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ISSN: 2056-9890

(Z)-3-(2,4-Di­chloro­benz­yl)-1,5-benzo­thia­zepin-4(5H)-one

aDepartment of Physics, Thanthai Periyar Government Institute of Technology, Vellore 632 002, India, bDepartment of Physics, Bharathidasan Engineering College, Nattrampalli, Vellore 635 854, India, and cDepartment of Organic Chemistry, University of Madras, Maraimalai Campus, Chennai 600 025, India
*Correspondence e-mail: smurugavel27@gmail.com

(Received 16 March 2013; accepted 18 March 2013; online 23 March 2013)

In the title compound, C16H11Cl2NOS, the seven-membered thia­zepine ring adopts a distorted twist-boat conformation. The dihedral angle between the mean plane of the benzothia­zepine ring system and the benzene ring is 78.6 (1)°. The mol­ecular conformation is stabilized by a weak intra­molecular C—H⋯Cl hydrogen bond, which generates an S(5) ring motif. In the crystal, pairs of N—H⋯O hydrogen bonds link inversion-related mol­ecules into dimers, generating R22(8) ring motifs. The crystal packing also features alternating ππ inter­actions between benzothia­zepine benzene rings [inter-centroid distance = 3.740 (3) Å] and dichloro­benzene rings [inter-centroid distance = 3.882 (3) Å] to consolidate a three-dimensional architecture.

Related literature

For background to the biology and related structures of thia­zepin derivatives, see: Bakthadoss et al. (2013[Bakthadoss, M., Selvakumar, R., Manikandan, N. & Murugavel, S. (2013). Acta Cryst. E69, o562-o563.]). For ring-puckering parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C16H11Cl2NOS

  • Mr = 336.22

  • Triclinic, [P \overline 1]

  • a = 7.879 (5) Å

  • b = 9.667 (5) Å

  • c = 9.979 (5) Å

  • α = 89.052 (5)°

  • β = 78.161 (4)°

  • γ = 83.647 (5)°

  • V = 739.3 (7) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.58 mm−1

  • T = 293 K

  • 0.24 × 0.21 × 0.15 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.871, Tmax = 0.917

  • 18415 measured reflections

  • 5225 independent reflections

  • 4013 reflections with I > 2σ(I)

  • Rint = 0.026

Refinement
  • R[F2 > 2σ(F2)] = 0.042

  • wR(F2) = 0.123

  • S = 1.04

  • 5225 reflections

  • 190 parameters

  • H-atom parameters constrained

  • Δρmax = 0.55 e Å−3

  • Δρmin = −0.44 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C10—H10B⋯Cl1 0.97 2.64 3.103 (3) 109
N1—H1A⋯O1i 0.86 2.10 2.873 (2) 149
Symmetry code: (i) -x+2, -y+1, -z+2.

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2, SAINT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2 and SAINT (Bruker, 2004[Bruker (2004). APEX2, SAINT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT and XPREP (Bruker, 2004[Bruker (2004). APEX2, SAINT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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


Comment top

The background to the biology and related structures of thiazepin derivatives, has been described recently (Bakthadoss et al., 2013). In view of this biological importance, the crystal structure of the title compound has been carried out and the results are presented here.

Fig. 1. shows a displacement ellipsoid plot of (I), with the atom numbering scheme. The seven membered thiazepine ring (N1/S1/C1/C2/C7/C8/C9) adopts distorted twist-boat conformation as indicated by puckering parameters (Cremer & Pople, 1975): QT = 0.8962 (12) Å, ϕ2 = 353.2 (1)° and ϕ3 = 358.9 (3)°. The atom O1 deviates by 0.667 (1) Å from the least-squares plane of the thiazepin ring. The dihedral angle between the benzothiazepin ring system and the benzene ring is 78.6 (1)°. The atoms Cl1 and Cl2 deviate by 0.075 (1) and -0.006 (1) Å, respectively, from the plane of the attached benzene ring (C11–C16). The sum of angles at N1 atom of the thiazepin ring (360.0°) is in accordance with sp2 hybridization. The geometric parameters of the title molecule agree well with those reported for similar structures (Bakthadoss et al., 2013).

