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ISSN: 2056-9890

catena-Poly[[di­aqua­copper(II)]-μ-7-oxa­bi­cyclo­[2.2.1]heptane-2,3-di­carboxyl­ato]

aZhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua, Zhejiang 321004, People's Republic of China, and, College of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004, Zhejiang, People's Republic of China
*Correspondence e-mail: huruiding@zjnu.cn

(Received 18 December 2008; accepted 5 January 2009; online 10 January 2009)

In the crystal structure of the title compound, [Cu(C8H8O5)(H2O)2]n, the Cu(II) cation is in a Jahn–Teller distorted six-coordination by two O atoms from water molecules, by the bridging O atom from the bicyclo moiety, by two carboxylate O atoms from two different carboxylate groups and by one carboxylate O atom from a symmetry-related bridging ligand.The polymeric structure is made up from double-strands propagating parallel to the c axis that are held together via inter­molecular O—H⋯O hydrogen bonds.

Related literature

For related literature, see: Yin et al. (2003[Yin, F.-L., Shen, J., Zou, J.-J. & Li, R.-C. (2003). Acta Chim. Sin. 61, 556-561.]).

[Scheme 1]

Experimental

Crystal data
  • [Cu(C8H8O5)(H2O)2]

  • Mr = 283.72

  • Orthorhombic, I b a 2

  • a = 10.5512 (4) Å

  • b = 19.3389 (9) Å

  • c = 9.7435 (4) Å

  • V = 1988.15 (14) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 2.22 mm−1

  • T = 296 (2) K

  • 0.29 × 0.20 × 0.12 mm

Data collection
  • Bruker APEXII area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.60, Tmax = 0.78

  • 7372 measured reflections

  • 2078 independent reflections

  • 1897 reflections with I > 2σ(I)

  • Rint = 0.021

Refinement
  • R[F2 > 2σ(F2)] = 0.022

  • wR(F2) = 0.059

  • S = 1.02

  • 2078 reflections

  • 157 parameters

  • 9 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.32 e Å−3

  • Δρmin = −0.38 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 857 Friedel pairs

  • Flack parameter: 0.001 (16)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1W—H1WA⋯O1i 0.842 (17) 2.05 (2) 2.835 (3) 154 (4)
O1W—H1WB⋯O2ii 0.852 (17) 1.91 (2) 2.731 (2) 161 (3)
O2W—H2WA⋯O1iii 0.871 (17) 2.001 (18) 2.870 (2) 175 (3)
O2W—H2WB⋯O1Wi 0.795 (18) 2.21 (3) 2.920 (3) 148 (3)
O2W—H2WB⋯O4i 0.795 (18) 2.20 (3) 2.780 (3) 130 (3)
Symmetry codes: (i) [x, -y, z-{\script{1\over 2}}]; (ii) -x, -y, z; (iii) [-x, y, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2004[Bruker (2004). SAINT and APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2004[Bruker (2004). SAINT and APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

7-Oxabicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride (norcantharidin), a traditional Chinese drug, has great anti-cancer activity. It has been widely used as an anticancer drug to treat hepatoma, lung cancer, esophagus cancer and gastric cancer for a long time. Copper is an essential microelement in human body and it exists in the form of copper proteins in animal bodies. Copper coordination compounds have strong bioactivity and various structures, therefore people pay more attention to them and have synthesized some complexes that have pronounced anticancer activity, bactericidal activity, anti-proliferative effect in recent years (Yin et al., 2003). In order to prepare compounds with pronounced anti-cancer activity, we synthesized CuII complex of norcantharidin, whose anti-cancer activity test is being carried out.

In the title compound, each CuII ion is six-coordinated by two oxygen atoms from water, one bridge oxygen, two carboxylate oxygen atoms in two different carboxylate groups and one carboxylate oxygen atom in another asymmetric unit. O4, O5, O2W and O1W lie in the equatorial plane with the torsion angle -1.004 (62)°. Carboxylate oxygen atom O2 and O3 from another bridge ligand unit are in the axial positions. The bond angle of O2—Cu1—O3 is 171.256 (73)°, so it forms a distorted octahedral. Owing to the binding of the bridge oxygen atom with Cu, two six-membered rings (Cu1—O5—C4—C5—C8—O4 and Cu1—O2—C7—C6—C1—O5) are created. In addition, a seven-membered ring (Cu1—O4—C8—C5—C6—C7—O2) is formed because of the coordination of carboxylate oxygen atoms O2 and O4. What's more, intermolecular hydrogen bonds of the complex make the compound more stable.

