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Acta Crystallogr Sect E Struct Rep Online. 2009 August 1; 65(Pt 8): o2044.
Published online 2009 July 31. doi:  10.1107/S1600536809029687
PMCID: PMC2977370

(E)-4-(β-d-Allopyran­os­yloxy)cinnamyl 4-bromo­phenyl ketone ethanol solvate

Abstract

The title compound, C21H21BrO7·C2H6O, was synthesized by the Claisen–Schimidt reaction of helicid (systematic name: 4-formyl­phenyl-β-d-allopyran­oside) with 4-bromo­aceto­phenone in ethanol. The pyran ring adopts a chair conformation. In the crystal structure, mol­ecules are linked into a three-dimensional network by inter­molecular O—H(...)O hydrogen bonds.

Related literature

For helicid and its biological activity, see: Chen et al. (1981 [triangle]); Sha & Mao (1987 [triangle]). For the synthesis and structure of related compound, see: Fan et al. (2007 [triangle]); Fu et al. (2009 [triangle]); Lv et al. (2009 [triangle]); Yang et al. (2009 [triangle]); Ye et al. (2009 [triangle]).

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Object name is e-65-o2044-scheme1.jpg

Experimental

Crystal data

  • C21H21BrO7·C2H6O
  • M r = 511.36
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o2044-efi1.jpg
  • a = 10.977 (2) Å
  • b = 7.6518 (15) Å
  • c = 13.259 (3) Å
  • β = 92.08 (3)°
  • V = 1113.0 (4) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 1.89 mm−1
  • T = 113 K
  • 0.20 × 0.16 × 0.12 mm

Data collection

  • Rigaku Saturn CCD area-detector diffractometer
  • Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005 [triangle]) T min = 0.703, T max = 0.805
  • 9199 measured reflections
  • 5171 independent reflections
  • 3636 reflections with I > 2σ(I)
  • R int = 0.039

Refinement

  • R[F 2 > 2σ(F 2)] = 0.032
  • wR(F 2) = 0.056
  • S = 0.75
  • 5171 reflections
  • 296 parameters
  • 1 restraint
  • H-atom parameters constrained
  • Δρmax = 0.67 e Å−3
  • Δρmin = −0.39 e Å−3
  • Absolute structure: Flack (1983 [triangle]), 2358 Friedel pairs
  • Flack parameter: 0.027 (6)

Data collection: CrystalClear (Rigaku/MSC, 2005 [triangle]); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXTL.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809029687/rz2355sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809029687/rz2355Isup2.hkl

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

Acknowledgments

The authors thank Mr Zhi-Hua Mao of the Analytical & Testing Center of Sichuan University for the X-ray data collection.

supplementary crystallographic information

Comment

Helicid (systematic name: 4-formylphenyl-β-D-allopyranoside; Chen et al. 1981), is a pure natural compound extracted from the fruit of Helicia Nilagirica Beed, which has been successfully used in the treatment of insomnia in China. Some helicid derivatives have been reported to possess good biological activities (Sha & Mao, 1987). The synthesis and structure of some helicid derivatives heve been recently reported by our group (Fu et al. 2009; Lv et al. 2009; Yang et al. 2009; Ye et al. 2009). As a continuation of our studies in this area, we report herein the crystal structure of the title compound.

In the molecule of the title compound (Fig. 1), the average of C–C, C(sp3)–O and C(sp2)–O bond lengths in the pyranoside unit are 1.524 (4), 1.421 (4) and 1.241 (3) Å, respectively. The pyran ring adopts chair conformation with the hydroxy group at C4 in axial position and the other substituents at C2, C3 and C5 in equatorial positions. The O1–C2–C3–O3 and O2–C1–C2–O1 torsion angles are -176.5 (2) ° and -59.0 (3) °, respectively, while the O5–C5–C6–O1 and O7–C15–C16–C21 torsion angles are -173.9 (2) ° and -172.2 (3) °, respectively, possibly as a consequence of the presence of O—H···O hydrogen bonds. In the crystal packing, the molecules are linked by intermolecular O—H···O hydrogen bonds (Table 1) involving the hydroxy groups of the pyranoside unit and the ethanol molecule to form a three-dimensional network.

Experimental

The synthetic method of the title compound was reported elsewhere (Fan et al., 2007). To a solution of helicid (1.420 g, 5 mmol) in 30 ml of anhydrous ethanol, a 10% NaOH aqueous solution were added under ice bath, then 4-bromoacetophenone (1.104 g, 5.5 mmol) was added. The mixture was neutralized with diluted hydrochloric acid, concentrated to half of the original volume, and the resulting precipitate filtered. Colourless single crystals suitable for X-ray analysis were obtained by slow evaporation of an ethanol solution (yield 65%, m.p. 98–100 K).

