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ISSN: 2056-9890

3,5-Bis(4-meth­oxy­phen­yl)-1H-1,2,4-triazole monohydrate

aCollege of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University, Jinan 250014, People's Republic of China
*Correspondence e-mail: yubindong@sdnu.edu.cn

(Received 24 April 2009; accepted 5 May 2009; online 14 May 2009)

In the title compound, C16H15N3O2·H2O, the two benzene rings and the triazole ring lie almost in the same plane, the triazole ring forming dihedral angles of 5.07 (9) and 5.80 (8)° with the benzene rings. In the crystal, there are three relatively strong inter­molecular O—H⋯N and N—H⋯O hydrogen bonds, which lead to the formation of a one-dimensional double chain running parallel to the a axis. Weak ππ inter­actions between the benzene rings of neighboring chains with a centroid–centroid distance of 3.893 (4) Å result in the formation of layers parallel to the ac plane.

Related literature

For the biological activity and pharmaceutical applications of compounds containing triazole subunits, see: Chai et al. (2009[Chai, X.-Y., Zhang, J., Yu, S.-C., Hu, H.-G., Zou, Y., Zhao, Q.-J., Dan, Z.-G., Zhang, D.-Z. & Wu, Q.-Y. (2009). Bioorg. Med. Chem. Lett. 19, 1811-1814.]); Nadkarni et al. (2001[Nadkarni, B. A., Kamat, V. R. & Khadse, B. G. (2001). Arzneim. Forsch. 51,569-573.]); Zhan & Lou (2007[Zhan, T.-R. & Lou, H.-X. (2007). Carbohydr. Res. 342, 865-869.]). For triazole ring bond-length data, see; Claramunt et al. (2001[Claramunt, R. M., Lopez, C., Angeles, G. M., Dolores, O. M., Rosario, T. M., Pinilla, E., Alarcon, S. H., Alkorta, I. & Elguero, J. (2001). New J. Chem. 25, 1061-1068.]); Zhou et al. (2001[Zhou, X. J., Kovalev, E. G., Klug, J. T. & Khodorkovsky, V. (2001). Org. Lett. 3, 1725-1727.]); John (1998[John, A. D. (1998). Lang's Handbook of Chemistry, Vol. 4, pp. 39-41. New York: McGraw-Hill.]).

[Scheme 1]

Experimental

Crystal data
  • C16H15N3O2·H2O

  • Mr = 299.33

  • Triclinic, [P \overline 1]

  • a = 6.9948 (18) Å

  • b = 11.125 (3) Å

  • c = 11.184 (3) Å

  • α = 110.603 (4)°

  • β = 107.932 (3)°

  • γ = 95.690 (4)°

  • V = 753.8 (3) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 298 K

  • 0.40 × 0.20 × 0.19 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: none

  • 3854 measured reflections

  • 2651 independent reflections

  • 1993 reflections with I > 2σ(I)

  • Rint = 0.016

Refinement
  • R[F2 > 2σ(F2)] = 0.052

  • wR(F2) = 0.134

  • S = 1.05

  • 2651 reflections

  • 201 parameters

  • H-atom parameters constrained

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.25 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O3—H3A⋯N1 0.97 1.96 2.902 (2) 164
N2—H2⋯O3i 0.86 1.90 2.753 (2) 170
O3—H3B⋯N3ii 0.96 1.97 2.885 (2) 159
Symmetry codes: (i) -x, -y, -z+1; (ii) -x+1, -y, -z+1.

Data collection: SMART (Bruker, 2000[Bruker (2000). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2000[Bruker (2000). SMART and SAINT. 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

During the past decades, compounds containing triazole subunits have been intensively studied due to their diverse biological activities, such as antibacterial, antitumor, etc. and have become a central focus in the study of agricultural and medicinal chemicals (Chai et al., 2009; Nadkarni et al., 2001; Zhan et al., 2007). In a search for more effective antibacterial compounds, we have synthesized the title compound and determined its structure.

