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

Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 70| Part 11| November 2014| Pages o1185-o1186

Crystal structure of ethyl 6-(chloro­meth­yl)-4-(4-chloro­phen­yl)-2-oxo-1,2,3,4-tetra­hydro­pyrimidine-5-carboxyl­ate

aDepartment of Physics, Annamalai University, Annamalainagar 608 002, Tamil Nadu, India, bDepartment of Physics & Nano Technology, SRM University, SRM Nagar, Kattankulathur, Kancheepuram District, Chennai 603 203, Tamil Nadu, India, cPG and Research Department of Chemistry, Jamal Mohamed College (Autonomous), Tiruchirappalli, Tamil Nadu 620 020, India, and dPG and Research Dept of Chemistry, Jamal Mohamed College (Autonomous), Tiruchirappalli, Tamil Nadu 620 020, India
*Correspondence e-mail: phdguna@gmail.com

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 16 October 2014; accepted 20 October 2014; online 24 October 2014)

In the title compound, C14H14Cl2N2O3, the chloro­phenyl ring makes a dihedral angle of 87.08 (9)° with the tetra­hydro­pyrimidine ring. There is a short intra­molecular C—H⋯O contact present. In the crystal, mol­ecules are linked via pairs of N—H⋯O hydrogen bonds, forming inversion dimers with an R22(8) ring motif. The dimers are linked via a second pair of N—H⋯O hydrogen bonds, this time enclosing an R44(20) ring motif, forming ribbons along [100]. The ribbons are linked via C—H⋯O hydrogen bonds, forming sheets lying parallel to (001). The terminal ethyl group is disordered over two positions with an occupancy ratio of 0.654 (17):0.346 (17).

1. Related literature

For the many biological activities of di­hydro­pyrimidinone derivatives, see: Atwal et al. (1991[Atwal, K. S., Swanson, B. N., Unger, S. E., Floyd, D. M., Moreland, S., Hedberg, A. & O'Reilly, B. C. (1991). J. Med. Chem. 34, 806-811.]); Jauk et al. (2000[Jauk, B., Pernat, T. & Kappe, C. O. (2000). Molecules, 5, 227-239.]); Kato (1984[Kato, T. (1984). Chem. Abstr. 102, 132067.]); Wipf & Cunningham (1995[Wipf, P. & Cunningham, A. (1995). Tetrahedron Lett. 36, 7819-7822.]); Bedia et al. (2006[Bedia, K. K., Elçin, O., Seda, U., Fatma, K., Nathaly, S., Sevim, R. & Dimoglo, A. (2006). Eur. J. Med. Chem. 41, 1253-1261.]); For related structures, see: Nayak et al. (2009[Nayak, S. K., Venugopala, K. N., Chopra, D., Govender, T., Kruger, H. G., Maguire, G. E. M. & Guru Row, T. N. (2009). Acta Cryst. E65, o2502.]); Yuvaraj et al. (2010[Yuvaraj, H., Sundaramoorthy, S., Velmurugan, D. & Kalkhambkar, R. G. (2010). Acta Cryst. E66, o3325.]);

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C14H14Cl2N2O3

  • Mr = 329.17

  • Triclinic, [P \overline 1]

  • a = 7.4698 (3) Å

  • b = 9.1436 (3) Å

  • c = 12.6085 (4) Å

  • α = 107.147 (2)°

  • β = 99.941 (2)°

  • γ = 105.331 (2)°

  • V = 763.71 (5) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.44 mm−1

  • T = 295 K

  • 0.30 × 0.25 × 0.20 mm

2.2. Data collection

  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS, University of G\"ottingen, Germany.]) Tmin = 0.897, Tmax = 0.917

  • 20157 measured reflections

  • 3945 independent reflections

  • 2911 reflections with I > 2σ(I)

  • Rint = 0.022

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.054

  • wR(F2) = 0.153

  • S = 1.03

  • 3945 reflections

  • 211 parameters

  • 26 restraints

  • H-atom parameters constrained

  • Δρmax = 0.64 e Å−3

  • Δρmin = −0.53 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2A⋯O1i 0.86 2.04 2.885 (2) 166
N1—H1⋯O2ii 0.86 2.23 3.070 (2) 166
C11—H11B⋯O1iii 0.97 2.50 3.069 (3) 117
C11—H11A⋯O2 0.97 2.14 2.814 (3) 126
Symmetry codes: (i) -x+1, -y-1, -z; (ii) x+1, y, z; (iii) x-1, y, z.

