4-(4-Bromo­phen­yl)-5-oxo-1,2,3,4,5,6,7,8-octa­hydro­quinazoline-2-thione

Xie, M.; Deng, C.; Zheng, J.; Zhu, Y.

doi:10.1107/S1600536809028761

organic compounds

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ISSN: 2056-9890

Volume 65| Part 8| August 2009| Page o1980

doi:10.1107/S1600536809028761

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4-(4-Bromophenyl)-5-oxo-1,2,3,4,5,6,7,8-octahydroquinazoline-2-thione

Min Xie,^a Changquan Deng,^a Jie Zheng ^a and Yulin Zhu ^a ^*

^aSchool of Chemistry and Environment, South China Normal University, Guangzhou 510006, People's Republic of China
^*Correspondence e-mail: yulinzhu2002@yahoo.com.cn

(Received 22 June 2009; accepted 21 July 2009; online 25 July 2009)

The title compound, C₁₄H₁₃BrN₂OS, was synthesized from the multicomponent reaction between thiourea, 4-bromobenzaldehyde and cyclohexane-1,3-dione. The crystal packing is stabilized by intermolecular N—H⋯O, N—H⋯S, C—H⋯O and C—H⋯S hydrogen bonds. Br⋯O interactions [3.183 (3) Å] are also observed in the crystal structure.

Related literature

For the pharmaceutical applications of 4-aryl-5-oxo-1,2,3,4,5,6,7,8-octahydroquinazoline-2-thiones, see: Kappe & Stadler (2004 ); Sarac et al. (1997 , 1999 ); Yarima et al., (2003 ). For background information on halogen bonding, see: Damodharana et al. (2004 ); Sureshan et al. (2001 ); Yang et al. (2008 ).

Experimental

Crystal data

C₁₄H₁₃BrN₂OS
M_r = 337.23
Triclinic, $[P \overline 1]$
a = 7.0395 (11) Å
b = 8.1859 (13) Å
c = 13.286 (2) Å
α = 105.329 (2)°
β = 91.279 (2)°
γ = 103.854 (2)°
V = 713.9 (2) Å³
Z = 2
Mo Kα radiation
μ = 3.02 mm⁻¹
T = 293 K
0.25 × 0.25 × 0.20 mm

Data collection

Bruker APEXII area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2004 ) T_min = 0.429, T_max = 0.547
3953 measured reflections
2744 independent reflections
1880 reflections with I > 2σ(I)
R_int = 0.021

Refinement

R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.117
S = 1.04
2744 reflections
174 parameters
H-atom parameters constrained
Δρ_max = 0.42 e Å⁻³
Δρ_min = −0.60 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2A⋯S1ⁱ	0.97	2.98	3.781 (4)	140
N2—H2⋯S1ⁱⁱ	0.86	2.55	3.380 (3)	161
N1—H1⋯O1ⁱⁱⁱ	0.86	2.00	2.832 (4)	164
C4—H4A⋯O1ⁱⁱⁱ	0.97	2.59	3.361 (4)	137
Symmetry codes: (i) -x+1, -y+2, -z+1; (ii) -x+1, -y+1, -z+1; (iii) x+1, y, z.

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; 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.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809028761/zl2225sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809028761/zl2225Isup2.hkl

checkCIF report

Comment top

4-Aryl-5-oxo-1,2,3,4,5,6,7,8-octahydroquinazoline-2-thiones have received much attention recently because of their pharmaceutical applications. (Kappe & Stadler, 2004; Sarac et al., 1997; Sarac et al., 1999). For example, the calcium antagonist activity of the compounds was tested in vitro on isolated rat ileum and lamb carotid artery. (Yarima et al., 2003). As part of our on going studies on the synthesis of quinazolinethiones, the title compound was isolated under Biginelli reaction conditions (Figure 1).

The reaction between thiourea, 4-bromobenzaldehyde, and 1,3-cyclohexanedione instead of an open-chain dicarbonyl compound in the presence of palladium(II) 2,4-pentanedionate as catalyst proceeded to give the title compound in excellent yield. A representation of the title compound is given in Figure 2. There are no unusual bond lengths and angles in the compound. The molecules in the structure are linked via N1—H1···O1 and paired N2—H2···S1 intermolecular hydrogen bonds. The bromine atom Br1 exhibits a Br···O halogen bond with oxygen atom O1 (Figure 3). (Damodharana et al., 2004; Sureshan et al., 2001; Yang et al., 2008). The Br1···O1 distance of this interaction is 3.182 Å, which is less than the sum of their van der Waals radii.

