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Journal logoIUCrDATA
ISSN: 2414-3146

3-(2-Chloro­pyridin-3-yl)quinazoline-2,4(1H,3H)-dione chloro­form monosolvate

aThe German University in Cairo, Department of Pharmaceutical Chemistry, New Cairo City, 11835 Cairo, Egypt, and bInstitute of Pharmacy and Food Chemistry, Wuerzburg University, 97074 Wuerzburg, Germany
*Correspondence e-mail: darius.zlotos@guc.edu.eg

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 9 April 2017; accepted 18 April 2017; online 28 April 2017)

The solvated title compound, C13H8ClN3O2·CHCl3, is a product of a condensation reaction between 2-amino-N-(2-chloro­pyridin-3-yl)benzamide and phosgene. The presence of the chlorine substituent in the pyridine ring forces the latter to adopt a nearly perpendicular orientation relative to the planar quinazoline ring (r.m.s. deviation = 0.04 Å), the two ring systems being inclined to one another by 84.28 (9)°. In the crystal, mol­ecules are linked by pairs of N—H⋯O hydrogen bonds, forming inversion dimers with an R22(8) ring motif. The dimers are linked by C—H⋯O hydrogen bonds, forming ribbons propagating along the a-axis direction. The chloro­form solvent mol­ecules are linked to the organic mol­ecule by C—H⋯N hydrogen bonds.

3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

The title compound results from our ongoing research aimed at the development of subtype-selective ligands for muscarinic receptors (Tahtaoui et al., 2004[Tahtaoui, C., Parrot, I., Klotz, P., Guillier, F., Galzi, J.-C., Hibert, M. & Ilien, B. (2004). J. Med. Chem. 47, 4300-4315.]; Mohr et al., 2010[Mohr, K., Tränkle, C., Kostenis, E., Barocelli, E., De Amici, M. & Holzgrabe, U. (2010). Br. J. Pharmacol. 159, 997-1008.]). It was isolated as a side-product in the course of the synthesis of AFDX-type allosteric modulators of muscarinic M2 receptors (Mohr et al., 2004[Mohr, M., Heller, E., Ataie, A., Mohr, K. & Holzgrabe, U. (2004). J. Med. Chem. 47, 3324-3327.]). Specifically, the incomplete condensation between ethyl 2-aminobenzoate and 3-amino-2-chloro­pyridine (Holzgrabe & Heller, 2003[Holzgrabe, U. & Heller, E. (2003). Tetrahedron, 59, 781-787.]) gave the ring-opened 2-amino-N-(2-chloro­pyridin-3-yl)benzamide (1) in 23% yield. This compound, (1), was subjected to condensation with phosgene giving the title compound (2) in 85% yield. This two-step approach is of general inter­est for the synthesis of differently substituted (1H,3H)-quinazoline-2,4-diones.

The mol­ecular structure of the title compound (2), which crystallized as a chloro­form monosolvate, is shown in Fig. 1[link]. The pyridine ring (N1/C1–C5) is nearly perpendicular to the planar quinazoline ring (N2/N3/C6–C13; r.m.s. deviation = 0.04 Å), making a dihedral angle of 84.28 (9)°.

[Figure 1]
Figure 1
The mol­ecular structure of the solvated title compound, (2)·CHCl3, with the atom labelling and displacement ellipsoids drawn at the 50% probability level.

In the crystal, mol­ecules are linked by pairs of N—H⋯O hydrogen bonds forming inversion dimers, with an R22(8) ring motif (Fig. 2[link] and Table 1[link]). The chloro­form solvate mol­ecules are linked to the organic mol­ecule by C—H⋯N hydrogen bonds, and the dimers are linked by C—H⋯O hydrogen bonds, forming ribbons propagating along the a-axis direction (Fig. 2[link] and Table 1[link]).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N3—H3⋯O1i 0.88 1.91 2.791 (3) 175
C14—H14⋯N1ii 1.00 2.39 3.200 (3) 137
C3—H3A⋯O2iii 0.95 2.48 3.123 (3) 125
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) x, y-1, z; (iii) x+1, y, z.
[Figure 2]
Figure 2
A view along the c axis of the crystal packing of the solvated title compound, (2)·CHCl3. The hydrogen bonds are shown as dashed lines (see Table 1[link]). For clarity, only the H atoms involved in hydrogen bonding have been included.

Synthesis and crystallization

2-Amino-N-(2-chloro­pyridin-3-yl)benzamide (1).

