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ISSN: 2056-9890

(3R,4S)-1-(4-Meth­­oxy­phen­yl)-2-oxo-4-(3-vinyl­phen­yl)azetidin-3-yl acetate

aSchool of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai 201203, People's Republic of China
*Correspondence e-mail: sunxunf@shmu.edu.cn

(Received 24 January 2013; accepted 21 March 2013; online 28 March 2013)

In the title compound, C20H19NO4, the absolute configuration (3R,4S) for the two chiral centres of the mol­ecule has been determined.

Related literature

For the preparation of the title compound, an inter­mediate in the synthesis of C-4 to C-3′ bridged paclitaxel analogues, see: Ganesh et al. (2007[Ganesh, T., Yang, C., Norris, A., Glass, T., Bane, S., Ravindra, R., Banerjee, A., Metaferia, B., Thomas, S. L. & Giannakakou, P. (2007). J. Med. Chem. 50, 713-725.]).

[Scheme 1]

Experimental

Crystal data
  • C20H19NO4

  • Mr = 337.36

  • Monoclinic, C 2

  • a = 20.7448 (4) Å

  • b = 6.3930 (1) Å

  • c = 15.7434 (3) Å

  • β = 124.309 (1)°

  • V = 1724.64 (5) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 0.74 mm−1

  • T = 124 K

  • 0.20 × 0.18 × 0.11 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2010[Bruker (2010). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.866, Tmax = 0.923

  • 6072 measured reflections

  • 2374 independent reflections

  • 2330 reflections with I > 2σ(I)

  • Rint = 0.024

Refinement
  • R[F2 > 2σ(F2)] = 0.026

  • wR(F2) = 0.069

  • S = 1.06

  • 2374 reflections

  • 228 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.18 e Å−3

  • Δρmin = −0.15 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 730 Friedel pairs

  • Flack parameter: 0.01 (15)

Data collection: APEX2 (Bruker, 2010[Bruker (2010). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2010[Bruker (2010). APEX2, SAINT and SADABS. 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: SHELXTL.

Supporting information


Comment top

In our research on the conformation of a novel fluorinated, tubulin-bound, docetaxel analogue, one of the key intermediate products, the title compound (3R,4S)-1-(4-methoxyphenyl)-2-oxo-4-(3-vinylphenyl)azetidin-3-yl acetate C20H19NO4 (I) (Fig. 1) was separated from the racemic 1-(4-methoxyphenyl)-2-oxo-4-(3-vinylphenyl)azetidin-3-yl acetate (Ganesh et al., 2007). The reaction scheme is shown in Fig. 2. The absolute configuration (3R,4S) for the two chiral centres of the molecule has been determined.

Related literature top

For the preparation of the title compound, an intermediate in the synthesis of C-4 to C-3' bridged paclitaxel analogues, see: Ganesh et al. (2007).

Experimental top

Lipase PS (Amano) (2.25 g) was added to a solution of racemic 1-(4-methoxyphenyl)-2-oxo-4-(3-vinylphenyl)azetidin-3-yl acetate (2.26 g, 6.7 mmol) in 60 mL of CH3CN and pH 7.0 phosphate buffer (1:9), and the resulting solution was stirred at r.t. for 120 h. The reaction mixture was filtered and extracted with EtOAc (200 mL × 2), the organic layers were combined and solvent was removed under reduced pressure. The residue was purified by flash column chromatography using petroleum ether/EtOAc (4/1) to furnish the title compound (3R,4S)-1-(4-Methoxyphenyl)-2-oxo-4-(3-vinylphenyl)azetidin-3-yl acetate (1 g, 49%) as a white solid. Suitable crystals were obtained by recrystallization from hexane and DCM (m.p. 391.8–392.9 K). 1H NMR (400 MHz, CDCl3): δ 1.71 (s, 3H), 3.88 (s, 3H), 5.28 (d, 1H, J = 10.96 Hz), 5.35 (d, 1H, J = 4.69 Hz), 5.75 (d, 1H, J = 17.61 Hz), 5.95 (d, 1H, J = 4.70 Hz), 6.62–6.76 (m, 1H), 6.81 (d, 2H, J = 9 Hz), 7.18–7.42 (m, 6H); 13C NMR (100 MHz, CDCl3): δ 19.85, 55.45, 61.42, 76.32, 114.45, 114.80, 118.82, 125.86, 126.46, 127.28, 128.72, 130.31, 132.73, 136.20, 137.88, 156.66, 161.32, 169.24; ESIMS m/z 338.0 [M + H]+.