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2 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: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97 and PLATON.

Supporting information


Comment top

Dihydropyrimidinones (DHPM) and their derivatives are important on account of their wide range of applications in therapeutic and pharmacology, namely because of their anticarcinogenic (Kato, 1984), antihypertensive (Atwal et al., 1991) and calcium channel modulators (Jauk et al., 2000) activities. These derivatives have also been screened for anti-bacterial (Wipf & Cunningham, 1995), and anti-tuberculosis activity (Bedia et al., 2006).

The geometric parameters of the title molecule (Fig. 1) agree well with those reported fro similar structures (Nayak et al., 2009; Yuvaraj et al., 2010). The chlorophenyl ring makes a dihedral angles of 87.08 (9) ° with the tetrahydropyrimidine ring. There is a short intramolecular C—H···O contact (Table 1).

In the crystal, molecules are linked via a pair of N—H···O hydrogen bonds forming inversion dimers with an R22(8) ring motif. The dimers are linked via a second pair of N—H···O hydrogen bonds, this time enclosing an R44(20) ring motif, forming ribbons along [100]. The ribbons are linked via C—H···O hydrogen bonds forming sheets lying parallel to (001); see Table 1 and Fig. 2 for details.

Related literature top

For the many biological activities of dihydropyrimidinone derivatives, see: Atwal et al. (1991); Jauk et al. (2000); Kato (1984); Wipf & Cunningham (1995); Bedia et al. (2006); For related structures, see: Nayak et al. (2009); Yuvaraj et al. (2010);

Experimental top

A mixture of ethyl-4-chloro acetoacetate (4.1 ml, 0.025 mol), 4-chlorobenzaldehyde (3.6 g, 0.025 mol), and urea (4.5 g, 0.075 mol) in ethanol (5 ml) was heated under reflux in the presence of concentrated HCl (1 mL) for 5 h (monitored by TLC). The reaction mixture, after being cooled to room temperature, was poured onto crushed ice and stirred for 5–10 min. The solid was separated and filtered under suction, washed with ice-cold water (50 ml), and then recrystallized from hot ethanol to afford pure product [m.p. 437 K; yield 76%].

Refinement top

The terminal ethyl group is disordered over two position. The refined site occupancies of the disordered C atoms are C13/C14 = 0.654 (17) and C13A/C14A = 0.346 (17). The O3—C13A and C13A—C14A bond distances was restrained to be 1.400 (1) Å. In the refinement, ISOR was used for atoms C13, C14, C13A and C14A. The H atoms were positioned geometrically and refined using a riding model: N—H = 0.86 Å, C—H = 0.93 - 0.98 Å with Uiso(H) = 1.5Ueq(C) for methyl H atoms and = 1.2Ueq(N,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: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
The molecular structure of the title molecule, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level.

