Ethyl 2-amino-4-(3-nitro­phen­yl)-4H-1-benzothieno[3,2-b]pyran-3-carboxyl­ate

Bakhouch, M.; Al Houari, G.; El Yazidi, M.; Saadi, M.; El Ammari, L.

doi:10.1107/S1600536814008538

organic compounds

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ISSN: 2056-9890

Volume 70| Part 5| May 2014| Page o587

doi:10.1107/S1600536814008538

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Ethyl 2-amino-4-(3-nitrophenyl)-4H-1-benzothieno[3,2-b]pyran-3-carboxylate

Mohamed Bakhouch,^a Ghali Al Houari,^a Mohamed El Yazidi,^a ^* Mohamed Saadi ^b and Lahcen El Ammari ^b

^aDépartement de Chimie, Faculté des Sciences, Dhar Mehraz, BP 1796 Atlas, 30000 Fes, Morocco, and ^bLaboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V-Agdal, Avenue Ibn Battouta, BP 1014, Rabat, Morocco
^*Correspondence e-mail: elyazidimohamed@hotmail.com

(Received 9 April 2014; accepted 15 April 2014; online 18 April 2014)

The molecule of the title compound, C₂₀H₁₆N₂O₅S, is built up by one fused five-membered and two fused six-membered rings linked to ethoxycarbonyl and 3-nitrophenyl groups. The benzothienopyran ring system is nearly planar (r.m.s deviation = 0.0392 Å) and forms a dihedral angle of 86.90 (6)° with the aromatic ring of the nitrobenzene group. In the crystal, molecules are linked by N—H⋯O hydrogen bonds and by π–π interactions between the phenyl ring and the six-membered heterocyle [intercentroid distance = 3.5819 (8) Å], forming a three-dimensional network.

CCDC reference: 997474

Related literature

For background to the organic synthesis of the title compound, see: House (1972 ); Kabashima et al. (2000 ); Jung (1991 ). For the preparation of heterocyclic compounds using condensation reactions, see: Boughaleb et al. (2011 ); Cabiddu et al. (2002 ); Pradhan & Asish (2005 ).

Experimental

Crystal data

C₂₀H₁₆N₂O₅S
M_r = 396.41
Triclinic, $[P \overline 1]$
a = 8.3670 (2) Å
b = 9.4319 (2) Å
c = 12.8948 (4) Å
α = 102.505 (1)°
β = 106.493 (1)°
γ = 94.840 (1)°
V = 940.96 (4) Å³
Z = 2
Mo Kα radiation
μ = 0.21 mm⁻¹
T = 296 K
0.42 × 0.31 × 0.26 mm

Data collection

Bruker X8 APEX diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.673, T_max = 0.746
20668 measured reflections
4857 independent reflections
3954 reflections with I > 2σ(I)
R_int = 0.025

Refinement

R[F² > 2σ(F²)] = 0.044
wR(F²) = 0.137
S = 1.05
4857 reflections
253 parameters
H-atom parameters constrained
Δρ_max = 0.37 e Å⁻³
Δρ_min = −0.25 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1B⋯O2	0.86	2.09	2.6950 (17)	127
N1—H1B⋯O2ⁱ	0.86	2.30	3.0327 (17)	143
N1—H1A⋯O5ⁱⁱ	0.86	2.30	3.1489 (19)	169
Symmetry codes: (i) -x+1, -y+2, -z; (ii) x+1, y+1, z.

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ); software used to prepare material for publication: PLATON (Spek, 2009 ) and publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 997474

Crystal structure: contains datablock I. DOI: 10.1107/S1600536814008538/rz5118sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536814008538/rz5118Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536814008538/rz5118Isup3.cml

checkCIF report

Comment top

The Michael reaction is one of the most efficient methods for effecting carbon–carbon bond formation and has wide synthetic applications (House, 1972; Kabashima et al., 2000). This reaction and its close variants have been extensively used in organic synthesis (Jung, 1991). Generally, Michael additions are conducted in a suitable solvent in the presence of a strong base either at room or at elevated temperatures. In continuing our previous works on the preparation of hetrocyclic compounds by using condensation reactions (Boughaleb et al., 2011), we now wish to describe the behavior of ethylcyanoacetate with respect to (Z)-2-(3-nitrobenzylidene)-1-benzo[b]thiophen-3(2H)-one and derivatives in ethanol, with the presence of piperidine as a basic catalyst (Cabiddu et al., 2002; Pradhan & Asish, 2005). We have shown that cyclocondensation start with a Michael 1,4-additon, followed by intramolecular cyclization via nucleophilic addition of the hydroxyl group to the cyano group and not onto the carboxylate, to afford the tricyclic heterocycle ethyl2-amino-4-(3-nitrophenyl)-4H-1-benzothieno[3,2-b]pyran-3-carboxylate.

