Ethyl 6-amino-5-cyano-4-isopropyl-2-methyl-4H-pyran-3-carboxyl­ate

Messaâd, M.; Hamdi, B.; Chabchoub, F.; Ben Salah, A.; Salem, M.

doi:10.1107/S160053680804052X

organic compounds

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ISSN: 2056-9890

Volume 65| Part 1| January 2009| Page o39

doi:10.1107/S160053680804052X

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Ethyl 6-amino-5-cyano-4-isopropyl-2-methyl-4H-pyran-3-carboxylate

Mehdi Messaâd,^a Besma Hamdi,^b ^* Fakher Chabchoub,^a Abdelhamid Ben Salah ^b and Mansour Salem ^a

^aLaboratoire de Chimie Appliquée: Hétérocycles, Corps Gras et Polymères, Faculté des Sciences de Sfax, BP 1171, 3000 Sfax, Tunisia, and ^bLaboratoire des Sciences de Materiaux et d'Environnement, Faculté des Sciences de Sfax, BP 1171, 3000 Sfax, Tunisia
^*Correspondence e-mail: bh_hamdi2006@yahoo.fr

(Received 29 November 2008; accepted 2 December 2008; online 6 December 2008)

In the title compound, C₁₃H₁₈N₂O₃, the two H atoms of the NH₂ group are engaged in hydrogen bonding with the N atom of the cyano group and with one O atom of the ethoxycarbonyl group, building a chain parallel to the [100] direction. The N—H⋯N hydrogen bonds assemble the molecules around inversion centres, forming dimers with an R₂²(12) graph-set motif.

Related literature

For general background, see: Messaâd et al. (2005 , 2006 ); Mohr et al. (1975 ); Ohira & Yatagai (1993 ); Tandon et al. (1991 ); Wang et al. (1996 ); Zamocka et al. (1992 ); Bloxham et al. (1994 ); Elagamey et al. (1993 ); Khafagy et al. (2002 ). For graph-set notation, see: Etter (1990 ); Bernstein et al. (1994 ).

Experimental

Crystal data

C₁₃H₁₈N₂O₃
M_r = 250.29
Triclinic, $[P \overline 1]$
a = 8.0856 (1) Å
b = 9.3193 (2) Å
c = 10.4563 (2) Å
α = 65.652 (1)°
β = 69.679 (1)°
γ = 76.105 (1)°
V = 668.80 (2) Å³
Z = 2
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 296 K
0.44 × 0.36 × 0.18 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 1998 ) T_min = 0.959, T_max = 0.982
17876 measured reflections
4664 independent reflections
3324 reflections with I > 2σ(I)
R_int = 0.027

Refinement

R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.143
S = 1.05
4664 reflections
167 parameters
H-atom parameters constrained
Δρ_max = 0.24 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2A⋯O2ⁱ	0.86	2.08	2.9411 (11)	174
N2—H2B⋯N3ⁱⁱ	0.86	2.19	3.0269 (13)	164
Symmetry codes: (i) x+1, y, z; (ii) -x+1, -y, -z+1.

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 ), ORTEP-3 for Windows (Farrugia, 1997 ) and PLATON (Spek, 2003 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053680804052X/dn2412sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053680804052X/dn2412Isup2.hkl

checkCIF report

Comment top

The analysis of the bibliographical data shows that pyrans are biologically interesting compounds (Bloxham et al., 1994; Wang et al., 1996). In fact, some pyran derivatives present antibacterial activities (Zamocka et al., 1992; Ohira & Yatagai, 1993); antifungal activities (Mohr et al., 1975); antitumor activity (Tandon et al., 1991) and they can have an hypotensive effect (Elagamey et al., 1993). 2-amino-3-cyano-4H-pyrans are useful biphilic agents that lead to polycondensed pyranopyrimidines (Khafagy et al., 2002; Messaâd et al., 2005, 2006). In this paper we report for the first time the synthesis of 2-amino-3-cyano-5-ethoxycarbonyl-4-isopropyl-6-methyl-4H-pyran (3). This product was prepared via a standard addition of Michael of ethylacetoacetate (1) on α,β-ethylenic nitrile (2) in the presence of pyridine as a base (Scheme).

