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Acta Cryst. (2012). E68, m1516-m1517    [ doi:10.1107/S1600536812047034 ]

Bis([mu]-2-carboxymethyl-2-hydroxybutanedioato)bis[diaquamanganese(II)]-1,2-bis(pyridin-4-yl)ethene-water (1/1/2)

I. H. Hwang, P.-G. Kim, J.-C. Lee, C. Kim and Y. Kim

Abstract top

The asymmetric unit of the title compound, [Mn2(C6H6O7)2(H2O)4]·C12H10N2·2H2O, contains half of the centrosymmetric Mn complex dimer, half of a 1,2-bis(pyridin-4-yl)ethene molecule, which lies across an inversion center, and one water molecule. Two citrate ligands bridge two MnII ions, and each MnII atom is coordinated by four O atoms from the citrate ligands (one from hydroxy and three from carboxylate groups) and two water O atoms, forming a distorted octahedral environment. In the crystal, O-H...O and O-H...N hydrogen bonds link the centrosymmetric dimers and lattice water molecules into a three-dimensional structure which is further stabilized by intermolecular [pi]-[pi] interactions [centroid-centroid distance = 3.959 (2) Å]. Weak C-H...O hydrogen bonding interactions are also observed.

Comment top

Complexes involving citric acid have often been used as models to examine the interaction between transition metal ions with biologically active molecules (Daniele et al., 2008; Parkin, 2004; Tshuva & Lippard, 2004; Stoumpos et al., 2009). Quite recently, our group has reported two novel compounds from the reaction of manganese(II) and zinc(II) nitrates as the building blocks and citric acid as the ligand (Hwang, et al., 2012a,b). In order to study the effects of spacer ligands on the interaction between transition metal ions with citric acid (Yu, et al., 2009; Kim, et al., 2011), in this work, we have attempted to employ 1,2-bis(4-pyridyl)ethene as a spacer source. We report here the resulting structure in which the 1,2-bis(4-pyridyl)ethene molecule does not function as a spacer but co-crystallises with the Mn complex to form bis(µ-2-carboxymethyl-2-hydroxybutanedioato)bis[diaquamanganese(II)]– 1,2-bis(pyridin-4-yl)ethene–water(1/1/2).

The molecular structure of the title compound is shown in Fig. 1. The asymmetric unit of the title compound, C24H34Mn2N2O20, contains half of the centrosymmetric Mn complex dimer, half of a 1,2-bis(pyridin-4-yl)ethene molecule, which lies across an inversion center, and one water molecule. Two citrate ligands bridge two MnII ions, and each MnII is coordinated by four oxygen atoms from the citrate ligands (one hydroxyl and three carboxylate, with one bridging) and two water oxygen atoms, forming a distorted octahedral environment. In the crystal, O—H···O hydrogen bonds link the centrosymmetric dimers and lattice water molecules into a three-dimensional structure. The crystal structure is further stabilized by intermolecular π-π interactions [centroid = C11–C15/N11; centroid–centroid distance = 3.959 (2) Å symmetry code: 1 - x, 2 - y, z].

Related literature top

For interactions of metal ions with biologically active molecules, see: Daniele et al. (2008); Parkin (2004); Tshuva & Lippard (2004); Stoumpos et al. (2009). For manganese citrate and zinc citrate complexes, see: Hwang, et al. (2012a,b). For related complexes, see: Yu et al. (2009); Kim et al. (2011).

Experimental top

Citric acid (19.4 mg, 0.1 mmol) and Zn(NO3)2.6H2O (30.4 mg, 0.1 mmol) were dissolved in 4 ml H2O and carefully layered by 4 ml of an acetonitrile solution of 1,2-bis(4-pyridyl)ethene (37.6 mg, 0.2 mmol). Suitable crystals of the title compound were obtained from this solution within two weeks.

Refinement top

H atoms bound to C were placed in calculated positions with C—H distances of 0.95 Å for aromatic C atoms and 0.99 Å for methylene C atoms. They were included in the refinement using the riding-motion approximation with Uiso(H) = 1.2Ueq(C). H atoms bound to O were located in difference Fourier maps and refined with their O–H distances restrained as follows and Uiso(H) = 1.2Ueq(O). Hydroxyl O—H = 0.860 (2) Å, coordinated water molecules O—H = 0.930 (2) Å the free water molecule O—H = 0.930 (2) Å.

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); 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).