Related literature top

For related literature, see: Yin et al. (2003).

Experimental top

A mixture of norcantharidin and CuCl2.2H2O was dissolved in 20 mL absolute ethyl alcohol and stirred for 4 h at room temperature and then refluxed for 2 h at 333 K. The blue solution was filtered and after 2 weeks block green single crystals were obtained.

Refinement top

The H atoms bonded to C atoms were positioned geometrically and refined using a riding model [aliphatic C—H = 0.97 (2) Å, Uiso(H) = 1.2Ueq(C)]. The H atoms bonded to O atoms were located in a difference Fourier maps and refined with O—H distance restraints of 0.85 (2) and Uiso(H) = 1.5Ueq(O).

Computing details top

Data collection: SMART (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); 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: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A view of the molecule of (I) showing the atom-labelling scheme with displacement ellipsoids drawn at the 30% probability.
catena-Poly[[diaquacopper(II)]-µ-7-oxabicyclo[2.2.1]heptane-2,3- dicarboxylato] top
Crystal data top
[Cu(C8H8O5)(H2O)2]F(000) = 1160
Mr = 283.72Dx = 1.896 Mg m3
Orthorhombic, Iba2Mo Kα radiation, λ = 0.71073 Å
Hall symbol: I 2 -2cCell parameters from 4186 reflections
a = 10.5512 (4) Åθ = 2.1–27.5°
b = 19.3389 (9) ŵ = 2.22 mm1
c = 9.7435 (4) ÅT = 296 K
V = 1988.15 (14) Å3Block, green
Z = 80.29 × 0.20 × 0.12 mm
Data collection top
Bruker APEXII area-detector
diffractometer
2078 independent reflections
Radiation source: fine-focus sealed tube1897 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.021
ω scansθmax = 27.5°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1313
Tmin = 0.60, Tmax = 0.78k = 2125
7372 measured reflectionsl = 1012
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.022H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.059 w = 1/[σ2(Fo2) + (0.0368P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max < 0.001
2078 reflectionsΔρmax = 0.32 e Å3
157 parametersΔρmin = 0.38 e Å3
9 restraintsAbsolute structure: Flack (1983), 857 Freidel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.001 (16)
Crystal data top
[Cu(C8H8O5)(H2O)2]V = 1988.15 (14) Å3
Mr = 283.72Z = 8
Orthorhombic, Iba2Mo Kα radiation
a = 10.5512 (4) ŵ = 2.22 mm1
b = 19.3389 (9) ÅT = 296 K
c = 9.7435 (4) Å0.29 × 0.20 × 0.12 mm
Data collection top
Bruker APEXII area-detector
diffractometer
2078 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1897 reflections with I > 2σ(I)
Tmin = 0.60, Tmax = 0.78Rint = 0.021
7372 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.022H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.059Δρmax = 0.32 e Å3
S = 1.02Δρmin = 0.38 e Å3
2078 reflectionsAbsolute structure: Flack (1983), 857 Freidel pairs
157 parametersAbsolute structure parameter: 0.001 (16)
9 restraints
Special details top

