8-Hydr­oxy-5,6,7-trimeth­oxy-2-phenyl-4H-chromen-4-one

Theodoro, J.E.; Santos, D.; Pérez, H.; Silva, M.F. das G.F. da; Ellena, J.

doi:10.1107/S1600536808010696

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 64| Part 5| May 2008| Page o899

doi:10.1107/S1600536808010696

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8-Hydroxy-5,6,7-trimethoxy-2-phenyl-4H-chromen-4-one

Jahyr E. Theodoro,^a Djalma Santos,^b Hiram Pérez,^c ^* Maria Fátima das Graças Fernandes da Silva ^b and J. Ellena ^a

^aInstituto de Física de São Carlos-USP, Cx Postal 369, 13560-970 São Carlos, SP, Brazil, ^bDepartamento Química-UFSCar, Cx Postal 676, 13565-905 São Carlos, SP, Brazil, and ^cDepartamento de Química Inorgánica, Facultad de Química, Universidad de la Habana, Habana 10400, Cuba
^*Correspondence e-mail: hperez@fq.uh.cu

(Received 28 March 2008; accepted 17 April 2008; online 23 April 2008)

In the title compound, C₁₈H₁₆O₆, the benzopyran group is essentially planar, with the O atoms of the substituent groups lying close to its mean plane. The molecular conformation is governed by intramolecular interactions. The crystal packing is mainly determined by one classical intermolecular hydrogen bond which gives rise to the formation of an infinite chain along the a axis.

Related literature

For related literature, see: Chebib & Johnston (2000 ); Medina et al. (1998 ).

Experimental

Crystal data

C₁₈H₁₆O₆
M_r = 328.32
Triclinic, $[P \overline 1]$
a = 8.4536 (2) Å
b = 9.0878 (2) Å
c = 10.7832 (3) Å
α = 79.545 (2)°
β = 71.5640 (10)°
γ = 86.925 (2)°
V = 772.85 (3) Å³
Z = 2
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 294 K
0.22 × 0.19 × 0.11 mm

Data collection

Nonius Kappa CCD diffractometer
Absorption correction: none
20499 measured reflections
3153 independent reflections
2512 reflections with I > 2σ(I)
R_int = 0.049

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.123
S = 1.07
3153 reflections
218 parameters
H-atom parameters constrained
Δρ_max = 0.25 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
O6—H8⋯O5	0.82	2.35	2.770 (1)	113
O6—H8⋯O2ⁱ	0.82	1.94	2.727 (1)	160
Symmetry code: (i) x+1, y, z.

Data collection: COLLECT (Nonius, 2000 ); cell refinement: COLLECT; data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997 ); 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, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808010696/bg2176sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808010696/bg2176Isup2.hkl

checkCIF report

Comment top

A number of differents flavones are known to have interesting modulatory activities at Gamma-aminobutyric acid receptors (GABA-A), an inhibitory neurotransmitter found in the nervous systems of widely divergent species. It is the main inhibitory neurotransmitter in the central nervous system (Medina et al., 1998; Chebib & Johnston, 2000).

Figure 1 shows an ORTEP view of thr title compound, 8-hydroxy-5,6,7-trymethoxy-2-phenylchromen-4-one (I) with atom labeling and 50% probability displacement ellipsoids. The benzopyran group in (I) is essentially planar, with the oxygen atoms of the substituent groups lying close to its mean plane. The ring forms angles of 113.8 (4)°, 117.8 (3)° and 114.4 (2)° with the O3—C16, O4—C17 and O5—C18 methoxy groups, respectively, and 34.61 (4)° with the phenyl ring.

The molecular conformation is fixed by intramolecular interactions (Table 1 and Figure 1). The crystal packing is mainly determined by one classical intermolecular H bond which gives rise to the formation of an infinite chain along the a axis (Table 1 and Figure 2).

Related literature top

For related literature, see: Chebib & Johnston (2000); Medina et al. (1998).

Experimental top

Selected parts of the Z. montana plant (Branches and leaves) were dried carefully by forced air at 40 °C and reduced to powder. The resulting material was macerated three times with hexane, followed with methanol at room temperature for 72 h each. After the evaporation of the solvent under reduced pressure, crude extracts were obtained. A well shaped single-crystal of the title compound was selected for the XRD experiments.

