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ISSN: 2056-9890

Ethyl (E)-3-(6-methyl-4-oxo-4H-chromen-3-yl)prop-2-enoate

aH.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan
*Correspondence e-mail: dr.sammer.yousuf@gmail.com

(Received 30 August 2012; accepted 8 September 2012; online 19 September 2012)

In the title compound, C15H14O4, the chromone ring system is close to being planar [maximum deviation = 0.015 (2) Å]. The double bond of the ethyl prop-2-enoate chain adopts an E conformation and an intra­molecular C—H⋯O hydrogen bond generates an S6 ring. In the crystal, inversion dimers linked by pairs of C—H⋯O hydrogen bonds generate R22(14) loops. Weak ππ inter­actions [centroid–centroid distance = 3.8493 (12) Å] also occur.

Related literature

For the biological activity of chromones, see: Patel et al. (2011[Patel, M. C., Nilesh, N. G. & Rajani, D. P. (2011). Der Pharma Chem. 3, 422-432.]); Khan et al. (2010[Khan, K. M., Ambreen, N., Mughal, U. R., Jalil, S., Perveen, S. & Choudhary, M. I. (2010). Eur. J. Med. Chem. 45, 4058-4064.]); Gautam et al. (2010[Gautam, R., Srivastava, A., Jachak, M. S. & Saklani, A. (2010). Fitoterapia, 81, 45-49.]). For a related structure, see: Wang & Kong (2007[Wang, X.-B. & Kong, L.-Y. (2007). Acta Cryst. E63, o4340.]).

[Scheme 1]

Experimental

Crystal data
  • C15H14O4

  • Mr = 258.26

  • Monoclinic, P 21 /c

  • a = 13.8663 (12) Å

  • b = 12.3512 (10) Å

  • c = 7.6947 (6) Å

  • β = 96.390 (2)°

  • V = 1309.65 (19) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 298 K

  • 0.34 × 0.25 × 0.16 mm

Data collection
  • Bruker SMART APEX CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2000[Bruker (2000). SADABS, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.968, Tmax = 0.985

  • 7621 measured reflections

  • 2431 independent reflections

  • 1650 reflections with I > 2σ(I)

  • Rint = 0.027

Refinement
  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.142

  • S = 1.04

  • 2431 reflections

  • 175 parameters

  • H-atom parameters constrained

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.15 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C11—H11A⋯O2 0.93 2.28 2.908 (2) 124
C9—H9A⋯O3i 0.93 2.37 3.276 (3) 164
Symmetry code: (i) -x+1, -y+1, -z.

Data collection: SMART (Bruker, 2000[Bruker (2000). SADABS, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2000[Bruker (2000). SADABS, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL and PARST (Nardelli, 1995[Nardelli, M. (1995). J. Appl. Cryst. 28, 659.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Chromone is a group of naturally occurring oxygen containing heterocyclic compounds having a benzene ring fused with pyran ring. They are widely distributed in plant kingdom and form the basic nucleus of important compounds such as anthocyanin and flavonoids. The chromone moiety forms an important component of pharmacophores of a number of biologically active molecules of synthetic as well as natural origin and therefore responsible for various biological activities (e.g. Patel et al. (2011); Gautam et al. (2010); Khan et al. (2010). The title compound is a chromone derivative obtained as a part of our ongoing project to synthesize libraries of chromone derivatives in order to study their different biological activities. The structure of title compound (Fig. 1) is composed of almost planner chromone moiety (O1/C1–C9) with maximum deviation of 0.015 (2) Å for C7 atom from the root mean square plane. The C11–C12 (1.462 (3) Å) olefinic bond of ethyl prop-2-enoate chain (O3–O4/C10–C14) attached to chromone moiety adopt an E configuartion. The shorter bond lengths of C11–C12 = 1.462 (3) Å than the expected C–C single bond length is due to the conjugation effects of the olefinc bond (C11–C12, 1.462 (3) Å) with carbonyl carbon (O3/C12) of ethyl prop-2-enoate chain (O3–O4/C10–C14). The bond lengths and angle were found to be similar as in structurally realted compound (Wang & Kong, 2007). The E conformation of olefinic bound further stabilized by an intramolecular C11–C11A···O2 intramolecular hydrogen bond. In the crystal inversion-related molecules are consolidated by C9–C9A···O3 hydrogen bond and found stacked along the a-axis. The crystal structure also features weak ππ interaction between pyrane (Cg(1)= O1/C6–C9) and benzene (Cg(2)= C1–C6) of chromone moeity ((Cg(1)to Cg(2) distance = 3.8493 (12) Å;X,1/2-Y,-1/2+Z)