3-Amino-2-chloro­pyridine (2.57 g, 20.0 mmol), ethyl 2-amino­benzoate (3.39 g, 20.5 mmol) and KOtBu (7.29 g, 65.0 mmol) were suspended in dry 1,4-dioxane (100 ml) under argon. The mixture was heated by microwaves (gradient of heating: 2 min to 333 K; holding time: 10 min at 333 K; gradient of heating: 3 min from 333–373 K; holding time: 2.5 h at 373 K). After cooling to 298 K, the solution was treated with 1 M NaH2PO4 (60 ml) and stirred for 30 min. The dioxane was evaporated in vacuo and the residue was treated with 50 ml water. The solid obtained was filtered and dried. The product (1) was then purified by silica chromatography (ethyl acetate/petroleum ether 1:1, Rf = 0.78), giving a pale-yellow solid (yield: 1.16 g, 23.3%; m.p. 477.3 K). 1H NMR (400 MHz, DMSO-d6) δ 9.89 (1H, br, N—H), 8.29 (1H, dd, J = 4.7, 1.8 Hz), 8.07 (1H, dd, J = 7.9, 1.8 Hz), 7.74 (1H, dd, J = 8.1, 1.5 Hz), 7.49 (1H, dd, J = 7.9, 4.7 Hz), 7.24 (1H, ddd, J = 8.4, 7.1, 1.5 Hz), 6.79 (1H, dd, J = 8.4, 1.2 Hz), 6.62 (1H, ddd, J = 8.1, 7.1, 1.2 Hz), 6.47 (2H, br, NH2). 13C NMR (100 MHz, DMSO-d6) δ 168.27 (C= O), 150.73, 146.71 (C—Cl), 146.68 (CH), 136.96 (C), 133.22 (C), 132.82 (C), 129.25 (C), 123.85 (CH), 117.22 (C), 115.35 (C), 113.86 (C). IR (ATR, cm−1): 3433 (NH), 3330, 3286 (NH2), 3073 (CH), 1644 (C=O amide), 1616, 1578, 1569, 1503, 1486, 1391, 802, 743, 735. MS (ESI): m/z (%): 248.2 (M+1).

3-(2-Chloro­pyridin-3-yl)quinazoline-2,4-(1H,3H)dione (2).

Compound (1) (4.22 g, 20.0 mmol) and Hueunig's base (7.0 ml, 40.0 mmol) were dissolved in dry 1,4-dioxane (150 ml) under argon. A solution of 20% phosgene in toluene (18.5 ml, 35.0 mmol) was added dropwise over 30 min. The solution was heated using microwaves (gradient of heating: 3 min to 358 K; holding time: 2 h at 358 K). After cooling to 298 K, the mixture was quenched with 1.0 M NaH2PO4 (100 ml) and stirred for 1 h at room temperature. The dioxane was evap­orated and the solid obtained was filtered by suction and dried over P4O10, giving a white solid (yield: 4.68 g, 85.5%; m.p. 510.6 K). The product was recrystallized from chloro­form giving colourless block-like crystals of the title compound (2). 1H NMR (400 MHz, CDCl3) δ 10.52 (1H, br, N—H), 8.56 (1H, dd, J = 4.8, 1.8 Hz), 8.15 (1H, dd, J = 7.9, 1.1 Hz), 7.76 (1H, dd, J = 7.8, 1.8 Hz), 7.61 (1H, ddd, J = 8.1, 7.0, 1.1 Hz), 7.46 (1H, dd, J = 7.8, 4.8 Hz), 7.27 (1H, ddd, J = 7.9, 7.0, 1.0 Hz), 7.02 (1H, dd, J = 8.1, 1.0 Hz). 13C NMR (100 MHz, CDCl3) δ 161.58 (C=O), 150.95 (C=O), 150.40 (C—Cl), 149.94 (CH), 139.64 (C), 138.87 (C), 135.94 (C), 129.94 (C), 128.73 (C), 123.99 (C), 123.39 (CH), 115.70 (C), 114.34 (C). IR (ATR, cm−1): 3348 (NH), 3072 (CH), 1680 (C=O), 1730 (C=O), 1580, 734. MS (ESI): m/z (%): 274.6 (M+1).

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link].

