2-(1H-Benzimidazol-1-yl)-1-phenyl­ethanone

Özel Güven, Ö.; Erdoğan, T.; Coles, S.J.; Hökelek, T.

doi:10.1107/S1600536808019107

organic compounds

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ISSN: 2056-9890

Volume 64| Part 7| July 2008| Page o1358

doi:10.1107/S1600536808019107

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2-(1H-Benzimidazol-1-yl)-1-phenylethanone

Özden Özel Güven,^a Taner Erdoğan,^a Simon J. Coles ^b and Tuncer Hökelek ^c ^*

^aZonguldak Karaelmas University, Department of Chemistry, 67100 Zonguldak, Turkey, ^bSouthampton University, Department of Chemistry, Southampton SO17 1BJ, England, and ^cHacettepe University, Department of Physics, 06800 Beytepe, Ankara, Turkey
^*Correspondence e-mail: merzifon@hacettepe.edu.tr

(Received 18 June 2008; accepted 24 June 2008; online 28 June 2008)

In the molecule of the title compound, C₁₅H₁₂N₂O, the planar benzimidazole system is oriented at a dihedral angle of 80.43 (5)° with respect to the phenyl ring. In the crystal structure, non-classical intermolecular C—H⋯N and C—H⋯O hydrogen bonds link the molecules into layers parallel to the ab plane.

Related literature

For general backgroud, see: Göker et al. (2002 ); Özden et al. (2004 ); Özel Güven et al. (2007a ,b ); Schar et al. (1976 ). For related literature, see: Peeters et al. (1997 ); Freer et al. (1986 ); Özel Güven et al. (2007 ).

Experimental

Crystal data

C₁₅H₁₂N₂O
M_r = 236.27
Monoclinic, P 2₁
a = 5.0475 (2) Å
b = 11.2319 (6) Å
c = 10.3517 (5) Å
β = 96.620 (3)°
V = 582.96 (5) Å³
Z = 2
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 120 (2) K
0.45 × 0.22 × 0.03 mm

Data collection

Bruker–Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2007 ) T_min = 0.962, T_max = 0.997
6918 measured reflections
2639 independent reflections
2265 reflections with I > 2σ(I)
R_int = 0.057

Refinement

R[F² > 2σ(F²)] = 0.047
wR(F²) = 0.119
S = 1.06
2639 reflections
212 parameters
1 restraint
All H-atom parameters refined
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C8—H81⋯N2ⁱ	0.95 (2)	2.43 (2)	3.355 (3)	165.2 (17)
C8—H82⋯O1ⁱⁱ	0.98 (2)	2.38 (2)	3.351 (3)	170.1 (17)
Symmetry codes: (i) $[-x+1, y+{\script{1\over 2}}, -z]$ ; (ii) x+1, y, z.

Data collection: COLLECT (Hooft, 1998 ); cell refinement: DENZO (Otwinowski & Minor, 1997 ) and COLLECT; data reduction: DENZO and COLLECT; 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 I, global. DOI: 10.1107/S1600536808019107/si2097sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808019107/si2097Isup2.hkl

checkCIF report

Comment top

Benzimidazoles have been shown to exhibit a large number of biological activities. Some of the substituted benzimidazole derivatives have highly potent antifungal (Göker et al., 2002) and antibacterial (Özden et al., 2004) activities. Recently, it has been reported that benzimidazole ring containing aryl ethers (Özel Güven et al., 2007a,b) similar to miconazole (Peeters et al., 1997) and econazole (Freer et al., 1986) structures have more antibacterial activities than antifungal activities (Schar et al., 1976). The crystal structure of oxime form of the benzimidazole substituted ketone has been reported previously (Özel Güven et al., 2007). We report herein the crystal structure of ketone, which is a starting material for biologically important molecules.