Computing details top

Data collection: COLLECT (Enraf–Nonius, 2000); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); 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, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. View of (I) (50% probability displacement ellipsoids)
	Fig. 2. View of the intermolecular interaction that gives rise to the formation of a chain along the a axis.

8-Hydroxy-5,6,7-trimethoxy-2-phenyl-4H-chromen-4-one top

Crystal data top

C₁₈H₁₆O₆	Z = 2
M_r = 328.32	F(000) = 344
Triclinic, P1	D_x = 1.411 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.4536 (2) Å	Cell parameters from 20513 reflections
b = 9.0878 (2) Å	θ = 2.9–26.4°
c = 10.7832 (3) Å	µ = 0.11 mm⁻¹
α = 79.545 (2)°	T = 294 K
β = 71.564 (1)°	Prism, yellow
γ = 86.925 (2)°	0.22 × 0.19 × 0.11 mm
V = 772.85 (3) Å³

Data collection top

KappaCCD diffractometer	R_int = 0.049
ϕ scans and ω scans winth κ offsets	θ_max = 26.4°, θ_min = 3.3°
20499 measured reflections	h = −10→10
3153 independent reflections	k = −11→11
2512 reflections with I > 2σ(I)	l = −13→13

Refinement top

Refinement on F²	H-atom parameters constrained
Least-squares matrix: full	w = 1/[σ²(F_o²) + (0.0678P)² + 0.1467P] where P = (F_o² + 2F_c²)/3
R[F² > 2σ(F²)] = 0.042	(Δ/σ)_max < 0.001
wR(F²) = 0.124	Δρ_max = 0.25 e Å⁻³
S = 1.07	Δρ_min = −0.24 e Å⁻³
3153 reflections	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
218 parameters	Extinction coefficient: 0.043 (11)
0 restraints

Crystal data top

C₁₈H₁₆O₆	γ = 86.925 (2)°
M_r = 328.32	V = 772.85 (3) Å³
Triclinic, P1	Z = 2
a = 8.4536 (2) Å	Mo Kα radiation
b = 9.0878 (2) Å	µ = 0.11 mm⁻¹
c = 10.7832 (3) Å	T = 294 K
α = 79.545 (2)°	0.22 × 0.19 × 0.11 mm
β = 71.564 (1)°