A view of the molecule is represented in Fig. 1. The two H atoms of the NH₂ group are engaged in hydrogen bondings with the nitrogen of the cyano group and with one O atom of the ethoxy group then building a chain developing parallel to the [100] direction (Table 1, Fig. 2). The N—H···N hydrogen bonds assemble the molecules around inversion centres to form pseudo-dimers with a R₂²(12) graph set motif (Etter, 1990; Bernstein et al., 1994).

Related literature top

For general background, see: Messaâd et al. (2005, 2006); Mohr et al. (1975); Ohira & Yatagai (1993); Tandon et al. (1991); Wang et al. (1996); Zamocka et al. (1992); Bloxham et al. (1994); Elagamey et al. (1993); Khafagy et al. (2002). For graph-set notation, see: Etter (1990); Bernstein et al. (1994).

Experimental top

A mixture containing 1.3 g (0.01 mol) of ethylacetoacetate and 1.2 g (0.01 mol) of α,β-ethylenic nitrile in 50 ml of ethanol was heated to reflux for 3 h. The solvent was removed under rotary evaporation. The crude product was washed with ether then filtered and recrystallized from ethanol to give analytically pure crystals. Yield 75%; m.p. 118°C. Spectroscopic analysis, IR: νCN: 2183 cm-1; νNH2: 3334–3398 cm-1; νC═O:1692 cm-1; 1H NMR (300 MHz; CDCl3, p.p.m.): 1.29 (t, 3 J = 7.5, 3H); 4.21 (q, 3 J = 7.5, 2H); 2.29 (s, 1H); 4.48 (s, 2H); 3.37(d, 3 J = 4.5, 1H); 1.82 (m, 1H); 0.81–0.97 (2 d, 3 J = 9, 6H); 13 C NMR (75 MHz; CDCl3, p.p.m.): 14.16; 16.93; 18.27; 19.62; 34.58; 38.66; 57.20; 60.71; 108.42; 120.42; 157.64; 160.23; 166.62.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. Molecular view of the title compound with the atom-labelling scheme. Ellispsoids are drawn at the 50% probability level. H atoms are represented as small spheres of arbitrary radii.
	Fig. 2. Partial packing view showing the formation of pseudo dimer through N—H···O and O—H···O hydrogen bonds. Hydrogen bonds are shown as dashed lines. [Symmetry codes: (i) 1 + x, y, z; (ii) 1 - x, -y, 1 - z]
	Fig. 3. The formation of the title compound.

Ethyl 6-amino-5-cyano-4-isopropyl-2-methyl-4H-pyran-3-carboxylate top

Crystal data top

C₁₃H₁₈N₂O₃	Z = 2
M_r = 250.29	F(000) = 268
Triclinic, P1	D_x = 1.243 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.0856 (1) Å	Cell parameters from 2132 reflections
b = 9.3193 (2) Å	θ = 2.3–21.2°
c = 10.4563 (2) Å	µ = 0.09 mm⁻¹
α = 65.652 (1)°	T = 296 K
β = 69.679 (1)°	Prism, colourless
γ = 76.105 (1)°	0.44 × 0.36 × 0.18 mm
V = 668.80 (2) Å³

Data collection top

Bruker SMART CCD area-detector diffractometer	4664 independent reflections
Radiation source: sealed tube	3324 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.027
ϕ and ω scans	θ_max = 32.1°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 1998)	h = −12→12
T_min = 0.959, T_max = 0.982	k = −13→12
17876 measured reflections	l = −15→14

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.143	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0801P)² + 0.026P] where P = (F_o² + 2F_c²)/3
4664 reflections	(Δ/σ)_max = 0.009
167 parameters	Δρ_max = 0.24 e Å⁻³
0 restraints	Δρ_min = −0.24 e Å⁻³

Crystal data top

C₁₃H₁₈N₂O₃	γ = 76.105 (1)°
M_r = 250.29	V = 668.80 (2) Å³
Triclinic, P1	Z = 2
a = 8.0856 (1) Å	Mo Kα radiation
b = 9.3193 (2) Å	µ = 0.09 mm⁻¹
c = 10.4563 (2) Å	T = 296 K
α = 65.652 (1)°	0.44 × 0.36 × 0.18 mm
β = 69.679 (1)°