In the molecule of the title compound (Fig. 1) the bond lengths and angles are generally within normal ranges. The planar benzimidazole ring system is oriented with respect to the phenyl ring at a dihedral angle of 80.43 (5)°. Atoms C8 and C9 are -0.010 (2) Å and 0.044 (2) Å away from the ring planes of benzimidazole and phenyl, respectively. So, they are coplanar with the adjacent rings. The N1—C8—C9 [111.88 (15)°] and C8—C9—C10 [117.10 (15)°] bond angles are highly different from each other, while O1—C9—C8 [121.07 (16)°] and O1—C9—C10 [121.84 (17)°] bond angles are nearly equal. The N1—C1—N2 [114.25 (18)°], N2—C2—C7 [110.35 (17)°] and C2—C7—C6 [123.30 (18)°] bond angles are enlarged, while C5—C6—C7 [116.34 (19)°] bond angle is narrowed, probably due to the intermolecular C—H···N and C—H···O hydrogen bonds (Table 1).

In the crystal structure, non-classical intermolecular C—H···N and C—H···O hydrogen bonds (Table 1) link the molecules into layers parallel to the a,b plane (Fig. 2), in which they seem to be effective in the stabilization of the crystal structure.

Related literature top

For general backgroud, see: Göker et al. (2002); Özden et al. (2004); Özel Güven et al. (2007a,b); Schar et al. (1976). For related literature, see: Peeters et al. (1997); Freer et al. (1986); Özel Güven et al. (2007).

Experimental top

The title compound, was synthesized by the reaction of 2-bromo-1-phenyl- ethanone (Özel Güven et al., 2007a) with 1H-benzimidazole. A solution of 2-bromo-1-phenylethanone (4.00 g, 20.10 mmol) in dioxane-ether (8 ml) was added to an ice-cold solution of benzimidazole (11.87 g, 100.5 mmol) in methanol (20 ml) over 60 min under argon atmosphere. The reaction mixture was warmed to ambient temperature and stirred for an additional 18 h, diluted with water (20 ml), and then extracted with chloroform. Organic extract was dried over anhydrous sodium sulfate, concentrated under reduced pressure, and then chromatographed on neutral silica-gel column using chloroform-methanol as eluent. Crystals suitable for X-ray analysis were obtained by the recrystallization of the ketone from a mixture of hexane/ethyl acetate (1:2) (yield; 2.85 g, 60%).

Computing details top

Data collection: COLLECT (Hooft, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998); data reduction: DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998); 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. The molecular structure of the title molecule with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. A partial packing diagram of the title compound, viewed along the c axis. Hydrogen bonds are shown as dashed lines. H atoms not involved in hydrogen bonding have been omitted for clarity.

2-(1H-Benzimidazol-1-yl)-1-phenylethanone top

Crystal data top

C₁₅H₁₂N₂O	F(000) = 248
M_r = 236.27	D_x = 1.346 Mg m⁻³
Monoclinic, P2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 1379 reflections
a = 5.0475 (2) Å	θ = 2.9–27.5°
b = 11.2319 (6) Å	µ = 0.09 mm⁻¹
c = 10.3517 (5) Å	T = 120 K
β = 96.620 (3)°	Plate, colorless
V = 582.96 (5) Å³	0.45 × 0.22 × 0.03 mm
Z = 2

Data collection top

Bruker–Nonius Roper CCD camera on κ-goniostat diffractometer	2639 independent reflections
Radiation source: fine-focus sealed tube	2265 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.057
Detector resolution: 9.091 pixels mm^-1	θ_max = 27.5°, θ_min = 3.6°
ϕ and ω scans	h = −6→6
Absorption correction: multi-scan (SADABS; Sheldrick, 2007)	k = −14→14
T_min = 0.962, T_max = 0.997	l = −13→13
6918 measured reflections

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)] = 0.047	All H-atom parameters refined
wR(F²) = 0.119	w = 1/[σ²(F_o²) + (0.0651P)² + 0.019P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max < 0.001
2639 reflections	Δρ_max = 0.23 e Å⁻³
212 parameters	Δρ_min = −0.22 e Å⁻³
1 restraint	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.091 (14)

Crystal data top

C₁₅H₁₂N₂O	V = 582.96 (5) Å³
M_r = 236.27	Z = 2
Monoclinic, P2₁	Mo Kα radiation
a = 5.0475 (2) Å	µ = 0.09 mm⁻¹
b = 11.2319 (6) Å	T = 120 K
c = 10.3517 (5) Å	0.45 × 0.22 × 0.03 mm
β = 96.620 (3)°