Data collection top

KappaCCD diffractometer	2512 reflections with I > 2σ(I)
20499 measured reflections	R_int = 0.049
3153 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	0 restraints
wR(F²) = 0.124	H-atom parameters constrained
S = 1.07	Δρ_max = 0.25 e Å⁻³
3153 reflections	Δρ_min = −0.24 e Å⁻³
218 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.40508 (11)	0.55938 (11)	0.19334 (9)	0.0343 (3)
O2	0.05483 (13)	0.68927 (14)	0.00920 (12)	0.0550 (3)
O3	0.29650 (12)	0.85689 (12)	−0.19401 (10)	0.0428 (3)
O4	0.63074 (13)	0.94104 (12)	−0.28518 (10)	0.0441 (3)
O5	0.83892 (11)	0.83118 (11)	−0.14212 (9)	0.0362 (3)
O6	0.71943 (11)	0.63816 (12)	0.09768 (9)	0.0395 (3)
C1	0.16504 (16)	0.64776 (16)	0.06016 (15)	0.0350 (3)
C2	0.13054 (16)	0.54641 (16)	0.18467 (14)	0.0368 (3)
C3	0.24520 (16)	0.50867 (15)	0.24709 (13)	0.0330 (3)
C4	0.45089 (16)	0.65179 (15)	0.07187 (13)	0.0 (3)
C5	0.33896 (15)	0.70155 (15)	0.00135 (13)	0.0301 (3)
C6	0.39952 (16)	0.80083 (15)	−0.12037 (13)	0.0320 (3)
C7	0.56421 (16)	0.84828 (15)	−0.16628 (13)	0.0313 (3)
C8	0.67300 (15)	0.79300 (15)	−0.09404 (13)	0.0296 (3)
C9	0.61900 (15)	0.69429 (15)	0.02441 (13)	0.0295 (3)
C10	0.21737 (17)	0.41557 (16)	0.37915 (13)	0.0353 (3)
C11	0.30333 (19)	0.44556 (19)	0.46281 (16)	0.0459 (4)
C12	0.2755 (2)	0.3598 (2)	0.58706 (16)	0.0547 (5)
C13	0.1650 (2)	0.2423 (2)	0.62864 (17)	0.0552 (5)
C14	0.0795 (2)	0.2109 (2)	0.54662 (17)	0.0573 (5)
C15	0.1043 (2)	0.29793 (19)	0.42257 (16)	0.0469 (4)
C16	0.2848 (3)	0.7646 (3)	−0.2840 (2)	0.0738 (6)
C17	0.5601 (3)	1.0840 (2)	−0.3033 (2)	0.0708 (6)
C18	0.8774 (2)	0.96476 (19)	−0.10671 (19)	0.0514 (4)
H8	0.8139	0.672	0.0606	0.059*
H8A	0.0242	0.5052	0.2237	0.044*
H17	0.3799	0.5239	0.4346	0.055*
H18	0.3319	0.3816	0.6429	0.066*
H19	0.1477	0.1839	0.7121	0.066*
H20	0.0049	0.131	0.5748	0.069*
H21	0.045	0.2774	0.3682	0.056*
H22A	0.9951	0.9838	−0.1435	0.077*
H22B	0.8451	0.9539	−0.0118	0.077*
H22C	0.818	1.0469	−0.1409	0.077*
H27A	0.2116	0.8102	−0.3321	0.111*
H27B	0.2415	0.6682	−0.2355	0.111*
H27C	0.3934	0.753	−0.3452	0.111*
H30A	0.6176	1.1374	−0.3902	0.106*
H30B	0.5701	1.1381	−0.2375	0.106*
H30C	0.4444	1.074	−0.2946	0.106*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0240 (5)	0.0430 (6)	0.0331 (5)	−0.0036 (4)	−0.0093 (4)	0.0024 (4)
O2	0.0248 (5)	0.0739 (8)	0.0630 (7)	−0.0045 (5)	−0.0224 (5)	0.0132 (6)
O3	0.0334 (5)	0.0540 (6)	0.0446 (6)	0.0043 (5)	−0.0228 (5)	0.0007 (5)
O4	0.0364 (6)	0.0472 (6)	0.0381 (6)	0.0029 (4)	−0.0061 (4)	0.0083 (5)
O5	0.0218 (5)	0.0456 (6)	0.0403 (5)	−0.0040 (4)	−0.0082 (4)	−0.0067 (4)
O6	0.0240 (5)	0.0570 (6)	0.0364 (5)	−0.0039 (4)	−0.0151 (4)	0.0057 (4)
C5	0.0227 (6)	0.0339 (7)	0.0350 (7)	0.0019 (5)	−0.0114 (5)	−0.0058 (6)
C9	0.0233 (6)	0.0362 (7)	0.0309 (7)	0.0014 (5)	−0.0117 (5)	−0.0051 (5)
C4	0.0239 (6)	0.0336 (7)	0.0302 (7)	0.0006 (5)	−0.0097 (5)	−0.0036 (5)
C8	0.0216 (6)	0.0345 (7)	0.0328 (7)	−0.0001 (5)	−0.0081 (5)	−0.0071 (5)
C1	0.0239 (6)	0.0391 (7)	0.0434 (8)	0.0009 (5)	−0.0134 (6)	−0.0057 (6)
C6	0.0264 (6)	0.0369 (7)	0.0354 (7)	0.0051 (5)	−0.0153 (6)	−0.0044 (6)
C2	0.0218 (6)	0.0427 (8)	0.0430 (8)	−0.0027 (5)	−0.0077 (6)	−0.0039 (6)
C7	0.0281 (7)	0.0336 (7)	0.0307 (7)	0.0020 (5)	−0.0093 (5)	−0.0024 (5)
C3	0.0247 (6)	0.0361 (7)	0.0355 (7)	−0.0012 (5)	−0.0057 (5)	−0.0057 (6)
C10	0.0278 (7)	0.0403 (8)	0.0332 (7)	0.0019 (6)	−0.0047 (5)	−0.0041 (6)
C11	0.0360 (8)	0.0560 (10)	0.0431 (8)	−0.0103 (7)	−0.0132 (7)	0.0023 (7)
C12	0.0441 (9)	0.0773 (12)	0.0404 (9)	−0.0070 (8)	−0.0160 (7)	0.0031 (8)
C13	0.0510 (10)	0.0644 (11)	0.0386 (9)	−0.0040 (8)	−0.0068 (7)	0.0091 (8)
C14	0.0588 (11)	0.0530 (10)	0.0482 (10)	−0.0184 (8)	−0.0038 (8)	0.0031 (8)
C15	0.0462 (9)	0.0517 (9)	0.0393 (8)	−0.0123 (7)	−0.0082 (7)	−0.0052 (7)
C16	0.0701 (13)	0.1072 (17)	0.0656 (12)	0.0106 (12)	−0.0457 (11)	−0.0277 (12)
C17	0.0703 (13)	0.0491 (10)	0.0732 (13)	0.0092 (9)	−0.0106 (10)	0.0160 (9)
C18	0.0378 (8)	0.0454 (9)	0.0718 (11)	−0.0098 (7)	−0.0173 (8)	−0.0089 (8)