Refinement

H atoms were positioned geometrically and refined using a riding model, with C—H = 0.95–0.99 Å, O—H = 0.84 Å, and with Uiso(H) = 1.2Ueq(C) or 1.5Ueq (C, O) for methyl and hydroxy H atoms.

Figures

Fig. 1.
The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level.

Crystal data

C21H21BrO7·C2H6OF(000) = 528
Mr = 511.36Dx = 1.526 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 3521 reflections
a = 10.977 (2) Åθ = 1.5–27.9°
b = 7.6518 (15) ŵ = 1.89 mm1
c = 13.259 (3) ÅT = 113 K
β = 92.08 (3)°Block, colourless
V = 1113.0 (4) Å30.20 × 0.16 × 0.12 mm
Z = 2

Data collection

Rigaku Saturn CCD area-detector diffractometer5171 independent reflections
Radiation source: rotating anode3636 reflections with I > 2σ(I)
confocalRint = 0.039
Detector resolution: 7.31 pixels mm-1θmax = 27.9°, θmin = 1.5°
ω and [var phi] scansh = −14→14
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005)k = −10→10
Tmin = 0.703, Tmax = 0.805l = −13→17
9199 measured reflections

Refinement

Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.032w = 1/[σ2(Fo2)] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.056(Δ/σ)max = 0.003
S = 0.75Δρmax = 0.67 e Å3
5171 reflectionsΔρmin = −0.39 e Å3
296 parametersExtinction correction: SHELXL97 (Sheldrick, 2008)
1 restraintExtinction coefficient: 0.0242 (11)
Primary atom site location: structure-invariant direct methodsAbsolute structure: Flack (1983), 2358 Friedel pairs
Secondary atom site location: difference Fourier mapFlack parameter: 0.027 (6)

