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Metal–flavonolate compounds are of significant current inter­est as synthetic models for quercetinase enzymes and as bioactive compounds of importance to human health. Zinc–3-hy­droxy­flavonolate compounds, including those of quercetin, kampferol, and morin, generally exhibit bidentate coordination to a single ZnII center. The bi­pyridine-ligated zinc–flavonolate compound reported herein, namely bis­(μ-4-oxo-2-phenyl-4H-chromen-3-olato)-κ3O3:O3,O43O3,O4:O3-bis­[(2,2′-bi­pyridine-κ2N,N′)zinc(II)] bis­(perchlorate), {[Zn2(C15H9O3)2(C10H8N2)2](ClO4)2}n, (1), provides an unusual example of bridging 3-hy­droxy­flavonolate ligation in a dinuclear metal complex. The symmetry-related ZnII centers of (1) exhibit a distorted octa­hedral geometry, with weak coordination of a perchlorate anion trans to the bridging deprotonated O atom of the flavonolate ligand. Variable-concentration conductivity measurements provide evidence that, when (1) is dissolved in CH3CN, the complex dissociates into monomers. 1H NMR resonances for (1) dissolved in d6-DMSO were assigned via HMQC to the H atoms of the flavonolate and bi­pyridine ligands. In CH3CN, (1) undergoes qu­anti­tative visible-light-induced CO release with a quantum yield [0.004 (1)] similar to that exhibited by other mononuclear zinc–3-hy­droxy­flavonolate complexes. Mass spectroscopic identification of the [(bpy)2Zn(O-benzoyl­salicylate)]+ ion provides evidence of CO release from the flavonol and of ligand exchange at the ZnII center.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S2053229617011366/lg3207sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S2053229617011366/lg3207Isup2.hkl
Contains datablock I

CCDC reference: 1566131

Computing details top

Data collection: COLLECT (Hooft, 1998); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997) and SIR97 (Altomare et al., 1999); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR2004 (Burla et al., 2007); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009) and ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Bis(µ-4-oxo-2-phenyl-4H-chromen-3-olato)-κ3O3:O3,O4;κ3O3,O4:O3-bis[(2,2'-bipyridine-κ2N,N')zinc(II)] bis(perchlorate) top
Crystal data top
[Zn2(C15H9O3)2(C10H8N2)2](ClO4)2F(000) = 1136
Mr = 1116.45Dx = 1.622 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
a = 10.6003 (2) ÅCell parameters from 5179 reflections
b = 14.0573 (3) Åθ = 1.0–27.5°
c = 15.8141 (2) ŵ = 1.24 mm1
β = 104.0158 (10)°T = 150 K
V = 2286.33 (7) Å3Prism, yellow
Z = 20.28 × 0.25 × 0.20 mm
Data collection top
Nonius KappaCCD
diffractometer
4417 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.016
Phi and ω scanθmax = 27.5°, θmin = 2.5°
Absorption correction: multi-scan
(DENZO-SMN; Otwinowski & Minor, 1997)
h = 1313
Tmin = 0.722, Tmax = 0.789k = 1618
8971 measured reflectionsl = 2020
5225 independent reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.037H-atom parameters constrained
wR(F2) = 0.093 w = 1/[σ2(Fo2) + (0.038P)2 + 2.5961P]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max = 0.001
5225 reflectionsΔρmax = 1.06 e Å3
341 parametersΔρmin = 0.51 e Å3
28 restraints
Special details top

Experimental. The program Denzo-SMN (Otwinowski & Minor, 1997) uses a scaling algorithm (Fox & Holmes, 1966) which effectively corrects for absorption effects. High redundancy data were used in the scaling program hence the 'multi-scan' code word was used. No transmission coefficients are available from the program (only scale factors for each frame). The scale factors in the experimental table are calculated from the 'size' command in the SHELXL-97 input file.