Data collection top

Bruker SMART CCD area-detector diffractometer	4664 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 1998)	3324 reflections with I > 2σ(I)
T_min = 0.959, T_max = 0.982	R_int = 0.027
17876 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	0 restraints
wR(F²) = 0.143	H-atom parameters constrained
S = 1.05	Δρ_max = 0.24 e Å⁻³
4664 reflections	Δρ_min = −0.24 e Å⁻³
167 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 > 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
O1	0.36662 (8)	0.54982 (7)	0.29951 (8)	0.03977 (18)
O2	−0.23592 (10)	0.56365 (10)	0.34370 (11)	0.0559 (2)
O3	−0.12340 (9)	0.79434 (9)	0.22760 (9)	0.0463 (2)
N2	0.54618 (11)	0.33268 (10)	0.37642 (11)	0.0440 (2)
H2A	0.6161	0.3972	0.3631	0.053*
H2B	0.5773	0.2321	0.4080	0.053*
N3	0.29885 (15)	0.00436 (11)	0.48430 (13)	0.0583 (3)
C1	0.38924 (12)	0.38872 (11)	0.34801 (10)	0.0340 (2)
C2	0.26177 (12)	0.30627 (10)	0.36205 (10)	0.0341 (2)
C3	0.10119 (11)	0.39019 (10)	0.30733 (10)	0.03172 (19)
H3	−0.0020	0.3380	0.3801	0.038*
C4	0.07103 (11)	0.55961 (10)	0.29910 (10)	0.03243 (19)
C5	0.19954 (12)	0.63057 (10)	0.29517 (10)	0.0344 (2)
C6	−0.11029 (12)	0.63756 (12)	0.29492 (11)	0.0364 (2)
C7	−0.29880 (14)	0.87305 (14)	0.21657 (15)	0.0535 (3)
H7A	−0.3819	0.8524	0.3133	0.064*
H7B	−0.3409	0.8342	0.1618	0.064*
C8	−0.2844 (2)	1.04593 (17)	0.14025 (19)	0.0738 (4)
H8A	−0.2495	1.0843	0.1982	0.111*
H8B	−0.3973	1.1007	0.1264	0.111*
H8C	−0.1972	1.0644	0.0469	0.111*
C9	0.28332 (13)	0.13998 (11)	0.42860 (12)	0.0393 (2)
C10	0.19803 (15)	0.79274 (12)	0.28995 (14)	0.0471 (3)
H10A	0.0785	0.8439	0.3048	0.071*
H10B	0.2700	0.8531	0.1963	0.071*
H10C	0.2446	0.7859	0.3654	0.071*
C11	0.11157 (12)	0.38374 (12)	0.15880 (11)	0.0382 (2)
H11	0.0071	0.4499	0.1297	0.046*
C12	0.27420 (17)	0.45164 (17)	0.03829 (13)	0.0573 (3)
H12A	0.3795	0.3903	0.0639	0.086*
H12B	0.2728	0.5596	0.0266	0.086*
H12C	0.2730	0.4479	−0.0518	0.086*
C13	0.1026 (2)	0.21704 (15)	0.17254 (16)	0.0614 (3)
H13A	0.0852	0.2204	0.0850	0.092*
H13B	0.0054	0.1728	0.2548	0.092*
H13C	0.2116	0.1525	0.1865	0.092*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0361 (3)	0.0241 (3)	0.0613 (4)	−0.0051 (2)	−0.0227 (3)	−0.0092 (3)
O2	0.0355 (4)	0.0475 (5)	0.0925 (6)	−0.0084 (3)	−0.0162 (4)	−0.0320 (4)
O3	0.0353 (3)	0.0343 (4)	0.0665 (5)	0.0028 (3)	−0.0207 (3)	−0.0140 (3)
N2	0.0393 (4)	0.0292 (4)	0.0672 (6)	−0.0028 (3)	−0.0279 (4)	−0.0109 (4)
N3	0.0649 (6)	0.0298 (5)	0.0844 (8)	−0.0039 (4)	−0.0399 (6)	−0.0098 (5)
C1	0.0358 (4)	0.0255 (4)	0.0421 (5)	−0.0041 (3)	−0.0164 (4)	−0.0088 (3)
C2	0.0378 (4)	0.0246 (4)	0.0437 (5)	−0.0043 (3)	−0.0185 (4)	−0.0100 (3)
C3	0.0322 (4)	0.0248 (4)	0.0417 (4)	−0.0057 (3)	−0.0146 (3)	−0.0106 (3)
C4	0.0320 (4)	0.0264 (4)	0.0424 (5)	−0.0030 (3)	−0.0143 (3)	−0.0128 (3)
C5	0.0357 (4)	0.0258 (4)	0.0450 (5)	−0.0038 (3)	−0.0171 (4)	−0.0111 (3)
C6	0.0334 (4)	0.0343 (5)	0.0481 (5)	−0.0018 (3)	−0.0138 (4)	−0.0204 (4)
C7	0.0398 (5)	0.0505 (7)	0.0749 (8)	0.0106 (5)	−0.0261 (5)	−0.0276 (6)
C8	0.0675 (8)	0.0544 (8)	0.0838 (10)	0.0189 (6)	−0.0321 (7)	−0.0150 (7)
C9	0.0413 (5)	0.0289 (5)	0.0525 (5)	−0.0034 (4)	−0.0224 (4)	−0.0120 (4)
C10	0.0509 (5)	0.0294 (5)	0.0710 (7)	−0.0048 (4)	−0.0277 (5)	−0.0188 (5)
C11	0.0393 (5)	0.0369 (5)	0.0472 (5)	−0.0021 (4)	−0.0200 (4)	−0.0183 (4)
C12	0.0578 (7)	0.0678 (8)	0.0461 (6)	−0.0139 (6)	−0.0110 (5)	−0.0195 (6)
C13	0.0818 (9)	0.0518 (7)	0.0718 (8)	−0.0148 (6)	−0.0272 (7)	−0.0343 (6)

