organic compounds
E)-4,6-dimethoxy-2-(4-methoxystyryl)-3-methylbenzaldehyde
of (aDivision of Bioscience and Biotechnology, BMIC, Konkuk University, Seoul 143-701, Republic of Korea, and bDepartment of Applied Chemistry, Dongduk Women's University, Seoul 136-714, Republic of Korea
*Correspondence e-mail: dskoh@dongduk.ac.kr
In the title molecule, C19H20O4, the central C=C double bond adopts an E configuration. The dihedral angle formed by the planes of the two benzene rings is 83.57 (12)°. The three methoxy groups are essentially coplanar with the benzene rings to which they are attached, with C C—O—C torsion angles of −0.2 (3), −2.3 (3) and −4.1 (3)°.
CCDC reference: 1425329
1. Related literature
For the synthesis and biological properties of resveratrol derivatives, see: Chen et al. (2015); Chillemi et al. (2015); Li et al. (2014); Shin et al. (2014); Huang et al. (2007). For related structures, see: Ge et al. (2013); Tang et al. (2011).
2. Experimental
2.1. Crystal data
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2.2. Data collection
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2.3. Refinement
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Data collection: SMART (Bruker, 2000); cell 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
CCDC reference: 1425329
10.1107/S2056989015017363/lh5786sup1.cif
contains datablocks I, New_Global_Publ_Block. DOI:Structure factors: contains datablock I. DOI: 10.1107/S2056989015017363/lh5786Isup2.hkl
Supporting information file. DOI: 10.1107/S2056989015017363/lh5786Isup3.cml
Resveratrol is part of a family of the stilbene polyphenols which has a general C6—C2—C6 carbon framework. Recent research has shown that resveratrol derivatives have diverse biological activities including anti-Alzheimer's disease (Li et al., 2014), anticancer (Chillemi et al., 2015), and anti-inflammatory (Chen et al., 2015). On our going research project of polyphenols (Shin et al., 2014), the title compound was synthesized and its
was determined.After the methylation of hydroxyl groups in resveratrol, formylation of the resulting compound was performed (Fig 2). The Vilslmeier formylation reaction gave two products depending on reaction conditions (Huang et al., 2007). The title compound (I) contains one formyl group and one methyl group at each ortho position of the dimethoxy-substituted benzene ring. Whereas compound (II) has only a formyl group at the ortho position of the benzene ring. The
of compound (II) has been published recently (Ge et al. 2013). In this report, the title compound (I) was synthesized and its was determined. According to the literature (Ge et al. 2013), compound (II) contains two independent molecules in the and the dihedral angle between the two benzene rings in each are 23.54 (12)°, and 31.11 (12)°. However, in (I), dihedral angle between the two benzene rings is 83.57 (12)° (Fig. 1). The methoxy groups are essentially co-planar with the attached