Table 2
Experimental details

Crystal data
Chemical formula C13H8ClN3O2·CHCl3
Mr 393.04
Crystal system, space group Monoclinic, P21/c
Temperature (K) 100
a, b, c (Å) 5.6382 (11), 13.622 (3), 20.662 (4)
β (°) 92.289 (6)
V3) 1585.7 (5)
Z 4
Radiation type Mo Kα
μ (mm−1) 0.76
Crystal size (mm) 0.59 × 0.32 × 0.26
 
Data collection
Diffractometer Bruker APEXII CCD
Absorption correction Multi-scan (SADABS; Bruker, 2013[Bruker (2013). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.])
Tmin, Tmax 0.656, 0.980
No. of measured, independent and observed [I > 2σ(I)] reflections 15463, 3370, 2796
Rint 0.054
(sin θ/λ)max−1) 0.634
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.109, 1.08
No. of reflections 3370
No. of parameters 208
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.45, −0.49
Computer programs: APEX2 and SAINT (Bruker, 2013[Bruker (2013). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), olex2.solve (Bourhis et al., 2015[Bourhis, L. J., Dolomanov, O. V., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2015). Acta Cryst. A71, 59-75.]), SHELXL2014 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]), OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]), SHELXL2014 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), enCIFer (Allen et al., 2004[Allen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst. 37, 335-338.]) and publCIF (Westrip (2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Structural data


Computing details top

Data collection: APEX2 (Bruker, 2013); cell refinement: SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: olex2.solve (Bourhis et al., 2015); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009), SHELXL2014 (Sheldrick, 2015), enCIFer (Allen et al., 2004) and publCIF (Westrip (2010).