Related literature top

For the pharmaceutical applications of 4-aryl-5-oxo-1,2,3,4,5,6,7,8-octahydroquinazoline-2-thiones, see: Kappe & Stadler (2004); Sarac et al. (1997, 1999); Yarima et al., (2003). For backround information on halogen bonding, see: Damodharana et al. (2004); Sureshan et al. (2001); Yang et al. (2008).

Experimental top

A mixture of thiourea (0.91 g, 12 mmol), 4-bromobenzaldehyde (1.84 g, 10 mmol), 1,3-cyclohexanedione (1.12 g, 10 mmol), and palladium(II) 2,4-pentanedionate (0.0020 mg) was refluxed in acetonitrile (12 ml) at 353 K for 4 h. After being cooled to room temperature, the reaction mixture was poured into water. The white precipitate was filtered off with a silica pad, washed twice with water, and the filtrate was then dried under vacuum to yield the product. Single crystals of the title compound were obtained by slow evaporation from ethanol at room temperature to yield colourless, block-shaped crystal.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); 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

	Fig. 1. Palladium(II) 2,4-pentanedionate catalyzed synthesis of the title compound.
	Fig. 2. View of the title compound showing the atom-labelling scheme. Ellipsoids are drawn at the 50% probability level.
	Fig. 3. Perspective view of the packing of the title compound. Dashed lines stand for N1—H1···O1 and N2—H2···S1 intermolecular hydrogen bonds and Br1···O1 interactions.

4-(4-Bromophenyl)-5-oxo-1,2,3,4,5,6,7,8-octahydroquinazoline-2-thione top

Crystal data top

C₁₄H₁₃BrN₂OS	Z = 2
M_r = 337.23	F(000) = 340
Triclinic, P1	D_x = 1.569 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.0395 (11) Å	Cell parameters from 1089 reflections
b = 8.1859 (13) Å	θ = 2.7–23.6°
c = 13.286 (2) Å	µ = 3.02 mm⁻¹
α = 105.329 (2)°	T = 293 K
β = 91.279 (2)°	Block, colourless
γ = 103.854 (2)°	0.25 × 0.25 × 0.20 mm
V = 713.9 (2) Å³

Data collection top

Bruker APEXII area-detector diffractometer	2744 independent reflections
Radiation source: fine-focus sealed tube	1880 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.021
ϕ and ω scans	θ_max = 26.0°, θ_min = 1.6°
Absorption correction: multi-scan (APEX2; Bruker, 2004)	h = −8→8
T_min = 0.429, T_max = 0.547	k = −10→10
3953 measured reflections	l = −16→16

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.046	H-atom parameters constrained
wR(F²) = 0.117	w = 1/[σ²(F_o²) + (0.0382P)² + 0.8552P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max < 0.001
2744 reflections	Δρ_max = 0.42 e Å⁻³
174 parameters	Δρ_min = −0.60 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0058 (17)

Crystal data top

C₁₄H₁₃BrN₂OS	γ = 103.854 (2)°
M_r = 337.23	V = 713.9 (2) Å³
Triclinic, P1	Z = 2
a = 7.0395 (11) Å	Mo Kα radiation
b = 8.1859 (13) Å	µ = 3.02 mm⁻¹
c = 13.286 (2) Å	T = 293 K
α = 105.329 (2)°	0.25 × 0.25 × 0.20 mm
β = 91.279 (2)°

Data collection top

Bruker APEXII area-detector diffractometer	2744 independent reflections
Absorption correction: multi-scan (APEX2; Bruker, 2004)	1880 reflections with I > 2σ(I)
T_min = 0.429, T_max = 0.547	R_int = 0.021
3953 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	0 restraints
wR(F²) = 0.117	H-atom parameters constrained
S = 1.04	Δρ_max = 0.42 e Å⁻³
2744 reflections	Δρ_min = −0.60 e Å⁻³
174 parameters

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.