The crystal packing of the title compound, viewed along the a axis. Hydrogen bonds are shown as dashed lines (see Table 1 for details).
Ethyl 6-(chloromethyl)-4-(4-chlorophenyl)-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate top
Crystal data top
C14H14Cl2N2O3Z = 2
Mr = 329.17F(000) = 340
Triclinic, P1Dx = 1.431 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.4698 (3) ÅCell parameters from 4865 reflections
b = 9.1436 (3) Åθ = 2.5–30.1°
c = 12.6085 (4) ŵ = 0.44 mm1
α = 107.147 (2)°T = 295 K
β = 99.941 (2)°Block, colourless
γ = 105.331 (2)°0.30 × 0.25 × 0.20 mm
V = 763.71 (5) Å3
Data collection top
Bruker APEXII CCD
diffractometer
3945 independent reflections
Radiation source: fine-focus sealed tube2911 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.022
Detector resolution: 0 pixels mm-1θmax = 31.0°, θmin = 2.5°
ω and ϕ scansh = 1010
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
k = 1212
Tmin = 0.897, Tmax = 0.917l = 1817
20157 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)] = 0.054Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.153H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0628P)2 + 0.6453P]
where P = (Fo2 + 2Fc2)/3
3945 reflections(Δ/σ)max < 0.001
211 parametersΔρmax = 0.64 e Å3
26 restraintsΔρmin = 0.53 e Å3
Crystal data top
C14H14Cl2N2O3γ = 105.331 (2)°
Mr = 329.17V = 763.71 (5) Å3
Triclinic, P1Z = 2
a = 7.4698 (3) ÅMo Kα radiation
b = 9.1436 (3) ŵ = 0.44 mm1
c = 12.6085 (4) ÅT = 295 K
α = 107.147 (2)°0.30 × 0.25 × 0.20 mm
β = 99.941 (2)°
Data collection top
Bruker APEXII CCD
diffractometer
3945 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2911 reflections with I > 2σ(I)
Tmin = 0.897, Tmax = 0.917Rint = 0.022
20157 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.05426 restraints
wR(F2) = 0.153H-atom parameters constrained
S = 1.03Δρmax = 0.64 e Å3
3945 reflectionsΔρmin = 0.53 e Å3
211 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
C10.8422 (5)0.1384 (4)0.5387 (2)0.0651 (8)
C20.7145 (5)0.0099 (4)0.4712 (3)0.0725 (9)
H20.67120.08780.50310.087*
C30.6488 (4)0.0442 (3)0.3538 (2)0.0598 (7)
H30.55880.14530.30730.072*
C40.7137 (3)0.0674 (3)0.30506 (18)0.0361 (4)
C50.8424 (5)0.2165 (4)0.3761 (3)0.0699 (9)
H50.88760.29500.34520.084*
C60.9060 (6)0.2518 (4)0.4938 (3)0.0895 (12)
H60.99250.35370.54140.107*
C70.6508 (3)0.0279 (2)0.17587 (17)0.0306 (4)
H70.70320.12800.16130.037*
C80.6382 (3)0.2509 (2)0.06968 (18)0.0342 (4)
C90.3408 (3)0.1913 (2)0.06544 (17)0.0315 (4)
C100.4341 (3)0.0329 (2)0.12644 (16)0.0300 (4)
C110.1275 (3)0.2650 (3)0.0111 (2)0.0454 (5)
H11A0.07520.17990.00680.055*
H11B0.06730.31620.05930.055*
C120.3328 (3)0.0848 (3)0.15276 (18)0.0360 (4)
N10.7306 (2)0.0910 (2)0.11509 (15)0.0338 (4)
H10.84500.05550.10810.041*
N20.4415 (2)0.2989 (2)0.05067 (17)0.0375 (4)
H2A0.37810.40090.02850.045*
O10.7187 (2)0.35121 (19)0.04214 (16)0.0488 (4)
O20.1610 (2)0.0561 (2)0.13615 (16)0.0508 (4)
O30.4586 (2)0.23490 (19)0.20251 (17)0.0554 (5)
