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Acta Crystallogr Sect E Struct Rep Online. 2009 January 1; 65(Pt 1): o61.
Published online 2008 December 10. doi:  10.1107/S1600536808038816
PMCID: PMC2967974

1-(Phthalimidometh­yl)pyridinium p-toluene­sulfonate

Abstract

In the crystal of the title compound, C14H11N2O2 +·C7H7O3S, the cation and anion inter­act by way of an aromatic π–π inter­action [centroid–centroid separation = 3.5783 (2) Å] and a T-stacking (C—H(...)π) inter­action between cations. The dihedral angle between the aromatic rings in the cation is 61.73 (8)°. The ionic units are aligned in a zigzag fashion in the b-axis direction.

Related literature

For medicinal background, see: Al-Madhoun et al. (2002 [triangle]); Arner & Eriksson (1995 [triangle]); Bello (1974 [triangle]); Celen et al. (2007 [triangle]); Eriksson et al. (2002 [triangle]); Wei et al. (2005 [triangle]); Welin et al. (2004 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-00o61-scheme1.jpg

Experimental

Crystal data

  • C14H11N2O2 +·C7H7O3S
  • M r = 410.43
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-00o61-efi1.jpg
  • a = 7.6944 (5) Å
  • b = 33.626 (2) Å
  • c = 7.9426 (5) Å
  • β = 116.416 (1)°
  • V = 1840.5 (2) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.21 mm−1
  • T = 90 (2) K
  • 0.30 × 0.25 × 0.20 mm

Data collection

  • Bruker APEX CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 2008 [triangle]) T min = 0.939, T max = 0.958
  • 19080 measured reflections
  • 4482 independent reflections
  • 3753 reflections with I > 2σ(I)
  • R int = 0.049

Refinement

  • R[F 2 > 2σ(F 2)] = 0.054
  • wR(F 2) = 0.124
  • S = 1.12
  • 4482 reflections
  • 263 parameters
  • H-atom parameters constrained
  • Δρmax = 0.61 e Å−3
  • Δρmin = −0.38 e Å−3

Data collection: SMART (Bruker, 2002 [triangle]); cell refinement: SAINT (Bruker, 2002 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: DIAMOND (Brandenburg & Putz (1999 [triangle]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808038816/hb2840sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808038816/hb2840Isup2.hkl

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

Acknowledgments

The authors gratefully acknowledge the support of the National Science Foundation (CHE-0604527) and Molecular Insight Pharmaceuticals Inc.

supplementary crystallographic information

Comment

Radiolabeled nucleosides and nucleoside analogs may be good candidates for imaging and therapeutic applications because of their metabolic entrapment in rapidly dividing cells like tumor cells. These radiolabeled nucleoside derivatives may act as substrates for the human cytosolic thymidine kinase (hTK-1), an enzyme of the salvage pathway which catalyzes the phosphorylation of nucleosides to their corresponding 5'-monophosphates (Welin et al., 2004). The phosphorylation would mainly occur in proliferating tumor cells since hTK-1 shows a dramatically increased activity in tumor cells compared to quiescent cells (Bello, 1974). The phosphorylated nucleosides would be entrapped inside the proliferating cells because of their negatively charged phosphate moiety retarding the cellular efflux (Arner et al., 1995). Thus, a radiolabeled nucleoside analog could be used as probe for tumor cell proliferation since the entrapment results in an accumulation in tissue with elevated hTK-1 activity. The main problem for the development of a suitable nucleoside analog lies in the narrow substrate specifity of hTK-1 (Eriksson et al., 2002). The natural substrates for hTK-1 are thymidine and uridine. Major modifications of the corresponding nucleoside, however, may lead to a highly decreased activity. The literature on the interaction of thymidine derivatives with hTK-1 is not totally unambiguous about the effects of various substitutions. For example, N-3 derivatized thymidine analogs have been reported to be inactive (Celen et al., 2007). On the other hand, N-3 modified carboranylalkyl thymidine analogs show acceptable conversion rates (Al-Madhoun et al., 2002). Therefore, we made a set of several thymidine and uridine analogs modified at different positions of the ribose and the base moiety to get further insight on the effects of various derivatizations. To expand our SAAC concept (single amino acid chelate) for radioimaging and radiotherapeutic purposes on nucleosides, the title phthalimidomethylpyridinium p-toluenesulfonate salt, (I), was prepared as part of a series of tosylalkylphthalimide derivatives recently synthesized in our group. This series is used for the attachment of a SAAC chelate at the N-3 and C-5 position of the base moiety of thymidine (Bartholomä et al. unpublished results). The SAAC chelate allows hereby the radiolabelling of thymidine and uridine derivatives by the coordination of the [M(CO)3]+ core (M = 186/188Re, 99mTc) (Wei et al., 2005). The ideal decay properties, low cost and convenient availability of 99mTc from generator columns make the corresponding nucleoside complexes interesting candidates for imaging purposes while their corresponding rhenium complexes could be used as therapeutic counterparts.