Data collection top

Bruker–Nonius Roper CCD camera on κ-goniostat diffractometer	2639 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2007)	2265 reflections with I > 2σ(I)
T_min = 0.962, T_max = 0.997	R_int = 0.057
6918 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.047	1 restraint
wR(F²) = 0.119	All H-atom parameters refined
S = 1.06	Δρ_max = 0.23 e Å⁻³
2639 reflections	Δρ_min = −0.22 e Å⁻³
212 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
O1	0.0968 (3)	0.55671 (14)	0.26162 (13)	0.0288 (4)
N1	0.3784 (3)	0.56655 (14)	0.05460 (15)	0.0236 (4)
N2	0.3592 (4)	0.41520 (16)	−0.08838 (17)	0.0301 (4)
C1	0.4848 (4)	0.46224 (19)	0.0180 (2)	0.0265 (4)
H1	0.651 (6)	0.432 (3)	0.074 (3)	0.048 (7)*
C2	0.1553 (4)	0.49603 (17)	−0.12561 (19)	0.0251 (4)
C3	−0.0424 (4)	0.49415 (19)	−0.2318 (2)	0.0288 (5)
H3	−0.051 (5)	0.422 (2)	−0.291 (2)	0.034 (6)*
C4	−0.2249 (4)	0.5857 (2)	−0.2443 (2)	0.0315 (5)
H4	−0.366 (5)	0.584 (3)	−0.317 (3)	0.045 (7)*
C5	−0.2133 (4)	0.67987 (19)	−0.1537 (2)	0.0293 (5)
H5	−0.340 (4)	0.742 (2)	−0.168 (2)	0.020 (5)*
C6	−0.0171 (4)	0.68387 (18)	−0.0477 (2)	0.0258 (4)
H6	−0.013 (5)	0.753 (3)	0.011 (3)	0.048 (7)*
C7	0.1634 (4)	0.59090 (17)	−0.03658 (18)	0.0237 (4)
C8	0.4659 (4)	0.63860 (18)	0.16674 (18)	0.0241 (4)
H81	0.481 (4)	0.720 (2)	0.143 (2)	0.025 (5)*
H82	0.642 (4)	0.609 (2)	0.203 (2)	0.025 (5)*
C9	0.2788 (4)	0.62815 (17)	0.27150 (18)	0.0222 (4)
C10	0.3283 (4)	0.70936 (18)	0.38542 (18)	0.0226 (4)
C11	0.5216 (4)	0.79730 (19)	0.39188 (18)	0.0273 (5)
H11	0.646 (4)	0.805 (2)	0.326 (2)	0.024 (5)*
C12	0.5582 (4)	0.8738 (2)	0.4985 (2)	0.0310 (5)
H12	0.695 (5)	0.934 (2)	0.503 (2)	0.031 (6)*
C13	0.3975 (4)	0.8617 (2)	0.5977 (2)	0.0351 (5)
H13	0.420 (5)	0.920 (3)	0.678 (3)	0.047 (7)*
C14	0.2068 (5)	0.7743 (2)	0.5926 (2)	0.0352 (5)
H14	0.089 (6)	0.761 (3)	0.658 (3)	0.061 (9)*
C15	0.1691 (4)	0.69726 (19)	0.4872 (2)	0.0284 (5)
H15	0.036 (4)	0.636 (2)	0.481 (2)	0.025 (6)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0307 (7)	0.0341 (8)	0.0215 (7)	−0.0053 (6)	0.0026 (5)	0.0005 (6)
N1	0.0279 (8)	0.0236 (8)	0.0200 (8)	−0.0005 (7)	0.0049 (6)	−0.0003 (6)
N2	0.0377 (9)	0.0257 (8)	0.0282 (9)	−0.0016 (8)	0.0098 (7)	−0.0009 (7)
C1	0.0316 (10)	0.0239 (9)	0.0249 (10)	−0.0013 (8)	0.0071 (8)	0.0010 (8)
C2	0.0276 (9)	0.0245 (10)	0.0245 (10)	−0.0034 (8)	0.0085 (7)	−0.0015 (8)
C3	0.0341 (10)	0.0313 (11)	0.0219 (10)	−0.0098 (9)	0.0075 (8)	−0.0055 (8)
C4	0.0300 (11)	0.0417 (12)	0.0230 (10)	−0.0051 (9)	0.0034 (8)	0.0013 (8)
C5	0.0303 (10)	0.0336 (12)	0.0244 (10)	0.0019 (9)	0.0052 (8)	0.0009 (8)
C6	0.0297 (10)	0.0265 (10)	0.0222 (9)	0.0016 (8)	0.0072 (7)	−0.0015 (8)
C7	0.0271 (9)	0.0276 (10)	0.0170 (9)	−0.0050 (8)	0.0045 (7)	0.0006 (8)
C8	0.0269 (10)	0.0256 (11)	0.0200 (9)	−0.0007 (8)	0.0029 (8)	−0.0002 (8)
C9	0.0210 (9)	0.0241 (9)	0.0207 (9)	0.0012 (8)	−0.0003 (7)	0.0034 (7)
C10	0.0249 (9)	0.0246 (9)	0.0173 (9)	0.0043 (8)	−0.0022 (7)	0.0027 (7)
C11	0.0293 (10)	0.0311 (11)	0.0218 (10)	−0.0011 (9)	0.0041 (8)	0.0027 (8)
C12	0.0378 (11)	0.0294 (11)	0.0248 (10)	−0.0045 (10)	−0.0001 (9)	−0.0017 (8)
C13	0.0464 (13)	0.0341 (12)	0.0248 (11)	−0.0012 (10)	0.0043 (9)	−0.0040 (9)
C14	0.0414 (11)	0.0437 (13)	0.0222 (10)	−0.0004 (10)	0.0101 (9)	−0.0020 (9)
C15	0.0297 (10)	0.0311 (11)	0.0243 (10)	−0.0029 (9)	0.0032 (7)	0.0015 (8)