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

	x	y	z	U_iso*/U_eq
Br1	0.08077 (11)	0.17375 (8)	−0.08352 (4)	0.0927 (3)
S1	0.81565 (14)	0.62120 (13)	0.47136 (8)	0.0395 (3)
N2	0.4706 (4)	0.6637 (4)	0.4168 (2)	0.0322 (7)
H2	0.4223	0.6000	0.4568	0.039*
C8	0.6646 (5)	0.7134 (5)	0.4188 (3)	0.0294 (8)
C7	0.3316 (5)	0.7096 (4)	0.3511 (3)	0.0291 (8)
H7	0.2139	0.7176	0.3881	0.035*
C6	0.4253 (5)	0.8861 (4)	0.3369 (3)	0.0282 (8)
C5	0.6241 (5)	0.9449 (4)	0.3455 (3)	0.0287 (8)
C1	0.3007 (5)	0.9915 (4)	0.3130 (3)	0.0303 (8)
C4	0.7274 (5)	1.1109 (5)	0.3220 (3)	0.0352 (9)
H4A	0.8475	1.0964	0.2906	0.042*
H4B	0.7626	1.2047	0.3867	0.042*
C2	0.3965 (5)	1.1566 (5)	0.2867 (3)	0.0396 (9)
H2A	0.4084	1.2547	0.3484	0.047*
H2B	0.3129	1.1722	0.2328	0.047*
C3	0.5987 (5)	1.1589 (5)	0.2486 (3)	0.0402 (9)
H3A	0.5851	1.0768	0.1796	0.048*
H3B	0.6606	1.2749	0.2426	0.048*
N1	0.7383 (4)	0.8485 (4)	0.3772 (2)	0.0350 (7)
H1	0.8622	0.8751	0.3703	0.042*
C9	0.2714 (5)	0.5708 (4)	0.2475 (3)	0.0321 (8)
C12	0.1586 (8)	0.3298 (5)	0.0523 (3)	0.0557 (12)
C14	0.0763 (6)	0.4943 (6)	0.2134 (4)	0.0598 (13)
H14	−0.0197	0.5240	0.2564	0.072*
C10	0.4095 (6)	0.5213 (6)	0.1814 (3)	0.0482 (11)
H10	0.5424	0.5704	0.2027	0.058*
C11	0.3538 (7)	0.4003 (6)	0.0842 (3)	0.0545 (12)
H11	0.4483	0.3674	0.0411	0.065*
C13	0.0205 (8)	0.3738 (7)	0.1163 (4)	0.0802 (18)
H13	−0.1120	0.3228	0.0947	0.096*
O1	0.1229 (4)	0.9472 (3)	0.3167 (2)	0.0426 (7)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.1179 (6)	0.0830 (5)	0.0453 (3)	−0.0032 (4)	0.0010 (3)	−0.0098 (3)
S1	0.0319 (6)	0.0473 (6)	0.0477 (6)	0.0135 (4)	0.0060 (4)	0.0239 (5)
N2	0.0243 (17)	0.0368 (17)	0.0377 (17)	0.0038 (13)	0.0046 (13)	0.0172 (14)
C8	0.027 (2)	0.036 (2)	0.0277 (18)	0.0093 (16)	0.0019 (14)	0.0123 (15)
C7	0.0207 (18)	0.0322 (19)	0.0358 (19)	0.0052 (15)	0.0042 (15)	0.0127 (15)
C6	0.0252 (19)	0.0285 (18)	0.0306 (18)	0.0044 (15)	0.0049 (14)	0.0099 (14)
C5	0.0245 (19)	0.0284 (18)	0.0348 (19)	0.0065 (15)	0.0069 (15)	0.0114 (15)
C1	0.026 (2)	0.0326 (19)	0.0319 (19)	0.0073 (15)	0.0046 (15)	0.0079 (15)
C4	0.026 (2)	0.031 (2)	0.050 (2)	0.0026 (16)	0.0055 (17)	0.0165 (17)
C2	0.030 (2)	0.039 (2)	0.053 (2)	0.0100 (17)	0.0058 (18)	0.0179 (18)
C3	0.034 (2)	0.041 (2)	0.051 (2)	0.0052 (18)	0.0070 (18)	0.0251 (19)
N1	0.0208 (16)	0.0410 (18)	0.0496 (19)	0.0077 (13)	0.0072 (14)	0.0231 (15)
C9	0.030 (2)	0.0297 (19)	0.038 (2)	0.0042 (16)	0.0037 (16)	0.0161 (16)
C12	0.073 (3)	0.040 (2)	0.041 (2)	−0.003 (2)	0.007 (2)	0.0044 (19)
C14	0.034 (2)	0.074 (3)	0.050 (3)	−0.002 (2)	0.006 (2)	−0.003 (2)
C10	0.037 (2)	0.054 (3)	0.049 (3)	0.010 (2)	0.0076 (19)	0.008 (2)
C11	0.067 (3)	0.051 (3)	0.044 (3)	0.014 (2)	0.015 (2)	0.010 (2)
C13	0.045 (3)	0.092 (4)	0.064 (3)	−0.013 (3)	0.000 (3)	−0.017 (3)
O1	0.0251 (15)	0.0507 (17)	0.0573 (18)	0.0117 (12)	0.0069 (12)	0.0221 (14)