The molecule of the title compound, is formed by tree fused rings linked to an ethyl-3-carboxylate nd a 3-nitrophenyl group as shown in Fig. 1. The three fused rings (S1/C1–C11/O1) are almost coplanar, with the maximum deviation from the mean plane of -0.089 (2) Å at C9, and make a dihedral angle of 86.90 (6)° with the plane through the attached nitrophenyl group.

In the crystal, molecules are linked by N—H···O hydrogen bonds and by π–π interactions in a three-dimensional network as shown in Fig. 2 and Table 1.

Related literature top

For background to the organic synthesis of the title compound, see: House (1972); Kabashima et al. (2000); Jung (1991). For the preparation of hetrocyclic compounds using condensation reactions, see: Boughaleb et al. (2011); Cabiddu et al. (2002); Pradhan & Asish (2005).

Experimental top

In a 100 ml flask equipped with a condenser was dissolved 4 mmol of (Z)-2-(3-nitrobenzylidene)-1-benzo[b]thiophen-3(2H)-one and 5 mmol of ethyl cyanoacetate in 30 ml of ethanol. Then, 1 ml of piperidine was added, and the reaction mixture was refluxed for 6 h. Thin layer chromatography revealed the formation of a single product. The organic phase was evaporated under reduce pressure. The resulting residue was recristallized from ethanol (Yield: 68%; m.p.: 493 K).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Figures top

	Fig. 1. The molecular structure of the title compound with displacement ellipsoids drawn at the 50% probability level. H atoms are represented as small circles.
	Fig. 2. Partial crystal packing for the title compound showing molecules linked by hydrogen bonds (dashed lines).

Ethyl 2-amino-4-(3-nitrophenyl)-4H-1-benzothieno[3,2-b]pyran-3-carboxylate top

Crystal data top

C₂₀H₁₆N₂O₅S	Z = 2
M_r = 396.41	F(000) = 412
Triclinic, P1	D_x = 1.399 Mg m⁻³
Hall symbol: -P 1	Melting point: 493 K
a = 8.3670 (2) Å	Mo Kα radiation, λ = 0.71073 Å
b = 9.4319 (2) Å	Cell parameters from 4857 reflections
c = 12.8948 (4) Å	θ = 2.5–28.7°
α = 102.505 (1)°	µ = 0.21 mm⁻¹
β = 106.493 (1)°	T = 296 K
γ = 94.840 (1)°	Block, colourless
V = 940.96 (4) Å³	0.42 × 0.31 × 0.26 mm

Data collection top

Bruker X8 APEX diffractometer	4857 independent reflections
Radiation source: fine-focus sealed tube	3954 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.025
ϕ and ω scans	θ_max = 28.7°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −11→11
T_min = 0.673, T_max = 0.746	k = −12→12
20668 measured reflections	l = −17→17

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.137	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0782P)² + 0.1615P] where P = (F_o² + 2F_c²)/3
4857 reflections	(Δ/σ)_max = 0.001
253 parameters	Δρ_max = 0.37 e Å⁻³
0 restraints	Δρ_min = −0.25 e Å⁻³

Crystal data top

C₂₀H₁₆N₂O₅S	γ = 94.840 (1)°
M_r = 396.41	V = 940.96 (4) Å³
Triclinic, P1	Z = 2
a = 8.3670 (2) Å	Mo Kα radiation
b = 9.4319 (2) Å	µ = 0.21 mm⁻¹
c = 12.8948 (4) Å	T = 296 K
α = 102.505 (1)°	0.42 × 0.31 × 0.26 mm
β = 106.493 (1)°