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
Zn10.63071 (2)0.45723 (2)0.49175 (2)0.02410 (9)
O10.50997 (14)0.44202 (10)0.57399 (9)0.0211 (3)
O20.54863 (16)0.33113 (11)0.44544 (10)0.0281 (3)
O30.36814 (17)0.21939 (11)0.62159 (10)0.0299 (4)
N10.76003 (18)0.47018 (13)0.41398 (12)0.0234 (4)
N20.75846 (17)0.55667 (13)0.56275 (11)0.0216 (4)
C10.4701 (2)0.35118 (15)0.57078 (13)0.0215 (4)
C20.4885 (2)0.29575 (15)0.49750 (14)0.0238 (4)
C30.4322 (2)0.20209 (16)0.48603 (15)0.0274 (5)
C40.4304 (3)0.14514 (17)0.41248 (16)0.0339 (5)
H40.46860.16780.36790.041*
C50.3734 (3)0.05677 (19)0.40522 (18)0.0410 (6)
H50.37220.01850.35550.049*
C60.3169 (3)0.02282 (19)0.47094 (19)0.0421 (6)
H60.27940.03890.46590.050*
C70.3152 (3)0.07794 (19)0.54257 (17)0.0389 (6)
H70.27570.05530.58660.047*
C80.3727 (2)0.16787 (17)0.54928 (15)0.0296 (5)
C90.4154 (2)0.31063 (15)0.63192 (14)0.0240 (4)
C100.4020 (2)0.35302 (16)0.71466 (14)0.0262 (5)
C110.4834 (3)0.42693 (18)0.75412 (15)0.0323 (5)
H110.54300.45440.72490.039*
C120.4778 (3)0.46066 (19)0.83612 (16)0.0382 (6)
H120.53270.51140.86220.046*
C130.3928 (3)0.4203 (2)0.87918 (16)0.0409 (6)
H130.39190.44150.93610.049*
C140.3090 (3)0.3495 (2)0.84028 (17)0.0398 (6)
H140.24920.32320.86990.048*
C150.3115 (2)0.31615 (18)0.75770 (16)0.0310 (5)
H150.25190.26840.73060.037*
C160.7600 (2)0.41937 (18)0.34236 (16)0.0319 (5)
H160.69930.36890.32630.038*
C170.8460 (3)0.43842 (19)0.29110 (16)0.0356 (6)
H170.84460.40140.24070.043*
C180.9335 (2)0.51187 (19)0.31430 (16)0.0327 (5)
H180.99300.52630.27980.039*
C190.9338 (2)0.56433 (17)0.38805 (15)0.0275 (5)
H190.99360.61510.40510.033*
C200.8458 (2)0.54196 (15)0.43692 (13)0.0206 (4)
C210.8386 (2)0.59469 (16)0.51706 (13)0.0209 (4)
C220.9060 (2)0.67780 (18)0.54329 (15)0.0287 (5)
H220.96060.70450.50990.034*
C230.8929 (2)0.72163 (19)0.61922 (16)0.0353 (6)
H230.93730.77950.63780.042*
C240.8148 (2)0.68084 (19)0.66787 (15)0.0344 (6)
H240.80730.70870.72120.041*
C250.7484 (2)0.59883 (18)0.63707 (14)0.0286 (5)
H250.69340.57100.66960.034*
Cl1A0.8773 (6)0.2224 (3)0.6510 (4)0.0346 (2)0.176 (2)
O4A0.8000 (14)0.1459 (9)0.6684 (9)0.0532 (7)0.176 (2)