Figures top
[Figure 1] Fig. 1. The structure of the title compound showing the atom numbering scheme. Displacement ellipsoids are shown at the 50% probability level. The labelled atoms are related to unlabelled atoms by the symmetry codes: [1 - x, 1 - y, 1 - z] for diaqua-bis-(citrato)di-manganese(II) complex and [2 - x, 2 - y,z] for the 1,2-bis(pyridin-4-yl)ethene molecule.
Bis(µ-2-carboxymethyl-2-hydroxybutanedioato)bis[diaquamanganese(II)]– 1,2-bis(pyridin-4-yl)ethene–water (1/1/2) top
Crystal data top
[Mn2(C6H6O7)2(H2O)4]·C12H10N2·2H2OZ = 1
Mr = 780.41F(000) = 402
Triclinic, P1Dx = 1.676 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 9.3970 (19) ÅCell parameters from 11909 reflections
b = 9.4580 (19) Åθ = 2.7–27.6°
c = 10.131 (2) ŵ = 0.91 mm−1
α = 70.24 (3)°T = 170 K
β = 67.11 (3)°Plate, colorless
γ = 75.52 (3)°0.15 × 0.10 × 0.02 mm
V = 773.3 (3) Å3
Data collection top
Bruker SMART CCD
diffractometer		2973 independent reflections
Radiation source: fine-focus sealed tube2423 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.021
φ and ω scansθmax = 26.0°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 1997)		h = −11→10
Tmin = 0.876, Tmax = 0.982k = −11→10
4358 measured reflectionsl = −12→12
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.038Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.098H atoms treated by a mixture of independent and constrained refinement
S = 1.08 w = 1/[σ2(Fo2) + (0.0538P)2]
where P = (Fo2 + 2Fc2)/3
2973 reflections(Δ/σ)max = 0.001
241 parametersΔρmax = 0.47 e Å−3
8 restraintsΔρmin = −0.63 e Å−3
Crystal data top
[Mn2(C6H6O7)2(H2O)4]·C12H10N2·2H2Oγ = 75.52 (3)°
Mr = 780.41V = 773.3 (3) Å3
Triclinic, P1Z = 1
a = 9.3970 (19) ÅMo Kα radiation
b = 9.4580 (19) ŵ = 0.91 mm−1
c = 10.131 (2) ÅT = 170 K
α = 70.24 (3)°0.15 × 0.10 × 0.02 mm
β = 67.11 (3)°
Data collection top
Bruker SMART CCD
diffractometer		2973 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 1997)		2423 reflections with I > 2σ(I)
Tmin = 0.876, Tmax = 0.982Rint = 0.021
4358 measured reflectionsθmax = 26.0°
Refinement top
R[F2 > 2σ(F2)] = 0.038H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.098Δρmax = 0.47 e Å−3
S = 1.08Δρmin = −0.63 e Å−3
2973 reflectionsAbsolute structure: ?
241 parametersFlack parameter: ?
8 restraintsRogers parameter: ?
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
Mn10.59596 (4)0.68914 (4)0.60932 (4)0.01775 (14)
O10.4231 (2)0.51640 (19)0.72246 (19)0.0179 (4)
H1O0.435 (3)0.479 (3)0.652 (2)0.021*
O20.3899 (2)0.79755 (19)0.54416 (19)0.0226 (4)
O30.1299 (2)0.8203 (2)0.6391 (2)0.0306 (5)
O40.4605 (2)0.7549 (2)0.81346 (19)0.0248 (4)
O50.3362 (2)0.6926 (2)1.0561 (2)0.0289 (5)
