9600
O10—C151.372 (3)C14—H14B0.9600
O10—C11.411 (3)C14—H14C0.9600
O11—C211.188 (5)C15—C161.387 (4)
C1—C21.529 (3)C15—C201.391 (4)
C1—H10.9800C16—C171.377 (4)
C2—C31.524 (4)C16—H160.9300
C2—H20.9800C17—C181.382 (4)
C3—C41.519 (4)C17—H170.9300
C3—H30.9800C18—C191.389 (4)
C4—C51.528 (3)C18—C211.479 (4)
C4—H40.9800C19—C201.388 (4)
C5—C61.497 (4)C19—H190.9300
C5—H50.9800C20—H200.9300
C6—H6A0.9700C21—H210.9300
C6—H6B0.9700
C1—O1—C5113.85 (19)H8B—C8—H8C109.5
C7—O2—C6117.3 (3)O5—C9—O4122.9 (3)
C9—O4—C4115.1 (2)O5—C9—C10126.4 (3)
C11—O6—C3116.5 (2)O4—C9—C10110.7 (3)
C13—O8—C2117.4 (2)C9—C10—H10A109.5
C15—O10—C1118.5 (2)C9—C10—H10B109.5
O1—C1—O10106.5 (2)H10A—C10—H10B109.5
O1—C1—C2109.2 (2)C9—C10—H10C109.5
O10—C1—C2105.9 (2)H10A—C10—H10C109.5
O1—C1—H1111.7H10B—C10—H10C109.5
O10—C1—H1111.7O7—C11—O6124.5 (3)
C2—C1—H1111.7O7—C11—C12125.8 (3)
O8—C2—C3110.5 (2)O6—C11—C12109.7 (3)
O8—C2—C1107.0 (2)C11—C12—H12A109.5
C3—C2—C1111.0 (2)C11—C12—H12B109.5
O8—C2—H2109.4H12A—C12—H12B109.5
C3—C2—H2109.4C11—C12—H12C109.5
C1—C2—H2109.4H12A—C12—H12C109.5
O6—C3—C4108.2 (2)H12B—C12—H12C109.5
O6—C3—C2107.6 (2)O9—C13—O8121.5 (3)
C4—C3—C2109.0 (2)O9—C13—C14126.2 (3)
O6—C3—H3110.7O8—C13—C14112.2 (3)
C4—C3—H3110.7C13—C14—H14A109.5
C2—C3—H3110.7C13—C14—H14B109.5
O4—C4—C3109.9 (2)H14A—C14—H14B109.5
O4—C4—C5108.1 (2)C13—C14—H14C109.5
C3—C4—C5110.7 (2)H14A—C14—H14C109.5
O4—C4—H4109.3H14B—C14—H14C109.5
C3—C4—H4109.3O10—C15—C16115.4 (2)
C5—C4—H4109.3O10—C15—C20124.1 (2)
O1—C5—C6108.0 (2)C16—C15—C20120.5 (2)
O1—C5—C4105.6 (2)C17—C16—C15120.0 (3)
C6—C5—C4115.9 (2)C17—C16—H16120.0
O1—C5—H5109.0C15—C16—H16120.0
C6—C5—H5109.0C16—C17—C18120.5 (3)
C4—C5—H5109.0C16—C17—H17119.8
O2—C6—C5112.4 (2)C18—C17—H17119.8
O2—C6—H6A109.1C17—C18—C19119.2 (3)
C5—C6—H6A109.1C17—C18—C21122.7 (3)
O2—C6—H6B109.1C19—C18—C21118.0 (3)
C5—C6—H6B109.1C20—C19—C18121.2 (3)
H6A—C6—H6B107.8C20—C19—H19119.4
O3—C7—O2122.4 (4)C18—C19—H19119.4
O3—C7—C8125.6 (4)C19—C20—C15118.6 (3)
O2—C7—C8111.9 (4)C19—C20—H20120.7
C7—C8—H8A109.5C15—C20—H20120.7
C7—C8—H8B109.5O11—C21—C18125.6 (4)
H8A—C8—H8B109.5O11—C21—H21117.2
C7—C8—H8C109.5C18—C21—H21117.2
H8A—C8—H8C109.5
C5—O1—C1—O10−177.44 (19)C3—C4—C5—C6179.7 (2)
C5—O1—C1—C2−63.6 (3)C7—O2—C6—C5104.7 (3)
C15—O10—C1—O1−76.9 (3)O1—C5—C6—O2−68.4 (3)
C15—O10—C1—C2167.0 (2)C4—C5—C6—O249.8 (3)
C13—O8—C2—C3−101.7 (3)C6—O2—C7—O3−6.0 (5)
C13—O8—C2—C1137.3 (2)C6—O2—C7—C8173.2 (3)
O1—C1—C2—O8175.1 (2)C4—O4—C9—O56.4 (5)
O10—C1—C2—O8−70.7 (3)C4—O4—C9—C10−171.0 (3)
O1—C1—C2—C354.4 (3)C3—O6—C11—O7−4.2 (5)
O10—C1—C2—C3168.6 (2)C3—O6—C11—C12176.3 (3)
C11—O6—C3—C4−94.4 (3)C2—O8—C13—O92.7 (5)
C11—O6—C3—C2148.0 (2)C2—O8—C13—C14−179.5 (3)
O8—C2—C3—O6−53.2 (3)C1—O10—C15—C16−174.9 (2)
C1—C2—C3—O665.4 (3)C1—O10—C15—C205.6 (4)
O8—C2—C3—C4−170.2 (2)O10—C15—C16—C17179.6 (2)
C1—C2—C3—C4−51.7 (3)C20—C15—C16—C17−0.8 (4)
C9—O4—C4—C378.4 (3)C15—C16—C17—C18−1.1 (4)
C9—O4—C4—C5−160.6 (2)C16—C17—C18—C191.5 (4)
O6—C3—C4—O458.7 (2)C16—C17—C18—C21−177.5 (3)
C2—C3—C4—O4175.4 (2)C17—C18—C19—C200.0 (4)
O6—C3—C4—C5−60.7 (3)C21—C18—C19—C20179.1 (3)
C2—C3—C4—C556.0 (3)C18—C19—C20—C15−1.9 (4)
C1—O1—C5—C6−169.3 (2)O10—C15—C20—C19−178.2 (3)
C1—O1—C5—C466.1 (3)C16—C15—C20—C192.3 (4)
O4—C4—C5—O1178.8 (2)C17—C18—C21—O11−1.5 (5)
C3—C4—C5—O1−60.7 (3)C19—C18—C21—O11179.4 (3)
O4—C4—C5—C659.3 (3)

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BX2200).

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