The molecular conformation is stabilized by a weak intramolecular C10—H10B···Cl1 hydrogen bond, which generates an S(5) ring motif (Bernstein et al., 1995). In the crystal packing, molecules are linked by N1—H1A···O1 hydrogen bonds into cyclic centrosymmetric R22(8) dimers (Fig. 2 and Table 1). The crystal packing is further stabilized by alternating ππ interactions with Cg1···Cg1ii = 3.740 (3) Å (symmetry code: (ii) = 2-x, -y, 2-z) and Cg2···Cg2iii = 3.882 (3) Å (symmetry code: (iii) = 1-x, 1-y, 1-z) forming supramolecular stacks along the a axis (Fig. 3; Cg1 and Cg2 are the centroids of the C2–C7 and C11–C16 benzene rings, respectively).

Related literature top

For background to the biology and related structures of thiazepin derivatives, see: Bakthadoss et al. (2013). For ring-puckering parameters, see: Cremer & Pople (1975). For hydrogen-bond motifs, see: Bernstein et al. (1995).

Experimental top

A mixture of (Z)-methyl 2-(bromomethyl)-3-(2,4-dichlorophenyl)acrylate 2 mmol) and o-aminothiophenol (2 mmol) in the presence of potassium tert-butoxide (4.8 mmol) in dry THF (10 ml) was stirred at room temperature for 1 h. After the completion of the reaction as indicated by TLC, the reaction mixture was concentrated and the resulting crude mass was diluted with water (20 ml) and extracted with ethyl acetate (3 x 20 ml). The organic layer was washed with brine (2 x 20 ml) and dried over anhydrous sodium sulfate. The organic layer was concentrated, which successfully provide the crude final product ((Z)-3-(2,4dichlorobenzyl)benzo[b][1,4]thiazepin-4(5H)-one). The final product was purified by column chromatography on silica gel to afford the title compound in good yield (42%). Single crystals suitable for X-ray diffraction were obtained by slow evaporation of its ethylacetate solution at room temperature.