Geometric parameters (Å, º) top

O3—C6	1.3753 (15)	C5—C6	1.4120 (19)
O3—C16	1.422 (2)	C5—C1	1.4757 (18)
O2—C1	1.2341 (16)	C9—C8	1.3798 (18)
O5—C8	1.3724 (15)	C9—C4	1.3992 (18)
O5—C18	1.4193 (19)	C8—C7	1.4024 (18)
C18—H22A	0.9600	C1—C2	1.438 (2)
C18—H22B	0.9600	C6—C7	1.3857 (19)
C18—H22C	0.9600	C2—C3	1.3430 (19)
C16—H27A	0.9600	C2—H8A	0.9300
C16—H27B	0.9600	C3—C10	1.4735 (19)
C16—H27C	0.9600	C10—C15	1.386 (2)
O6—C9	1.3552 (15)	C10—C11	1.393 (2)
O6—H8	0.8200	C15—C14	1.384 (2)
O4—C7	1.3687 (16)	C15—H21	0.9300
O4—C17	1.408 (2)	C12—C13	1.372 (3)
C17—H30A	0.9600	C12—C11	1.378 (2)
C17—H30B	0.9600	C12—H18	0.9300
C17—H30C	0.9600	C11—H17	0.9300
O1—C3	1.3599 (16)	C13—C14	1.380 (3)
O1—C4	1.3733 (16)	C13—H19	0.9300
C5—C4	1.4009 (17)	C14—H20	0.9300

C6—O3—C16	113.82 (13)	C9—C8—C7	121.45 (12)
C8—O5—C18	114.34 (11)	O2—C1—C2	121.77 (13)
O5—C18—H22A	109.5	O2—C1—C5	123.02 (13)
O5—C18—H22B	109.5	C2—C1—C5	115.18 (11)
H22A—C18—H22B	109.5	O3—C6—C7	118.28 (12)
O5—C18—H22C	109.5	O3—C6—C5	121.32 (12)
H22A—C18—H22C	109.5	C7—C6—C5	120.36 (12)
H22B—C18—H22C	109.5	C3—C2—C1	122.86 (12)
O3—C16—H27A	109.5	C3—C2—H8A	118.6
O3—C16—H27B	109.5	C1—C2—H8A	118.6
H27A—C16—H27B	109.5	O4—C7—C6	122.84 (12)
O3—C16—H27C	109.5	O4—C7—C8	117.18 (12)
H27A—C16—H27C	109.5	C6—C7—C8	119.84 (12)
H27B—C16—H27C	109.5	C2—C3—O1	121.83 (12)
C9—O6—H8	109.5	C2—C3—C10	126.44 (12)
C7—O4—C17	117.76 (13)	O1—C3—C10	111.69 (11)
O4—C17—H30A	109.5	C15—C10—C11	119.00 (14)
O4—C17—H30B	109.5	C15—C10—C3	120.60 (13)
H30A—C17—H30B	109.5	C11—C10—C3	120.40 (13)
O4—C17—H30C	109.5	C14—C15—C10	120.13 (15)
H30A—C17—H30C	109.5	C14—C15—H21	119.9
H30B—C17—H30C	109.5	C10—C15—H21	119.9
C3—O1—C4	119.21 (10)	C13—C12—C11	120.27 (16)
C4—C5—C6	117.91 (12)	C13—C12—H18	119.9
C4—C5—C1	117.68 (12)	C11—C12—H18	119.9
C6—C5—C1	124.41 (12)	C12—C11—C10	120.38 (15)
O6—C9—C8	123.53 (11)	C12—C11—H17	119.8
O6—C9—C4	118.48 (11)	C10—C11—H17	119.8
C8—C9—C4	117.98 (11)	C12—C13—C14	119.99 (15)
O1—C4—C9	114.47 (11)	C12—C13—H19	120.0
O1—C4—C5	123.14 (11)	C14—C13—H19	120.0
C9—C4—C5	122.39 (12)	C13—C14—C15	120.22 (16)
O5—C8—C9	117.81 (11)	C13—C14—H20	119.9
O5—C8—C7	120.68 (12)	C15—C14—H20	119.9