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
Br10.70240 (2)0.31136 (4)0.80385 (2)0.02313 (10)
O10.15927 (15)0.3593 (2)−0.22799 (13)0.0125 (5)
O20.08102 (18)0.0860 (3)−0.35522 (15)0.0166 (5)
H20.05530.0678−0.41470.025*
O3−0.04022 (16)0.4996 (3)−0.44247 (14)0.0162 (5)
H3−0.07880.5823−0.41690.024*
O40.05197 (19)0.7491 (2)−0.30705 (18)0.0153 (5)
H40.06910.8554−0.31360.023*
O50.32128 (15)0.7681 (2)−0.28189 (15)0.0164 (5)
H50.27770.8430−0.25410.025*
O60.32452 (16)0.4805 (3)−0.14705 (14)0.0143 (5)
O70.23659 (17)0.2120 (3)0.45816 (14)0.0192 (5)
C1−0.0025 (3)0.1941 (4)−0.3055 (2)0.0168 (8)
H1A−0.02090.1412−0.23960.020*
H1B−0.07960.2006−0.34640.020*
C20.0466 (2)0.3767 (4)−0.2884 (2)0.0122 (7)
H2A−0.01340.4455−0.24960.015*
C30.0726 (3)0.4741 (4)−0.3866 (2)0.0108 (7)
H3A0.12790.4012−0.42760.013*
C40.1343 (3)0.6463 (4)−0.3622 (2)0.0142 (7)
H4A0.15320.7077−0.42640.017*
C50.2521 (2)0.6144 (4)−0.3006 (2)0.0127 (7)
H5A0.30330.5322−0.33960.015*
C60.2173 (2)0.5219 (4)−0.2039 (2)0.0126 (7)
H60.16270.5976−0.16390.015*
C70.3110 (3)0.4342 (4)−0.0469 (2)0.0135 (7)
C80.1998 (2)0.4166 (4)−0.0018 (2)0.0145 (7)
H80.12580.4363−0.03940.017*
C90.1983 (2)0.3697 (4)0.0992 (2)0.0156 (7)
H90.12210.35840.13030.019*
C100.3045 (2)0.3390 (4)0.1562 (2)0.0136 (7)
C110.4158 (2)0.3544 (4)0.1087 (2)0.0190 (8)
H110.48990.33160.14570.023*
C120.4188 (2)0.4030 (4)0.0076 (2)0.0178 (7)
H120.49470.4147−0.02400.021*
C130.2936 (2)0.2962 (5)0.26334 (19)0.0167 (7)
H130.21270.28240.28510.020*
C140.3805 (2)0.2741 (4)0.3339 (2)0.0141 (7)
H140.46400.27960.31770.017*
C150.3446 (3)0.2406 (4)0.4391 (2)0.0142 (7)
C160.4376 (2)0.2468 (4)0.5234 (2)0.0116 (7)
C170.4006 (3)0.2023 (4)0.6211 (2)0.0146 (7)
H170.31990.16180.63020.017*
C180.4800 (2)0.2172 (4)0.7029 (2)0.0152 (7)
H180.45470.18720.76840.018*
C190.5973 (2)0.2762 (4)0.6893 (2)0.0150 (8)
C200.6379 (2)0.3148 (5)0.59468 (18)0.0139 (6)
H200.71940.35250.58640.017*
C210.5579 (2)0.2977 (5)0.51141 (18)0.0137 (6)
H210.58570.32110.44570.016*
O80.7446 (2)0.5264 (3)0.15901 (15)0.0236 (5)
H8A0.77020.62930.16610.035*
C220.7527 (2)0.4749 (4)0.0559 (2)0.0186 (7)
H22A0.71390.56520.01200.022*
H22B0.70760.36420.04480.022*
C230.8844 (2)0.4500 (4)0.0265 (2)0.0283 (9)
H23A0.92810.56120.03340.042*
H23B0.88620.4100−0.04370.042*