The molecular structure of the title compound is shown in Fig. 1. The two benzene rings and the triazole ring almost lie in the same plane. The corresponding dihedral angles of each benzene ring with the triazole ring are 5.07 (9) (between C2–C7 and N1–N3/C8/C9) and 5.80 (8)° (between N1–N3/C8/C9 and C10–C15), respectively. The bond lengths of the triazole ring are very similar to other 1H-1,2,4-triazole derivatives (Claramunt et al., 2001; Zhou et al., 2001). C8—N3 (1.365 (2) Å) and N1—N2 (1.359 (2) Å) are typical for carbon-nitrogen single bonds and nitrogen-nitrogen single bonds, and C8—N1 (1.323 (2) Å) and C9—N3 (1.330 (2) Å) correspond to typical carbon-nitrogen double bonds (John, 1998). C9—N2 (1.333 (2) Å) is a carbon-nitrogen single bond, but the bond length is markedly shorter than usual carbon-nitrogen single bonds and close to a double bond due to its conjugation with the C9—N3 double bond.

The packing of the molecules in the crystal structure is stabilized through N—H···O, O—H···O and ππ interactions. Water molecules act both as hydrogen-acceptor and as hydrogen-donor which leads to the formation of a one dimensional double chain running parallel to the a axis (Fig. 2, Table 1). The ring made up of C10 to C15 (with the centroid Cg1) is parallel to its symmetry related counterpart with a Cg1··· Cg1iii distance of 3.893 (4) Å [symmetry code: (iii)-x, -y, -z]. Adjacent chains are linked via these intermolecular ππ interactions between the Cg1 rings to form a two-dimentional layer parallel to the ac plane (Fig. 3).

Related literature top

For the biological activity and pharmaceutical applications of compounds containing triazole subunits, see: Chai et al. (2009); Nadkarni et al. (2001); Zhan et al. (2007). For triazole ring bond-length data, see; Claramunt et al. (2001); Zhou et al. (2001); John (1998).

Experimental top

A mixture of 4-methoxyphenylmethylenemalononitrile (20 mmol), hydrazine dihydrochloride (20 mmol) and hydrazine hydrate (60 mmol) in ethylene glycol (10 ml) was heated to 403 K with stirring for 3–4 h. After cooling to room temperature, the reaction mixture was diluted with water (20 ml). The precipitate was filtered, washed with water, dried and purified by column chromatography on silica gel using CH2Cl2 as the eluent to afford a white solid after evaporation of the solvent. The white solid was dissolved in ethanol and colourless crystals of the title compound were obtained on slow evaporation of the solvent at room temperature.

