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ISSN: 2056-9890

Ethyl 5-methyl-1-(4-nitro­phen­yl)-1H-1,2,3-triazole-4-carboxyl­ate

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri, Mangalore 574 199, India
*Correspondence e-mail: hkfun@usm.my

(Received 18 August 2011; accepted 19 August 2011; online 27 August 2011)

In the title compound, C12H12N4O4, the 1,2,3-triazole ring and the nitro group form dihedral angles of 37.93 (5) and 8.97 (12)°, respectively, with the phenyl ring. The mol­ecular structure is stabilized by an intra­molecular C—H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, mol­ecules are linked by C—H⋯N hydrogen bonds into layers lying parallel to (100). The crystal structure is further consolidated by ππ [centroid–centroid distance = 3.6059 (6) Å] inter­actions.

Related literature

For general background to and the biological activity of 1,2,3-triazole derivatives, see: Sherement et al. (2004[Sherement, E. A., Tomanov, R. I., Trukhin, E. V. & Berestovitskaya, V. M. (2004). Russ. J. Org. Chem. 40, 594-595.]); Danoun et al. (1998[Danoun, S., Baziard-Mouysset, G., Stigliani, J., Payard, M., Selkti, M., Viossat, B. & Tomas, A. (1998). Heterocycl. Commun. 4, 45-51.]); Manfredini et al. (2000[Manfredini, S., Vicentini, C. B., Manfrini, M., Bianchi, N., Rutigliano, C., Mischiati, C. & Gambari, R. (2000). Bioorg. Med. Chem. 8, 2343-2346.]); Biagi et al. (2004[Biagi, G., Calderone, V., Giorgi, I., Livi, O., Martinotti, E., Martelli, A. & Nardi, A. (2004). Il Farmaco, 59, 397-404.]). For standard bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-S19.]). 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.]). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.]). For related structures, see: Fun, Quah, Chandrakantha et al. (2011[Fun, H.-K., Quah, C. K., Chandrakantha, B., Isloor, A. M. & Shetty, P. (2011). Acta Cryst. E67, o164.]); Fun, Quah, Nithinchandra et al. (2011[Fun, H.-K., Quah, C. K., Nithinchandra & Kalluraya, B. (2011). Acta Cryst. E67, o1005-o1006.]).

[Scheme 1]

Experimental

Crystal data
  • C12H12N4O4

  • Mr = 276.26

  • Monoclinic, P 21 /c

  • a = 13.5309 (3) Å

  • b = 7.3014 (2) Å

  • c = 12.6058 (3) Å

  • β = 99.574 (1)°

  • V = 1228.04 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 100 K

  • 0.50 × 0.16 × 0.16 mm

Data collection
  • Bruker SMART APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.944, Tmax = 0.982

  • 16800 measured reflections

  • 4469 independent reflections

  • 3699 reflections with I > 2σ(I)

  • Rint = 0.021

Refinement
  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.114

  • S = 1.03

  • 4469 reflections

  • 183 parameters

  • H-atom parameters constrained

  • Δρmax = 0.41 e Å−3

  • Δρmin = −0.30 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C1—H1A⋯N3i 0.95 2.59 3.5243 (12) 168
C5—H5A⋯N2ii 0.95 2.60 3.2347 (12) 125
C5—H5A⋯N3ii 0.95 2.54 3.4127 (12) 154
C10—H10B⋯O4 0.98 2.48 3.0936 (12) 120
Symmetry codes: (i) -x+1, -y, -z; (ii) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

1,2,3-Triazole and its derivatives had attracted considerable attention for the past few decades due to their chemotherapeutical value. Many 1,2,3-triazoles are found to be potent antimicrobial (Sherement et al., 2004) and antiviral agents. Some of them have exhibited antiproliferative and anticancer activities (Danoun et al., 1998). Some 1,2,3-triazoles are used as DNA cleaving agents (Manfredini et al., 2000) and potassium channel activators (Biagi et al., 2004). Prompted by the chemotherapeutic importance of 1,2,3-triazoles and its derivatives, we synthesized the title compound.