H5O0.411 (2)0.731 (3)1.055 (3)0.035*
O60.3225 (2)0.4206 (2)0.56485 (19)0.0232 (4)
O70.0686 (2)0.4237 (2)0.6196 (2)0.0335 (5)
O80.7614 (2)0.5543 (2)0.7192 (2)0.0263 (4)
H8A0.8656 (9)0.526 (3)0.669 (3)0.032*
H8B0.736 (3)0.4655 (17)0.794 (2)0.032*
O90.7071 (2)0.8889 (2)0.5139 (2)0.0311 (5)
H9A0.8153 (4)0.881 (3)0.478 (3)0.037*
H9B0.671 (3)0.9920 (8)0.501 (3)0.037*
C10.2687 (3)0.6001 (3)0.7591 (3)0.0166 (5)
C20.2613 (3)0.7522 (3)0.6372 (3)0.0187 (5)
C30.2331 (3)0.6280 (3)0.9100 (3)0.0209 (6)
H3A0.13280.69570.93200.025*
H3B0.21830.52990.98710.025*
C40.3533 (3)0.6963 (3)0.9249 (3)0.0195 (5)
C50.1477 (3)0.5074 (3)0.7752 (3)0.0184 (5)
H5A0.14110.41990.86420.022*
H5B0.04470.57130.79340.022*
C60.1791 (3)0.4481 (3)0.6430 (3)0.0188 (5)
N110.5629 (3)0.8142 (2)0.0477 (2)0.0236 (5)
C140.6748 (3)0.8996 (3)0.1754 (3)0.0234 (6)
H140.66730.91970.26380.028*
C110.6896 (3)0.8400 (3)−0.0763 (3)0.0257 (6)
H110.69310.8193−0.16300.031*
C120.8134 (3)0.8954 (3)−0.0799 (3)0.0247 (6)
H120.90150.9128−0.16790.030*
C130.8076 (3)0.9261 (3)0.0493 (3)0.0216 (6)
C150.5544 (3)0.8440 (3)0.1713 (3)0.0244 (6)
H150.46410.82670.25720.029*
C160.9369 (3)0.9793 (3)0.0573 (3)0.0246 (6)
H160.92990.98450.15170.030*
O1W0.0209 (3)0.8324 (2)0.4096 (3)0.0387 (5)
H1WA0.030 (4)0.7316 (11)0.412 (4)0.046*
H1WB0.063 (4)0.826 (4)0.481 (3)0.046*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Mn10.0180 (2)0.0188 (2)0.0175 (2)−0.00517 (15)−0.00514 (16)−0.00525 (16)
O10.0186 (9)0.0177 (9)0.0194 (9)−0.0028 (7)−0.0062 (8)−0.0075 (7)
O20.0221 (10)0.0213 (9)0.0203 (10)−0.0057 (8)−0.0052 (8)−0.0009 (7)
O30.0199 (10)0.0247 (10)0.0401 (12)0.0003 (8)−0.0103 (9)−0.0022 (9)
O40.0250 (10)0.0303 (10)0.0222 (10)−0.0116 (8)−0.0026 (8)−0.0114 (8)
O50.0301 (11)0.0424 (12)0.0210 (10)−0.0210 (9)−0.0075 (9)−0.0063 (9)
O60.0178 (9)0.0307 (10)0.0245 (10)−0.0041 (8)−0.0045 (8)−0.0140 (8)
O70.0228 (11)0.0514 (13)0.0378 (12)−0.0080 (9)−0.0096 (9)−0.0246 (10)
O80.0207 (10)0.0309 (11)0.0215 (10)−0.0038 (8)−0.0063 (8)−0.0008 (8)
O90.0248 (11)0.0189 (10)0.0454 (13)−0.0073 (8)−0.0074 (9)−0.0057 (9)
C10.0137 (12)0.0181 (12)0.0174 (13)−0.0044 (10)−0.0024 (10)−0.0057 (10)
C20.0184 (14)0.0182 (13)0.0219 (14)−0.0024 (11)−0.0080 (11)−0.0071 (11)
C30.0206 (14)0.0245 (14)0.0181 (13)−0.0066 (11)−0.0039 (11)−0.0067 (11)
C40.0196 (13)0.0184 (13)0.0213 (14)−0.0009 (10)−0.0071 (11)−0.0073 (11)
C50.0151 (13)0.0188 (13)0.0196 (13)−0.0048 (10)−0.0021 (10)−0.0056 (10)
C60.0175 (13)0.0183 (13)0.0209 (13)−0.0072 (10)−0.0055 (11)−0.0033 (10)
N110.0260 (13)0.0213 (11)0.0242 (12)−0.0056 (10)−0.0111 (10)−0.0022 (10)
C140.0304 (15)0.0202 (13)0.0228 (14)−0.0049 (11)−0.0129 (12)−0.0040 (11)
C110.0301 (15)0.0269 (15)0.0251 (15)−0.0054 (12)−0.0121 (12)−0.0086 (12)