O5A0.8154 (13)0.3096 (9)0.6666 (13)0.0697 (9)0.176 (2)
O6A0.9914 (17)0.2401 (16)0.7179 (12)0.0824 (12)0.176 (2)
O7A0.9252 (19)0.204 (2)0.5791 (11)0.0714 (13)0.176 (2)
Cl10.82388 (10)0.24761 (7)0.62407 (6)0.0346 (2)0.824 (2)
O40.7164 (3)0.18804 (19)0.63012 (18)0.0532 (7)0.824 (2)
O50.7794 (3)0.3426 (2)0.6089 (3)0.0697 (9)0.824 (2)
O60.9246 (4)0.2448 (3)0.7016 (2)0.0824 (12)0.824 (2)
O70.8706 (3)0.2153 (4)0.5529 (2)0.0714 (13)0.824 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Zn10.02362 (14)0.01885 (14)0.03314 (15)0.00616 (10)0.01330 (10)0.00421 (10)
O10.0244 (7)0.0154 (7)0.0250 (7)0.0041 (6)0.0088 (6)0.0008 (6)
O20.0371 (9)0.0208 (8)0.0307 (8)0.0088 (7)0.0166 (7)0.0038 (6)
O30.0450 (10)0.0189 (8)0.0281 (8)0.0085 (7)0.0135 (7)0.0042 (6)
N10.0225 (9)0.0212 (9)0.0277 (9)0.0006 (7)0.0083 (7)0.0030 (7)
N20.0215 (9)0.0224 (9)0.0217 (8)0.0049 (7)0.0066 (7)0.0011 (7)
C10.0237 (10)0.0169 (10)0.0235 (10)0.0007 (8)0.0051 (8)0.0030 (8)
C20.0280 (11)0.0191 (11)0.0247 (10)0.0028 (9)0.0073 (9)0.0021 (8)
C30.0330 (12)0.0185 (11)0.0306 (11)0.0053 (9)0.0076 (9)0.0007 (9)
C40.0425 (14)0.0242 (12)0.0372 (13)0.0076 (11)0.0140 (11)0.0047 (10)
C50.0532 (17)0.0270 (14)0.0439 (15)0.0112 (12)0.0141 (13)0.0108 (11)
C60.0549 (17)0.0228 (13)0.0485 (15)0.0158 (12)0.0127 (13)0.0018 (11)
C70.0546 (16)0.0255 (13)0.0383 (13)0.0153 (12)0.0146 (12)0.0042 (11)
C80.0387 (13)0.0201 (11)0.0296 (12)0.0055 (10)0.0077 (10)0.0017 (9)
C90.0292 (11)0.0167 (10)0.0256 (10)0.0014 (9)0.0061 (9)0.0040 (8)
C100.0328 (12)0.0223 (11)0.0238 (10)0.0070 (9)0.0075 (9)0.0083 (9)
C110.0426 (14)0.0282 (12)0.0254 (11)0.0015 (11)0.0066 (10)0.0042 (9)
C120.0497 (16)0.0329 (14)0.0287 (12)0.0109 (12)0.0031 (11)0.0008 (10)
C130.0493 (16)0.0460 (16)0.0277 (12)0.0247 (14)0.0101 (11)0.0028 (11)
C140.0409 (14)0.0472 (16)0.0381 (13)0.0206 (13)0.0227 (12)0.0125 (12)
C150.0311 (12)0.0299 (13)0.0342 (12)0.0093 (10)0.0121 (10)0.0090 (10)
C160.0337 (12)0.0265 (12)0.0363 (12)0.0025 (10)0.0100 (10)0.0094 (10)
C170.0411 (14)0.0385 (15)0.0297 (12)0.0115 (11)0.0138 (11)0.0055 (10)
C180.0322 (12)0.0389 (14)0.0319 (12)0.0097 (11)0.0172 (10)0.0064 (10)
C190.0235 (11)0.0315 (13)0.0288 (11)0.0012 (9)0.0089 (9)0.0062 (9)