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) top
xyzUiso*/Ueq
Cu10.243032 (19)0.040771 (14)0.45597 (9)0.02570 (9)
O10.08219 (15)0.14342 (9)0.76589 (19)0.0351 (4)
O1W0.11498 (18)0.05770 (11)0.4992 (2)0.0476 (6)
H1WA0.117 (3)0.0923 (14)0.447 (3)0.071*
H1WB0.044 (2)0.0648 (17)0.538 (3)0.071*
O20.12635 (15)0.09609 (10)0.5661 (2)0.0367 (5)
O2W0.16510 (19)0.08276 (13)0.2897 (2)0.0471 (6)
H2WA0.092 (2)0.1034 (16)0.283 (4)0.071*
H2WB0.170 (3)0.0631 (18)0.218 (3)0.071*
O30.34512 (15)0.02601 (8)0.85851 (18)0.0285 (4)
O40.31828 (14)0.00547 (9)0.63735 (17)0.0287 (4)
O50.38661 (12)0.13101 (8)0.4694 (2)0.0278 (3)
C10.3288 (2)0.19244 (12)0.5275 (3)0.0324 (6)
H1A0.25970.21120.47170.039*
C20.4418 (3)0.24140 (14)0.5415 (3)0.0458 (7)
H2A0.42840.27490.61420.055*
H2B0.45880.26550.45620.055*
C30.5491 (2)0.19062 (15)0.5777 (3)0.0421 (7)
H3A0.61590.19150.50920.051*
H3B0.58510.20070.66710.051*
C40.4799 (2)0.12166 (13)0.5777 (3)0.0284 (5)
H4A0.53570.08180.56350.034*
C50.39748 (19)0.11620 (12)0.7068 (2)0.0242 (5)
H5A0.44440.13360.78650.029*
C60.2864 (2)0.16753 (12)0.6698 (3)0.0269 (5)
H6A0.28630.20650.73430.032*
C70.1552 (2)0.13317 (12)0.6683 (3)0.0268 (5)
C80.35037 (18)0.04365 (11)0.7353 (3)0.0221 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu10.02380 (12)0.03211 (16)0.02120 (16)0.00285 (9)0.00032 (15)0.00532 (16)
O10.0333 (8)0.0431 (10)0.0290 (10)0.0053 (8)0.0067 (8)0.0028 (8)
O1W0.0330 (9)0.0613 (12)0.0486 (16)0.0163 (8)0.0057 (8)0.0157 (10)
O20.0241 (8)0.0512 (11)0.0347 (13)0.0028 (8)0.0018 (7)0.0157 (10)
O2W0.0439 (10)0.0700 (16)0.0276 (12)0.0251 (10)0.0055 (9)0.0087 (10)
O30.0294 (8)0.0350 (9)0.0210 (10)0.0072 (7)0.0016 (7)0.0082 (8)
O40.0346 (8)0.0295 (9)0.0222 (9)0.0048 (7)0.0009 (6)0.0027 (7)
O50.0289 (6)0.0320 (8)0.0226 (9)0.0002 (6)0.0016 (7)0.0006 (8)
C10.0382 (13)0.0283 (12)0.0307 (16)0.0052 (10)0.0037 (11)0.0056 (12)
C20.0594 (19)0.0329 (15)0.0451 (19)0.0131 (12)0.0053 (14)0.0066 (14)
C30.0381 (14)0.0525 (17)0.0358 (18)0.0196 (12)0.0025 (12)0.0060 (13)
C40.0240 (10)0.0346 (13)0.0267 (14)0.0013 (9)0.0013 (9)0.0051 (11)
C50.0227 (9)0.0287 (13)0.0211 (13)0.0014 (9)0.0027 (8)0.0002 (10)
C60.0322 (10)0.0243 (12)0.0242 (13)0.0040 (9)0.0004 (10)0.0038 (11)
C70.0254 (10)0.0273 (12)0.0277 (14)0.0076 (9)0.0022 (10)0.0022 (11)
C80.0134 (8)0.0285 (12)0.0245 (14)0.0024 (8)0.0014 (8)0.0003 (10)
Geometric parameters (Å, º) top
Cu1—O3i1.9313 (16)C1—C21.528 (4)
Cu1—O21.9524 (17)C1—C61.535 (4)
Cu1—O2W1.990 (2)C1—H1A0.9800
Cu1—O42.0542 (19)C2—C31.540 (4)
Cu1—O52.3147 (14)C2—H2A0.9700
Cu1—O1W2.3726 (19)C2—H2B0.9700
O1—C71.240 (3)C3—C41.521 (3)
O1W—H1WA0.842 (17)C3—H3A0.9700
O1W—H1WB0.852 (17)C3—H3B0.9700
O2—C71.264 (3)C4—C51.533 (3)
O2W—H2WA0.871 (17)C4—H4A0.9800
O2W—H2WB0.795 (18)C5—C81.514 (3)
O3—C81.249 (3)C5—C61.578 (3)
O3—Cu1ii1.9313 (16)C5—H5A0.9800
O4—C81.253 (3)C6—C71.536 (3)
O5—C11.450 (3)C6—H6A0.9800