Geometric parameters (Å, º) top

O1—C1	1.3599 (11)	C7—C8	1.4871 (18)
O1—C5	1.3855 (11)	C7—H7A	0.9700
O2—C6	1.2053 (11)	C7—H7B	0.9700
O3—C6	1.3308 (12)	C8—H8A	0.9600
O3—C7	1.4516 (12)	C8—H8B	0.9600
N2—C1	1.3367 (11)	C8—H8C	0.9600
N2—H2A	0.8600	C10—H10A	0.9600
N2—H2B	0.8600	C10—H10B	0.9600
N3—C9	1.1489 (13)	C10—H10C	0.9600
C1—C2	1.3625 (12)	C11—C13	1.5172 (15)
C2—C9	1.4077 (13)	C11—C12	1.5194 (15)
C2—C3	1.5113 (12)	C11—H11	0.9800
C3—C4	1.5091 (12)	C12—H12A	0.9600
C3—C11	1.5513 (13)	C12—H12B	0.9600
C3—H3	0.9800	C12—H12C	0.9600
C4—C5	1.3404 (11)	C13—H13A	0.9600
C4—C6	1.4785 (12)	C13—H13B	0.9600
C5—C10	1.4868 (13)	C13—H13C	0.9600

C1—O1—C5	119.76 (7)	C7—C8—H8A	109.5
C6—O3—C7	116.29 (8)	C7—C8—H8B	109.5
C1—N2—H2A	120.0	H8A—C8—H8B	109.5
C1—N2—H2B	120.0	C7—C8—H8C	109.5
H2A—N2—H2B	120.0	H8A—C8—H8C	109.5
N2—C1—O1	110.47 (7)	H8B—C8—H8C	109.5
N2—C1—C2	128.56 (8)	N3—C9—C2	179.11 (13)
O1—C1—C2	120.97 (8)	C5—C10—H10A	109.5
C1—C2—C9	118.33 (8)	C5—C10—H10B	109.5
C1—C2—C3	121.20 (8)	H10A—C10—H10B	109.5
C9—C2—C3	120.47 (7)	C5—C10—H10C	109.5
C4—C3—C2	109.19 (7)	H10A—C10—H10C	109.5
C4—C3—C11	110.66 (7)	H10B—C10—H10C	109.5
C2—C3—C11	114.29 (8)	C13—C11—C12	110.81 (10)
C4—C3—H3	107.5	C13—C11—C3	111.65 (9)
C2—C3—H3	107.5	C12—C11—C3	112.53 (8)
C11—C3—H3	107.5	C13—C11—H11	107.2
C5—C4—C6	124.13 (8)	C12—C11—H11	107.2
C5—C4—C3	121.99 (8)	C3—C11—H11	107.2
C6—C4—C3	113.88 (7)	C11—C12—H12A	109.5
C4—C5—O1	120.88 (8)	C11—C12—H12B	109.5
C4—C5—C10	130.87 (9)	H12A—C12—H12B	109.5
O1—C5—C10	108.23 (7)	C11—C12—H12C	109.5
O2—C6—O3	122.42 (8)	H12A—C12—H12C	109.5
O2—C6—C4	122.32 (9)	H12B—C12—H12C	109.5
O3—C6—C4	115.19 (7)	C11—C13—H13A	109.5
O3—C7—C8	107.55 (10)	C11—C13—H13B	109.5
O3—C7—H7A	110.2	H13A—C13—H13B	109.5
C8—C7—H7A	110.2	C11—C13—H13C	109.5
O3—C7—H7B	110.2	H13A—C13—H13C	109.5
C8—C7—H7B	110.2	H13B—C13—H13C	109.5
H7A—C7—H7B	108.5