Geometric parameters (Å, º) top

O1—C9	1.215 (2)	C7—C2	1.406 (3)
N1—C1	1.361 (3)	C8—H81	0.95 (3)
N1—C7	1.381 (2)	C8—H82	0.98 (2)
N1—C8	1.442 (3)	C9—C8	1.522 (3)
N2—C1	1.317 (3)	C10—C9	1.489 (3)
N2—C2	1.393 (3)	C10—C15	1.403 (3)
C1—H1	1.02 (3)	C11—C10	1.384 (3)
C3—C2	1.398 (3)	C11—C12	1.394 (3)
C3—C4	1.377 (3)	C11—H11	0.99 (2)
C3—H3	1.01 (3)	C12—H12	0.96 (3)
C4—H4	0.98 (3)	C13—C12	1.386 (3)
C5—C4	1.410 (3)	C13—C14	1.371 (3)
C5—H5	0.95 (2)	C13—H13	1.06 (3)
C6—C5	1.391 (3)	C14—C15	1.389 (3)
C6—C7	1.382 (3)	C14—H14	0.96 (3)
C6—H6	0.99 (3)	C15—H15	0.96 (2)

C1—N1—C7	106.55 (16)	N1—C8—H81	111.1 (13)
C1—N1—C8	127.82 (17)	N1—C8—H82	107.2 (13)
C7—N1—C8	125.63 (16)	C9—C8—H81	109.4 (13)
C1—N2—C2	103.83 (17)	C9—C8—H82	108.0 (13)
N1—C1—H1	116.9 (16)	H81—C8—H82	109.1 (19)
N2—C1—N1	114.25 (18)	O1—C9—C8	121.07 (16)
N2—C1—H1	128.8 (16)	O1—C9—C10	121.84 (17)
N2—C2—C3	130.22 (18)	C10—C9—C8	117.10 (15)
N2—C2—C7	110.35 (17)	C11—C10—C9	121.91 (17)
C3—C2—C7	119.43 (18)	C11—C10—C15	119.61 (18)
C2—C3—H3	117.7 (14)	C15—C10—C9	118.47 (18)
C4—C3—C2	118.14 (19)	C10—C11—C12	120.42 (18)
C4—C3—H3	124.0 (14)	C10—C11—H11	122.1 (13)
C3—C4—C5	121.5 (2)	C12—C11—H11	117.4 (13)
C3—C4—H4	118.4 (17)	C13—C12—C11	119.4 (2)
C5—C4—H4	120.1 (17)	C13—C12—H12	120.8 (15)
C6—C5—C4	121.3 (2)	C11—C12—H12	119.8 (15)
C6—C5—H5	120.4 (13)	C12—C13—H13	120.3 (15)
C4—C5—H5	118.3 (13)	C14—C13—C12	120.7 (2)
C5—C6—H6	118.1 (15)	C14—C13—H13	119.0 (15)
C7—C6—C5	116.34 (19)	C13—C14—C15	120.5 (2)
C7—C6—H6	125.5 (15)	C13—C14—H14	125 (2)
N1—C7—C2	105.01 (16)	C15—C14—H14	115 (2)
N1—C7—C6	131.69 (17)	C10—C15—H15	118.6 (13)
C6—C7—C2	123.30 (18)	C14—C15—C10	119.4 (2)
N1—C8—C9	111.88 (15)	C14—C15—H15	122.0 (13)