the benzene rings [C4—C3—O1—C8 = -0.2 (3)°, C4—C5—O2—C9 = -2.3 (3)° and C17—C16—O4—C19 = -4.1 (3)°].For an outline of the synthesis see Fig. 2. Resveratrol (A, 30 mmol, 6.8 g) was dissolved in 75 mL of aq. NaOH (10%) under ice-water bath conditions. To the above solution, was added DMS (50 mL) and the reaction mixture was stirred at room temperature for 24 h. After completion of this reaction, the mixture was extracted with EtOAc (50 mL x 3) and the combined organic layer was dried under MgSO4. Filtration and evaporation of the solvent gave a solid of compound B. To a solution of compound B (10 mmol, 2.7 g) in 20 mL of DMF was added 2 mL of POCl3 in an ice-water bath, and was stirred at room temperature for 4 h. The reaction mixture was poured into ice-water and stirred for 2 h. The reaction mixture was extracted with EtOAc (30 mL x 3). Evaporation of the organic solvent afforded mixture of products (I) and (II), which was purified by
Recrystallization of solid (I) from ethanol gave single crystals which were suitable for X-ray diffraction (m.p.: 391–392 K).H atoms bonded to C atoms were placed in calculated positions, with C—H distances in the range 0.95–0.98 Å, and included in the
in a riding-model approximation, with Uiso(H) = 1.5Ueq(C) for methyl H atoms and 1.5Ueq(C) otherwise.Data collection: SMART (Bruker, 2000); cell
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).C19H20O4 | F(000) = 664 |
Mr = 312.35 | Dx = 1.318 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 3256 reflections |
a = 11.3632 (9) Å | θ = 2.7–28.2° |
b = 8.7159 (7) Å | µ = 0.09 mm−1 |
c = 16.2382 (13) Å | T = 200 K |
β = 101.927 (2)° | Block, light yellow |
V = 1573.5 (2) Å3 | 0.26 × 0.20 × 0.13 mm |
Z = 4 |
Bruker SMART CCD diffractometer | 1966 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.037 |
Graphite monochromator | θmax = 28.3°, θmin = 1.8° |
φ and ω scans | h = −15→14 |
11266 measured reflections | k = −11→11 |
3904 independent reflections | l = −16→21 |
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)] = 0.057 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.222 | H-atom parameters constrained |
S = 0.99 | w = 1/[σ2(Fo2) + (0.1179P)2] where P = (Fo2 + 2Fc2)/3 |
3904 reflections | (Δ/σ)max < 0.001 |
212 parameters | Δρmax = 0.24 e Å−3 |
0 restraints | Δρmin = −0.31 e Å−3 |
C19H20O4 | V = 1573.5 (2) Å3 |
Mr = 312.35 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 11.3632 (9) Å | µ = 0.09 mm−1 |
b = 8.7159 (7) Å | T = 200 K |
c = 16.2382 (13) Å | 0.26 × 0.20 × 0.13 mm |
β = 101.927 (2)° |
Bruker SMART CCD diffractometer | 1966 reflections with I > 2σ(I) |
11266 measured reflections | Rint = 0.037 |
3904 independent reflections |
R[F2 > 2σ(F2)] = 0.057 | 0 restraints |
wR(F2) = 0.222 | H-atom parameters constrained |
S = 0.99 | Δρmax = 0.24 e Å−3 |
3904 reflections | Δρmin = −0.31 e Å−3 |
212 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.8260 (2) | 0.0967 (3) | 0.05627 (14) | 0.0374 (5) | |