In the title molecule, Fig. 1, the 1,2,3-triazole ring (N1-N3/C7/C8, maximum deviation of 0.003 (1) Å at atoms N2 and N3) and the nitro group (O2/O3/N4) form dihedral angles of 37.93 (5) and 8.97 (12)°, respectively, with the phenyl ring (C1-C6). Bond lengths (Allen et al., 1987) and angles are within normal ranges and are comparable to related structures (Fun, Quah, Chandrakantha et al., 2011; Fun, Quah, Nithinchandra et al., 2011). The molecular structure is stabilized by an intramolecular C41-H10B···O4 hydrogen bond (Table 1), which generates an S(6) ring motif (Fig. 1, Bernstein et al., 1995).

In the crystal structure, Fig. 2, molecules are linked via intermolecular C1–H1A···N3, C5–H5A···N2 and C5–H5A···N3 hydrogen bonds (Table 1) into two-dimensional planes parallel to (100). π-π stacking interactions between the centroids of C1-C6 phenyl ring (Cg1) and N1-N3/C7/C8 triazole ring (Cg2), with Cg1···Cg2iii distance of 3.6059 (6) Å [symmetry code: (iii) 1-X,-1/2+Y,1/2-Z] are observed.

Related literature top

For general background to and the biological activity of 1,2,3-triazole derivatives, see: Sherement et al. (2004); Danoun et al. (1998); Manfredini et al. (2000); Biagi et al. (2004). For standard bond-length data, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986). For related structures, see: Fun, Quah, Chandrakantha et al. (2011); Fun, Quah, Nithinchandra et al. (2011).

Experimental top

1-Azido-4-nitrobenzene (15 g) was treated with ethyl acetoacetate (8.3 g) in methanol (75 ml) and the mixture was cooled to 273 K. Sodium methoxide (3.5 g) was added under inert atmosphere to the above mixture and stirred at ambient temperature for 8 h. Progress of the reaction was monitored by TLC (ethyl acetate/n-hexane, 2:3, v/v). After completion of the reaction, the mixture was poured on to ice cold water. The precipitated solid was filtered, washed with water and recrystallized from methanol. Colourless plates of (I) were obtained from DMF by slow evaporation.