Refinement top

All the H atoms were positioned geometrically and constrained to ride on their parent atom with C—H = 0.93–0.97 Å and N—H = 0.86 Å, and with Uiso(H)=1.5Ueq for methyl H atoms and 1.2Ueq(C) for other H atoms.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); 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. Molecular structure of the title compound showing displacement ellipsoids at the 30% probability level. H atoms are presented as a small spheres of arbitrary radii.
[Figure 2] Fig. 2. Part of the crystal structure of the title compound showing N—H···O intermolecular hydrogen bonds (dotted lines) generating R22(8) centrosymmetric dimers [Symmetry code: (i) 2-x, 1-y, 2-z].
[Figure 3] Fig. 3. A view of alternating ππ interactions forming supramolecular stacks along the a axis in the crystal structure of the title compound. Cg1 and Cg2 are the centroids of the (C2–C7) and (C11–C16) benzene rings, respectively [Symmetry code: (ii) 2-x, -y, 2-z; (iii) 1-x, 1-y, 1-z; (iv) -1+x, 1+y, -1+z; (v) -x, 2-y, -z].
(Z)-3-(2,4-Dichlorobenzyl)-1,5-benzothiazepin-4(5H)-one top
Crystal data top
C16H11Cl2NOSZ = 2
Mr = 336.22F(000) = 344
Triclinic, P1Dx = 1.510 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.879 (5) ÅCell parameters from 5914 reflections
b = 9.667 (5) Åθ = 2.1–33.7°
c = 9.979 (5) ŵ = 0.58 mm1
α = 89.052 (5)°T = 293 K
β = 78.161 (4)°Block, colourless
γ = 83.647 (5)°0.24 × 0.21 × 0.15 mm
V = 739.3 (7) Å3
Data collection top
Bruker APEXII CCD
diffractometer
5225 independent reflections
Radiation source: fine-focus sealed tube4013 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.026
Detector resolution: 10.0 pixels mm-1θmax = 33.7°, θmin = 2.1°
ω scansh = 1211
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
k = 1414
Tmin = 0.871, Tmax = 0.917l = 1415
18415 measured reflections
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)] = 0.042Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.123H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0583P)2 + 0.2157P]
where P = (Fo2 + 2Fc2)/3
5225 reflections(Δ/σ)max = 0.001
190 parametersΔρmax = 0.55 e Å3
0 restraintsΔρmin = 0.44 e Å3
Crystal data top
C16H11Cl2NOSγ = 83.647 (5)°
Mr = 336.22V = 739.3 (7) Å3
Triclinic, P1Z = 2
a = 7.879 (5) ÅMo Kα radiation
b = 9.667 (5) ŵ = 0.58 mm1
c = 9.979 (5) ÅT = 293 K
α = 89.052 (5)°0.24 × 0.21 × 0.15 mm
β = 78.161 (4)°
Data collection top
Bruker APEXII CCD
diffractometer
5225 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
4013 reflections with I > 2σ(I)
Tmin = 0.871, Tmax = 0.917Rint = 0.026
18415 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0420 restraints
wR(F2) = 0.123H-atom parameters constrained
S = 1.04Δρmax = 0.55 e Å3
5225 reflectionsΔρmin = 0.44 e Å3
190 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
C10.53450 (18)0.28937 (15)0.94205 (15)0.0366 (3)
H10.45460.26730.89110.044*
C20.6952 (2)0.14986 (15)1.12880 (14)0.0371 (3)
C30.6971 (3)0.01550 (17)1.18247 (17)0.0510 (4)
H30.59510.02771.19960.061*
C40.8473 (3)0.05324 (19)1.21016 (19)0.0622 (5)
H40.84660.14241.24670.075*