C2 | 0.7634 (2) | 0.0081 (3) | −0.01021 (15) | 0.0400 (6) | |
C3 | 0.7955 (2) | 0.0212 (3) | −0.08861 (14) | 0.0398 (6) | |
C4 | 0.8854 (2) | 0.1179 (3) | −0.10269 (15) | 0.0408 (6) | |
H4 | 0.9040 | 0.1253 | −0.1569 | 0.049* | |
C5 | 0.9481 (2) | 0.2042 (3) | −0.03599 (14) | 0.0384 (6) | |
C6 | 0.9196 (2) | 0.1962 (2) | 0.04419 (14) | 0.0368 (5) | |
C7 | 0.6658 (2) | −0.1046 (3) | −0.00234 (18) | 0.0568 (7) | |
H7A | 0.5871 | −0.0586 | −0.0248 | 0.085* | |
H7B | 0.6718 | −0.1308 | 0.0571 | 0.085* | |
H7C | 0.6752 | −0.1978 | −0.0342 | 0.085* | |
O1 | 0.73156 (16) | −0.0693 (2) | −0.15023 (11) | 0.0533 (5) | |
C8 | 0.7593 (3) | −0.0620 (3) | −0.23169 (15) | 0.0582 (8) | |
H8A | 0.7488 | 0.0435 | −0.2529 | 0.087* | |
H8B | 0.7054 | −0.1304 | −0.2700 | 0.087* | |
H8C | 0.8429 | −0.0940 | −0.2283 | 0.087* | |
O2 | 1.03780 (16) | 0.30232 (19) | −0.04472 (10) | 0.0481 (5) | |
C9 | 1.0693 (2) | 0.3103 (3) | −0.12493 (16) | 0.0516 (7) | |
H9A | 1.0958 | 0.2090 | −0.1400 | 0.077* | |
H9B | 1.1346 | 0.3846 | −0.1229 | 0.077* | |
H9C | 0.9991 | 0.3428 | −0.1672 | 0.077* | |
O3 | 0.97338 (18) | 0.3109 (2) | 0.18130 (11) | 0.0574 (5) | |
C10 | 0.9879 (2) | 0.2931 (3) | 0.10982 (16) | 0.0477 (6) | |
H10 | 1.0519 | 0.3497 | 0.0950 | 0.057* | |
C11 | 0.7965 (2) | 0.0880 (3) | 0.14099 (14) | 0.0404 (6) | |
H11 | 0.8607 | 0.0662 | 0.1871 | 0.049* | |
C12 | 0.6884 (2) | 0.1081 (3) | 0.15791 (15) | 0.0417 (6) | |
H12 | 0.6232 | 0.1226 | 0.1114 | 0.050* | |
C13 | 0.6605 (2) | 0.1098 (3) | 0.24196 (15) | 0.0414 (6) | |
C14 | 0.5693 (2) | 0.2034 (3) | 0.25915 (15) | 0.0464 (6) | |
H14 | 0.5208 | 0.2594 | 0.2145 | 0.056* | |
C15 | 0.5475 (2) | 0.2171 (3) | 0.33950 (16) | 0.0483 (6) | |
H15 | 0.4861 | 0.2839 | 0.3498 | 0.058* | |
C16 | 0.6156 (2) | 0.1327 (3) | 0.40527 (14) | 0.0405 (6) | |
C17 | 0.7041 (2) | 0.0355 (3) | 0.38910 (15) | 0.0441 (6) | |
H17 | 0.7495 | −0.0247 | 0.4332 | 0.053* | |
C18 | 0.7270 (2) | 0.0256 (3) | 0.30880 (14) | 0.0437 (6) | |
H18 | 0.7894 | −0.0400 | 0.2989 | 0.052* | |
O4 | 0.58605 (15) | 0.15293 (19) | 0.48210 (10) | 0.0480 (5) | |
C19 | 0.6468 (2) | 0.0587 (3) | 0.54938 (15) | 0.0524 (7) | |
H19A | 0.6389 | −0.0492 | 0.5322 | 0.079* | |
H19B | 0.6112 | 0.0739 | 0.5988 | 0.079* | |
H19C | 0.7322 | 0.0867 | 0.5633 | 0.079* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0382 (12) | 0.0403 (12) | 0.0348 (12) | 0.0087 (10) | 0.0102 (10) | 0.0032 (10) |
C2 | 0.0396 (13) | 0.0408 (13) | 0.0406 (13) | 0.0040 (10) | 0.0110 (10) | −0.0006 (10) |
C3 | 0.0390 (13) | 0.0406 (12) | 0.0399 (13) | 0.0023 (10) | 0.0080 (10) | −0.0043 (11) |
C4 | 0.0433 (13) | 0.0454 (13) | 0.0348 (12) | 0.0052 (11) | 0.0109 (10) | 0.0012 (10) |
C5 | 0.0375 (12) | 0.0407 (12) | 0.0389 (13) | 0.0049 (10) | 0.0124 (10) | 0.0022 (10) |
C6 | 0.0344 (12) | 0.0388 (12) | 0.0381 (12) | 0.0048 (10) | 0.0094 (10) | 0.0046 (10) |
C7 | 0.0569 (17) | 0.0580 (16) | 0.0592 (18) | −0.0107 (13) | 0.0205 (14) | −0.0078 (14) |