Refinement top

All H atoms were positioned geometrically and refined using a riding model with C–H = 0.95-0.99 Å and Uiso(H) = 1.2 or 1.5 Ueq(C). A rotating-group model was applied for the methyl groups.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound showing 50% probability displacement ellipsoids for non-H atoms. The intramolecular hydrogen bond is shown as a dashed line.
[Figure 2] Fig. 2. The crystal structure of the title compound, viewed along the b axis. H atoms not involved in hydrogen bonds (dashed lines) have been omitted for clarity.
Ethyl 5-methyl-1-(4-nitrophenyl)-1H-1,2,3-triazole-4-carboxylate top
Crystal data top
C12H12N4O4F(000) = 576
Mr = 276.26Dx = 1.494 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 8459 reflections
a = 13.5309 (3) Åθ = 3.1–32.6°
b = 7.3014 (2) ŵ = 0.12 mm1
c = 12.6058 (3) ÅT = 100 K
β = 99.574 (1)°Plate, colourless
V = 1228.04 (5) Å30.50 × 0.16 × 0.16 mm
Z = 4
Data collection top
Bruker SMART APEXII CCD
diffractometer
4469 independent reflections
Radiation source: fine-focus sealed tube3699 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.021
ϕ and ω scansθmax = 32.6°, θmin = 3.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 2018
Tmin = 0.944, Tmax = 0.982k = 118
16800 measured reflectionsl = 1919
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) = 0.114H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0579P)2 + 0.3698P]
where P = (Fo2 + 2Fc2)/3
4469 reflections(Δ/σ)max = 0.001
183 parametersΔρmax = 0.41 e Å3
0 restraintsΔρmin = 0.30 e Å3
Crystal data top
C12H12N4O4V = 1228.04 (5) Å3
Mr = 276.26Z = 4
Monoclinic, P21/cMo Kα radiation
a = 13.5309 (3) ŵ = 0.12 mm1
b = 7.3014 (2) ÅT = 100 K
c = 12.6058 (3) Å0.50 × 0.16 × 0.16 mm
β = 99.574 (1)°
Data collection top
Bruker SMART APEXII CCD
diffractometer
4469 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
3699 reflections with I > 2σ(I)
Tmin = 0.944, Tmax = 0.982Rint = 0.021
16800 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.114H-atom parameters constrained
S = 1.03Δρmax = 0.41 e Å3
4469 reflectionsΔρmin = 0.30 e Å3
183 parameters
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
O10.17538 (5)0.16665 (10)0.05384 (5)0.01804 (15)
O20.81492 (6)0.19872 (12)0.56912 (6)0.02603 (18)
O30.88912 (6)0.04601 (13)0.45702 (7)0.02874 (19)
O40.14766 (5)0.02184 (11)0.09686 (6)0.02182 (16)
N10.45814 (6)0.12739 (11)0.18124 (6)0.01308 (15)
N20.46803 (6)0.17529 (12)0.07841 (6)0.01609 (16)
N30.37872 (6)0.17308 (12)0.02083 (6)0.01568 (16)
N40.81564 (6)0.12105 (13)0.48264 (7)0.01954 (17)
C10.63468 (7)0.05446 (13)0.22772 (7)0.01570 (17)
H1A0.63360.01130.15640.019*
C20.72344 (7)0.05470 (13)0.30098 (7)0.01654 (17)
H2A0.78410.01260.28070.020*
C30.72162 (7)0.11789 (13)0.40463 (7)0.01516 (17)
C40.63467 (7)0.17883 (13)0.43757 (7)0.01519 (17)
H4A0.63580.21970.50930.018*