C200.0198 (10)0.0195 (10)0.0227 (10)0.0022 (8)0.0055 (8)0.0029 (8)
C210.0195 (10)0.0225 (11)0.0208 (9)0.0015 (8)0.0051 (8)0.0040 (8)
C220.0266 (11)0.0310 (13)0.0285 (11)0.0095 (10)0.0071 (9)0.0000 (10)
C230.0347 (13)0.0357 (14)0.0341 (13)0.0144 (11)0.0055 (10)0.0108 (11)
C240.0354 (13)0.0420 (15)0.0259 (11)0.0061 (11)0.0077 (10)0.0100 (10)
C250.0283 (11)0.0354 (13)0.0239 (10)0.0051 (10)0.0096 (9)0.0005 (9)
Cl1A0.0377 (5)0.0353 (5)0.0355 (5)0.0105 (4)0.0178 (4)0.0056 (3)
O4A0.0634 (18)0.0483 (16)0.0586 (16)0.0300 (13)0.0354 (14)0.0149 (12)
O5A0.0449 (16)0.0405 (16)0.117 (3)0.0064 (13)0.0076 (17)0.0004 (17)
O6A0.080 (3)0.089 (2)0.059 (2)0.026 (3)0.021 (2)0.0048 (18)
O7A0.078 (3)0.085 (2)0.070 (2)0.025 (3)0.054 (2)0.027 (2)
Cl10.0377 (5)0.0353 (5)0.0355 (5)0.0105 (4)0.0178 (4)0.0056 (3)
O40.0634 (18)0.0483 (16)0.0586 (16)0.0300 (13)0.0354 (14)0.0149 (12)
O50.0449 (16)0.0405 (16)0.117 (3)0.0064 (13)0.0076 (17)0.0004 (17)
O60.080 (3)0.089 (2)0.059 (2)0.026 (3)0.021 (2)0.0048 (18)
O70.078 (3)0.085 (2)0.070 (2)0.025 (3)0.054 (2)0.027 (2)
Geometric parameters (Å, º) top
Zn1—O12.0448 (14)C12—H120.9500
Zn1—O22.0315 (16)C12—C131.377 (4)
Zn1—O1i2.1353 (15)C13—H130.9500
Zn1—N12.0595 (18)C13—C141.376 (4)
Zn1—N22.0765 (18)C14—H140.9500
Zn1—Zn1i3.0891 (5)C14—C151.394 (4)
O1—Zn1i2.1352 (15)C15—H150.9500
O1—C11.342 (3)C16—H160.9500
O2—C21.259 (3)C16—C171.385 (3)
O3—C81.364 (3)C17—H170.9500
O3—C91.372 (3)C17—C181.377 (4)
N1—C161.339 (3)C18—H180.9500
N1—C201.348 (3)C18—C191.379 (3)
N2—C211.351 (3)C19—H190.9500
N2—C251.343 (3)C19—C201.384 (3)
C1—C21.448 (3)C20—C211.486 (3)
C1—C91.367 (3)C21—C221.380 (3)
C2—C31.439 (3)C22—H220.9500
C3—C41.408 (3)C22—C231.386 (3)
C3—C81.391 (3)C23—H230.9500
C4—H40.9500C23—C241.383 (3)
C4—C51.374 (3)C24—H240.9500
C5—H50.9500C24—C251.377 (3)
C5—C61.403 (4)C25—H250.9500
C6—H60.9500Cl1A—O4A1.419 (10)
C6—C71.376 (4)Cl1A—O5A1.440 (11)
C7—H70.9500Cl1A—O6A1.422 (11)
C7—C81.396 (3)Cl1A—O7A1.377 (13)
C9—C101.476 (3)Cl1—O41.436 (2)
C10—C111.398 (3)Cl1—O51.417 (3)
C10—C151.403 (3)Cl1—O61.418 (3)
C11—H110.9500Cl1—O71.410 (3)
C11—C121.395 (3)
O2—Zn1—O181.87 (6)C10—C11—H11119.8