Due to the tetrahedral arrangement of the connecting methyl group, the phthalimidomethylpyridinium cation in (I) is not planar. The tosylate anion sits on top of one end of the pyridinium residue showing aromatic π-π interaction. The centroid distance between those two aromatic rings is 3.5783 (2) Å. The other end of the pyridinium moiety shows some interaction with the phthalimide part of neighbored phthalimidomethyl-pyridinium cation. Thus, a T-stacking between the pyridinium residue and the benzyl ring of the phthalimide residue occurs (Table 1). The distances between the interacting C—H of the phthalimide and the centroid of the pyridinium residue are C2–Centroid = 3.5313 (2) Å and H2–Centroid = 2.70Å, respectively. The corresponding angle C2–H2···Centroid is 147°. The phthalimide moiety itself has a planar geometry. All bond length and angles fall in expected ranges. In the crystal, the ionic units are aligned in a zigzag arrangement in direction of the b axis.

Experimental

2.00 g (11.29 mmol) N-(Hydroxymethyl)phthalimide were dissolved in 20 ml anhydrous pyridine under an inert atmosphere followed by a dropwise addition of 3.23 g (16.93 mmol, 1.5 equiv.) p-Toluenesulfonyl chloride in 20 ml anhydrous pyridine. After complete addition of the tosylchloride, the reaction mixture was stirred for additional 16 h. About 2 h after the addition was completed, a white precipitate started to form. This white solid was filtered off, washed three times with 100 ml chloroform, and finally dried for several days at h.v.. The product was obtained in good yields as a colourless amorphous powder (3.80 g, quantitative); colourless blocks of (I) suitable for X-ray diffraction were collected directly from the reaction mixture. 1H NMR (d6-DMSO): δ = 2.28 (s, 3 H), 6.41 (s, 2 H), 7.10 (d, J = 7.98 Hz, 2 H), 7.47 (d, J = 7.95 Hz, 2 H), 7.90–7.99 (m, 4 H), 8.20 (t, J = 7.05 Hz, 2 H), 8.67 (t, J = 7.68 Hz, 1 H), 9.09 (d, J = 5.80 Hz, 2 H). p.p.m.. IR: ν = 3398 (br), 3124, 3087, 3037, 2980, 2935, 1781, 1729, 1627, 1485, 1404, 1361, 1331, 1300, 1268, 1206, 1168, 1116, 1089, 1067, 1031, 1008, 951, 826, 801, 777, 728, 680, 632, 587, 565, 529 cm-1.

Refinement

The H atoms were placed in calculated positions and refined as riding.

Figures

Fig. 1.
Perspective view of (I), with displacement ellipsoids drawn at 50% probability level (H atoms omitted for clarity).
Fig. 2.
Aromatic interactions observed within the crystal lattice of (I).
Fig. 3.
The crystal packing of (I) viewed parallel to the bc plane.

Crystal data

C14H11N2O2+·C7H7O3SF(000) = 856
Mr = 410.43Dx = 1.481 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3297 reflections
a = 7.6944 (5) Åθ = 2.4–26.4°
b = 33.626 (2) ŵ = 0.21 mm1
c = 7.9426 (5) ÅT = 90 K
β = 116.416 (1)°Block, colourless
V = 1840.5 (2) Å30.30 × 0.25 × 0.20 mm
Z = 4

Data collection

Bruker APEX CCD diffractometer4482 independent reflections
Radiation source: fine-focus sealed tube3753 reflections with I > 2σ(I)
graphiteRint = 0.049
Detector resolution: 512 pixels mm-1θmax = 28.1°, θmin = 2.4°
ω scansh = −10→10
Absorption correction: multi-scan (SADABS; Sheldrick, 2008)k = −42→44
Tmin = 0.939, Tmax = 0.958l = −10→10
19080 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.054Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.124H-atom parameters constrained
S = 1.12w = 1/[σ2(Fo2) + (0.0508P)2 + 1.1529P] where P = (Fo2 + 2Fc2)/3
4482 reflections(Δ/σ)max < 0.001
263 parametersΔρmax = 0.61 e Å3
0 restraintsΔρmin = −0.38 e Å3