O5—C41.454 (3)
O3i—Cu1—O2171.25 (8)C3—C2—H2A111.5
O3i—Cu1—O2W95.92 (9)C1—C2—H2B111.5
O2—Cu1—O2W87.90 (8)C3—C2—H2B111.5
O3i—Cu1—O489.15 (7)H2A—C2—H2B109.3
O2—Cu1—O487.30 (8)C4—C3—C2101.87 (19)
O2W—Cu1—O4174.69 (8)C4—C3—H3A111.4
O3i—Cu1—O599.62 (6)C2—C3—H3A111.4
O2—Cu1—O588.19 (7)C4—C3—H3B111.4
O2W—Cu1—O590.51 (9)C2—C3—H3B111.4
O4—Cu1—O587.07 (6)H3A—C3—H3B109.3
O3i—Cu1—O1W82.43 (8)O5—C4—C3102.49 (19)
O2—Cu1—O1W89.03 (8)O5—C4—C5102.70 (16)
O2W—Cu1—O1W103.70 (9)C3—C4—C5109.4 (2)
O4—Cu1—O1W78.49 (7)O5—C4—H4A113.7
O5—Cu1—O1W165.41 (8)C3—C4—H4A113.7
Cu1—O1W—H1WA121 (2)C5—C4—H4A113.7
Cu1—O1W—H1WB135 (2)C8—C5—C4113.6 (2)
H1WA—O1W—H1WB99 (2)C8—C5—C6112.40 (17)
C7—O2—Cu1126.29 (15)C4—C5—C6100.98 (19)
Cu1—O2W—H2WA128 (3)C8—C5—H5A109.9
Cu1—O2W—H2WB120 (3)C4—C5—H5A109.9
H2WA—O2W—H2WB102 (2)C6—C5—H5A109.9
C8—O3—Cu1ii132.82 (15)C1—C6—C7112.9 (2)
C8—O4—Cu1124.31 (15)C1—C6—C5100.79 (19)
C1—O5—C495.93 (17)C7—C6—C5113.56 (18)
C1—O5—Cu1111.39 (12)C1—C6—H6A109.7
C4—O5—Cu1112.98 (13)C7—C6—H6A109.7
O5—C1—C2102.40 (19)C5—C6—H6A109.7
O5—C1—C6102.60 (18)O1—C7—O2123.0 (2)
C2—C1—C6110.0 (2)O1—C7—C6118.9 (2)
O5—C1—H1A113.6O2—C7—C6118.1 (2)
C2—C1—H1A113.6O3—C8—O4124.0 (2)
C6—C1—H1A113.6O3—C8—C5116.3 (2)
C1—C2—C3101.5 (2)O4—C8—C5119.7 (2)
C1—C2—H2A111.5
O2W—Cu1—O2—C7131.2 (2)C2—C3—C4—O534.5 (2)
O4—Cu1—O2—C746.5 (2)C2—C3—C4—C574.0 (3)
O5—Cu1—O2—C740.6 (2)O5—C4—C5—C886.0 (2)
O1W—Cu1—O2—C7125.0 (2)C3—C4—C5—C8165.65 (19)
O3i—Cu1—O4—C8139.29 (16)O5—C4—C5—C634.5 (2)
O2—Cu1—O4—C848.70 (17)C3—C4—C5—C673.8 (2)
O5—Cu1—O4—C839.62 (16)O5—C1—C6—C785.9 (2)
O1W—Cu1—O4—C8138.26 (17)C2—C1—C6—C7165.7 (2)
O3i—Cu1—O5—C1174.10 (15)O5—C1—C6—C535.6 (2)
O2—Cu1—O5—C19.87 (16)C2—C1—C6—C572.8 (2)
O2W—Cu1—O5—C178.01 (16)C8—C5—C6—C1122.0 (2)
O4—Cu1—O5—C197.26 (16)C4—C5—C6—C10.6 (2)
O1W—Cu1—O5—C189.0 (3)C8—C5—C6—C70.9 (3)
O3i—Cu1—O5—C479.25 (15)C4—C5—C6—C7120.5 (2)
O2—Cu1—O5—C496.78 (15)Cu1—O2—C7—O1148.85 (19)
O2W—Cu1—O5—C4175.34 (15)Cu1—O2—C7—C631.8 (3)
O4—Cu1—O5—C49.39 (14)C1—C6—C7—O1142.1 (2)
O1W—Cu1—O5—C417.7 (3)C5—C6—C7—O1104.0 (3)
C4—O5—C1—C256.4 (2)C1—C6—C7—O237.3 (3)
Cu1—O5—C1—C2173.91 (15)C5—C6—C7—O276.7 (3)
C4—O5—C1—C657.6 (2)Cu1ii—O3—C8—O425.2 (3)
Cu1—O5—C1—C659.9 (2)Cu1ii—O3—C8—C5154.10 (15)
O5—C1—C2—C334.9 (3)Cu1—O4—C8—O3148.71 (18)
C6—C1—C2—C373.6 (3)Cu1—O4—C8—C530.6 (2)
C1—C2—C3—C40.2 (3)C4—C5—C8—O3142.9 (2)
C1—O5—C4—C356.3 (2)C6—C5—C8—O3103.2 (2)
Cu1—O5—C4—C3172.55 (15)C4—C5—C8—O437.8 (3)
C1—O5—C4—C557.25 (19)C6—C5—C8—O476.1 (3)
Cu1—O5—C4—C559.00 (19)
Symmetry codes: (i) x, y, z1/2; (ii) x, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WA···O1i0.84 (2)2.05 (2)2.835 (3)154 (4)
O1W—H1WB···O2iii0.85 (2)1.91 (2)2.731 (2)161 (3)
O2W—H2WA···O1iv0.87 (2)2.00 (2)2.870 (2)175 (3)
O2W—H2WB···O1Wi0.80 (2)2.21 (3)2.920 (3)148 (3)
O2W—H2WB···O4i0.80 (2)2.20 (3)2.780 (3)130 (3)
Symmetry codes: (i) x, y, z1/2; (iii) x, y, z; (iv) x, y, z1/2.

