organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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Crystal structure of (2-methyl-4-phenyl-4H-benzo[4,5]thia­zolo[3,2-a]pyrimidin-3-yl)(phen­yl)methanone

aCentre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India, bInstitution of Excellence, University of Mysore, Manasagangotri, Mysore 570 006, India, and cDepartment of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006, India
*Correspondence e-mail: gunaunom@gmail.com

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 27 March 2015; accepted 30 March 2015; online 2 April 2015)

In the title compound, C24H18N2OS, the pyrimidine ring has a flat envelope conformation with the methine C atom as the flap. The attached phenyl and benzoyl rings are inclined to the mean plane of the pyrimidine ring by 84.87 (8) and 75.33 (9)°, respectively. The benzo­thia­zolo group is planar (r.m.s. deviation = 0.009 Å) and inclined to the mean plane of the pyrimidine ring by 3.27 (6)°. In the crystal, mol­ecules are linked by pairs of C—H⋯N hydrogen bonds, forming inversion dimers.

1. Related literature

For general background to the biological activities of pyrimidine derivatives, see: Kumar et al. (2002[Kumar, A., Sinha, S. & Chauhan, P. M. (2002). Bioorg. Med. Chem. Lett. 12, 667-669.]); Baraldi et al. (2002[Baraldi, P. G., Pavani, M. G., Nuñez, M. del C., Brigidi, P., Vitali, B., Gambari, R. & Romagnoli, R. (2002). Bioorg. Med. Chem. 10, 449-456.]); Nasr & Gineinah (2002[Nasr, M. N. & Gineinah, M. M. (2002). Arch. Pharm. Pharm. Med. Chem. 335, 289-295.]). For literature on the synthesis of fused benzo­thia­zolo derivatives, see: Nagarapu et al. (2013a[Nagarapu, L., Gaikwad, H. K., Palem, J. D., Venkatesh, R., Bantu, R. & Sridhar, B. (2013a). Synth. Commun. 43, 93-104.],b[Nagarapu, L., Vanaparthi, S., Bantu, R. & Kumar, C. G. (2013b). Eur. J. Med. Chem. 69, 817-822.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C24H18N2OS

  • Mr = 382.46

  • Monoclinic, P 21 /c

  • a = 12.1894 (6) Å

  • b = 18.6119 (8) Å

  • c = 8.9370 (4) Å

  • β = 110.360 (1)°

  • V = 1900.85 (15) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 1.64 mm−1

  • T = 296 K

  • 0.25 × 0.20 × 0.18 mm

2.2. Data collection

  • Bruker SMART APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.709, Tmax = 0.745

  • 11594 measured reflections

  • 3090 independent reflections

  • 3047 reflections with I > 2σ(I)

  • Rint = 0.036

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.109

  • S = 1.08

  • 3090 reflections

  • 254 parameters

  • H-atom parameters constrained

  • Δρmax = 0.28 e Å−3

  • Δρmin = −0.33 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C27—H27⋯N1i 0.93 2.56 3.472 (2) 166
Symmetry code: (i) -x+2, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). 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: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Synthesis and crystallization top

A mixture of benzaldehyde was treated with 1-phenyl butane 1-3-dione and 2-amino­benzo­thia­zole in the presence of ammonium acetate in ethanol. The mixture was gently warmed in a water bath at 353 K until the colour changed to yellow. It was kept aside overnight at room temperature. On completion of reaction (monitored by TLC) the solid obtained was separated and purified by column chromatography using hexane and ethyl acetate as eluent. The solid obtained was recrystallized using a 1:1 mixture of ethanol and THF giving yellow block-like crystals.

Structural commentary top

Many pyrimidine derivatives show strong activity against bacteria, tumor and some viruses (Kumar et al., 2012; Baraldi et al., 2002; Nasr & Gineinah, 2002). Owing to the above said important properties of pyrimidine derivatives,the crystal structure determination of the title compound is carried out.