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
S10.71561 (7)0.151380 (15)0.83629 (7)0.01495 (13)
O11.0063 (2)0.07297 (5)0.3896 (2)0.0232 (3)
O20.4402 (2)0.01341 (5)0.3092 (2)0.0247 (4)
O30.8408 (2)0.15516 (5)0.7439 (2)0.0209 (3)
O40.6566 (2)0.11048 (4)0.8427 (2)0.0232 (3)
O50.7929 (2)0.17090 (5)1.0188 (2)0.0217 (3)
N10.7117 (2)0.05127 (5)0.3668 (2)0.0173 (4)
N20.5370 (2)0.11140 (5)0.3597 (2)0.0158 (4)
C10.8823 (3)0.04795 (6)0.3432 (3)0.0169 (4)
C20.8696 (3)0.00828 (6)0.2554 (3)0.0159 (4)
C30.9997 (3)−0.01049 (6)0.2060 (3)0.0191 (4)
H31.11660.00200.22190.023*
C40.9513 (3)−0.04884 (7)0.1314 (3)0.0228 (5)
H41.0367−0.06280.09520.027*
C50.7805 (3)−0.06681 (7)0.1096 (3)0.0239 (5)
H50.7523−0.09300.05980.029*
C60.6488 (3)−0.04768 (7)0.1584 (3)0.0217 (4)
H60.5315−0.06010.14230.026*
C70.6972 (3)−0.00982 (6)0.2314 (3)0.0170 (4)
C80.5931 (3)0.01743 (6)0.3028 (3)0.0179 (4)
C90.6823 (3)0.08173 (6)0.4785 (3)0.0204 (4)
H9A0.80710.09530.55470.025*
H9B0.63790.06940.56570.025*
C100.3571 (3)0.11045 (6)0.3473 (3)0.0177 (4)
H100.32450.09100.41500.021*
C110.2198 (3)0.13761 (6)0.2367 (3)0.0182 (4)
H110.09170.13670.22570.022*
C120.2708 (3)0.16635 (6)0.1417 (3)0.0193 (4)
H120.17810.18550.06570.023*
C130.4584 (3)0.16703 (6)0.1581 (3)0.0192 (4)
H130.49520.18670.09420.023*
C140.5902 (3)0.13900 (6)0.2678 (3)0.0185 (4)
H140.71840.13900.27900.022*
C150.4978 (3)0.17744 (6)0.6922 (3)0.0147 (4)
C160.3230 (3)0.16559 (6)0.6887 (3)0.0170 (4)
H160.31960.14300.75910.020*
C170.1535 (3)0.18648 (6)0.5831 (3)0.0180 (4)
H170.03550.17830.58320.022*
C180.1543 (3)0.21947 (6)0.4764 (3)0.0169 (4)
C19−0.0316 (3)0.24117 (7)0.3577 (3)0.0221 (5)
H19A−0.00260.26520.30490.033*
H19B−0.09570.24860.43570.033*
H19C−0.11760.22380.25530.033*
C200.3304 (3)0.23071 (6)0.4797 (3)0.0184 (4)
H200.33360.25290.40690.022*
C210.5012 (3)0.21025 (6)0.5872 (3)0.0167 (4)
H210.61980.21860.58890.020*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