Data collection top

Bruker X8 APEX diffractometer	4857 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	3954 reflections with I > 2σ(I)
T_min = 0.673, T_max = 0.746	R_int = 0.025
20668 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.044	0 restraints
wR(F²) = 0.137	H-atom parameters constrained
S = 1.05	Δρ_max = 0.37 e Å⁻³
4857 reflections	Δρ_min = −0.25 e Å⁻³
253 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

	x	y	z	U_iso*/U_eq
C1	1.03581 (19)	0.74569 (16)	0.51586 (12)	0.0444 (3)
C2	1.1714 (2)	0.7184 (2)	0.59752 (14)	0.0572 (4)
H2	1.1539	0.6646	0.6469	0.069*
C3	1.3318 (2)	0.7739 (2)	0.60256 (14)	0.0596 (4)
H3	1.4239	0.7566	0.6561	0.072*
C4	1.3590 (2)	0.8552 (2)	0.52938 (14)	0.0553 (4)
H4	1.4689	0.8908	0.5347	0.066*
C5	1.22638 (19)	0.88383 (17)	0.44927 (13)	0.0472 (3)
H5	1.2455	0.9388	0.4010	0.057*
C6	1.06239 (17)	0.82841 (14)	0.44214 (11)	0.0388 (3)
C7	0.90329 (17)	0.83869 (14)	0.36665 (11)	0.0366 (3)
C8	0.76677 (17)	0.76734 (14)	0.37893 (11)	0.0373 (3)
C9	0.59063 (16)	0.75463 (14)	0.30354 (11)	0.0356 (3)
H9	0.5205	0.7943	0.3487	0.043*
C10	0.59569 (16)	0.84817 (14)	0.22130 (11)	0.0361 (3)
C11	0.74244 (17)	0.91953 (14)	0.21693 (11)	0.0371 (3)
C12	0.43789 (18)	0.86851 (15)	0.14814 (12)	0.0418 (3)
C13	0.1380 (2)	0.8102 (3)	0.0990 (2)	0.0859 (7)
H13A	0.1389	0.8011	0.0228	0.103*
H13B	0.1031	0.9034	0.1248	0.103*
C14	0.0200 (2)	0.6887 (2)	0.1031 (2)	0.0785 (6)
H14A	−0.0914	0.6910	0.0564	0.118*
H14B	0.0192	0.6988	0.1787	0.118*
H14C	0.0549	0.5969	0.0770	0.118*
C15	0.51766 (16)	0.59335 (14)	0.24462 (11)	0.0363 (3)
C16	0.5980 (2)	0.50862 (16)	0.17907 (13)	0.0486 (3)
H16	0.6969	0.5507	0.1710	0.058*
C17	0.5336 (2)	0.36266 (18)	0.12555 (16)	0.0598 (4)
H17	0.5895	0.3077	0.0820	0.072*
C18	0.3863 (2)	0.29794 (17)	0.13649 (15)	0.0592 (5)
H18	0.3414	0.2000	0.1008	0.071*
C19	0.30905 (19)	0.38353 (17)	0.20176 (14)	0.0516 (4)
C20	0.37110 (17)	0.52953 (16)	0.25679 (12)	0.0439 (3)
H20	0.3155	0.5835	0.3010	0.053*
N1	0.75846 (17)	0.99963 (14)	0.14576 (11)	0.0500 (3)
H1A	0.8569	1.0394	0.1494	0.060*
H1B	0.6704	1.0114	0.0963	0.060*
N2	0.1493 (2)	0.3189 (2)	0.21188 (16)	0.0745 (5)
O1	0.89774 (12)	0.91629 (11)	0.28705 (8)	0.0435 (2)
O2	0.41926 (14)	0.93260 (13)	0.07393 (10)	0.0551 (3)
O3	0.30471 (13)	0.80479 (15)	0.16981 (11)	0.0597 (3)
O4	0.0661 (2)	0.3993 (2)	0.2526 (2)	0.1098 (7)
O5	0.1064 (2)	0.1868 (2)	0.17700 (19)	0.1165 (7)
S1	0.82193 (5)	0.68473 (5)	0.48947 (3)	0.05225 (14)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0450 (7)	0.0467 (7)	0.0397 (7)	0.0057 (6)	0.0084 (6)	0.0138 (6)
C2	0.0577 (10)	0.0676 (10)	0.0468 (8)	0.0126 (8)	0.0067 (7)	0.0273 (7)
C3	0.0479 (9)	0.0773 (11)	0.0482 (9)	0.0150 (8)	0.0012 (7)	0.0211 (8)
C4	0.0391 (8)	0.0712 (10)	0.0487 (9)	0.0056 (7)	0.0063 (6)	0.0119 (7)
C5	0.0410 (7)	0.0539 (8)	0.0423 (7)	0.0017 (6)	0.0072 (6)	0.0130 (6)
C6	0.0404 (7)	0.0371 (6)	0.0342 (6)	0.0037 (5)	0.0068 (5)	0.0064 (5)
C7	0.0392 (7)	0.0346 (6)	0.0343 (6)	0.0025 (5)	0.0082 (5)	0.0107 (5)
C8	0.0394 (7)	0.0373 (6)	0.0343 (6)	0.0030 (5)	0.0083 (5)	0.0126 (5)
C9	0.0349 (6)	0.0380 (6)	0.0360 (6)	0.0032 (5)	0.0121 (5)	0.0129 (5)
C10	0.0377 (7)	0.0355 (6)	0.0373 (6)	0.0054 (5)	0.0113 (5)	0.0139 (5)
C11	0.0380 (6)	0.0356 (6)	0.0386 (7)	0.0054 (5)	0.0106 (5)	0.0131 (5)
C12	0.0388 (7)	0.0452 (7)	0.0477 (8)	0.0116 (5)	0.0156 (6)	0.0197 (6)
C13	0.0361 (9)	0.1282 (19)	0.1168 (18)	0.0216 (10)	0.0176 (10)	0.0839 (16)
C14	0.0483 (10)	0.0803 (13)	0.0881 (15)	0.0057 (9)	0.0018 (10)	0.0096 (11)
C15	0.0341 (6)	0.0387 (6)	0.0365 (6)	0.0011 (5)	0.0075 (5)	0.0166 (5)
C16	0.0476 (8)	0.0441 (7)	0.0552 (9)	0.0014 (6)	0.0198 (7)	0.0119 (6)
C17	0.0684 (11)	0.0455 (8)	0.0610 (10)	0.0067 (7)	0.0188 (9)	0.0067 (7)
C18	0.0655 (10)	0.0412 (7)	0.0560 (9)	−0.0078 (7)	−0.0024 (8)	0.0160 (7)
C19	0.0409 (7)	0.0545 (8)	0.0533 (8)	−0.0106 (6)	−0.0014 (6)	0.0292 (7)
C20	0.0358 (7)	0.0509 (7)	0.0467 (8)	−0.0001 (6)	0.0094 (6)	0.0228 (6)
N1	0.0416 (6)	0.0573 (7)	0.0569 (8)	0.0010 (5)	0.0113 (6)	0.0342 (6)
N2	0.0517 (9)	0.0814 (11)	0.0832 (11)	−0.0221 (8)	0.0030 (8)	0.0424 (9)
O1	0.0356 (5)	0.0502 (5)	0.0465 (5)	−0.0001 (4)	0.0085 (4)	0.0239 (4)
O2	0.0458 (6)	0.0699 (7)	0.0608 (7)	0.0148 (5)	0.0145 (5)	0.0404 (6)
O3	0.0343 (5)	0.0866 (8)	0.0737 (8)	0.0155 (5)	0.0171 (5)	0.0496 (7)
O4	0.0650 (10)	0.1204 (15)	0.1621 (19)	−0.0096 (10)	0.0533 (12)	0.0581 (14)
O5	0.0925 (12)	0.0841 (11)	0.1571 (18)	−0.0447 (9)	0.0255 (12)	0.0378 (11)
S1	0.0472 (2)	0.0633 (3)	0.0485 (2)	−0.00050 (17)	0.00801 (16)	0.03121 (18)