C130.374 (3)0.3618 (16)0.2478 (12)0.086 (4)0.654 (17)
H13A0.29240.37450.18470.103*0.654 (17)
H13B0.29590.33180.29710.103*0.654 (17)
C140.5303 (12)0.5098 (7)0.3121 (11)0.116 (4)0.654 (17)
H14A0.60810.49640.37520.174*0.654 (17)
H14B0.48030.59550.34150.174*0.654 (17)
H14C0.60760.53710.26270.174*0.654 (17)
C13A0.394 (4)0.368 (3)0.2319 (11)0.070 (7)0.346 (17)
H13C0.25980.33570.19000.084*0.346 (17)
H13D0.46840.45310.20980.084*0.346 (17)
C14A0.414 (4)0.428 (3)0.3506 (12)0.127 (10)0.346 (17)
H14D0.31990.35330.36970.190*0.346 (17)
H14E0.39370.53140.37130.190*0.346 (17)
H14F0.54090.44150.39200.190*0.346 (17)
Cl10.92366 (19)0.18204 (17)0.68608 (7)0.1114 (4)
Cl20.07043 (8)0.41074 (8)0.12863 (5)0.0522 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0719 (18)0.085 (2)0.0334 (12)0.0407 (17)0.0004 (12)0.0089 (13)
C20.095 (2)0.079 (2)0.0475 (16)0.0299 (19)0.0186 (15)0.0296 (15)
C30.0751 (18)0.0529 (15)0.0402 (13)0.0083 (13)0.0088 (12)0.0163 (11)
C40.0315 (10)0.0396 (11)0.0348 (10)0.0151 (8)0.0040 (8)0.0098 (8)
C50.076 (2)0.0498 (15)0.0523 (16)0.0029 (14)0.0110 (14)0.0120 (12)
C60.099 (3)0.069 (2)0.0506 (18)0.0008 (19)0.0216 (17)0.0003 (16)
C70.0246 (9)0.0292 (9)0.0363 (10)0.0085 (7)0.0058 (7)0.0110 (8)
C80.0261 (9)0.0363 (10)0.0398 (10)0.0112 (8)0.0095 (8)0.0122 (8)
C90.0228 (8)0.0364 (10)0.0361 (10)0.0107 (7)0.0095 (7)0.0124 (8)
C100.0255 (9)0.0331 (9)0.0325 (9)0.0112 (7)0.0066 (7)0.0126 (8)
C110.0262 (10)0.0453 (12)0.0516 (13)0.0079 (9)0.0099 (9)0.0027 (10)
C120.0343 (10)0.0374 (10)0.0370 (10)0.0163 (8)0.0061 (8)0.0123 (8)
N10.0207 (7)0.0351 (9)0.0416 (9)0.0079 (6)0.0086 (6)0.0094 (7)
N20.0237 (8)0.0284 (8)0.0552 (11)0.0069 (6)0.0101 (7)0.0096 (7)
O10.0303 (8)0.0385 (8)0.0734 (12)0.0151 (6)0.0150 (7)0.0103 (8)
O20.0333 (8)0.0521 (10)0.0681 (11)0.0229 (7)0.0135 (7)0.0155 (8)
O30.0431 (9)0.0336 (8)0.0738 (12)0.0180 (7)0.0026 (8)0.0034 (8)
C130.071 (6)0.051 (6)0.116 (9)0.039 (4)0.008 (6)0.001 (5)
C140.100 (5)0.041 (3)0.171 (9)0.017 (3)0.030 (5)0.003 (4)
C13A0.077 (14)0.052 (10)0.063 (8)0.048 (10)0.016 (7)0.009 (7)
C14A0.18 (2)0.138 (18)0.075 (9)0.115 (18)0.028 (9)0.000 (9)
Cl10.1383 (10)0.1531 (11)0.0355 (4)0.0742 (8)0.0001 (5)0.0144 (5)
Cl20.0426 (3)0.0510 (4)0.0510 (3)0.0153 (3)0.0023 (2)0.0100 (3)
Geometric parameters (Å, º) top
C1—C61.342 (5)C11—Cl21.766 (2)
C1—C21.352 (5)C11—H11A0.9700
C1—Cl11.739 (3)C11—H11B0.9700
C2—C31.388 (4)C12—O21.207 (3)
C2—H20.9300C12—O31.330 (3)
C3—C41.366 (3)N1—H10.8600
C3—H30.9300N2—H2A0.8600
C4—C51.369 (3)O3—C13A1.4000 (10)
C4—C71.518 (3)O3—C131.482 (8)
C5—C61.387 (4)C13—C141.430 (19)
C5—H50.9300C13—H13A0.9700
C6—H60.9300C13—H13B0.9700
C7—N11.461 (2)C14—H14A0.9600
C7—C101.513 (2)C14—H14B0.9600
C7—H70.9800C14—H14C0.9600
C8—O11.225 (2)C13A—C14A1.4000 (10)
C8—N11.333 (3)C13A—H13C0.9700
C8—N21.373 (2)C13A—H13D0.9700
C9—C101.341 (3)C14A—H14D0.9600
C9—N21.379 (2)C14A—H14E0.9600
C9—C111.498 (3)C14A—H14F0.9600
C10—C121.466 (3)
C6—C1—C2121.0 (3)Cl2—C11—H11A109.2