S10.0132 (2)0.0163 (2)0.0136 (2)−0.00043 (18)0.00446 (18)−0.00117 (18)
O10.0220 (8)0.0201 (8)0.0253 (8)−0.0060 (6)0.0086 (7)−0.0012 (6)
O20.0170 (7)0.0361 (9)0.0229 (8)−0.0006 (7)0.0105 (6)0.0016 (7)
O30.0184 (7)0.0250 (8)0.0212 (8)0.0008 (6)0.0106 (6)−0.0010 (6)
O40.0203 (8)0.0182 (8)0.0288 (8)−0.0001 (6)0.0087 (7)0.0030 (6)
O50.0183 (7)0.0290 (8)0.0130 (7)0.0020 (6)0.0027 (6)−0.0037 (6)
N10.0168 (8)0.0177 (9)0.0160 (8)0.0022 (7)0.0060 (7)0.0003 (7)
N20.0154 (8)0.0182 (8)0.0110 (8)0.0043 (7)0.0035 (7)−0.0007 (6)
C10.0165 (10)0.0187 (10)0.0135 (9)0.0029 (8)0.0049 (8)0.0032 (7)
C20.0181 (10)0.0150 (9)0.0120 (9)0.0015 (8)0.0044 (8)0.0032 (7)
C30.0207 (10)0.0221 (11)0.0144 (10)0.0022 (8)0.0077 (8)0.0034 (8)
C40.0315 (12)0.0237 (11)0.0137 (10)0.0088 (9)0.0105 (9)0.0037 (8)
C50.0371 (13)0.0169 (10)0.0133 (10)−0.0018 (9)0.0074 (9)0.0002 (8)
C60.0262 (11)0.0208 (11)0.0149 (10)−0.0056 (9)0.0063 (9)0.0012 (8)
C70.0158 (9)0.0192 (10)0.0132 (9)0.0000 (8)0.0041 (8)0.0036 (7)
C80.0167 (10)0.0220 (10)0.0119 (9)0.0004 (8)0.0036 (8)0.0047 (8)
C90.0212 (10)0.0241 (11)0.0129 (9)0.0076 (8)0.0047 (8)0.0020 (8)
C100.0193 (10)0.0194 (10)0.0144 (9)−0.0002 (8)0.0076 (8)−0.0026 (8)
C110.0148 (9)0.0223 (10)0.0149 (10)0.0009 (8)0.0044 (8)−0.0050 (8)
C120.0198 (10)0.0186 (10)0.0142 (10)0.0044 (8)0.0026 (8)−0.0026 (8)
C130.0247 (11)0.0171 (10)0.0152 (10)0.0006 (8)0.0083 (8)0.0006 (8)
C140.0177 (10)0.0207 (10)0.0163 (10)−0.0010 (8)0.0068 (8)−0.0031 (8)
C150.0139 (9)0.0166 (9)0.0102 (9)0.0000 (7)0.0022 (7)−0.0026 (7)
C160.0199 (10)0.0185 (10)0.0123 (9)−0.0001 (8)0.0068 (8)0.0001 (7)
C170.0163 (9)0.0213 (10)0.0158 (10)0.0002 (8)0.0067 (8)−0.0027 (8)
C180.0205 (10)0.0159 (9)0.0107 (9)0.0013 (8)0.0038 (8)−0.0042 (7)
C190.0207 (11)0.0228 (11)0.0184 (10)0.0049 (8)0.0047 (9)−0.0019 (8)
C200.0233 (10)0.0155 (10)0.0139 (9)−0.0002 (8)0.0061 (8)−0.0010 (7)
C210.0162 (9)0.0188 (10)0.0134 (9)−0.0037 (8)0.0050 (8)−0.0035 (7)