Geometric parameters (Å, º) top

C1—C2	1.396 (2)	C12—O3	1.3482 (17)
C1—C6	1.405 (2)	C13—O3	1.446 (2)
C1—S1	1.7449 (16)	C13—C14	1.469 (3)
C2—C3	1.377 (3)	C13—H13A	0.9700
C2—H2	0.9300	C13—H13B	0.9700
C3—C4	1.392 (3)	C14—H14A	0.9600
C3—H3	0.9300	C14—H14B	0.9600
C4—C5	1.376 (2)	C14—H14C	0.9600
C4—H4	0.9300	C15—C20	1.3843 (18)
C5—C6	1.397 (2)	C15—C16	1.388 (2)
C5—H5	0.9300	C16—C17	1.383 (2)
C6—C7	1.4338 (18)	C16—H16	0.9300
C7—C8	1.3423 (18)	C17—C18	1.386 (3)
C7—O1	1.3768 (15)	C17—H17	0.9300
C8—C9	1.4959 (18)	C18—C19	1.371 (3)
C8—S1	1.7378 (14)	C18—H18	0.9300
C9—C10	1.5261 (17)	C19—C20	1.384 (2)
C9—C15	1.5308 (17)	C19—N2	1.473 (2)
C9—H9	0.9800	C20—H20	0.9300
C10—C11	1.3712 (18)	N1—H1A	0.8600
C10—C12	1.4436 (19)	N1—H1B	0.8600
C11—N1	1.3356 (17)	N2—O4	1.208 (3)
C11—O1	1.3633 (16)	N2—O5	1.214 (2)
C12—O2	1.2195 (17)