C6—C1—Cl1119.8 (3)C9—C11—H11B109.2
C2—C1—Cl1119.2 (3)Cl2—C11—H11B109.2
C1—C2—C3119.1 (3)H11A—C11—H11B107.9
C1—C2—H2120.5O2—C12—O3122.43 (19)
C3—C2—H2120.5O2—C12—C10127.3 (2)
C4—C3—C2121.3 (3)O3—C12—C10110.28 (17)
C4—C3—H3119.4C8—N1—C7124.46 (16)
C2—C3—H3119.4C8—N1—H1117.8
C3—C4—C5118.0 (2)C7—N1—H1117.8
C3—C4—C7121.6 (2)C8—N2—C9123.10 (17)
C5—C4—C7120.4 (2)C8—N2—H2A118.5
C4—C5—C6120.8 (3)C9—N2—H2A118.4
C4—C5—H5119.6C12—O3—C13A120.4 (14)
C6—C5—H5119.6C12—O3—C13114.8 (8)
C1—C6—C5119.8 (3)C13A—O3—C1310.8 (18)
C1—C6—H6120.1C14—C13—O3107.3 (12)
C5—C6—H6120.1C14—C13—H13A110.3
N1—C7—C10109.45 (15)O3—C13—H13A110.3
N1—C7—C4110.73 (15)C14—C13—H13B110.3
C10—C7—C4113.47 (16)O3—C13—H13B110.3
N1—C7—H7107.7H13A—C13—H13B108.5
C10—C7—H7107.7O3—C13A—C14A110.7 (9)
C4—C7—H7107.7O3—C13A—H13C109.5
O1—C8—N1123.56 (18)C14A—C13A—H13C109.5
O1—C8—N2120.66 (19)O3—C13A—H13D109.5
N1—C8—N2115.73 (17)C14A—C13A—H13D109.5
C10—C9—N2120.01 (17)H13C—C13A—H13D108.1
C10—C9—C11124.57 (18)C13A—C14A—H14D109.5
N2—C9—C11115.41 (18)C13A—C14A—H14E109.5
C9—C10—C12122.35 (17)H14D—C14A—H14E109.5
C9—C10—C7119.80 (17)C13A—C14A—H14F109.5
C12—C10—C7117.78 (17)H14D—C14A—H14F109.5
C9—C11—Cl2112.02 (15)H14E—C14A—H14F109.5
C9—C11—H11A109.2
C6—C1—C2—C30.1 (5)C10—C9—C11—Cl2138.10 (19)
Cl1—C1—C2—C3179.6 (3)N2—C9—C11—Cl242.8 (3)
C1—C2—C3—C41.4 (5)C9—C10—C12—O28.7 (4)
C2—C3—C4—C51.7 (5)C7—C10—C12—O2168.2 (2)
C2—C3—C4—C7176.7 (3)C9—C10—C12—O3173.0 (2)
C3—C4—C5—C60.7 (5)C7—C10—C12—O310.1 (3)
C7—C4—C5—C6177.7 (3)O1—C8—N1—C7163.2 (2)
C2—C1—C6—C50.8 (6)N2—C8—N1—C719.2 (3)
Cl1—C1—C6—C5179.4 (3)C10—C7—N1—C831.1 (3)
C4—C5—C6—C10.5 (6)C4—C7—N1—C894.8 (2)
C3—C4—C7—N168.6 (3)O1—C8—N2—C9171.1 (2)
C5—C4—C7—N1109.8 (3)N1—C8—N2—C96.6 (3)
C3—C4—C7—C1055.0 (3)C10—C9—N2—C816.8 (3)
C5—C4—C7—C10126.6 (3)C11—C9—N2—C8164.1 (2)
N2—C9—C10—C12174.98 (18)O2—C12—O3—C13A3.8 (9)
C11—C9—C10—C124.0 (3)C10—C12—O3—C13A177.8 (9)
N2—C9—C10—C71.8 (3)O2—C12—O3—C136.6 (7)
C11—C9—C10—C7179.16 (19)C10—C12—O3—C13171.8 (7)
N1—C7—C10—C919.3 (3)C12—O3—C13—C14171.9 (10)
C4—C7—C10—C9105.0 (2)C13A—O3—C13—C1465 (9)
N1—C7—C10—C12163.80 (17)C12—O3—C13A—C14A103 (2)
C4—C7—C10—C1272.0 (2)C13—O3—C13A—C14A42 (7)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···O1i0.862.042.885 (2)166
N1—H1···O2ii0.862.233.070 (2)166
C11—H11B···O1iii0.972.503.069 (3)117
C11—H11A···O20.972.142.814 (3)126
Symmetry codes: (i) x+1, y1, z; (ii) x+1, y, z; (iii) x1, y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···O1i0.862.042.885 (2)166
N1—H1···O2ii0.862.233.070 (2)166
C11—H11B···O1iii0.972.503.069 (3)117
C11—H11A···O20.972.142.814 (3)126
Symmetry codes: (i) x+1, y1, z; (ii) x+1, y, z; (iii) x1, y, z.
 

Acknowledgements

SB thanks Professor K. Ramamurthi, Department of Physics and Nanotechnology, SRM University, Chennai, for his guidance and valuable suggestions.

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Volume 70| Part 11| November 2014| Pages o1185-o1186
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