The molecular structure of the title compound is shown in Fig. 1. The pyrimidine ring [N1/C2/N19/C11—C13] has a envelope conformation with the maximum deviation of 0.1342 (17) Å shown by the flap atom C11. The attached phenyl ring [C15—C20] is twisted at an angle of 84.87 (8) ° with respect to pyrimidine ring mean plane. The thia­zolo group [S3/C2/N10/C4/C9] is also planar and fused with a benzene ring [C4—C9]. The phenyl­methanone ring [C23—C28] is almost perpendicular to the pyrimidine ring mean plane, with a dihedral angle between of 75.33 (9) Å.

In the crystal, molecules are linked via pairs of C—H···N hydrogen bonds forming inversion dimers (Table 1 and Fig. 2).

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 2. H atoms were positioned geometrically (C—H = 0.93-0.98 Å) and allowed to ride on their parent atoms, with Uiso(H) = 1.5Ueq(C) for methyl H atoms and 1.2Ueq(C) for other H atoms.

Related literature top

For general background to the biological activities of pyrimidine derivatives, see: Kumar et al. (2002); Baraldi et al. (2002); Nasr & Gineinah (2002). For literature on the synthesis of fused benzothiazolo derivatives, see: Nagarapu et al. (2013a,b).

Structure description top

Many pyrimidine derivatives show strong activity against bacteria, tumor and some viruses (Kumar et al., 2012; Baraldi et al., 2002; Nasr & Gineinah, 2002). Owing to the above said important properties of pyrimidine derivatives,the crystal structure determination of the title compound is carried out.

The molecular structure of the title compound is shown in Fig. 1. The pyrimidine ring [N1/C2/N19/C11—C13] has a envelope conformation with the maximum deviation of 0.1342 (17) Å shown by the flap atom C11. The attached phenyl ring [C15—C20] is twisted at an angle of 84.87 (8) ° with respect to pyrimidine ring mean plane. The thia­zolo group [S3/C2/N10/C4/C9] is also planar and fused with a benzene ring [C4—C9]. The phenyl­methanone ring [C23—C28] is almost perpendicular to the pyrimidine ring mean plane, with a dihedral angle between of 75.33 (9) Å.

In the crystal, molecules are linked via pairs of C—H···N hydrogen bonds forming inversion dimers (Table 1 and Fig. 2).

For general background to the biological activities of pyrimidine derivatives, see: Kumar et al. (2002); Baraldi et al. (2002); Nasr & Gineinah (2002). For literature on the synthesis of fused benzothiazolo derivatives, see: Nagarapu et al. (2013a,b).

Synthesis and crystallization top

A mixture of benzaldehyde was treated with 1-phenyl butane 1-3-dione and 2-amino­benzo­thia­zole in the presence of ammonium acetate in ethanol. The mixture was gently warmed in a water bath at 353 K until the colour changed to yellow. It was kept aside overnight at room temperature. On completion of reaction (monitored by TLC) the solid obtained was separated and purified by column chromatography using hexane and ethyl acetate as eluent. The solid obtained was recrystallized using a 1:1 mixture of ethanol and THF giving yellow block-like crystals.