Experimental details

Crystal data
Chemical formula[Cu(C8H8O5)(H2O)2]
Mr283.72
Crystal system, space groupOrthorhombic, Iba2
Temperature (K)296
a, b, c (Å)10.5512 (4), 19.3389 (9), 9.7435 (4)
V3)1988.15 (14)
Z8
Radiation typeMo Kα
µ (mm1)2.22
Crystal size (mm)0.29 × 0.20 × 0.12
Data collection
DiffractometerBruker APEXII area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.60, 0.78
No. of measured, independent and
observed [I > 2σ(I)] reflections
7372, 2078, 1897
Rint0.021
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.022, 0.059, 1.02
No. of reflections2078
No. of parameters157
No. of restraints9
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.32, 0.38
Absolute structureFlack (1983), 857 Freidel pairs
Absolute structure parameter0.001 (16)

Computer programs: SMART (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WA···O1i0.842 (17)2.05 (2)2.835 (3)154 (4)
O1W—H1WB···O2ii0.852 (17)1.91 (2)2.731 (2)161 (3)
O2W—H2WA···O1iii0.871 (17)2.001 (18)2.870 (2)175 (3)
O2W—H2WB···O1Wi0.795 (18)2.21 (3)2.920 (3)148 (3)
O2W—H2WB···O4i0.795 (18)2.20 (3)2.780 (3)130 (3)
Symmetry codes: (i) x, y, z1/2; (ii) x, y, z; (iii) x, y, z1/2.
 

Acknowledgements

The authors acknowledge financial support from the Natural Science Foundation of Zhejiang Province, China (grant No. Y407301).

References

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First citationYin, F.-L., Shen, J., Zou, J.-J. & Li, R.-C. (2003). Acta Chim. Sin. 61, 556–561.  CAS Google Scholar

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