Refinement top

Hydrogen atoms attached to carbon were placed in geometrically idealized positions (Carene—H = 0.93 Å, Cmethyl—H = 0.96 Å) and refined using a riding model with isotropic displacement parameters Uiso = 1.2 (1.5 for methyl groups) Ueq(C). The H atoms attached to N and O atoms were located by Fourier difference synthesis and refined using a riding model with isotropic displacement parameters of Uiso = 1.2 Ueq(N) and Uiso = 1.5 Ueq(O).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); 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. The molecular structure, with atom labels and 30% probability displacement ellipsoids.
[Figure 2] Fig. 2. View of a one dimensional double chain of the title structure. Hydrogen bonds are shown as dashed lines. H atoms not involved in hydrogen bonding have been omitted for clarity.
[Figure 3] Fig. 3. The crystal packing of the title compound via weak ππ interactions. The distance of centroids is 3.893 (4) Å (Dashed lines: hydrogen bonds; broken lines: ππ interactions.) [symmetry code: (iii) -x, -y, -z].
3,5-Bis(4-methoxyphenyl)-1H-1,2,4-triazole monohydrate top
Crystal data top
C16H15N3O2·H2OZ = 2
Mr = 299.33F(000) = 316
Triclinic, P1Dx = 1.319 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 6.9948 (18) ÅCell parameters from 1120 reflections
b = 11.125 (3) Åθ = 2.2–24.0°
c = 11.184 (3) ŵ = 0.09 mm1
α = 110.603 (4)°T = 298 K
β = 107.932 (3)°Block, colourless
γ = 95.690 (4)°0.40 × 0.20 × 0.19 mm
V = 753.8 (3) Å3
Data collection top
Bruker SMART CCD area-detector
diffractometer
1993 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.016
Graphite monochromatorθmax = 25.1°, θmin = 2.0°
phi and ω scansh = 48
3854 measured reflectionsk = 1311
2651 independent reflectionsl = 1213
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)] = 0.052Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.134H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0708P)2 + 0.0124P]
where P = (Fo2 + 2Fc2)/3
2651 reflections(Δ/σ)max = 0.001
201 parametersΔρmax = 0.17 e Å3
0 restraintsΔρmin = 0.25 e Å3
Crystal data top
C16H15N3O2·H2Oγ = 95.690 (4)°
Mr = 299.33V = 753.8 (3) Å3
Triclinic, P1Z = 2
a = 6.9948 (18) ÅMo Kα radiation
b = 11.125 (3) ŵ = 0.09 mm1
c = 11.184 (3) ÅT = 298 K
α = 110.603 (4)°0.40 × 0.20 × 0.19 mm
β = 107.932 (3)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
1993 reflections with I > 2σ(I)
3854 measured reflectionsRint = 0.016
2651 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0520 restraints
wR(F2) = 0.134H-atom parameters constrained
S = 1.05Δρmax = 0.17 e Å3
2651 reflectionsΔρmin = 0.25 e Å3
201 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
C11.3626 (4)0.5268 (3)0.8502 (3)0.0831 (8)
H1A1.41710.45390.80910.125*
H1B1.46720.58870.93490.125*
H1C1.31990.56960.78860.125*
C21.0219 (3)0.3942 (2)0.7668 (2)0.0493 (5)
C30.8500 (3)0.3622 (2)0.7965 (2)0.0506 (5)
H30.85500.39780.88640.061*
C40.6729 (3)0.27787 (19)0.6928 (2)0.0447 (5)
H40.55850.25710.71370.054*
C50.6599 (3)0.22255 (18)0.55736 (19)0.0394 (5)
C60.8338 (3)0.2549 (2)0.5307 (2)0.0524 (6)
H60.82920.21930.44090.063*
C71.0141 (3)0.3388 (2)0.6341 (2)0.0578 (6)
H71.13000.35760.61380.069*
C80.4703 (3)0.13404 (18)0.44671 (18)0.0368 (4)