Refinement details top

Crystal data, data collection and structure refinement details are summarized in Table 2. H atoms were positioned geometrically (C—H = 0.93-0.98 Å) and allowed to ride on their parent atoms, with Uiso(H) = 1.5Ueq(C) for methyl H atoms and 1.2Ueq(C) for other H atoms.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with atom labelling. The displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. The crystal packing of the title compound viewed along the a axis. The hydrogen bonds are shown as dashed lines (see Table 1 for details).
(2-Methyl-4-phenyl-4H-benzo[4,5]thiazolo[3,2-a]pyrimidin-3-yl)(phenyl)methanone top
Crystal data top
C24H18N2OSF(000) = 800
Mr = 382.46Dx = 1.336 Mg m3
Monoclinic, P21/cCu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2ybcCell parameters from 3047 reflections
a = 12.1894 (6) Åθ = 4.8–64.4°
b = 18.6119 (8) ŵ = 1.64 mm1
c = 8.9370 (4) ÅT = 296 K
β = 110.360 (1)°Block, yellow
V = 1900.85 (15) Å30.25 × 0.20 × 0.18 mm
Z = 4
Data collection top
Bruker SMART APEXII CCD
diffractometer
3090 independent reflections
Radiation source: fine-focus sealed tube3047 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.036
ω and φ scansθmax = 64.4°, θmin = 4.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 1412
Tmin = 0.709, Tmax = 0.745k = 2119
11594 measured reflectionsl = 1010
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)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.109H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.0592P)2 + 1.0365P]
where P = (Fo2 + 2Fc2)/3
3090 reflections(Δ/σ)max = 0.001
254 parametersΔρmax = 0.28 e Å3
0 restraintsΔρmin = 0.33 e Å3
Crystal data top
C24H18N2OSV = 1900.85 (15) Å3
Mr = 382.46Z = 4
Monoclinic, P21/cCu Kα radiation
a = 12.1894 (6) ŵ = 1.64 mm1
b = 18.6119 (8) ÅT = 296 K
c = 8.9370 (4) Å0.25 × 0.20 × 0.18 mm
β = 110.360 (1)°
Data collection top
Bruker SMART APEXII CCD
diffractometer
3090 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
3047 reflections with I > 2σ(I)
Tmin = 0.709, Tmax = 0.745Rint = 0.036
11594 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.109H-atom parameters constrained
S = 1.08Δρmax = 0.28 e Å3
3090 reflectionsΔρmin = 0.33 e Å3
254 parameters
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
S30.78290 (4)0.78385 (2)0.29579 (5)0.02105 (16)
O220.63518 (10)0.46696 (6)0.01765 (14)0.0218 (3)
N100.67761 (11)0.66193 (7)0.23307 (16)0.0153 (3)
N10.86815 (12)0.66330 (7)0.21581 (17)0.0185 (3)
C230.81232 (14)0.42002 (9)0.1606 (2)0.0176 (4)
C150.66359 (13)0.54627 (9)0.36319 (19)0.0158 (3)
C210.72853 (14)0.47969 (9)0.08872 (18)0.0159 (3)
C90.59793 (14)0.70747 (9)0.26642 (19)0.0168 (4)
C130.85112 (14)0.59148 (9)0.16452 (19)0.0166 (3)
C200.59791 (15)0.48448 (9)0.3530 (2)0.0199 (4)
H200.54470.47010.25490.024*
C80.48789 (15)0.68936 (9)0.2670 (2)0.0212 (4)
H80.45880.64300.24270.025*
C120.75429 (14)0.55374 (9)0.15422 (18)0.0156 (3)