Geometric parameters (Å, º) top

Br1—C12	1.895 (4)	C4—H4B	0.9700
Br1—O1ⁱ	3.183 (3)	C2—C3	1.519 (5)
S1—C8	1.678 (4)	C2—H2A	0.9700
N2—C8	1.326 (4)	C2—H2B	0.9700
N2—C7	1.474 (4)	C3—H3A	0.9700
N2—H2	0.8600	C3—H3B	0.9700
C8—N1	1.364 (4)	N1—H1	0.8600
C7—C6	1.500 (5)	C9—C14	1.376 (5)
C7—C9	1.510 (5)	C9—C10	1.386 (5)
C7—H7	0.9800	C12—C13	1.356 (6)
C6—C5	1.358 (5)	C12—C11	1.366 (7)
C6—C1	1.453 (5)	C14—C13	1.383 (6)
C5—N1	1.382 (4)	C14—H14	0.9300
C5—C4	1.495 (5)	C10—C11	1.384 (6)
C1—O1	1.222 (4)	C10—H10	0.9300
C1—C2	1.492 (5)	C11—H11	0.9300
C4—C3	1.504 (5)	C13—H13	0.9300
C4—H4A	0.9700

C12—Br1—O1ⁱ	154.81 (16)	C1—C2—H2B	108.9
C8—N2—C7	124.8 (3)	C3—C2—H2B	108.9
C8—N2—H2	117.6	H2A—C2—H2B	107.7
C7—N2—H2	117.6	C4—C3—C2	111.6 (3)
N2—C8—N1	116.3 (3)	C4—C3—H3A	109.3
N2—C8—S1	123.1 (3)	C2—C3—H3A	109.3
N1—C8—S1	120.6 (3)	C4—C3—H3B	109.3
N2—C7—C6	108.5 (3)	C2—C3—H3B	109.3
N2—C7—C9	111.0 (3)	H3A—C3—H3B	108.0
C6—C7—C9	112.0 (3)	C8—N1—C5	123.3 (3)
N2—C7—H7	108.4	C8—N1—H1	118.3
C6—C7—H7	108.4	C5—N1—H1	118.3
C9—C7—H7	108.4	C14—C9—C10	117.5 (4)
C5—C6—C1	120.8 (3)	C14—C9—C7	121.0 (3)
C5—C6—C7	120.1 (3)	C10—C9—C7	121.4 (3)
C1—C6—C7	119.1 (3)	C13—C12—C11	120.5 (4)
C6—C5—N1	119.4 (3)	C13—C12—Br1	119.9 (4)
C6—C5—C4	122.9 (3)	C11—C12—Br1	119.6 (3)
N1—C5—C4	117.7 (3)	C9—C14—C13	121.1 (4)
O1—C1—C6	120.6 (3)	C9—C14—H14	119.4
O1—C1—C2	121.3 (3)	C13—C14—H14	119.4
C6—C1—C2	118.1 (3)	C11—C10—C9	121.4 (4)
C5—C4—C3	110.8 (3)	C11—C10—H10	119.3
C5—C4—H4A	109.5	C9—C10—H10	119.3
C3—C4—H4A	109.5	C12—C11—C10	119.3 (4)
C5—C4—H4B	109.5	C12—C11—H11	120.3
C3—C4—H4B	109.5	C10—C11—H11	120.3
H4A—C4—H4B	108.1	C12—C13—C14	120.2 (5)
C1—C2—C3	113.4 (3)	C12—C13—H13	119.9
C1—C2—H2A	108.9	C14—C13—H13	119.9
C3—C2—H2A	108.9