Refinement top

All hydrogen atoms were positioned geometrically and treated as riding with C—H = 0.95–1.00Å and Uiso(H) = 1.2 or 1.5Ueq(C). The title compound was identified as (3R,4S)-1-(4-methoxyphenyl)-2-oxo-4-(3-vinylphenyl)azetidin-3-yl acetate.

Computing details top

Data collection: APEX2 (Bruker, 2010); cell refinement: SAINT (Bruker, 2010); data reduction: SAINT (Bruker, 2010); 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. Molecular configuration and atom numbering scheme for (I).
[Figure 2] Fig. 2. Reaction scheme for the synthesis of (I).
(3R,4S)-1-(4-Methoxyphenyl)-2-oxo-4-(3-vinylphenyl)azetidin-3-yl acetate top
Crystal data top
C20H19NO4F(000) = 712
Mr = 337.36Dx = 1.299 Mg m3
Monoclinic, C2Cu Kα radiation, λ = 1.54178 Å
Hall symbol: C 2yCell parameters from 4349 reflections
a = 20.7448 (4) Åθ = 3.4–66.0°
b = 6.3930 (1) ŵ = 0.74 mm1
c = 15.7434 (3) ÅT = 124 K
β = 124.309 (1)°Block, colourless
V = 1724.64 (5) Å30.20 × 0.18 × 0.11 mm
Z = 4
Data collection top
Bruker APEXII CCD
diffractometer
2374 independent reflections
Radiation source: fine-focus sealed tube2330 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
ϕ and ω scansθmax = 66.3°, θmin = 3.4°
Absorption correction: multi-scan
(SADABS; Bruker, 2010)
h = 2424
Tmin = 0.866, Tmax = 0.923k = 76
6072 measured reflectionsl = 1818
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)] = 0.026H-atom parameters constrained
wR(F2) = 0.069 w = 1/[σ2(Fo2) + (0.0432P)2 + 0.3527P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max = 0.024
2374 reflectionsΔρmax = 0.18 e Å3
228 parametersΔρmin = 0.15 e Å3
1 restraintAbsolute structure: Flack (1983), 730 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.01 (15)
Crystal data top
C20H19NO4V = 1724.64 (5) Å3
Mr = 337.36Z = 4
Monoclinic, C2Cu Kα radiation
a = 20.7448 (4) ŵ = 0.74 mm1
b = 6.3930 (1) ÅT = 124 K
c = 15.7434 (3) Å0.20 × 0.18 × 0.11 mm
β = 124.309 (1)°
Data collection top
Bruker APEXII CCD
diffractometer
2374 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2010)
2330 reflections with I > 2σ(I)
Tmin = 0.866, Tmax = 0.923Rint = 0.024
6072 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.026H-atom parameters constrained
wR(F2) = 0.069Δρmax = 0.18 e Å3
S = 1.06Δρmin = 0.15 e Å3
2374 reflectionsAbsolute structure: Flack (1983), 730 Friedel pairs
228 parametersAbsolute structure parameter: 0.01 (15)
1 restraint
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
N10.01643 (6)0.3030 (2)0.64077 (8)0.0200 (3)
O10.02784 (6)0.65258 (18)0.59931 (8)0.0270 (2)
O20.06828 (5)0.45389 (17)0.74357 (7)0.0222 (2)
O30.15201 (7)0.2201 (2)0.73583 (9)0.0383 (3)
O40.26072 (6)0.13686 (18)0.59965 (8)0.0273 (2)
C10.02761 (7)0.4753 (3)0.62602 (10)0.0211 (3)
C20.07416 (7)0.3539 (2)0.65865 (10)0.0211 (3)
H20.12920.32510.60030.025*
C30.01748 (7)0.1671 (2)0.68246 (10)0.0207 (3)
H30.04510.04260.63800.025*
C40.03811 (7)0.1098 (2)0.79424 (10)0.0211 (3)
C50.02826 (8)0.0778 (3)0.82961 (12)0.0296 (3)
H50.01210.17140.78320.035*
C60.07760 (9)0.1290 (3)0.93339 (12)0.0390 (4)