O2—Zn1—N198.67 (7)C12—C11—C10120.5 (2)
O1—Zn1—N1177.08 (7)C12—C11—H11119.8
O2—Zn1—N2161.55 (7)C11—C12—H12120.0
O1—Zn1—N298.81 (6)C13—C12—C11120.0 (3)
N1—Zn1—N279.76 (7)C13—C12—H12120.0
O2—Zn1—O1i102.45 (6)C12—C13—H13119.8
O1—Zn1—O1i84.73 (6)C14—C13—C12120.4 (2)
N1—Zn1—O1i97.93 (6)C14—C13—H13119.8
N2—Zn1—O1i95.96 (6)C13—C14—H14119.8
O1—Zn1—Zn1i43.49 (4)C13—C14—C15120.4 (2)
O1i—Zn1—Zn1i41.23 (4)C15—C14—H14119.8
O1—Zn1—N298.81 (6)C10—C15—H15120.0
O2—Zn1—Zn1i93.18 (5)C14—C15—C10120.0 (3)
N1—Zn1—Zn1i139.15 (5)C14—C15—H15120.0
N2—Zn1—Zn1i99.97 (5)N1—C16—H16119.1
Zn1—O1—Zn1i95.27 (6)N1—C16—C17121.8 (2)
C1—O1—Zn1108.39 (12)C17—C16—H16119.1
C1—O1—Zn1i115.85 (13)C16—C17—H17120.5
C2—O2—Zn1110.45 (14)C18—C17—C16119.0 (2)
C8—O3—C9120.67 (17)C18—C17—H17120.5
C16—N1—Zn1126.44 (16)C17—C18—H18120.3
C16—N1—C20119.29 (19)C17—C18—C19119.3 (2)
C20—N1—Zn1114.12 (14)C19—C18—H18120.3
C21—N2—Zn1112.90 (14)C18—C19—H19120.4
C25—N2—Zn1126.19 (15)C18—C19—C20119.1 (2)
C25—N2—C21119.11 (19)C20—C19—H19120.4
O1—C1—C2116.09 (18)N1—C20—C19121.5 (2)
O1—C1—C9123.63 (19)N1—C20—C21115.60 (18)
C9—C1—C2120.3 (2)C19—C20—C21122.9 (2)
O2—C2—C1119.88 (19)N2—C21—C20115.31 (18)
O2—C2—C3122.6 (2)N2—C21—C22121.4 (2)
C3—C2—C1117.46 (19)C22—C21—C20123.26 (19)
C4—C3—C2123.1 (2)C21—C22—H22120.6
C8—C3—C2118.2 (2)C21—C22—C23118.9 (2)
C8—C3—C4118.6 (2)C23—C22—H22120.6
C3—C4—H4120.0C22—C23—H23120.1
C5—C4—C3120.1 (2)C24—C23—C22119.8 (2)
C5—C4—H4120.0C24—C23—H23120.1
C4—C5—H5119.9C23—C24—H24120.9
C4—C5—C6120.2 (2)C25—C24—C23118.3 (2)
C6—C5—H5119.9C25—C24—H24120.9
C5—C6—H6119.6N2—C25—C24122.5 (2)
C7—C6—C5120.7 (2)N2—C25—H25118.8
C7—C6—H6119.6C24—C25—H25118.8
C6—C7—H7120.7O4A—Cl1A—O5A107.6 (9)
C6—C7—C8118.7 (2)O4A—Cl1A—O6A114.5 (11)
C8—C7—H7120.7O6A—Cl1A—O5A93.7 (12)
O3—C8—C3122.2 (2)O7A—Cl1A—O4A111.2 (13)
O3—C8—C7116.2 (2)O7A—Cl1A—O5A125.4 (15)
C3—C8—C7121.6 (2)O7A—Cl1A—O6A103.3 (14)
O3—C9—C10111.86 (18)O5—Cl1—O4108.93 (18)
C1—C9—O3120.71 (19)O5—Cl1—O6108.8 (2)
C1—C9—C10127.4 (2)O6—Cl1—O4111.7 (2)
C11—C10—C9121.0 (2)O7—Cl1—O4107.7 (2)
C11—C10—C15118.6 (2)O7—Cl1—O5109.6 (3)
C15—C10—C9120.3 (2)O7—Cl1—O6110.2 (2)
Zn1i—O1—C1—C289.22 (19)C4—C5—C6—C71.4 (5)