Geometric parameters (Å, °)

S1—O31.4531 (15)C9—H9B0.9900
S1—O51.4556 (15)C10—C111.377 (3)
S1—O41.4562 (16)C10—H100.9500
S1—C151.783 (2)C11—C121.386 (3)
O1—C11.201 (3)C11—H110.9500
O2—C81.208 (2)C12—C131.391 (3)
N1—C81.405 (3)C12—H120.9500
N1—C11.410 (3)C13—C141.375 (3)
N1—C91.437 (3)C13—H130.9500
N2—C101.343 (3)C14—H140.9500
N2—C141.352 (3)C15—C211.390 (3)
N2—C91.482 (3)C15—C161.391 (3)
C1—C21.488 (3)C16—C171.387 (3)
C2—C31.380 (3)C16—H160.9500
C2—C71.393 (3)C17—C181.397 (3)
C3—C41.399 (3)C17—H170.9500
C3—H30.9500C18—C201.396 (3)
C4—C51.386 (3)C18—C191.506 (3)
C4—H40.9500C19—H19A0.9800
C5—C61.393 (3)C19—H19B0.9800
C5—H50.9500C19—H19C0.9800
C6—C71.380 (3)C20—C211.390 (3)
C6—H60.9500C20—H200.9500
C7—C81.486 (3)C21—H210.9500
C9—H9A0.9900
O3—S1—O5113.25 (9)H9A—C9—H9B108.0
O3—S1—O4112.78 (9)N2—C10—C11120.30 (19)
O5—S1—O4112.75 (10)N2—C10—H10119.8
O3—S1—C15106.13 (9)C11—C10—H10119.8
O5—S1—C15105.58 (9)C10—C11—C12119.12 (19)
O4—S1—C15105.53 (9)C10—C11—H11120.4
C8—N1—C1112.38 (17)C12—C11—H11120.4
C8—N1—C9123.06 (18)C11—C12—C13119.60 (19)
C1—N1—C9123.35 (18)C11—C12—H12120.2
C10—N2—C14121.75 (18)C13—C12—H12120.2
C10—N2—C9119.46 (18)C14—C13—C12119.4 (2)
C14—N2—C9118.78 (17)C14—C13—H13120.3
O1—C1—N1124.31 (19)C12—C13—H13120.3
O1—C1—C2130.5 (2)N2—C14—C13119.82 (19)
N1—C1—C2105.22 (17)N2—C14—H14120.1
C3—C2—C7121.9 (2)C13—C14—H14120.1
C3—C2—C1129.71 (19)C21—C15—C16119.42 (18)
C7—C2—C1108.40 (18)C21—C15—S1120.78 (15)
C2—C3—C4116.9 (2)C16—C15—S1119.78 (15)
C2—C3—H3121.6C17—C16—C15120.50 (19)
C4—C3—H3121.6C17—C16—H16119.8
C5—C4—C3120.9 (2)C15—C16—H16119.8
C5—C4—H4119.5C16—C17—C18120.81 (19)
C3—C4—H4119.5C16—C17—H17119.6
C4—C5—C6122.1 (2)C18—C17—H17119.6
C4—C5—H5119.0C20—C18—C17118.02 (19)
C6—C5—H5119.0C20—C18—C19121.63 (19)
C7—C6—C5116.7 (2)C17—C18—C19120.33 (19)
C7—C6—H6121.7C18—C19—H19A109.5
C5—C6—H6121.7C18—C19—H19B109.5
C6—C7—C2121.6 (2)H19A—C19—H19B109.5
C6—C7—C8129.7 (2)C18—C19—H19C109.5
C2—C7—C8108.70 (18)H19A—C19—H19C109.5
O2—C8—N1124.3 (2)H19B—C19—H19C109.5
O2—C8—C7130.4 (2)C21—C20—C18121.47 (19)
N1—C8—C7105.31 (17)C21—C20—H20119.3
N1—C9—N2111.61 (16)C18—C20—H20119.3
N1—C9—H9A109.3C20—C21—C15119.78 (19)
N2—C9—H9A109.3C20—C21—H21120.1
N1—C9—H9B109.3C15—C21—H21120.1
N2—C9—H9B109.3
C8—N1—C1—O1−179.12 (19)C1—N1—C9—N2108.7 (2)
C9—N1—C1—O1−11.4 (3)C10—N2—C9—N1104.0 (2)
C8—N1—C1—C20.2 (2)C14—N2—C9—N1−76.5 (2)
C9—N1—C1—C2167.94 (17)C14—N2—C10—C111.0 (3)
O1—C1—C2—C30.9 (4)C9—N2—C10—C11−179.58 (18)
N1—C1—C2—C3−178.3 (2)N2—C10—C11—C12−1.3 (3)
O1—C1—C2—C7179.2 (2)C10—C11—C12—C130.6 (3)
N1—C1—C2—C7−0.1 (2)C11—C12—C13—C140.4 (3)
C7—C2—C3—C4−0.4 (3)C10—N2—C14—C130.0 (3)
C1—C2—C3—C4177.63 (19)C9—N2—C14—C13−179.44 (18)
C2—C3—C4—C5−0.2 (3)C12—C13—C14—N2−0.7 (3)
C3—C4—C5—C60.7 (3)O3—S1—C15—C21−30.90 (19)
C4—C5—C6—C7−0.5 (3)O5—S1—C15—C2189.57 (17)
C5—C6—C7—C2−0.2 (3)O4—S1—C15—C21−150.81 (16)
C5—C6—C7—C8−177.4 (2)O3—S1—C15—C16150.97 (16)
C3—C2—C7—C60.6 (3)O5—S1—C15—C16−88.55 (17)
C1—C2—C7—C6−177.78 (19)O4—S1—C15—C1631.06 (19)
C3—C2—C7—C8178.36 (18)C21—C15—C16—C17−0.7 (3)
C1—C2—C7—C8−0.1 (2)S1—C15—C16—C17177.49 (15)
C1—N1—C8—O2179.69 (19)C15—C16—C17—C180.8 (3)
C9—N1—C8—O211.9 (3)C16—C17—C18—C20−0.1 (3)
C1—N1—C8—C7−0.2 (2)C16—C17—C18—C19178.17 (19)
C9—N1—C8—C7−168.02 (17)C17—C18—C20—C21−0.8 (3)
C6—C7—C8—O2−2.3 (4)C19—C18—C20—C21−179.02 (19)
C2—C7—C8—O2−179.7 (2)C18—C20—C21—C151.0 (3)
C6—C7—C8—N1177.6 (2)C16—C15—C21—C20−0.2 (3)
C2—C7—C8—N10.2 (2)S1—C15—C21—C20−178.34 (15)
C8—N1—C9—N2−84.8 (2)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C5—H5···Cg1i0.952.703.531 (2)147

Symmetry codes: (i) −x+1, −y, −z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HB2840).

References

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