C90.2616 (3)0.00131 (18)0.24816 (19)0.0379 (5)
C100.1682 (3)0.08505 (18)0.10190 (19)0.0393 (5)
C110.2847 (3)0.0918 (2)0.0197 (2)0.0519 (6)
H110.41990.04170.05870.062*
C120.2030 (3)0.1712 (2)0.1177 (2)0.0598 (6)
H120.28280.17410.17110.072*
C130.0040 (3)0.2468 (2)0.1776 (2)0.0503 (5)
C140.1137 (3)0.2420 (2)0.0979 (2)0.0539 (6)
H140.24810.29320.13720.065*
C150.0313 (3)0.1610 (2)0.0403 (2)0.0499 (5)
H150.11210.15760.09320.060*
C160.2664 (4)0.4015 (2)0.3827 (2)0.0745 (8)
H16A0.28510.46290.34250.112*
H16B0.29150.44910.47830.112*
H16C0.36170.34550.37350.112*
N10.2943 (2)0.10899 (16)0.46420 (16)0.0437 (4)
N20.1636 (2)0.02456 (16)0.33612 (16)0.0424 (4)
H20.03540.00920.31480.051*
N30.4569 (2)0.06990 (15)0.31449 (15)0.0404 (4)
O10.0613 (2)0.32325 (16)0.31464 (15)0.0726 (5)
O21.1911 (2)0.48023 (16)0.87639 (15)0.0693 (5)
O30.2326 (2)0.08148 (15)0.69915 (14)0.0540 (4)
H3A0.23390.10080.62150.100*
H3B0.33140.02940.71420.100*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0486 (14)0.087 (2)0.079 (2)0.0039 (13)0.0166 (13)0.0062 (16)
C20.0446 (12)0.0498 (13)0.0414 (12)0.0095 (10)0.0117 (10)0.0088 (10)
C30.0611 (14)0.0521 (13)0.0338 (12)0.0116 (10)0.0194 (10)0.0106 (10)
C40.0481 (12)0.0474 (12)0.0392 (12)0.0092 (9)0.0215 (9)0.0139 (10)
C50.0434 (11)0.0407 (11)0.0372 (11)0.0122 (9)0.0182 (9)0.0157 (9)
C60.0494 (13)0.0623 (14)0.0362 (12)0.0052 (10)0.0205 (10)0.0075 (10)
C70.0457 (12)0.0662 (15)0.0519 (14)0.0043 (11)0.0238 (11)0.0103 (12)
C80.0401 (10)0.0403 (11)0.0340 (11)0.0121 (8)0.0173 (8)0.0157 (9)
C90.0373 (10)0.0439 (11)0.0381 (11)0.0114 (9)0.0175 (9)0.0191 (10)
C100.0417 (11)0.0419 (11)0.0351 (11)0.0075 (9)0.0147 (9)0.0166 (9)
C110.0477 (12)0.0585 (14)0.0380 (12)0.0078 (10)0.0166 (10)0.0109 (11)
C120.0638 (15)0.0636 (15)0.0438 (13)0.0072 (12)0.0258 (11)0.0130 (12)
C130.0615 (14)0.0427 (12)0.0346 (12)0.0000 (10)0.0095 (10)0.0123 (10)
C140.0437 (12)0.0563 (14)0.0495 (14)0.0016 (10)0.0101 (10)0.0170 (11)
C150.0397 (11)0.0608 (14)0.0475 (13)0.0072 (10)0.0173 (10)0.0202 (11)
C160.0777 (17)0.0606 (16)0.0490 (15)0.0158 (13)0.0073 (12)0.0160 (13)
N10.0420 (9)0.0526 (10)0.0366 (10)0.0123 (8)0.0178 (8)0.0148 (8)
N20.0329 (8)0.0539 (10)0.0385 (10)0.0071 (7)0.0147 (7)0.0160 (8)
N30.0370 (9)0.0472 (10)0.0338 (9)0.0064 (7)0.0148 (7)0.0124 (8)
O10.0834 (12)0.0678 (11)0.0387 (10)0.0165 (9)0.0129 (8)0.0074 (8)
O20.0503 (9)0.0764 (12)0.0499 (10)0.0021 (8)0.0085 (7)0.0033 (9)
O30.0439 (8)0.0746 (10)0.0513 (9)0.0170 (7)0.0265 (7)0.0255 (8)
Geometric parameters (Å, º) top
C1—O21.412 (3)C9—C101.462 (3)
C1—H1A0.9600C10—C151.379 (3)
C1—H1B0.9600C10—C111.393 (3)
C1—H1C0.9600C11—C121.368 (3)
C2—O21.370 (2)C11—H110.9300
C2—C71.373 (3)C12—C131.375 (3)
C2—C31.389 (3)C12—H120.9300
C3—C41.370 (3)C13—O11.362 (2)
C3—H30.9300C13—C141.380 (3)
C4—C51.390 (3)C14—C151.379 (3)
C4—H40.9300C14—H140.9300
C5—C61.381 (3)C15—H150.9300
C5—C81.461 (3)C16—O11.418 (3)
C6—C71.381 (3)C16—H16A0.9600
C6—H60.9300C16—H16B0.9600
C7—H70.9300C16—H16C0.9600
C8—N11.323 (2)N1—N21.359 (2)
C8—N31.365 (2)N2—H20.8600
C9—N31.330 (2)O3—H3A0.9678
C9—N21.333 (2)O3—H3B0.9583
O2—C1—H1A109.5C15—C10—C9123.15 (18)
O2—C1—H1B109.5C11—C10—C9119.01 (17)
H1A—C1—H1B109.5C12—C11—C10120.85 (18)
O2—C1—H1C109.5C12—C11—H11119.6