C120.0240 (15)0.0284 (15)0.0246 (15)−0.0045 (12)−0.0090 (12)−0.0088 (12)
C130.0226 (14)0.0166 (13)0.0289 (15)−0.0038 (11)−0.0126 (12)−0.0048 (11)
C150.0266 (15)0.0223 (14)0.0243 (14)−0.0057 (11)−0.0096 (12)−0.0033 (11)
C160.0301 (16)0.0252 (14)0.0241 (14)−0.0057 (12)−0.0133 (12)−0.0071 (12)
O1W0.0384 (13)0.0336 (12)0.0503 (14)−0.0040 (10)−0.0209 (11)−0.0123 (11)
Geometric parameters (Å, º) top
Mn1—O92.136 (2)C1—C21.554 (3)
Mn1—O6i2.1373 (18)C3—C41.510 (3)
Mn1—O82.163 (2)C3—H3A0.9900
Mn1—O42.1701 (19)C3—H3B0.9900
Mn1—O22.1864 (19)C5—C61.521 (3)
Mn1—O12.288 (2)C5—H5A0.9900
O1—C11.440 (3)C5—H5B0.9900
O1—H1O0.860 (2)N11—C151.342 (3)
O2—C21.278 (3)N11—C111.352 (4)
O3—C21.238 (3)C14—C151.381 (4)
O4—C41.252 (3)C14—C131.397 (4)
O5—C41.264 (3)C14—H140.9500
O5—H5O0.861 (2)C11—C121.373 (4)
O6—C61.282 (3)C11—H110.9500
O6—Mn1i2.1372 (18)C12—C131.412 (4)
O7—C61.239 (3)C12—H120.9500
O8—H8A0.929 (2)C13—C161.465 (4)
O8—H8B0.930 (2)C15—H150.9500
O9—H9A0.930 (2)C16—C16ii1.328 (5)
O9—H9B0.930 (2)C16—H160.9500
C1—C51.532 (3)O1W—H1WA0.930 (2)
C1—C31.533 (3)O1W—H1WB0.930 (2)
O9—Mn1—O6i104.69 (8)C4—C3—H3A108.1
O9—Mn1—O895.79 (8)C1—C3—H3A108.1
O6i—Mn1—O895.74 (7)C4—C3—H3B108.1
O9—Mn1—O491.93 (8)C1—C3—H3B108.1
O6i—Mn1—O4162.66 (7)H3A—C3—H3B107.3
O8—Mn1—O487.30 (8)O4—C4—O5122.9 (2)
O9—Mn1—O294.80 (8)O4—C4—C3121.5 (2)
O6i—Mn1—O289.16 (7)O5—C4—C3115.6 (2)
O8—Mn1—O2166.80 (7)C6—C5—C1115.7 (2)
O4—Mn1—O284.48 (7)C6—C5—H5A108.4
O9—Mn1—O1166.09 (7)C1—C5—H5A108.4
O6i—Mn1—O183.34 (7)C6—C5—H5B108.4
O8—Mn1—O194.66 (7)C1—C5—H5B108.4
O4—Mn1—O179.39 (7)H5A—C5—H5B107.4
O2—Mn1—O173.70 (7)O7—C6—O6123.8 (2)
C1—O1—Mn1107.29 (13)O7—C6—C5119.6 (2)
C1—O1—H1O107.4 (18)O6—C6—C5116.5 (2)
Mn1—O1—H1O103.0 (18)C15—N11—C11120.3 (2)
C2—O2—Mn1115.41 (15)C15—C14—C13119.9 (2)
C4—O4—Mn1130.73 (16)C15—C14—H14120.1
C4—O5—H5O109 (2)C13—C14—H14120.1
C6—O6—Mn1i124.98 (16)N11—C11—C12121.7 (2)
Mn1—O8—H8A123.5 (18)N11—C11—H11119.2
Mn1—O8—H8B120.1 (18)C12—C11—H11119.2
H8A—O8—H8B102 (2)C11—C12—C13119.0 (3)
Mn1—O9—H9A120.1 (18)C11—C12—H12120.5
Mn1—O9—H9B134.0 (19)C13—C12—H12120.5
H9A—O9—H9B106 (3)C14—C13—C12118.2 (2)
O1—C1—C5110.87 (18)C14—C13—C16119.2 (2)
O1—C1—C3106.59 (19)C12—C13—C16122.6 (2)
C5—C1—C3108.3 (2)N11—C15—C14121.0 (3)
O1—C1—C2110.49 (19)N11—C15—H15119.5
C5—C1—C2109.4 (2)C14—C15—H15119.5
C3—C1—C2111.13 (19)C16ii—C16—C13124.9 (3)
O3—C2—O2125.2 (2)C16ii—C16—H16117.5
O3—C2—C1116.8 (2)C13—C16—H16117.5
O2—C2—C1118.0 (2)H1WA—O1W—H1WB103 (3)
C4—C3—C1116.8 (2)
O9—Mn1—O1—C11.5 (4)C3—C1—C2—O2103.5 (2)
O6i—Mn1—O1—C1−124.70 (14)O1—C1—C3—C451.3 (3)
O8—Mn1—O1—C1140.04 (14)C5—C1—C3—C4170.7 (2)
O4—Mn1—O1—C153.67 (14)C2—C1—C3—C4−69.1 (3)