H60.07040.25720.95760.047*
C70.13680 (9)0.0046 (3)1.00140 (12)0.0360 (4)
H70.16950.03141.07220.043*
C80.14908 (8)0.1925 (3)0.96712 (11)0.0269 (3)
C90.09860 (8)0.2431 (3)0.86306 (11)0.0229 (3)
H90.10570.37110.83870.028*
C100.21420 (9)0.3354 (3)1.03509 (12)0.0332 (4)
H100.21620.46191.00500.040*
C110.26974 (10)0.3070 (4)1.13267 (14)0.0499 (5)
H11A0.27060.18321.16670.060*
H11B0.30900.41021.16920.060*
C120.11309 (8)0.3737 (3)0.77324 (12)0.0272 (3)
C130.10664 (12)0.5031 (4)0.85648 (14)0.0436 (5)
H13A0.15890.52910.84080.065*
H13B0.08160.63670.86130.065*
H13C0.07520.42860.92210.065*
C140.07884 (7)0.2651 (2)0.63024 (9)0.0191 (3)
C150.09304 (7)0.0624 (2)0.61245 (10)0.0224 (3)
H150.06090.04970.60710.027*
C160.15445 (8)0.0252 (2)0.60258 (11)0.0244 (3)
H160.16430.11270.59020.029*
C170.20168 (8)0.1904 (2)0.61088 (10)0.0210 (3)
C180.18780 (8)0.3919 (3)0.62910 (11)0.0239 (3)
H180.22030.50380.63530.029*
C190.12576 (8)0.4292 (3)0.63829 (10)0.0236 (3)
H190.11560.56730.65010.028*
C200.30559 (8)0.3045 (3)0.59786 (13)0.0295 (3)
H20A0.27070.40300.54310.044*
H20B0.34330.24820.58500.044*
H20C0.33350.37710.66420.044*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0204 (5)0.0178 (6)0.0214 (5)0.0002 (5)0.0116 (4)0.0004 (5)
O10.0313 (5)0.0195 (6)0.0351 (5)0.0038 (4)0.0218 (5)0.0041 (5)
O20.0229 (4)0.0220 (6)0.0253 (5)0.0024 (4)0.0159 (4)0.0037 (4)
O30.0451 (6)0.0320 (7)0.0505 (7)0.0147 (6)0.0347 (6)0.0096 (6)
O40.0284 (5)0.0215 (6)0.0406 (5)0.0004 (4)0.0247 (4)0.0021 (5)
C10.0200 (6)0.0215 (8)0.0202 (6)0.0002 (5)0.0105 (5)0.0017 (6)
C20.0210 (6)0.0212 (8)0.0206 (6)0.0000 (6)0.0116 (5)0.0020 (6)
C30.0210 (6)0.0193 (8)0.0238 (6)0.0015 (5)0.0138 (5)0.0010 (6)
C40.0207 (6)0.0206 (8)0.0245 (7)0.0014 (5)0.0143 (5)0.0010 (6)
C50.0266 (7)0.0272 (9)0.0322 (7)0.0042 (6)0.0149 (6)0.0028 (7)
C60.0380 (8)0.0379 (11)0.0357 (8)0.0049 (8)0.0176 (7)0.0149 (9)
C70.0289 (8)0.0483 (12)0.0268 (7)0.0004 (7)0.0133 (6)0.0107 (8)
C80.0217 (7)0.0350 (10)0.0245 (7)0.0005 (6)0.0133 (6)0.0001 (7)
C90.0230 (6)0.0228 (8)0.0260 (7)0.0000 (6)0.0156 (6)0.0013 (6)
C100.0278 (7)0.0408 (11)0.0300 (7)0.0045 (7)0.0157 (6)0.0031 (8)
C110.0360 (9)0.0674 (15)0.0308 (8)0.0154 (9)0.0094 (7)0.0001 (10)
C120.0281 (7)0.0256 (9)0.0331 (7)0.0024 (7)0.0204 (6)0.0017 (7)
C130.0543 (10)0.0499 (13)0.0450 (9)0.0151 (9)0.0392 (9)0.0142 (9)
C140.0195 (6)0.0203 (8)0.0170 (6)0.0018 (5)0.0099 (5)0.0019 (6)
C150.0236 (6)0.0186 (8)0.0251 (7)0.0012 (6)0.0138 (6)0.0021 (6)
C160.0281 (7)0.0167 (8)0.0308 (7)0.0020 (6)0.0180 (6)0.0006 (6)
C170.0201 (6)0.0219 (8)0.0215 (6)0.0016 (5)0.0119 (5)0.0008 (6)
C180.0230 (6)0.0198 (8)0.0295 (7)0.0030 (6)0.0153 (6)0.0013 (7)
C190.0244 (6)0.0178 (8)0.0282 (7)0.0004 (6)0.0147 (6)0.0037 (6)
C200.0267 (7)0.0256 (8)0.0433 (8)0.0009 (6)0.0240 (7)0.0048 (7)
Geometric parameters (Å, º) top
N1—C11.365 (2)C8—C101.475 (2)
N1—C141.4157 (17)C9—H90.9500
N1—C31.4834 (18)C10—C111.313 (2)
O1—C11.208 (2)C10—H100.9500
O2—C121.3547 (18)C11—H11A0.9500
O2—C21.4237 (17)C11—H11B0.9500
O3—C121.194 (2)C12—C131.491 (2)