C110.65887 (13)0.58425 (8)0.20997 (19)0.0151 (3)
H110.58230.57560.12750.018*
C240.81031 (16)0.35791 (9)0.0720 (2)0.0239 (4)
H240.76080.35520.03390.029*
C20.78084 (14)0.69288 (9)0.24274 (19)0.0161 (3)
C50.57494 (15)0.83013 (9)0.3392 (2)0.0220 (4)
H50.60340.87670.36220.026*
C70.42230 (16)0.74266 (10)0.3051 (2)0.0246 (4)
H70.34830.73160.30680.030*
C60.46508 (16)0.81215 (10)0.3406 (2)0.0242 (4)
H60.41950.84690.36560.029*
C280.88470 (15)0.42280 (10)0.3196 (2)0.0229 (4)
H280.88690.46410.37920.027*
C180.68805 (17)0.46582 (10)0.6348 (2)0.0276 (4)
H180.69720.43850.72550.033*
C250.88206 (18)0.30017 (10)0.1416 (3)0.0308 (4)
H250.88240.25950.08140.037*
C140.95013 (15)0.56424 (10)0.1177 (2)0.0229 (4)
H14A0.93230.51670.07440.034*
H14B1.02040.56300.20990.034*
H14C0.96120.59550.03880.034*
C40.64142 (15)0.77729 (9)0.30278 (19)0.0183 (4)
C160.74035 (15)0.56846 (9)0.5113 (2)0.0219 (4)
H160.78400.61020.51910.026*
C170.75201 (16)0.52884 (10)0.6466 (2)0.0257 (4)
H170.80260.54420.74550.031*
C270.95393 (16)0.36400 (11)0.3900 (2)0.0297 (4)
H271.00080.36560.49720.036*
C260.95303 (17)0.30319 (11)0.3006 (3)0.0307 (4)
H261.00020.26420.34750.037*
C190.61111 (17)0.44390 (10)0.4884 (2)0.0269 (4)
H190.56810.40190.48050.032*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S30.0211 (3)0.0137 (3)0.0288 (3)0.00246 (15)0.00924 (19)0.00270 (15)
O220.0202 (6)0.0214 (6)0.0200 (6)0.0014 (5)0.0022 (5)0.0039 (5)
N100.0169 (7)0.0114 (7)0.0184 (7)0.0003 (5)0.0070 (5)0.0001 (5)
N10.0174 (7)0.0168 (7)0.0215 (7)0.0005 (5)0.0071 (6)0.0008 (6)
C230.0164 (8)0.0159 (8)0.0229 (8)0.0006 (6)0.0099 (7)0.0014 (7)
C150.0152 (8)0.0152 (8)0.0188 (8)0.0035 (6)0.0080 (6)0.0007 (6)
C210.0175 (8)0.0189 (9)0.0135 (7)0.0002 (6)0.0082 (6)0.0001 (6)
C90.0189 (8)0.0161 (8)0.0147 (8)0.0033 (6)0.0049 (6)0.0001 (6)
C130.0166 (8)0.0172 (8)0.0150 (8)0.0029 (6)0.0041 (6)0.0022 (6)
C200.0222 (8)0.0180 (8)0.0189 (8)0.0025 (7)0.0064 (7)0.0014 (7)
C80.0217 (9)0.0168 (9)0.0265 (9)0.0008 (7)0.0101 (7)0.0017 (7)
C120.0162 (8)0.0161 (8)0.0145 (8)0.0030 (6)0.0053 (6)0.0014 (6)
C110.0150 (8)0.0128 (8)0.0168 (8)0.0002 (6)0.0046 (6)0.0018 (6)
C240.0280 (9)0.0201 (9)0.0260 (9)0.0026 (7)0.0123 (7)0.0012 (7)
C20.0174 (8)0.0151 (8)0.0147 (8)0.0005 (6)0.0041 (6)0.0012 (6)
C50.0278 (9)0.0147 (8)0.0223 (9)0.0020 (7)0.0072 (7)0.0031 (7)
C70.0220 (9)0.0246 (10)0.0300 (9)0.0031 (7)0.0127 (7)0.0015 (7)
C60.0276 (9)0.0203 (9)0.0263 (9)0.0071 (7)0.0114 (7)0.0018 (7)
C280.0216 (9)0.0210 (9)0.0244 (9)0.0016 (7)0.0059 (7)0.0008 (7)
C180.0384 (11)0.0250 (10)0.0222 (9)0.0030 (8)0.0140 (8)0.0063 (7)
C250.0378 (11)0.0180 (9)0.0442 (12)0.0065 (8)0.0238 (9)0.0002 (8)
C140.0206 (9)0.0223 (9)0.0294 (9)0.0014 (7)0.0131 (7)0.0012 (7)
C40.0204 (9)0.0168 (8)0.0164 (8)0.0009 (6)0.0048 (7)0.0003 (6)
C160.0238 (9)0.0201 (9)0.0212 (9)0.0032 (7)0.0070 (7)0.0025 (7)
C170.0294 (9)0.0280 (10)0.0172 (8)0.0009 (8)0.0050 (7)0.0016 (7)
C270.0247 (9)0.0303 (10)0.0311 (10)0.0073 (8)0.0060 (8)0.0094 (8)