O1 | 0.0529 (11) | 0.0631 (11) | 0.0452 (10) | −0.0100 (9) | 0.0130 (8) | −0.0147 (9) |
C8 | 0.0631 (18) | 0.0748 (19) | 0.0369 (14) | −0.0077 (15) | 0.0108 (12) | −0.0130 (13) |
O2 | 0.0517 (10) | 0.0557 (11) | 0.0409 (10) | −0.0137 (8) | 0.0193 (8) | −0.0016 (8) |
C9 | 0.0583 (16) | 0.0561 (15) | 0.0462 (15) | −0.0048 (13) | 0.0246 (13) | 0.0014 (12) |
O3 | 0.0725 (13) | 0.0651 (12) | 0.0353 (10) | −0.0099 (9) | 0.0130 (9) | −0.0052 (9) |
C10 | 0.0480 (15) | 0.0541 (15) | 0.0405 (14) | −0.0051 (12) | 0.0077 (12) | −0.0004 (12) |
C11 | 0.0437 (13) | 0.0422 (12) | 0.0370 (13) | 0.0014 (10) | 0.0121 (10) | 0.0023 (10) |
C12 | 0.0430 (14) | 0.0477 (14) | 0.0360 (12) | −0.0019 (11) | 0.0116 (10) | 0.0014 (11) |
C13 | 0.0404 (13) | 0.0461 (13) | 0.0398 (13) | −0.0044 (10) | 0.0136 (10) | 0.0006 (11) |
C14 | 0.0417 (14) | 0.0613 (16) | 0.0375 (13) | 0.0047 (11) | 0.0109 (11) | 0.0046 (12) |
C15 | 0.0411 (14) | 0.0581 (15) | 0.0479 (15) | 0.0023 (12) | 0.0146 (11) | −0.0002 (12) |
C16 | 0.0406 (13) | 0.0494 (13) | 0.0339 (12) | −0.0095 (11) | 0.0129 (10) | −0.0052 (11) |
C17 | 0.0459 (14) | 0.0482 (14) | 0.0410 (13) | 0.0013 (11) | 0.0150 (11) | 0.0058 (11) |
C18 | 0.0432 (13) | 0.0451 (13) | 0.0454 (14) | 0.0024 (11) | 0.0150 (11) | 0.0022 (11) |
O4 | 0.0497 (10) | 0.0588 (11) | 0.0382 (9) | −0.0032 (8) | 0.0154 (8) | −0.0025 (8) |
C19 | 0.0594 (16) | 0.0543 (15) | 0.0431 (14) | −0.0127 (13) | 0.0100 (12) | 0.0003 (12) |
C1—C2 | 1.396 (3) | C9—H9C | 0.9800 |
C1—C6 | 1.417 (3) | O3—C10 | 1.215 (3) |
C1—C11 | 1.484 (3) | C10—H10 | 0.9500 |
C2—C3 | 1.399 (3) | C11—C12 | 1.325 (3) |
C2—C7 | 1.506 (3) | C11—H11 | 0.9500 |
C3—O1 | 1.360 (3) | C12—C13 | 1.463 (3) |
C3—C4 | 1.379 (3) | C12—H12 | 0.9500 |
C4—C5 | 1.388 (3) | C13—C14 | 1.391 (3) |
C4—H4 | 0.9500 | C13—C18 | 1.396 (3) |
C5—O2 | 1.360 (3) | C14—C15 | 1.383 (3) |
C5—C6 | 1.407 (3) | C14—H14 | 0.9500 |
C6—C10 | 1.453 (3) | C15—C16 | 1.393 (3) |
C7—H7A | 0.9800 | C15—H15 | 0.9500 |
C7—H7B | 0.9800 | C16—O4 | 1.369 (3) |
C7—H7C | 0.9800 | C16—C17 | 1.381 (3) |
O1—C8 | 1.423 (3) | C17—C18 | 1.384 (3) |
C8—H8A | 0.9800 | C17—H17 | 0.9500 |
C8—H8B | 0.9800 | C18—H18 | 0.9500 |
C8—H8C | 0.9800 | O4—C19 | 1.426 (3) |
O2—C9 | 1.422 (3) | C19—H19A | 0.9800 |
C9—H9A | 0.9800 | C19—H19B | 0.9800 |
C9—H9B | 0.9800 | C19—H19C | 0.9800 |
C2—C1—C6 | 120.5 (2) | H9A—C9—H9C | 109.5 |
C2—C1—C11 | 120.8 (2) | H9B—C9—H9C | 109.5 |
C6—C1—C11 | 118.6 (2) | O3—C10—C6 | 128.1 (2) |
C1—C2—C3 | 118.1 (2) | O3—C10—H10 | 115.9 |
C1—C2—C7 | 124.1 (2) | C6—C10—H10 | 115.9 |
C3—C2—C7 | 117.7 (2) | C12—C11—C1 | 125.6 (2) |
O1—C3—C4 | 122.2 (2) | C12—C11—H11 | 117.2 |
O1—C3—C2 | 115.0 (2) | C1—C11—H11 | 117.2 |
C4—C3—C2 | 122.8 (2) | C11—C12—C13 | 125.7 (2) |
C3—C4—C5 | 118.7 (2) | C11—C12—H12 | 117.1 |
C3—C4—H4 | 120.7 | C13—C12—H12 | 117.1 |
C5—C4—H4 | 120.7 | C14—C13—C18 | 117.3 (2) |
O2—C5—C4 | 122.3 (2) | C14—C13—C12 | 120.4 (2) |
O2—C5—C6 | 116.7 (2) | C18—C13—C12 | 122.2 (2) |