C50.54574 (7)0.17947 (13)0.36424 (7)0.01414 (16)
H5A0.48520.22090.38500.017*
C60.54695 (6)0.11829 (13)0.25977 (7)0.01296 (16)
C70.36061 (6)0.09299 (12)0.18864 (7)0.01266 (16)
C80.31097 (7)0.12254 (13)0.08482 (7)0.01365 (16)
C90.20306 (7)0.09756 (13)0.04465 (7)0.01549 (17)
C100.32346 (7)0.03491 (14)0.28808 (7)0.01660 (18)
H10A0.37490.03890.33270.025*
H10B0.26240.03810.26860.025*
H10C0.30870.14340.32840.025*
C110.06813 (7)0.14784 (16)0.09678 (8)0.0212 (2)
H11A0.02760.19410.04400.025*
H11B0.05100.01750.11160.025*
C120.04675 (8)0.25753 (17)0.19890 (8)0.0252 (2)
H12A0.02430.24590.23010.038*
H12B0.08790.21160.25020.038*
H12C0.06270.38660.18300.038*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0132 (3)0.0239 (4)0.0165 (3)0.0003 (3)0.0008 (2)0.0035 (3)
O20.0228 (4)0.0363 (5)0.0175 (3)0.0044 (3)0.0011 (3)0.0009 (3)
O30.0157 (3)0.0370 (5)0.0330 (4)0.0053 (3)0.0024 (3)0.0051 (4)
O40.0167 (3)0.0304 (4)0.0189 (3)0.0049 (3)0.0043 (2)0.0031 (3)
N10.0132 (3)0.0159 (4)0.0106 (3)0.0003 (3)0.0035 (2)0.0001 (3)
N20.0153 (3)0.0219 (4)0.0116 (3)0.0003 (3)0.0039 (3)0.0019 (3)
N30.0146 (3)0.0198 (4)0.0130 (3)0.0003 (3)0.0036 (3)0.0011 (3)
N40.0155 (4)0.0227 (4)0.0197 (4)0.0016 (3)0.0009 (3)0.0060 (3)
C10.0166 (4)0.0165 (4)0.0150 (4)0.0002 (3)0.0056 (3)0.0009 (3)
C20.0143 (4)0.0169 (4)0.0194 (4)0.0013 (3)0.0057 (3)0.0007 (3)
C30.0136 (4)0.0156 (4)0.0159 (4)0.0009 (3)0.0013 (3)0.0030 (3)
C40.0159 (4)0.0164 (4)0.0133 (3)0.0003 (3)0.0027 (3)0.0012 (3)
C50.0141 (4)0.0158 (4)0.0130 (3)0.0006 (3)0.0037 (3)0.0001 (3)
C60.0130 (4)0.0132 (4)0.0128 (3)0.0004 (3)0.0028 (3)0.0008 (3)
C70.0136 (4)0.0121 (4)0.0129 (3)0.0009 (3)0.0041 (3)0.0005 (3)
C80.0141 (4)0.0152 (4)0.0124 (3)0.0004 (3)0.0042 (3)0.0003 (3)
C90.0149 (4)0.0175 (4)0.0142 (4)0.0006 (3)0.0027 (3)0.0014 (3)
C100.0176 (4)0.0198 (4)0.0134 (4)0.0026 (3)0.0057 (3)0.0010 (3)
C110.0130 (4)0.0282 (5)0.0213 (4)0.0002 (4)0.0007 (3)0.0024 (4)
C120.0207 (5)0.0312 (6)0.0220 (4)0.0025 (4)0.0015 (4)0.0047 (4)
Geometric parameters (Å, º) top
O1—C91.3348 (11)C4—C51.3901 (12)
O1—C111.4685 (11)C4—H4A0.9500
O2—N41.2303 (12)C5—C61.3933 (12)
O3—N41.2246 (12)C5—H5A0.9500
O4—C91.2103 (12)C7—C81.3849 (12)
N1—C71.3616 (11)C7—C101.4878 (12)
N1—N21.3705 (10)C8—C91.4751 (13)
N1—C61.4258 (11)C10—H10A0.9800
N2—N31.3022 (11)C10—H10B0.9800
N3—C81.3686 (11)C10—H10C0.9800
N4—C31.4730 (12)C11—C121.5029 (14)
C1—C21.3879 (13)C11—H11A0.9900
C1—C61.3962 (13)C11—H11B0.9900
C1—H1A0.9500C12—H12A0.9800
C2—C31.3897 (13)C12—H12B0.9800
C2—H2A0.9500C12—H12C0.9800
C3—C41.3846 (13)
C9—O1—C11114.50 (8)N1—C7—C8103.28 (7)
C7—N1—N2111.11 (7)N1—C7—C10125.27 (8)
C7—N1—C6131.17 (7)C8—C7—C10131.44 (8)
N2—N1—C6117.71 (7)N3—C8—C7109.38 (8)
N3—N2—N1107.24 (7)N3—C8—C9123.56 (8)
N2—N3—C8108.98 (7)C7—C8—C9127.01 (8)
O3—N4—O2124.49 (9)O4—C9—O1125.10 (9)
O3—N4—C3117.77 (9)O4—C9—C8122.48 (8)
O2—N4—C3117.74 (8)O1—C9—C8112.41 (8)
C2—C1—C6119.36 (8)C7—C10—H10A109.5