3-(2-Chloropyridin-3-yl)quinazoline-2,4(1H,3H)-dione chloroform monosolvate top
Crystal data top
C13H8ClN3O2·CHCl3F(000) = 792
Mr = 393.04Dx = 1.646 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 5.6382 (11) ÅCell parameters from 3659 reflections
b = 13.622 (3) Åθ = 2.5–26.4°
c = 20.662 (4) ŵ = 0.76 mm1
β = 92.289 (6)°T = 100 K
V = 1585.7 (5) Å3Block, colourless
Z = 40.59 × 0.32 × 0.26 mm
Data collection top
Bruker APEXII CCD
diffractometer
2796 reflections with I > 2σ(I)
φ and ω scansRint = 0.054
Absorption correction: multi-scan
(SADABS; Bruker, 2013)
θmax = 26.8°, θmin = 1.8°
Tmin = 0.656, Tmax = 0.980h = 77
15463 measured reflectionsk = 1716
3370 independent reflectionsl = 2626
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) + (0.0529P)2 + 0.6894P]
where P = (Fo2 + 2Fc2)/3
3370 reflections(Δ/σ)max = 0.001
208 parametersΔρmax = 0.45 e Å3
0 restraintsΔρmin = 0.49 e Å3
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl10.12965 (11)0.78921 (4)0.58061 (3)0.02149 (16)
Cl20.36470 (11)0.13451 (5)0.50999 (3)0.02813 (17)
Cl30.40964 (14)0.12297 (5)0.64924 (3)0.03261 (19)
Cl40.03576 (12)0.07201 (5)0.58295 (4)0.03620 (19)
O20.1523 (3)0.60895 (12)0.73418 (7)0.0176 (4)
O10.5724 (3)0.60283 (12)0.55085 (8)0.0213 (4)
N20.3498 (3)0.60913 (13)0.64027 (9)0.0136 (4)
N10.4692 (4)0.87525 (14)0.64811 (9)0.0186 (4)
N30.2842 (4)0.48850 (14)0.56200 (9)0.0172 (4)
H30.32040.46030.52540.021*
C100.2711 (4)0.36988 (17)0.66329 (12)0.0217 (5)
H100.39890.34270.68590.026*
C110.1409 (4)0.44692 (16)0.69008 (11)0.0172 (5)
H110.17810.47240.73130.021*
C50.6601 (4)0.87655 (17)0.68915 (11)0.0191 (5)
H50.73060.93810.69970.023*
C60.4117 (4)0.56808 (16)0.58157 (10)0.0158 (5)
C40.7592 (4)0.79289 (17)0.71677 (11)0.0186 (5)
H40.89320.79680.74600.022*
C120.0464 (4)0.48717 (16)0.65602 (10)0.0139 (4)
C90.2150 (4)0.33221 (17)0.60333 (12)0.0226 (5)
H90.30590.27950.58530.027*
C30.6576 (4)0.70314 (16)0.70056 (11)0.0168 (5)
H3A0.72190.64410.71840.020*
C80.0304 (5)0.36989 (17)0.56961 (12)0.0209 (5)
H80.00800.34280.52900.025*
C70.1001 (4)0.44849 (16)0.59596 (11)0.0156 (5)
C130.1806 (4)0.57113 (16)0.68188 (10)0.0137 (4)
C20.4630 (4)0.70030 (16)0.65844 (10)0.0135 (4)
C10.3755 (4)0.78838 (16)0.63368 (10)0.0154 (5)
C140.2739 (4)0.07115 (17)0.57913 (11)0.0181 (5)
H140.32740.00140.57590.022*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0248 (3)0.0162 (3)0.0229 (3)0.0005 (2)0.0065 (2)0.0010 (2)
Cl20.0266 (3)0.0344 (4)0.0234 (3)0.0062 (3)0.0005 (2)0.0095 (2)
Cl30.0510 (5)0.0250 (3)0.0219 (3)0.0152 (3)0.0019 (3)0.0036 (2)
Cl40.0211 (3)0.0288 (4)0.0594 (5)0.0018 (3)0.0103 (3)0.0094 (3)
O20.0216 (9)0.0148 (8)0.0166 (8)0.0002 (7)0.0025 (6)0.0021 (6)
O10.0281 (10)0.0146 (8)0.0218 (9)0.0078 (7)0.0100 (7)0.0063 (6)
N20.0179 (10)0.0071 (9)0.0159 (9)0.0027 (7)0.0020 (7)0.0021 (7)
N10.0277 (11)0.0089 (9)0.0191 (10)0.0023 (8)0.0004 (8)0.0001 (7)
N30.0237 (11)0.0113 (9)0.0168 (9)0.0052 (8)0.0040 (8)0.0045 (7)
C100.0199 (13)0.0121 (12)0.0331 (14)0.0036 (10)0.0026 (10)0.0036 (9)
C110.0175 (12)0.0120 (11)0.0222 (12)0.0021 (9)0.0019 (9)0.0026 (9)
C50.0266 (13)0.0110 (11)0.0197 (12)0.0048 (10)0.0023 (9)0.0029 (8)
C60.0203 (12)0.0096 (11)0.0175 (11)0.0009 (9)0.0018 (9)0.0006 (8)
C40.0192 (12)0.0172 (12)0.0194 (12)0.0025 (10)0.0010 (9)0.0026 (9)
C120.0153 (11)0.0074 (10)0.0189 (11)0.0017 (9)0.0008 (8)0.0022 (8)
C90.0228 (13)0.0104 (11)0.0344 (14)0.0053 (10)0.0006 (10)0.0018 (10)