Zn1—O1—C1—C216.4 (2)C5—C6—C7—C81.0 (4)
Zn1i—O1—C1—C991.0 (2)C6—C7—C8—O3180.0 (2)
Zn1—O1—C1—C9163.38 (18)C6—C7—C8—C30.6 (4)
Zn1—O2—C2—C18.7 (3)C8—O3—C9—C11.2 (3)
Zn1—O2—C2—C3173.41 (18)C8—O3—C9—C10179.5 (2)
Zn1—N1—C16—C17175.30 (18)C8—C3—C4—C51.5 (4)
Zn1—N1—C20—C19175.72 (16)C9—O3—C8—C34.3 (3)
Zn1—N1—C20—C214.0 (2)C9—O3—C8—C7176.3 (2)
Zn1—N2—C21—C2015.7 (2)C9—C1—C2—O2174.1 (2)
Zn1—N2—C21—C22163.08 (17)C9—C1—C2—C37.9 (3)
Zn1—N2—C25—C24162.27 (19)C9—C10—C11—C12174.2 (2)
O1—C1—C2—O25.6 (3)C9—C10—C15—C14173.0 (2)
O1—C1—C2—C3172.35 (19)C10—C11—C12—C130.8 (4)
O1—C1—C9—O3175.31 (19)C11—C10—C15—C143.6 (3)
O1—C1—C9—C106.6 (4)C11—C12—C13—C142.8 (4)
O2—C2—C3—C45.2 (4)C12—C13—C14—C151.6 (4)
O2—C2—C3—C8177.2 (2)C13—C14—C15—C101.6 (4)
O3—C9—C10—C11155.6 (2)C15—C10—C11—C122.4 (3)
O3—C9—C10—C1520.9 (3)C16—N1—C20—C190.0 (3)
N1—C16—C17—C180.3 (4)C16—N1—C20—C21179.8 (2)
N1—C20—C21—N28.0 (3)C16—C17—C18—C190.3 (4)
N1—C20—C21—C22170.8 (2)C17—C18—C19—C200.2 (4)
N2—C21—C22—C231.4 (3)C18—C19—C20—N10.0 (3)
C1—C2—C3—C4172.7 (2)C18—C19—C20—C21179.7 (2)
C1—C2—C3—C84.9 (3)C19—C20—C21—N2172.3 (2)
C1—C9—C10—C1122.6 (4)C19—C20—C21—C229.0 (3)
C1—C9—C10—C15160.9 (2)C20—N1—C16—C170.1 (3)
C2—C1—C9—O35.0 (3)C20—C21—C22—C23179.9 (2)
C2—C1—C9—C10173.1 (2)C21—N2—C25—C241.4 (3)
C2—C3—C4—C5179.1 (2)C21—C22—C23—C241.1 (4)
C2—C3—C8—O31.0 (4)C22—C23—C24—C252.3 (4)
C2—C3—C8—C7179.6 (2)C23—C24—C25—N21.1 (4)
C3—C4—C5—C60.1 (4)C25—N2—C21—C20178.60 (19)
C4—C3—C8—O3178.7 (2)C25—N2—C21—C222.6 (3)
C4—C3—C8—C71.9 (4)
Symmetry code: (i) x+1, y+1, z+1.
Parameters of selected offset-stacked interactions involving the aromatic rings of (1). top
CgIaCgJaCg···Cg distance (Å)Dihedral angle (°)CgI_Perp (Å)CgJJ_Perp (Å)Slippage (Å)
Cg4Cg63.4378 (12)12.40 (1)3.3692 (9)-3.3317 (9)0.848
Cg5Cg83.5856 (14)8.09 (12)3.3794 (10)3.5040 (11)0.760
Cg6Cg74.1065 (14)10.49 (12)3.3678 (9)-3.6709 (11)1.841
Cg5Cg63.8258 (13)8.84 (11)3.5192 (10)-3.3228 (9)1.896
Note: (a) Cg4 is the centroid of the O3/C8/C3–C1/C9 ring, Cg5 that of the N1/C16–C20 ring, Cg6 that of the N2/C21–C25 ring, Cg7 that of the C3–C8 ring, and Cg8 that of the C10–C15 ring.
 

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