C260.0267 (10)0.0237 (10)0.0452 (12)0.0110 (8)0.0171 (9)0.0126 (8)
C190.0353 (10)0.0210 (9)0.0271 (10)0.0060 (8)0.0143 (8)0.0021 (7)
Geometric parameters (Å, º) top
S3—C41.7515 (18)C24—C251.389 (3)
S3—C21.7560 (16)C24—H240.9300
O22—C211.225 (2)C5—C41.383 (2)
N10—C21.359 (2)C5—C61.385 (3)
N10—C91.397 (2)C5—H50.9300
N10—C111.467 (2)C7—C61.389 (3)
N1—C21.293 (2)C7—H70.9300
N1—C131.405 (2)C6—H60.9300
C23—C281.389 (2)C28—C271.391 (3)
C23—C241.396 (2)C28—H280.9300
C23—C211.494 (2)C18—C191.380 (3)
C15—C201.386 (2)C18—C171.392 (3)
C15—C161.391 (2)C18—H180.9300
C15—C111.524 (2)C25—C261.384 (3)
C21—C121.488 (2)C25—H250.9300
C9—C81.385 (2)C14—H14A0.9600
C9—C41.398 (2)C14—H14B0.9600
C13—C121.349 (2)C14—H14C0.9600
C13—C141.497 (2)C16—C171.381 (3)
C20—C191.388 (3)C16—H160.9300
C20—H200.9300C17—H170.9300
C8—C71.389 (3)C27—C261.383 (3)
C8—H80.9300C27—H270.9300
C12—C111.525 (2)C26—H260.9300
C11—H110.9800C19—H190.9300
C4—S3—C291.18 (8)C4—C5—H5120.7
C2—N10—C9115.23 (13)C6—C5—H5120.7
C2—N10—C11121.47 (13)C8—C7—C6121.25 (17)
C9—N10—C11122.83 (13)C8—C7—H7119.4
C2—N1—C13115.35 (14)C6—C7—H7119.4
C28—C23—C24119.38 (16)C5—C6—C7120.67 (16)
C28—C23—C21120.53 (15)C5—C6—H6119.7
C24—C23—C21119.81 (15)C7—C6—H6119.7
C20—C15—C16119.38 (16)C23—C28—C27120.18 (17)
C20—C15—C11119.04 (14)C23—C28—H28119.9
C16—C15—C11121.31 (15)C27—C28—H28119.9
O22—C21—C12119.75 (14)C19—C18—C17119.92 (17)
O22—C21—C23120.07 (15)C19—C18—H18120.0
C12—C21—C23120.03 (13)C17—C18—H18120.0
C8—C9—N10126.81 (15)C26—C25—C24119.97 (18)
C8—C9—C4120.99 (15)C26—C25—H25120.0
N10—C9—C4112.20 (14)C24—C25—H25120.0
C12—C13—N1122.97 (15)C13—C14—H14A109.5
C12—C13—C14125.18 (15)C13—C14—H14B109.5
N1—C13—C14111.81 (14)H14A—C14—H14B109.5
C15—C20—C19120.36 (16)C13—C14—H14C109.5
C15—C20—H20119.8H14A—C14—H14C109.5
C19—C20—H20119.8H14B—C14—H14C109.5
C9—C8—C7117.90 (16)C5—C4—C9120.64 (16)
C9—C8—H8121.1C5—C4—S3128.57 (14)
C7—C8—H8121.1C9—C4—S3110.79 (12)
C13—C12—C21124.69 (15)C17—C16—C15120.32 (16)
C13—C12—C11122.17 (15)C17—C16—H16119.8
C21—C12—C11113.13 (13)C15—C16—H16119.8
N10—C11—C15112.04 (13)C16—C17—C18119.97 (16)
N10—C11—C12108.29 (13)C16—C17—H17120.0
C15—C11—C12109.03 (12)C18—C17—H17120.0
N10—C11—H11109.1C26—C27—C28120.05 (18)
C15—C11—H11109.1C26—C27—H27120.0
C12—C11—H11109.1C28—C27—H27120.0
C25—C24—C23120.18 (17)C27—C26—C25120.19 (17)
C25—C24—H24119.9C27—C26—H26119.9
C23—C24—H24119.9C25—C26—H26119.9
N1—C2—N10127.70 (15)C18—C19—C20120.02 (17)
N1—C2—S3121.70 (13)C18—C19—H19120.0
N10—C2—S3110.59 (12)C20—C19—H19120.0
C4—C5—C6118.55 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C27—H27···N1i0.932.563.472 (2)166
Symmetry code: (i) x+2, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C27—H27···N1i0.932.5633.472 (2)166
Symmetry code: (i) x+2, y+1, z+1.
 

Acknowledgements

The authors are thankful to Institution of Excellence, University of Mysore, for providing the single-crystal X-ray diffraction facility.

References

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