C30.0206 (12)0.0111 (11)0.0190 (11)0.0020 (9)0.0035 (9)0.0009 (8)
C80.0274 (13)0.0115 (11)0.0239 (12)0.0021 (10)0.0010 (10)0.0032 (9)
C70.0183 (12)0.0081 (10)0.0203 (11)0.0006 (9)0.0003 (9)0.0014 (8)
C130.0150 (11)0.0098 (10)0.0165 (11)0.0043 (9)0.0009 (8)0.0021 (8)
C20.0172 (11)0.0089 (10)0.0148 (10)0.0018 (9)0.0053 (8)0.0020 (8)
C10.0197 (12)0.0113 (11)0.0152 (11)0.0011 (9)0.0009 (8)0.0004 (8)
C140.0210 (12)0.0113 (11)0.0221 (12)0.0012 (10)0.0024 (9)0.0004 (9)
Geometric parameters (Å, º) top
Cl1—C11.733 (2)C11—H110.9500
Cl2—C141.763 (2)C11—C121.404 (3)
Cl3—C141.759 (2)C5—H50.9500
Cl4—C141.751 (2)C5—C41.383 (3)
O2—C131.214 (3)C4—H40.9500
O1—C61.222 (3)C4—C31.385 (3)
N2—C61.393 (3)C12—C71.392 (3)
N2—C131.408 (3)C12—C131.461 (3)
N2—C21.439 (3)C9—H90.9500
N1—C51.343 (3)C9—C81.375 (4)
N1—C11.325 (3)C3—H3A0.9500
N3—H30.8800C3—C21.373 (3)
N3—C61.354 (3)C8—H80.9500
N3—C71.387 (3)C8—C71.397 (3)
C10—H100.9500C2—C11.387 (3)
C10—C111.383 (3)C14—H141.0000
C10—C91.389 (3)
C6—N2—C13125.71 (19)C8—C9—C10121.2 (2)
C6—N2—C2116.71 (18)C8—C9—H9119.4
C13—N2—C2117.53 (18)C4—C3—H3A120.3
C1—N1—C5117.1 (2)C2—C3—C4119.3 (2)
C6—N3—H3117.9C2—C3—H3A120.3
C6—N3—C7124.24 (19)C9—C8—H8120.5
C7—N3—H3117.9C9—C8—C7119.1 (2)
C11—C10—H10120.0C7—C8—H8120.5
C11—C10—C9120.1 (2)N3—C7—C12119.7 (2)
C9—C10—H10120.0N3—C7—C8119.8 (2)
C10—C11—H11120.2C12—C7—C8120.5 (2)
C10—C11—C12119.6 (2)O2—C13—N2120.3 (2)
C12—C11—H11120.2O2—C13—C12125.0 (2)
N1—C5—H5118.3N2—C13—C12114.72 (18)
N1—C5—C4123.4 (2)C3—C2—N2121.6 (2)
C4—C5—H5118.3C3—C2—C1118.2 (2)
O1—C6—N2120.9 (2)C1—C2—N2120.2 (2)
O1—C6—N3123.4 (2)N1—C1—Cl1115.99 (17)
N3—C6—N2115.66 (19)N1—C1—C2123.8 (2)
C5—C4—H4120.9C2—C1—Cl1120.18 (17)
C5—C4—C3118.1 (2)Cl2—C14—H14108.3
C3—C4—H4120.9Cl3—C14—Cl2109.87 (12)
C11—C12—C13120.8 (2)Cl3—C14—H14108.3
C7—C12—C11119.6 (2)Cl4—C14—Cl2110.84 (13)
C7—C12—C13119.6 (2)Cl4—C14—Cl3111.24 (13)
C10—C9—H9119.4Cl4—C14—H14108.3
N2—C2—C1—Cl10.1 (3)C4—C3—C2—C10.0 (3)
N2—C2—C1—N1179.9 (2)C9—C10—C11—C120.6 (4)
N1—C5—C4—C30.8 (4)C9—C8—C7—N3178.8 (2)
C10—C11—C12—C70.5 (3)C9—C8—C7—C121.0 (4)
C10—C11—C12—C13177.5 (2)C3—C2—C1—Cl1179.73 (17)
C10—C9—C8—C71.0 (4)C3—C2—C1—N10.2 (3)
C11—C10—C9—C80.2 (4)C7—N3—C6—O1179.5 (2)
C11—C12—C7—N3179.6 (2)C7—N3—C6—N20.9 (3)
C11—C12—C7—C80.3 (3)C7—C12—C13—O2178.2 (2)
C11—C12—C13—O23.9 (3)C7—C12—C13—N23.1 (3)
C11—C12—C13—N2174.84 (19)C13—N2—C6—O1175.0 (2)
C5—N1—C1—Cl1179.98 (17)C13—N2—C6—N34.6 (3)
C5—N1—C1—C20.1 (3)C13—N2—C2—C384.3 (3)
C5—C4—C3—C20.5 (3)C13—N2—C2—C195.3 (2)
C6—N2—C13—O2174.7 (2)C13—C12—C7—N31.6 (3)
C6—N2—C13—C126.5 (3)C13—C12—C7—C8178.3 (2)
C6—N2—C2—C398.0 (3)C2—N2—C6—O17.4 (3)
C6—N2—C2—C182.4 (3)C2—N2—C6—N3172.91 (19)
C6—N3—C7—C123.9 (3)C2—N2—C13—O27.8 (3)
C6—N3—C7—C8176.0 (2)C2—N2—C13—C12171.01 (19)
C4—C3—C2—N2179.6 (2)C1—N1—C5—C40.6 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3···O1i0.881.912.791 (3)175
C14—H14···N1ii1.002.393.200 (3)137
C3—H3A···O2iii0.952.483.123 (3)125
Symmetry codes: (i) x+1, y+1, z+1; (ii) x, y1, z; (iii) x+1, y, z.
 

Acknowledgements

The authors thank Andreas Lorbach and Todd B. Marder (Institute of Inorganic Chemistry, Wuerzburg University) for the data collection and structure solution. We appreciate the financial support provided to NSR by the Deutscher Akademischer Austauschdienst (DAAD).

Funding information

Funding for this research was provided by: Deutscher Akademischer Austauschdienst DAAD.

References

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