O2—Mn1—O1—C1−33.63 (13)Mn1—O4—C4—O5144.1 (2)
O9—Mn1—O2—C2−144.09 (17)Mn1—O4—C4—C3−37.3 (3)
O6i—Mn1—O2—C2111.24 (17)C1—C3—C4—O413.8 (4)
O8—Mn1—O2—C2−0.8 (4)C1—C3—C4—O5−167.5 (2)
O4—Mn1—O2—C2−52.61 (17)O1—C1—C5—C6−54.3 (3)
O1—Mn1—O2—C227.93 (16)C3—C1—C5—C6−171.0 (2)
O9—Mn1—O4—C4173.5 (2)C2—C1—C5—C667.8 (3)
O6i—Mn1—O4—C49.9 (4)Mn1i—O6—C6—O7−5.4 (4)
O8—Mn1—O4—C4−90.8 (2)Mn1i—O6—C6—C5171.83 (15)
O2—Mn1—O4—C478.9 (2)C1—C5—C6—O7−153.2 (2)
O1—Mn1—O4—C44.5 (2)C1—C5—C6—O629.4 (3)
Mn1—O1—C1—C5156.94 (15)C15—N11—C11—C120.7 (4)
Mn1—O1—C1—C3−85.35 (18)N11—C11—C12—C13−0.1 (4)
Mn1—O1—C1—C235.5 (2)C15—C14—C13—C120.3 (4)
Mn1—O2—C2—O3162.7 (2)C15—C14—C13—C16−177.6 (2)
Mn1—O2—C2—C1−16.8 (3)C11—C12—C13—C14−0.4 (4)
O1—C1—C2—O3165.9 (2)C11—C12—C13—C16177.4 (2)
C5—C1—C2—O343.6 (3)C11—N11—C15—C14−0.8 (4)
C3—C1—C2—O3−76.0 (3)C13—C14—C15—N110.3 (4)
O1—C1—C2—O2−14.6 (3)C14—C13—C16—C16ii−174.0 (3)
C5—C1—C2—O2−136.9 (2)C12—C13—C16—C16ii8.2 (5)
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x+2, −y+2, −z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C12—H12···O3iii0.952.483.344 (4)151
C11—H11···O4iv0.952.533.143 (3)123
O9—H9B···O3v0.93 (1)2.56 (3)3.113 (3)118 (2)
O9—H9B···O2v0.93 (1)1.88 (1)2.803 (3)175 (3)
O9—H9A···O1Wvi0.93 (1)1.78 (1)2.695 (3)170 (3)
O8—H8B···O5vii0.93 (1)1.78 (1)2.707 (3)173 (3)
O8—H8A···O7vi0.93 (1)1.87 (1)2.769 (3)163 (3)
O5—H5O···N11viii0.86 (1)1.76 (1)2.625 (3)178 (3)
O1W—H1WB···O30.93 (1)1.92 (1)2.843 (3)175 (3)
O1—H1O···O60.86 (1)1.88 (2)2.616 (2)143 (2)
O1W—H1WA···O7ix0.93 (1)2.08 (2)2.891 (3)145 (3)
Symmetry codes: (iii) x+1, y, z−1; (iv) x, y, z−1; (v) −x+1, −y+2, −z+1; (vi) x+1, y, z; (vii) −x+1, −y+1, −z+2; (viii) x, y, z+1; (ix) −x, −y+1, −z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C12—H12···O3i0.952.483.344 (4)151.3
C11—H11···O4ii0.952.533.143 (3)122.8
O9—H9B···O3iii0.930 (2)2.56 (3)3.113 (3)118 (2)
O9—H9B···O2iii0.930 (2)1.876 (4)2.803 (3)175 (3)
O9—H9A···O1Wiv0.930 (2)1.776 (6)2.695 (3)170 (3)
O8—H8B···O5v0.930 (2)1.782 (5)2.707 (3)173 (3)
O8—H8A···O7iv0.929 (2)1.868 (9)2.769 (3)163 (3)
O5—H5O···N11vi0.861 (2)1.764 (4)2.625 (3)178 (3)
O1W—H1WB···O30.930 (2)1.916 (5)2.843 (3)175 (3)
O1—H1O···O60.860 (2)1.880 (17)2.616 (2)143 (2)
O1W—H1WA···O7vii0.930 (2)2.082 (19)2.891 (3)145 (3)
Symmetry codes: (i) x+1, y, z−1; (ii) x, y, z−1; (iii) −x+1, −y+2, −z+1; (iv) x+1, y, z; (v) −x+1, −y+1, −z+2; (vi) x, y, z+1; (vii) −x, −y+1, −z+1.
Acknowledgements top

Financial support from Forest Science & Technology Projects (S121012L080111) and the Converging Research Center Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2012001725) is gratefully acknowledged.

references
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