O4—C171.3760 (16)C13—H13A0.9800
O4—C201.4300 (19)C13—H13B0.9800
C1—C21.535 (2)C13—H13C0.9800
C2—C31.566 (2)C14—C191.387 (2)
C2—H21.0000C14—C151.392 (2)
C3—C41.5077 (19)C15—C161.388 (2)
C3—H31.0000C15—H150.9500
C4—C51.385 (2)C16—C171.396 (2)
C4—C91.393 (2)C16—H160.9500
C5—C61.392 (2)C17—C181.385 (2)
C5—H50.9500C18—C191.394 (2)
C6—C71.379 (3)C18—H180.9500
C6—H60.9500C19—H190.9500
C7—C81.398 (3)C20—H20A0.9800
C7—H70.9500C20—H20B0.9800
C8—C91.397 (2)C20—H20C0.9800
C1—N1—C14133.38 (13)C11—C10—H10116.4
C1—N1—C396.24 (11)C8—C10—H10116.4
C14—N1—C3130.15 (13)C10—C11—H11A120.0
C12—O2—C2116.20 (12)C10—C11—H11B120.0
C17—O4—C20116.91 (12)H11A—C11—H11B120.0
O1—C1—N1133.42 (13)O3—C12—O2123.08 (14)
O1—C1—C2135.29 (13)O3—C12—C13126.19 (15)
N1—C1—C291.28 (12)O2—C12—C13110.73 (14)
O2—C2—C1110.50 (12)C12—C13—H13A109.5
O2—C2—C3117.53 (11)C12—C13—H13B109.5
C1—C2—C386.35 (10)H13A—C13—H13B109.5
O2—C2—H2113.2C12—C13—H13C109.5
C1—C2—H2113.2H13A—C13—H13C109.5
C3—C2—H2113.2H13B—C13—H13C109.5
N1—C3—C4114.66 (11)C19—C14—C15120.34 (12)
N1—C3—C285.81 (11)C19—C14—N1120.06 (14)
C4—C3—C2116.23 (12)C15—C14—N1119.60 (13)
N1—C3—H3112.5C16—C15—C14119.60 (14)
C4—C3—H3112.5C16—C15—H15120.2
C2—C3—H3112.5C14—C15—H15120.2
C5—C4—C9119.27 (13)C15—C16—C17119.98 (14)
C5—C4—C3119.38 (13)C15—C16—H16120.0
C9—C4—C3121.34 (14)C17—C16—H16120.0
C4—C5—C6119.86 (15)O4—C17—C18124.20 (13)
C4—C5—H5120.1O4—C17—C16115.37 (13)
C6—C5—H5120.1C18—C17—C16120.42 (13)
C7—C6—C5120.61 (16)C17—C18—C19119.50 (14)
C7—C6—H6119.7C17—C18—H18120.2
C5—C6—H6119.7C19—C18—H18120.2
C6—C7—C8120.59 (14)C14—C19—C18120.15 (15)
C6—C7—H7119.7C14—C19—H19119.9
C8—C7—H7119.7C18—C19—H19119.9
C9—C8—C7118.18 (14)O4—C20—H20A109.5
C9—C8—C10118.85 (15)O4—C20—H20B109.5
C7—C8—C10122.94 (14)H20A—C20—H20B109.5
C4—C9—C8121.45 (15)O4—C20—H20C109.5
C4—C9—H9119.3H20A—C20—H20C109.5
C8—C9—H9119.3H20B—C20—H20C109.5
C11—C10—C8127.16 (19)
C14—N1—C1—O10.2 (3)C6—C7—C8—C91.7 (2)
C3—N1—C1—O1174.55 (16)C6—C7—C8—C10176.31 (17)
C14—N1—C1—C2179.17 (13)C5—C4—C9—C80.6 (2)
C3—N1—C1—C24.44 (11)C3—C4—C9—C8178.51 (13)
C12—O2—C2—C1173.69 (12)C7—C8—C9—C40.9 (2)
C12—O2—C2—C389.52 (15)C10—C8—C9—C4177.16 (14)
O1—C1—C2—O256.7 (2)C9—C8—C10—C11175.47 (18)
N1—C1—C2—O2122.26 (11)C7—C8—C10—C112.5 (3)
O1—C1—C2—C3174.77 (17)C2—O2—C12—O34.6 (2)
N1—C1—C2—C34.19 (10)C2—O2—C12—C13175.14 (14)
C1—N1—C3—C4112.63 (13)C1—N1—C14—C1924.9 (2)
C14—N1—C3—C462.36 (19)C3—N1—C14—C19148.25 (14)
C1—N1—C3—C24.37 (11)C1—N1—C14—C15155.51 (14)
C14—N1—C3—C2179.35 (13)C3—N1—C14—C1531.4 (2)
O2—C2—C3—N1115.12 (12)C19—C14—C15—C160.1 (2)
C1—C2—C3—N13.86 (10)N1—C14—C15—C16179.71 (12)
O2—C2—C3—C40.37 (19)C14—C15—C16—C170.2 (2)
C1—C2—C3—C4111.62 (13)C20—O4—C17—C185.7 (2)
N1—C3—C4—C5151.25 (14)C20—O4—C17—C16174.20 (12)
C2—C3—C4—C5110.90 (16)C15—C16—C17—O4179.83 (12)
N1—C3—C4—C929.63 (19)C15—C16—C17—C180.1 (2)
C2—C3—C4—C968.22 (17)O4—C17—C18—C19179.39 (12)
C9—C4—C5—C61.4 (2)C16—C17—C18—C190.5 (2)
C3—C4—C5—C6177.79 (14)C15—C14—C19—C180.3 (2)
C4—C5—C6—C70.6 (3)N1—C14—C19—C18179.28 (12)
C5—C6—C7—C80.9 (3)C17—C18—C19—C140.6 (2)