H23C0.92370.36260.07080.042*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Br10.02318 (17)0.03083 (19)0.01506 (14)−0.0005 (2)−0.00380 (11)−0.0020 (2)
O10.0135 (10)0.0100 (12)0.0137 (10)−0.0031 (9)−0.0042 (8)0.0028 (8)
O20.0266 (13)0.0125 (13)0.0105 (12)0.0026 (11)−0.0005 (10)−0.0007 (10)
O30.0193 (12)0.0162 (12)0.0128 (12)0.0055 (10)−0.0041 (9)−0.0025 (10)
O40.0169 (11)0.0075 (11)0.0216 (12)0.0025 (9)0.0040 (9)−0.0012 (9)
O50.0157 (11)0.0123 (14)0.0214 (12)−0.0043 (9)0.0046 (9)−0.0034 (9)
O60.0117 (11)0.0202 (13)0.0108 (11)−0.0012 (9)−0.0022 (9)0.0021 (10)
O70.0108 (11)0.0321 (14)0.0148 (12)−0.0053 (10)0.0011 (9)−0.0017 (10)
C10.020 (2)0.0157 (18)0.0144 (17)0.0003 (15)0.0014 (15)0.0018 (15)
C20.0133 (17)0.0116 (16)0.0118 (16)−0.0002 (13)−0.0007 (13)0.0000 (13)
C30.0106 (16)0.0127 (17)0.0091 (17)0.0015 (14)−0.0009 (13)0.0010 (14)
C40.0166 (18)0.0129 (17)0.0135 (17)0.0049 (14)0.0071 (14)0.0010 (14)
C50.0142 (16)0.0104 (17)0.0135 (16)−0.0022 (13)0.0021 (13)−0.0012 (13)
C60.0142 (17)0.0122 (16)0.0113 (16)0.0019 (14)−0.0012 (13)−0.0049 (14)
C70.0124 (16)0.0186 (18)0.0096 (16)−0.0005 (14)0.0014 (13)−0.0024 (14)
C80.0102 (16)0.0181 (18)0.0148 (17)0.0019 (14)−0.0060 (13)−0.0002 (14)
C90.0111 (15)0.0218 (18)0.0139 (16)0.0004 (13)0.0028 (12)−0.0018 (13)
C100.0123 (14)0.014 (2)0.0145 (14)−0.0020 (15)−0.0004 (11)−0.0002 (14)
C110.0130 (15)0.029 (2)0.0148 (15)−0.0016 (14)−0.0026 (12)0.0016 (14)
C120.0090 (16)0.0261 (19)0.0185 (17)−0.0015 (14)0.0011 (13)−0.0065 (14)
C130.0176 (15)0.0177 (17)0.0152 (14)−0.0017 (19)0.0037 (11)−0.0018 (18)
C140.0130 (15)0.014 (2)0.0159 (15)−0.0009 (14)0.0032 (12)0.0025 (14)
C150.0182 (17)0.0133 (16)0.0111 (16)0.0031 (13)−0.0010 (13)−0.0029 (13)
C160.0161 (16)0.0104 (15)0.0084 (15)0.0018 (13)0.0003 (12)−0.0021 (12)
C170.0119 (16)0.0166 (18)0.0155 (17)0.0010 (13)0.0045 (13)0.0006 (14)
C180.0198 (18)0.0188 (18)0.0072 (15)0.0014 (14)0.0009 (13)0.0029 (13)
C190.0176 (15)0.013 (2)0.0136 (14)0.0049 (14)−0.0041 (12)−0.0014 (14)
C200.0106 (13)0.0156 (14)0.0156 (13)−0.004 (2)−0.0002 (10)0.002 (2)
C210.0144 (14)0.0167 (16)0.0103 (13)−0.0015 (19)0.0045 (10)0.0022 (18)
O80.0384 (14)0.0154 (13)0.0172 (13)−0.0044 (11)0.0052 (11)−0.0017 (11)
C220.0192 (18)0.0199 (19)0.0164 (18)0.0015 (15)−0.0031 (14)−0.0034 (15)
C230.0161 (18)0.037 (2)0.031 (2)0.0019 (16)−0.0027 (15)−0.0014 (18)