C5—O1—C1—N2	−165.46 (8)	C6—C4—C5—C10	1.72 (18)
C5—O1—C1—C2	14.55 (14)	C3—C4—C5—C10	−178.70 (10)
N2—C1—C2—C9	7.28 (17)	C1—O1—C5—C4	−18.29 (14)
O1—C1—C2—C9	−172.73 (9)	C1—O1—C5—C10	160.34 (9)
N2—C1—C2—C3	−172.47 (10)	C7—O3—C6—O2	0.41 (16)
O1—C1—C2—C3	7.52 (15)	C7—O3—C6—C4	177.50 (9)
C1—C2—C3—C4	−23.01 (13)	C5—C4—C6—O2	−155.83 (11)
C9—C2—C3—C4	157.24 (9)	C3—C4—C6—O2	24.56 (14)
C1—C2—C3—C11	101.52 (11)	C5—C4—C6—O3	27.08 (14)
C9—C2—C3—C11	−78.22 (11)	C3—C4—C6—O3	−152.53 (9)
C2—C3—C4—C5	19.51 (13)	C6—O3—C7—C8	179.26 (11)
C11—C3—C4—C5	−107.12 (10)	C4—C3—C11—C13	−167.94 (8)
C2—C3—C4—C6	−160.87 (8)	C2—C3—C11—C13	68.32 (10)
C11—C3—C4—C6	72.50 (9)	C4—C3—C11—C12	66.72 (11)
C3—C4—C5—O1	−0.42 (14)	C2—C3—C11—C12	−57.03 (11)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···O2ⁱ	0.86	2.08	2.9411 (11)	174
N2—H2B···N3ⁱⁱ	0.86	2.19	3.0269 (13)	164

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

Experimental details

Crystal data
Chemical formula	C₁₃H₁₈N₂O₃
M_r	250.29
Crystal system, space group	Triclinic, P1
Temperature (K)	296
a, b, c (Å)	8.0856 (1), 9.3193 (2), 10.4563 (2)
α, β, γ (°)	65.652 (1), 69.679 (1), 76.105 (1)
V (Å³)	668.80 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.44 × 0.36 × 0.18

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 1998)
T_min, T_max	0.959, 0.982
No. of measured, independent and observed [I > 2σ(I)] reflections	17876, 4664, 3324
R_int	0.027
(sin θ/λ)_max (Å⁻¹)	0.748

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.143, 1.05
No. of reflections	4664
No. of parameters	167
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.24, −0.24

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···O2ⁱ	0.86	2.08	2.9411 (11)	174.3
N2—H2B···N3ⁱⁱ	0.86	2.19	3.0269 (13)	163.6

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

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