C7—N2—C8—N1	16.5 (5)	C1—C2—C3—C4	−50.8 (5)
C7—N2—C8—S1	−164.9 (3)	N2—C8—N1—C5	7.6 (5)
C8—N2—C7—C6	−31.3 (4)	S1—C8—N1—C5	−171.1 (3)
C8—N2—C7—C9	92.1 (4)	C6—C5—N1—C8	−12.3 (5)
N2—C7—C6—C5	24.8 (4)	C4—C5—N1—C8	167.8 (3)
C9—C7—C6—C5	−98.0 (4)	N2—C7—C9—C14	126.7 (4)
N2—C7—C6—C1	−155.8 (3)	C6—C7—C9—C14	−111.9 (4)
C9—C7—C6—C1	81.3 (4)	N2—C7—C9—C10	−56.1 (4)
C1—C6—C5—N1	174.5 (3)	C6—C7—C9—C10	65.3 (4)
C7—C6—C5—N1	−6.1 (5)	O1ⁱ—Br1—C12—C13	63.0 (6)
C1—C6—C5—C4	−5.6 (5)	O1ⁱ—Br1—C12—C11	−115.5 (5)
C7—C6—C5—C4	173.8 (3)	C10—C9—C14—C13	−0.7 (7)
C5—C6—C1—O1	−171.9 (3)	C7—C9—C14—C13	176.6 (5)
C7—C6—C1—O1	8.8 (5)	C14—C9—C10—C11	0.5 (6)
C5—C6—C1—C2	6.5 (5)	C7—C9—C10—C11	−176.8 (4)
C7—C6—C1—C2	−172.9 (3)	C13—C12—C11—C10	−1.9 (7)
C6—C5—C4—C3	−23.7 (5)	Br1—C12—C11—C10	176.6 (3)
N1—C5—C4—C3	156.2 (3)	C9—C10—C11—C12	0.8 (7)
O1—C1—C2—C3	−159.6 (4)	C11—C12—C13—C14	1.8 (9)
C6—C1—C2—C3	22.0 (5)	Br1—C12—C13—C14	−176.8 (4)
C5—C4—C3—C2	50.7 (4)	C9—C14—C13—C12	−0.4 (9)

Symmetry code: (i) −x, −y+1, −z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2A···S1ⁱⁱ	0.97	2.98	3.781 (4)	140
N2—H2···S1ⁱⁱⁱ	0.86	2.55	3.380 (3)	161
N1—H1···O1^iv	0.86	2.00	2.832 (4)	164
C4—H4A···O1^iv	0.97	2.59	3.361 (4)	137

Symmetry codes: (ii) −x+1, −y+2, −z+1; (iii) −x+1, −y+1, −z+1; (iv) x+1, y, z.

Experimental details

Crystal data
Chemical formula	C₁₄H₁₃BrN₂OS
M_r	337.23
Crystal system, space group	Triclinic, P1
Temperature (K)	293
a, b, c (Å)	7.0395 (11), 8.1859 (13), 13.286 (2)
α, β, γ (°)	105.329 (2), 91.279 (2), 103.854 (2)
V (Å³)	713.9 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	3.02
Crystal size (mm)	0.25 × 0.25 × 0.20

Data collection
Diffractometer	Bruker APEXII area-detector diffractometer
Absorption correction	Multi-scan (APEX2; Bruker, 2004)
T_min, T_max	0.429, 0.547
No. of measured, independent and observed [I > 2σ(I)] reflections	3953, 2744, 1880
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.117, 1.04
No. of reflections	2744
No. of parameters	174
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.42, −0.60

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2A···S1ⁱ	0.97	2.98	3.781 (4)	140.3
N2—H2···S1ⁱⁱ	0.86	2.55	3.380 (3)	161.0
N1—H1···O1ⁱⁱⁱ	0.86	2.00	2.832 (4)	163.7
C4—H4A···O1ⁱⁱⁱ	0.97	2.59	3.361 (4)	136.7

Symmetry codes: (i) −x+1, −y+2, −z+1; (ii) −x+1, −y+1, −z+1; (iii) x+1, y, z.

Acknowledgements

The authors thank South China Normal University for financial support (grant Nos. SCNU033038 and SCNU524002).

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