H1A—C1—H1C109.5C10—C11—H11119.6
H1B—C1—H1C109.5C11—C12—C13120.7 (2)
O2—C2—C7124.66 (19)C11—C12—H12119.7
O2—C2—C3115.73 (19)C13—C12—H12119.7
C7—C2—C3119.61 (19)O1—C13—C12115.9 (2)
C4—C3—C2119.73 (19)O1—C13—C14124.71 (19)
C4—C3—H3120.1C12—C13—C14119.4 (2)
C2—C3—H3120.1C15—C14—C13119.77 (19)
C3—C4—C5121.72 (19)C15—C14—H14120.1
C3—C4—H4119.1C13—C14—H14120.1
C5—C4—H4119.1C10—C15—C14121.47 (19)
C6—C5—C4117.40 (18)C10—C15—H15119.3
C6—C5—C8120.93 (17)C14—C15—H15119.3
C4—C5—C8121.67 (17)O1—C16—H16A109.5
C7—C6—C5121.7 (2)O1—C16—H16B109.5
C7—C6—H6119.2H16A—C16—H16B109.5
C5—C6—H6119.2O1—C16—H16C109.5
C2—C7—C6119.84 (19)H16A—C16—H16C109.5
C2—C7—H7120.1H16B—C16—H16C109.5
C6—C7—H7120.1C8—N1—N2102.97 (15)
N1—C8—N3113.34 (16)C9—N2—N1110.53 (15)
N1—C8—C5123.47 (16)C9—N2—H2124.7
N3—C8—C5123.19 (16)N1—N2—H2124.7
N3—C9—N2109.15 (17)C9—N3—C8104.00 (15)
N3—C9—C10125.62 (17)C13—O1—C16118.50 (18)
N2—C9—C10125.23 (17)C2—O2—C1118.09 (18)
C15—C10—C11117.84 (18)H3A—O3—H3B107.8
O2—C2—C3—C4179.32 (17)C11—C12—C13—O1179.37 (19)
C7—C2—C3—C41.4 (3)C11—C12—C13—C140.1 (3)
C2—C3—C4—C50.1 (3)O1—C13—C14—C15179.8 (2)
C3—C4—C5—C60.5 (3)C12—C13—C14—C150.4 (3)
C3—C4—C5—C8179.20 (17)C11—C10—C15—C140.4 (3)
C4—C5—C6—C70.1 (3)C9—C10—C15—C14179.59 (18)
C8—C5—C6—C7179.80 (18)C13—C14—C15—C100.7 (3)
O2—C2—C7—C6178.80 (19)N3—C8—N1—N20.0 (2)
C3—C2—C7—C62.0 (3)C5—C8—N1—N2179.44 (16)
C5—C6—C7—C21.3 (3)N3—C9—N2—N10.6 (2)
C6—C5—C8—N1173.76 (19)C10—C9—N2—N1179.86 (16)
C4—C5—C8—N16.0 (3)C8—N1—N2—C90.35 (19)
C6—C5—C8—N35.6 (3)N2—C9—N3—C80.6 (2)
C4—C5—C8—N3174.69 (17)C10—C9—N3—C8179.88 (17)
N3—C9—C10—C15175.33 (18)N1—C8—N3—C90.4 (2)
N2—C9—C10—C155.2 (3)C5—C8—N3—C9179.81 (16)
N3—C9—C10—C114.6 (3)C12—C13—O1—C16178.8 (2)
N2—C9—C10—C11174.80 (18)C14—C13—O1—C161.8 (3)
C15—C10—C11—C120.1 (3)C7—C2—O2—C17.2 (3)
C9—C10—C11—C12179.88 (19)C3—C2—O2—C1173.6 (2)
C10—C11—C12—C130.4 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···N10.971.962.902 (2)164
N2—H2···O3i0.861.902.753 (2)170
O3—H3B···N3ii0.961.972.885 (2)159
Symmetry codes: (i) x, y, z+1; (ii) x+1, y, z+1.

Experimental details

Crystal data
Chemical formulaC16H15N3O2·H2O
Mr299.33
Crystal system, space groupTriclinic, P1
Temperature (K)298
a, b, c (Å)6.9948 (18), 11.125 (3), 11.184 (3)
α, β, γ (°)110.603 (4), 107.932 (3), 95.690 (4)
V3)753.8 (3)
Z2
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.40 × 0.20 × 0.19
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
3854, 2651, 1993
Rint0.016
(sin θ/λ)max1)0.597
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.052, 0.134, 1.05
No. of reflections2651
No. of parameters201
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.17, 0.25

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···N10.971.962.902 (2)163.7
N2—H2···O3i0.861.902.753 (2)169.6
O3—H3B···N3ii0.961.972.885 (2)158.9
Symmetry codes: (i) x, y, z+1; (ii) x+1, y, z+1.
 

Acknowledgements

The authors thank the National Natural Science Foundation of China (grant Nos. 20871076 and 20671060), the PhD Programs Foundation of the Ministry of Education of China (grant No. 200804450001) and the Shandong Natural Science Foundation (grant No. JQ200803) for support.

References

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