C4—C5—C6 | 121.1 (2) | C15—C14—C13 | 121.7 (2) |
C5—C6—C1 | 118.8 (2) | C15—C14—H14 | 119.1 |
C5—C6—C10 | 117.4 (2) | C13—C14—H14 | 119.1 |
C1—C6—C10 | 123.9 (2) | C14—C15—C16 | 119.9 (2) |
C2—C7—H7A | 109.5 | C14—C15—H15 | 120.1 |
C2—C7—H7B | 109.5 | C16—C15—H15 | 120.1 |
H7A—C7—H7B | 109.5 | O4—C16—C17 | 125.3 (2) |
C2—C7—H7C | 109.5 | O4—C16—C15 | 115.4 (2) |
H7A—C7—H7C | 109.5 | C17—C16—C15 | 119.3 (2) |
H7B—C7—H7C | 109.5 | C16—C17—C18 | 120.2 (2) |
C3—O1—C8 | 118.1 (2) | C16—C17—H17 | 119.9 |
O1—C8—H8A | 109.5 | C18—C17—H17 | 119.9 |
O1—C8—H8B | 109.5 | C17—C18—C13 | 121.5 (2) |
H8A—C8—H8B | 109.5 | C17—C18—H18 | 119.2 |
O1—C8—H8C | 109.5 | C13—C18—H18 | 119.2 |
H8A—C8—H8C | 109.5 | C16—O4—C19 | 116.92 (19) |
H8B—C8—H8C | 109.5 | O4—C19—H19A | 109.5 |
C5—O2—C9 | 117.52 (18) | O4—C19—H19B | 109.5 |
O2—C9—H9A | 109.5 | H19A—C19—H19B | 109.5 |
O2—C9—H9B | 109.5 | O4—C19—H19C | 109.5 |
H9A—C9—H9B | 109.5 | H19A—C19—H19C | 109.5 |
O2—C9—H9C | 109.5 | H19B—C19—H19C | 109.5 |
C6—C1—C2—C3 | −0.3 (3) | C4—C5—O2—C9 | −2.2 (3) |
C11—C1—C2—C3 | −179.9 (2) | C6—C5—O2—C9 | 179.0 (2) |
C6—C1—C2—C7 | 177.8 (2) | C5—C6—C10—O3 | 175.2 (2) |
C11—C1—C2—C7 | −1.9 (3) | C1—C6—C10—O3 | −4.0 (4) |
C1—C2—C3—O1 | 179.49 (19) | C2—C1—C11—C12 | −53.9 (3) |
C7—C2—C3—O1 | 1.3 (3) | C6—C1—C11—C12 | 126.4 (3) |
C1—C2—C3—C4 | −0.3 (3) | C1—C11—C12—C13 | −175.6 (2) |
C7—C2—C3—C4 | −178.5 (2) | C11—C12—C13—C14 | 146.5 (3) |
O1—C3—C4—C5 | −178.7 (2) | C11—C12—C13—C18 | −29.9 (4) |
C2—C3—C4—C5 | 1.0 (3) | C18—C13—C14—C15 | 2.1 (4) |
C3—C4—C5—O2 | −179.9 (2) | C12—C13—C14—C15 | −174.6 (2) |
C3—C4—C5—C6 | −1.2 (3) | C13—C14—C15—C16 | −1.7 (4) |
O2—C5—C6—C1 | 179.4 (2) | C14—C15—C16—O4 | −179.2 (2) |
C4—C5—C6—C1 | 0.7 (3) | C14—C15—C16—C17 | −0.3 (4) |
O2—C5—C6—C10 | 0.2 (3) | O4—C16—C17—C18 | −179.3 (2) |
C4—C5—C6—C10 | −178.6 (2) | C15—C16—C17—C18 | 1.8 (4) |
C2—C1—C6—C5 | 0.1 (3) | C16—C17—C18—C13 | −1.4 (4) |
C11—C1—C6—C5 | 179.75 (19) | C14—C13—C18—C17 | −0.5 (3) |
C2—C1—C6—C10 | 179.3 (2) | C12—C13—C18—C17 | 176.1 (2) |
C11—C1—C6—C10 | −1.0 (3) | C17—C16—O4—C19 | −4.1 (3) |
C4—C3—O1—C8 | −0.2 (3) | C15—C16—O4—C19 | 174.8 (2) |
C2—C3—O1—C8 | −180.0 (2) |
Experimental details
Crystal data | |
Chemical formula | C19H20O4 |
Mr | 312.35 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 200 |
a, b, c (Å) | 11.3632 (9), 8.7159 (7), 16.2382 (13) |
β (°) | 101.927 (2) |
V (Å3) | 1573.5 (2) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.26 × 0.20 × 0.13 |
Data collection | |
Diffractometer | Bruker SMART CCD diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 11266, 3904, 1966 |
Rint | 0.037 |
(sin θ/λ)max (Å−1) | 0.667 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.057, 0.222, 0.99 |
No. of reflections | 3904 |
No. of parameters | 212 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.24, −0.31 |
Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
References
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