C50.9993 (3)0.0092 (2)1.18406 (19)0.0600 (5)
H51.10100.03741.20380.072*
C61.0008 (2)0.14161 (19)1.12835 (17)0.0469 (3)
H61.10370.18361.11060.056*
C70.84959 (19)0.21138 (14)1.09904 (14)0.0352 (3)
C80.79730 (18)0.41136 (14)0.94238 (15)0.0349 (3)
C90.66727 (17)0.35381 (13)0.87569 (14)0.0321 (2)
C100.6884 (2)0.39317 (17)0.72620 (15)0.0423 (3)
H10A0.69680.49240.71860.051*
H10B0.79780.34600.67670.051*
C110.5449 (2)0.35964 (15)0.65712 (14)0.0371 (3)
C120.55727 (19)0.24270 (15)0.57559 (15)0.0359 (3)
C130.42879 (19)0.21821 (15)0.50589 (15)0.0388 (3)
H130.44190.14020.44990.047*
C140.28122 (19)0.31163 (16)0.52118 (14)0.0390 (3)
C150.2600 (2)0.42737 (18)0.60401 (18)0.0477 (4)
H150.15830.48860.61580.057*
C160.3933 (2)0.45071 (17)0.66928 (17)0.0469 (4)
H160.38080.53020.72320.056*
N10.85975 (16)0.34776 (12)1.04633 (13)0.0375 (3)
H1A0.91550.39901.08790.045*
O10.84965 (17)0.52292 (12)0.89978 (14)0.0545 (3)
Cl10.73749 (6)0.11906 (5)0.55837 (6)0.06427 (15)
Cl20.11969 (6)0.27905 (6)0.43563 (5)0.05837 (14)
S10.49323 (5)0.24136 (4)1.11466 (4)0.04389 (11)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0354 (7)0.0435 (7)0.0355 (7)0.0151 (5)0.0122 (5)0.0003 (5)
C20.0443 (7)0.0377 (6)0.0304 (6)0.0118 (5)0.0059 (5)0.0013 (5)
C30.0692 (11)0.0425 (8)0.0405 (8)0.0178 (8)0.0032 (7)0.0067 (6)
C40.0933 (16)0.0444 (9)0.0444 (9)0.0023 (9)0.0077 (9)0.0139 (7)
C50.0720 (13)0.0603 (11)0.0463 (9)0.0113 (9)0.0196 (9)0.0086 (8)
C60.0460 (8)0.0559 (9)0.0417 (8)0.0047 (7)0.0169 (7)0.0046 (7)
C70.0413 (7)0.0372 (6)0.0298 (6)0.0090 (5)0.0111 (5)0.0016 (5)
C80.0351 (6)0.0342 (6)0.0405 (7)0.0127 (5)0.0153 (5)0.0023 (5)
C90.0344 (6)0.0322 (6)0.0339 (6)0.0106 (5)0.0129 (5)0.0001 (5)
C100.0475 (8)0.0506 (8)0.0355 (7)0.0246 (7)0.0142 (6)0.0037 (6)
C110.0453 (7)0.0411 (7)0.0295 (6)0.0162 (6)0.0121 (5)0.0028 (5)
C120.0359 (7)0.0376 (6)0.0369 (7)0.0105 (5)0.0103 (5)0.0015 (5)
C130.0416 (7)0.0419 (7)0.0367 (7)0.0144 (6)0.0114 (6)0.0024 (5)
C140.0392 (7)0.0492 (8)0.0328 (6)0.0151 (6)0.0121 (5)0.0086 (5)
C150.0457 (8)0.0507 (9)0.0466 (8)0.0005 (7)0.0122 (7)0.0001 (7)
C160.0563 (10)0.0449 (8)0.0416 (8)0.0057 (7)0.0144 (7)0.0072 (6)
N10.0406 (6)0.0388 (6)0.0405 (6)0.0169 (5)0.0194 (5)0.0046 (5)
O10.0638 (8)0.0471 (6)0.0703 (8)0.0323 (6)0.0422 (6)0.0212 (5)
Cl10.0451 (2)0.0557 (3)0.0965 (4)0.00095 (18)0.0269 (2)0.0159 (2)
Cl20.0465 (2)0.0776 (3)0.0608 (3)0.0192 (2)0.0275 (2)0.0075 (2)
S10.03570 (19)0.0574 (2)0.0392 (2)0.01553 (16)0.00402 (14)0.00582 (15)
Geometric parameters (Å, º) top
C1—C91.3294 (19)C8—C91.4901 (18)
C1—S11.7508 (17)C9—C101.514 (2)
C1—H10.9300C10—C111.505 (2)
C2—C71.388 (2)C10—H10A0.9700
C2—C31.396 (2)C10—H10B0.9700
C2—S11.7642 (18)C11—C121.387 (2)
C3—C41.368 (3)C11—C161.389 (2)
C3—H30.9300C12—C131.383 (2)
C4—C51.376 (3)C12—Cl11.7336 (17)
C4—H40.9300C13—C141.375 (2)
C5—C61.387 (3)C13—H130.9300
C5—H50.9300C14—C151.377 (2)
C6—C71.385 (2)C14—Cl21.7295 (16)
C6—H60.9300C15—C161.384 (2)
C7—N11.4158 (19)C15—H150.9300
C8—O11.2350 (17)C16—H160.9300
C8—N11.3481 (19)N1—H1A0.8600
C9—C1—S1127.26 (11)C11—C10—H10A108.3
C9—C1—H1116.4C9—C10—H10A108.3
S1—C1—H1116.4C11—C10—H10B108.3
C7—C2—C3119.11 (15)C9—C10—H10B108.3