C3—O1—C4—C9	−178.49 (11)	C5—C1—C2—C3	3.3 (2)
C3—O1—C4—C5	2.30 (19)	C17—O4—C7—C6	60.8 (2)
O6—C9—C4—O1	2.27 (18)	C17—O4—C7—C8	−123.44 (17)
C8—C9—C4—O1	−176.89 (11)	O3—C6—C7—O4	−4.1 (2)
O6—C9—C4—C5	−178.52 (12)	C5—C6—C7—O4	178.13 (12)
C8—C9—C4—C5	2.3 (2)	O3—C6—C7—C8	−179.74 (12)
C6—C5—C4—O1	177.67 (12)	C5—C6—C7—C8	2.4 (2)
C1—C5—C4—O1	−1.7 (2)	O5—C8—C7—O4	−0.13 (19)
C6—C5—C4—C9	−1.5 (2)	C9—C8—C7—O4	−177.50 (12)
C1—C5—C4—C9	179.16 (12)	O5—C8—C7—C6	175.80 (12)
C18—O5—C8—C9	−94.47 (15)	C9—C8—C7—C6	−1.6 (2)
C18—O5—C8—C7	88.06 (16)	C1—C2—C3—O1	−2.9 (2)
O6—C9—C8—O5	2.7 (2)	C1—C2—C3—C10	174.87 (13)
C4—C9—C8—O5	−178.22 (11)	C4—O1—C3—C2	0.0 (2)
O6—C9—C8—C7	−179.89 (12)	C4—O1—C3—C10	−178.04 (11)
C4—C9—C8—C7	−0.8 (2)	C2—C3—C10—C15	34.3 (2)
C4—C5—C1—O2	176.96 (14)	O1—C3—C10—C15	−147.80 (14)
C6—C5—C1—O2	−2.4 (2)	C2—C3—C10—C11	−145.11 (16)
C4—C5—C1—C2	−0.99 (19)	O1—C3—C10—C11	32.83 (18)
C6—C5—C1—C2	179.69 (13)	C11—C10—C15—C14	−0.8 (2)
C16—O3—C6—C7	94.31 (17)	C3—C10—C15—C14	179.80 (15)
C16—O3—C6—C5	−87.89 (18)	C13—C12—C11—C10	1.2 (3)
C4—C5—C6—O3	−178.70 (12)	C15—C10—C11—C12	−0.3 (2)
C1—C5—C6—O3	0.6 (2)	C3—C10—C11—C12	179.07 (15)
C4—C5—C6—C7	−1.0 (2)	C11—C12—C13—C14	−0.9 (3)
C1—C5—C6—C7	178.37 (13)	C12—C13—C14—C15	−0.2 (3)
O2—C1—C2—C3	−174.72 (15)	C10—C15—C14—C13	1.1 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O6—H8···O5	0.82	2.35	2.770 (1)	113
O6—H8···O2ⁱ	0.82	1.94	2.727 (1)	160

Symmetry code: (i) x+1, y, z.

Experimental details

Crystal data
Chemical formula	C₁₈H₁₆O₆
M_r	328.32
Crystal system, space group	Triclinic, P1
Temperature (K)	294
a, b, c (Å)	8.4536 (2), 9.0878 (2), 10.7832 (3)
α, β, γ (°)	79.545 (2), 71.564 (1), 86.925 (2)
V (Å³)	772.85 (3)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.22 × 0.19 × 0.11

Data collection
Diffractometer	KappaCCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	20499, 3153, 2512
R_int	0.049
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.124, 1.07
No. of reflections	3153
No. of parameters	218
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.25, −0.24

Computer programs: COLLECT (Enraf–Nonius, 2000), DENZO and SCALEPACK (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O6—H8···O5	0.82	2.35	2.770 (1)	112.9
O6—H8···O2ⁱ	0.82	1.94	2.727 (1)	160.2

Symmetry code: (i) x+1, y, z.

Acknowledgements

The authors are grateful to Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) and Coordenação de Aperfeiçoamento de Pessoal de Ensino Superior (CAPES) for financial support.

References

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