Experimental details

Crystal data
Chemical formulaC20H19NO4
Mr337.36
Crystal system, space groupMonoclinic, C2
Temperature (K)124
a, b, c (Å)20.7448 (4), 6.3930 (1), 15.7434 (3)
β (°) 124.309 (1)
V3)1724.64 (5)
Z4
Radiation typeCu Kα
µ (mm1)0.74
Crystal size (mm)0.20 × 0.18 × 0.11
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2010)
Tmin, Tmax0.866, 0.923
No. of measured, independent and
observed [I > 2σ(I)] reflections
6072, 2374, 2330
Rint0.024
(sin θ/λ)max1)0.594
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.026, 0.069, 1.06
No. of reflections2374
No. of parameters228
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.18, 0.15
Absolute structureFlack (1983), 730 Friedel pairs
Absolute structure parameter0.01 (15)

Computer programs: APEX2 (Bruker, 2010), SAINT (Bruker, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

The work was supported financially by the National Natural Science Foundation of China (No. 81172920), the Shanghai Municipal Committee of Science and Technology (No. 10431903100) and the National Basic Research Program of China (973 Program, No. 2010CB912603). We would like to thank Dr Jie Sun for the single-crystal X-ray determination.

References

First citationBruker (2010). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.
First citationFlack, H. D. (1983). Acta Cryst. A39, 876–881.  CrossRef CAS Web of Science IUCr Journals
First citationGanesh, T., Yang, C., Norris, A., Glass, T., Bane, S., Ravindra, R., Banerjee, A., Metaferia, B., Thomas, S. L. & Giannakakou, P. (2007). J. Med. Chem. 50, 713–725.  Web of Science CrossRef PubMed CAS
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals

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