C7—N1—C1—N2	−0.3 (2)	N1—C7—C2—N2	0.66 (19)
C8—N1—C1—N2	178.87 (18)	N1—C7—C2—C3	−179.80 (17)
C1—N1—C7—C2	−0.21 (18)	C6—C7—C2—N2	−179.13 (17)
C1—N1—C7—C6	179.6 (2)	C6—C7—C2—C3	0.4 (3)
C8—N1—C7—C2	−179.44 (17)	O1—C9—C8—N1	7.0 (2)
C8—N1—C7—C6	0.3 (3)	C10—C9—C8—N1	−172.76 (16)
C1—N1—C8—C9	−105.9 (2)	C11—C10—C9—O1	−174.63 (18)
C7—N1—C8—C9	73.2 (2)	C11—C10—C9—C8	5.1 (3)
C2—N2—C1—N1	0.7 (2)	C15—C10—C9—O1	3.9 (3)
C1—N2—C2—C3	179.7 (2)	C15—C10—C9—C8	−176.38 (17)
C1—N2—C2—C7	−0.8 (2)	C9—C10—C15—C14	−178.14 (19)
C4—C3—C2—N2	178.8 (2)	C11—C10—C15—C14	0.4 (3)
C4—C3—C2—C7	−0.7 (3)	C10—C11—C12—C13	−0.6 (3)
C2—C3—C4—C5	0.6 (3)	C12—C11—C10—C9	178.37 (18)
C6—C5—C4—C3	−0.2 (3)	C12—C11—C10—C15	−0.1 (3)
C5—C6—C7—N1	−179.7 (2)	C14—C13—C12—C11	1.1 (3)
C5—C6—C7—C2	0.0 (3)	C12—C13—C14—C15	−0.8 (3)
C7—C6—C5—C4	−0.1 (3)	C13—C14—C15—C10	0.0 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H81···N2ⁱ	0.95 (2)	2.43 (2)	3.355 (3)	165.2 (17)
C8—H82···O1ⁱⁱ	0.98 (2)	2.38 (2)	3.351 (3)	170.1 (17)

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

Experimental details

Crystal data
Chemical formula	C₁₅H₁₂N₂O
M_r	236.27
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	120
a, b, c (Å)	5.0475 (2), 11.2319 (6), 10.3517 (5)
β (°)	96.620 (3)
V (Å³)	582.96 (5)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.45 × 0.22 × 0.03

Data collection
Diffractometer	Bruker–Nonius Roper CCD camera on κ-goniostat diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2007)
T_min, T_max	0.962, 0.997
No. of measured, independent and observed [I > 2σ(I)] reflections	6918, 2639, 2265
R_int	0.057
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.047, 0.119, 1.06
No. of reflections	2639
No. of parameters	212
No. of restraints	1
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.22

Computer programs: , DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998), 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
C8—H81···N2ⁱ	0.95 (2)	2.43 (2)	3.355 (3)	165.2 (17)
C8—H82···O1ⁱⁱ	0.98 (2)	2.38 (2)	3.351 (3)	170.1 (17)

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

Acknowledgements

The authors acknowledge Zonguldak Karaelmas University Research Fund (grant No: 2004–13-02–16).

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