C2—C1—H1A120.3C7—C10—H10B109.5
C6—C1—H1A120.3H10A—C10—H10B109.5
C1—C2—C3118.52 (8)C7—C10—H10C109.5
C1—C2—H2A120.7H10A—C10—H10C109.5
C3—C2—H2A120.7H10B—C10—H10C109.5
C4—C3—C2122.51 (8)O1—C11—C12107.67 (8)
C4—C3—N4118.52 (8)O1—C11—H11A110.2
C2—C3—N4118.97 (8)C12—C11—H11A110.2
C3—C4—C5119.11 (8)O1—C11—H11B110.2
C3—C4—H4A120.4C12—C11—H11B110.2
C5—C4—H4A120.4H11A—C11—H11B108.5
C4—C5—C6118.85 (8)C11—C12—H12A109.5
C4—C5—H5A120.6C11—C12—H12B109.5
C6—C5—H5A120.6H12A—C12—H12B109.5
C5—C6—C1121.66 (8)C11—C12—H12C109.5
C5—C6—N1120.02 (8)H12A—C12—H12C109.5
C1—C6—N1118.27 (8)H12B—C12—H12C109.5
C7—N1—N2—N30.42 (10)C7—N1—C6—C1142.62 (10)
C6—N1—N2—N3179.36 (8)N2—N1—C6—C136.07 (12)
N1—N2—N3—C80.58 (10)N2—N1—C7—C80.07 (10)
C6—C1—C2—C30.41 (14)C6—N1—C7—C8178.83 (9)
C1—C2—C3—C40.58 (14)N2—N1—C7—C10179.02 (9)
C1—C2—C3—N4179.20 (8)C6—N1—C7—C100.27 (15)
O3—N4—C3—C4171.06 (9)N2—N3—C8—C70.56 (11)
O2—N4—C3—C48.86 (13)N2—N3—C8—C9177.07 (9)
O3—N4—C3—C29.16 (13)N1—C7—C8—N30.28 (10)
O2—N4—C3—C2170.93 (9)C10—C7—C8—N3179.30 (9)
C2—C3—C4—C50.85 (14)N1—C7—C8—C9177.24 (9)
N4—C3—C4—C5178.93 (8)C10—C7—C8—C91.78 (17)
C3—C4—C5—C60.12 (14)C11—O1—C9—O41.16 (14)
C4—C5—C6—C10.87 (14)C11—O1—C9—C8179.05 (8)
C4—C5—C6—N1176.36 (8)N3—C8—C9—O4166.28 (9)
C2—C1—C6—C51.14 (14)C7—C8—C9—O410.92 (16)
C2—C1—C6—N1176.14 (8)N3—C8—C9—O113.51 (13)
C7—N1—C6—C540.05 (14)C7—C8—C9—O1169.29 (9)
N2—N1—C6—C5141.26 (9)C9—O1—C11—C12171.11 (9)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1A···N3i0.952.593.5243 (12)168
C5—H5A···N2ii0.952.603.2347 (12)125
C5—H5A···N3ii0.952.543.4127 (12)154
C10—H10B···O40.982.483.0936 (12)120
Symmetry codes: (i) x+1, y, z; (ii) x, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC12H12N4O4
Mr276.26
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)13.5309 (3), 7.3014 (2), 12.6058 (3)
β (°) 99.574 (1)
V3)1228.04 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.12
Crystal size (mm)0.50 × 0.16 × 0.16
Data collection
DiffractometerBruker SMART APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.944, 0.982
No. of measured, independent and
observed [I > 2σ(I)] reflections
16800, 4469, 3699
Rint0.021
(sin θ/λ)max1)0.759
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.114, 1.03
No. of reflections4469
No. of parameters183
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.41, 0.30

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1A···N3i0.952.593.5243 (12)168
C5—H5A···N2ii0.952.603.2347 (12)125
C5—H5A···N3ii0.952.543.4127 (12)154
C10—H10B···O40.982.483.0936 (12)120
Symmetry codes: (i) x+1, y, z; (ii) x, y+1/2, z+1/2.
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009

§Thomson Reuters ResearcherID: A-5525-2009

Acknowledgements

HKF and CKQ thank Universiti Sains Malaysia for the Research University Grant (No. 1001/PFIZIK/811160).

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