C2—C1—C6	120.99 (15)	O3—C13—C14	108.58 (16)
C2—C1—S1	127.04 (13)	O3—C13—H13A	110.0
C6—C1—S1	111.96 (11)	C14—C13—H13A	110.0
C3—C2—C1	117.84 (16)	O3—C13—H13B	110.0
C3—C2—H2	121.1	C14—C13—H13B	110.0
C1—C2—H2	121.1	H13A—C13—H13B	108.4
C2—C3—C4	121.46 (15)	C13—C14—H14A	109.5
C2—C3—H3	119.3	C13—C14—H14B	109.5
C4—C3—H3	119.3	H14A—C14—H14B	109.5
C5—C4—C3	121.21 (16)	C13—C14—H14C	109.5
C5—C4—H4	119.4	H14A—C14—H14C	109.5
C3—C4—H4	119.4	H14B—C14—H14C	109.5
C4—C5—C6	118.47 (15)	C20—C15—C16	119.01 (13)
C4—C5—H5	120.8	C20—C15—C9	120.39 (12)
C6—C5—H5	120.8	C16—C15—C9	120.59 (11)
C5—C6—C1	120.03 (13)	C17—C16—C15	121.20 (15)
C5—C6—C7	130.31 (13)	C17—C16—H16	119.4
C1—C6—C7	109.65 (12)	C15—C16—H16	119.4
C8—C7—O1	124.23 (12)	C16—C17—C18	120.27 (17)
C8—C7—C6	115.68 (12)	C16—C17—H17	119.9
O1—C7—C6	120.09 (11)	C18—C17—H17	119.9
C7—C8—C9	124.19 (12)	C19—C18—C17	117.59 (14)
C7—C8—S1	111.37 (10)	C19—C18—H18	121.2
C9—C8—S1	124.38 (10)	C17—C18—H18	121.2
C8—C9—C10	107.83 (10)	C18—C19—C20	123.38 (14)
C8—C9—C15	110.43 (11)	C18—C19—N2	118.73 (15)
C10—C9—C15	112.40 (10)	C20—C19—N2	117.87 (17)
C8—C9—H9	108.7	C19—C20—C15	118.54 (15)
C10—C9—H9	108.7	C19—C20—H20	120.7
C15—C9—H9	108.7	C15—C20—H20	120.7
C11—C10—C12	118.22 (12)	C11—N1—H1A	120.0
C11—C10—C9	123.25 (12)	C11—N1—H1B	120.0
C12—C10—C9	118.45 (11)	H1A—N1—H1B	120.0
N1—C11—O1	109.61 (11)	O4—N2—O5	123.09 (19)
N1—C11—C10	127.07 (13)	O4—N2—C19	118.92 (16)
O1—C11—C10	123.32 (12)	O5—N2—C19	118.0 (2)
O2—C12—O3	121.52 (13)	C11—O1—C7	116.95 (10)
O2—C12—C10	126.91 (13)	C12—O3—C13	117.57 (13)
O3—C12—C10	111.56 (12)	C8—S1—C1	91.31 (7)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1B···O2	0.86	2.09	2.6950 (17)	127
N1—H1B···O2ⁱ	0.86	2.30	3.0327 (17)	143
N1—H1A···O5ⁱⁱ	0.86	2.30	3.1489 (19)	169

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1B···O2	0.86	2.09	2.6950 (17)	127.3
N1—H1B···O2ⁱ	0.86	2.30	3.0327 (17)	143.0
N1—H1A···O5ⁱⁱ	0.86	2.30	3.1489 (19)	168.9

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

Acknowledgements

The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.

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