Geometric parameters (Å, °)

Br1—C191.893 (3)C9—C101.385 (3)
O1—C61.429 (3)C9—H90.9500
O1—C21.456 (3)C10—C111.400 (3)
O2—C11.415 (3)C10—C131.468 (3)
O2—H20.8400C11—C121.394 (4)
O3—C31.433 (3)C11—H110.9500
O3—H30.8400C12—H120.9500
O4—C41.421 (3)C13—C141.323 (3)
O4—H40.8400C13—H130.9500
O5—C51.417 (3)C14—C151.485 (4)
O5—H50.8400C14—H140.9500
O6—C71.387 (3)C15—C161.487 (3)
O6—C61.411 (3)C16—C211.391 (3)
O7—C151.241 (3)C16—C171.413 (4)
C1—C21.511 (4)C17—C181.371 (4)
C1—H1A0.9900C17—H170.9500
C1—H1B0.9900C18—C191.382 (3)
C2—C31.535 (4)C18—H180.9500
C2—H2A1.0000C19—C201.378 (3)
C3—C41.511 (4)C20—C211.392 (3)
C3—H3A1.0000C20—H200.9500
C4—C51.524 (4)C21—H210.9500
C4—H4A1.0000O8—C221.429 (3)
C5—C61.526 (3)O8—H8A0.8400
C5—H5A1.0000C22—C231.523 (4)
C6—H61.0000C22—H22A0.9900
C7—C121.384 (4)C22—H22B0.9900
C7—C81.385 (4)C23—H23A0.9800
C8—C91.387 (4)C23—H23B0.9800
C8—H80.9500C23—H23C0.9800
C6—O1—C2114.0 (2)C8—C9—H9119.0
C1—O2—H2109.5C9—C10—C11118.2 (3)
C3—O3—H3109.5C9—C10—C13118.0 (2)
C4—O4—H4109.5C11—C10—C13123.8 (2)
C5—O5—H5109.5C12—C11—C10120.4 (3)
C7—O6—C6116.9 (2)C12—C11—H11119.8
O2—C1—C2112.1 (2)C10—C11—H11119.8
O2—C1—H1A109.2C7—C12—C11120.0 (3)
C2—C1—H1A109.2C7—C12—H12120.0
O2—C1—H1B109.2C11—C12—H12120.0
C2—C1—H1B109.2C14—C13—C10129.2 (2)
H1A—C1—H1B107.9C14—C13—H13115.4
O1—C2—C1106.8 (2)C10—C13—H13115.4
O1—C2—C3109.3 (2)C13—C14—C15118.5 (2)
C1—C2—C3113.5 (3)C13—C14—H14120.8
O1—C2—H2A109.0C15—C14—H14120.8
C1—C2—H2A109.0O7—C15—C14120.6 (2)
C3—C2—H2A109.0O7—C15—C16119.2 (3)
O3—C3—C4111.4 (2)C14—C15—C16120.2 (2)
O3—C3—C2108.7 (2)C21—C16—C17118.6 (2)
C4—C3—C2109.8 (2)C21—C16—C15123.4 (2)
O3—C3—H3A109.0C17—C16—C15118.0 (2)
C4—C3—H3A109.0C18—C17—C16120.6 (3)
C2—C3—H3A109.0C18—C17—H17119.7
O4—C4—C3107.7 (2)C16—C17—H17119.7
O4—C4—C5110.8 (2)C17—C18—C19119.5 (3)
C3—C4—C5109.9 (2)C17—C18—H18120.2
O4—C4—H4A109.5C19—C18—H18120.2
C3—C4—H4A109.5C20—C19—C18121.5 (2)
C5—C4—H4A109.5C20—C19—Br1119.5 (2)
O5—C5—C4113.6 (2)C18—C19—Br1119.0 (2)
O5—C5—C6112.8 (2)C19—C20—C21119.1 (2)
C4—C5—C6106.9 (2)C19—C20—H20120.4
O5—C5—H5A107.8C21—C20—H20120.4
C4—C5—H5A107.8C16—C21—C20120.6 (2)
C6—C5—H5A107.8C16—C21—H21119.7
O6—C6—O1106.3 (2)C20—C21—H21119.7
O6—C6—C5108.9 (2)C22—O8—H8A109.5
O1—C6—C5109.8 (2)O8—C22—C23111.9 (2)
O6—C6—H6110.6O8—C22—H22A109.2
O1—C6—H6110.6C23—C22—H22A109.2
C5—C6—H6110.6O8—C22—H22B109.2
C12—C7—C8120.5 (3)C23—C22—H22B109.2
C12—C7—O6115.1 (2)H22A—C22—H22B107.9
C8—C7—O6124.4 (3)C22—C23—H23A109.5
C7—C8—C9118.9 (3)C22—C23—H23B109.5
C7—C8—H8120.5H23A—C23—H23B109.5
C9—C8—H8120.5C22—C23—H23C109.5
C10—C9—C8122.1 (3)H23A—C23—H23C109.5
C10—C9—H9119.0H23B—C23—H23C109.5
C6—O1—C2—C1−179.3 (2)C7—C8—C9—C10−0.4 (5)
C6—O1—C2—C357.5 (3)C8—C9—C10—C11−0.7 (5)
O2—C1—C2—O1−59.0 (3)C8—C9—C10—C13177.9 (3)
O2—C1—C2—C361.6 (3)C9—C10—C11—C121.3 (5)
O1—C2—C3—O3−176.5 (2)C13—C10—C11—C12−177.2 (3)
C1—C2—C3—O364.4 (3)C8—C7—C12—C11−0.3 (4)
O1—C2—C3—C4−54.5 (3)O6—C7—C12—C11−179.5 (3)
C1—C2—C3—C4−173.6 (2)C10—C11—C12—C7−0.8 (5)
O3—C3—C4—O457.7 (3)C9—C10—C13—C14−174.7 (4)
C2—C3—C4—O4−62.7 (3)C11—C10—C13—C143.8 (6)
O3—C3—C4—C5178.6 (2)C10—C13—C14—C15176.7 (3)
C2—C3—C4—C558.1 (3)C13—C14—C15—O79.0 (4)
O4—C4—C5—O5−66.2 (3)C13—C14—C15—C16−169.0 (3)
C3—C4—C5—O5174.9 (2)O7—C15—C16—C21−172.2 (3)
O4—C4—C5—C658.8 (3)C14—C15—C16—C215.7 (4)
C3—C4—C5—C6−60.1 (3)O7—C15—C16—C176.2 (4)
C7—O6—C6—O1−76.7 (3)C14—C15—C16—C17−175.8 (3)
C7—O6—C6—C5165.1 (2)C21—C16—C17—C183.1 (4)
C2—O1—C6—O6−179.19 (19)C15—C16—C17—C18−175.5 (3)
C2—O1—C6—C5−61.5 (3)C16—C17—C18—C190.0 (4)
O5—C5—C6—O6−57.9 (3)C17—C18—C19—C20−2.3 (5)
C4—C5—C6—O6176.6 (2)C17—C18—C19—Br1175.7 (2)
O5—C5—C6—O1−173.9 (2)C18—C19—C20—C211.5 (5)
C4—C5—C6—O160.6 (3)Br1—C19—C20—C21−176.5 (3)
C6—O6—C7—C12−176.9 (3)C17—C16—C21—C20−3.9 (5)
C6—O6—C7—C83.9 (4)C15—C16—C21—C20174.6 (3)
C12—C7—C8—C90.9 (4)C19—C20—C21—C161.6 (6)
O6—C7—C8—C9−179.9 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O2—H2···O3i0.841.972.783 (3)164
O3—H3···O7ii0.842.052.702 (3)134
O3—H3···O40.842.382.786 (3)110
O4—H4···O2iii0.841.852.677 (3)166
O5—H5···O8iv0.841.912.678 (3)152
O8—H8A···O1iv0.842.082.893 (3)163

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: RZ2355).

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