C7—C2—S1121.99 (12)H10A—C10—H10B107.4
C3—C2—S1118.67 (13)C12—C11—C16116.63 (14)
C4—C3—C2120.73 (17)C12—C11—C10123.35 (15)
C4—C3—H3119.6C16—C11—C10119.97 (14)
C2—C3—H3119.6C13—C12—C11122.51 (14)
C3—C4—C5120.14 (17)C13—C12—Cl1117.07 (12)
C3—C4—H4119.9C11—C12—Cl1120.42 (12)
C5—C4—H4119.9C14—C13—C12118.59 (14)
C4—C5—C6119.97 (18)C14—C13—H13120.7
C4—C5—H5120.0C12—C13—H13120.7
C6—C5—H5120.0C13—C14—C15121.28 (14)
C7—C6—C5120.20 (17)C13—C14—Cl2118.34 (12)
C7—C6—H6119.9C15—C14—Cl2120.38 (13)
C5—C6—H6119.9C14—C15—C16118.61 (16)
C6—C7—C2119.78 (14)C14—C15—H15120.7
C6—C7—N1117.04 (13)C16—C15—H15120.7
C2—C7—N1123.08 (13)C15—C16—C11122.33 (15)
O1—C8—N1118.83 (12)C15—C16—H16118.8
O1—C8—C9117.93 (12)C11—C16—H16118.8
N1—C8—C9123.23 (12)C8—N1—C7131.25 (11)
C1—C9—C8124.33 (13)C8—N1—H1A114.4
C1—C9—C10122.86 (12)C7—N1—H1A114.4
C8—C9—C10112.36 (11)C1—S1—C2101.45 (7)
C11—C10—C9115.75 (12)
C7—C2—C3—C42.3 (2)C16—C11—C12—C131.8 (2)
S1—C2—C3—C4172.38 (14)C10—C11—C12—C13175.75 (13)
C2—C3—C4—C50.6 (3)C16—C11—C12—Cl1177.66 (12)
C3—C4—C5—C60.6 (3)C10—C11—C12—Cl14.7 (2)
C4—C5—C6—C70.1 (3)C11—C12—C13—C141.8 (2)
C5—C6—C7—C21.6 (2)Cl1—C12—C13—C14177.71 (11)
C5—C6—C7—N1178.10 (15)C12—C13—C14—C150.1 (2)
C3—C2—C7—C62.8 (2)C12—C13—C14—Cl2179.09 (11)
S1—C2—C7—C6171.71 (12)C13—C14—C15—C161.9 (2)
C3—C2—C7—N1179.04 (14)Cl2—C14—C15—C16179.17 (13)
S1—C2—C7—N14.5 (2)C14—C15—C16—C111.8 (3)
S1—C1—C9—C87.0 (2)C12—C11—C16—C150.0 (2)
S1—C1—C9—C10178.71 (12)C10—C11—C16—C15177.70 (15)
O1—C8—C9—C1141.76 (16)O1—C8—N1—C7167.01 (16)
N1—C8—C9—C138.2 (2)C9—C8—N1—C713.1 (2)
O1—C8—C9—C1030.69 (19)C6—C7—N1—C8135.73 (17)
N1—C8—C9—C10149.37 (15)C2—C7—N1—C847.9 (2)
C1—C9—C10—C112.2 (2)C9—C1—S1—C251.65 (16)
C8—C9—C10—C11170.34 (13)C7—C2—S1—C158.57 (13)
C9—C10—C11—C1298.99 (18)C3—C2—S1—C1126.89 (13)
C9—C10—C11—C1683.49 (19)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10B···Cl10.972.643.103 (3)109
N1—H1A···O1i0.862.102.873 (2)149
Symmetry code: (i) x+2, y+1, z+2.

Experimental details

Crystal data
Chemical formulaC16H11Cl2NOS
Mr336.22
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)7.879 (5), 9.667 (5), 9.979 (5)
α, β, γ (°)89.052 (5), 78.161 (4), 83.647 (5)
V3)739.3 (7)
Z2
Radiation typeMo Kα
µ (mm1)0.58
Crystal size (mm)0.24 × 0.21 × 0.15
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.871, 0.917
No. of measured, independent and
observed [I > 2σ(I)] reflections
18415, 5225, 4013
Rint0.026
(sin θ/λ)max1)0.781
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.042, 0.123, 1.04
No. of reflections5225
No. of parameters190
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.55, 0.44

Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT (Bruker, 2004), SAINT and XPREP (Bruker, 2004), SHELXS97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10B···Cl10.972.643.103 (3)109
N1—H1A···O1i0.862.102.873 (2)149
Symmetry code: (i) x+2, y+1, z+2.
 

Footnotes

Additional correspondence author, e-mail: bhakthadoss@yahoo.com.

Acknowledgements

The authors thank Dr Babu Vargheese, SAIF, IIT, Madras, India, for the data collection.

References

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