Related literature top

For the biological activity of chromones, see: Patel et al. (2011); Khan et al. (2010); Gautam et al. (2010). For a related structure, see: Wang & Kong (2007).

Experimental top

A mixture of 3-formyl chromone (10 mmol) and malonic acid (20 mmol), using pyridine (15 ml) as solvent was refluxed in 500 mL round-bottomed flask for 30–45 minutes with vigorous stirring. After completion of reaction (monitored by TLC), the reaction mixture was cooled to room temperature, acidified by concntrated hydrochloric acid (pH 1.0) and stirred again for 30 minutes at room temprature. The yellow colored solid (1.02 g) obtained was filtered and washed with water. The crude residue was dried, dissolved in ethanol (50 ml) along with few drops of H2SO4 and refluxed for 24 h (progress of the reaction was monitored by TLC). After completion of reaction the solvent was evaporated under vacuum followed by addition of saturated solution of NaHCO3 and extracted with ethyl acetate, washed with water. The organic phase was dried over Na2SO4. The solvent was evaporated under reduced pressure to obtain crude product which was further recrystallized in ethanol to obtain yellow blocks in 82% yield (0.94 g).

Refinement top

H atoms on Methyl, methylene and methine were positioned geometrically with C—H = 0.96 Å (CH3), 0.97 Å (CH3) and 0.93 Å (CH) and constrained to ride on their parent atoms with Uiso(H)= 1.5Ueq(CH3) and 1.2Ueq(CH2, CH).

Structure description top

Chromone is a group of naturally occurring oxygen containing heterocyclic compounds having a benzene ring fused with pyran ring. They are widely distributed in plant kingdom and form the basic nucleus of important compounds such as anthocyanin and flavonoids. The chromone moiety forms an important component of pharmacophores of a number of biologically active molecules of synthetic as well as natural origin and therefore responsible for various biological activities (e.g. Patel et al. (2011); Gautam et al. (2010); Khan et al. (2010). The title compound is a chromone derivative obtained as a part of our ongoing project to synthesize libraries of chromone derivatives in order to study their different biological activities. The structure of title compound (Fig. 1) is composed of almost planner chromone moiety (O1/C1–C9) with maximum deviation of 0.015 (2) Å for C7 atom from the root mean square plane. The C11–C12 (1.462 (3) Å) olefinic bond of ethyl prop-2-enoate chain (O3–O4/C10–C14) attached to chromone moiety adopt an E configuartion. The shorter bond lengths of C11–C12 = 1.462 (3) Å than the expected C–C single bond length is due to the conjugation effects of the olefinc bond (C11–C12, 1.462 (3) Å) with carbonyl carbon (O3/C12) of ethyl prop-2-enoate chain (O3–O4/C10–C14). The bond lengths and angle were found to be similar as in structurally realted compound (Wang & Kong, 2007). The E conformation of olefinic bound further stabilized by an intramolecular C11–C11A···O2 intramolecular hydrogen bond. In the crystal inversion-related molecules are consolidated by C9–C9A···O3 hydrogen bond and found stacked along the a-axis. The crystal structure also features weak ππ interaction between pyrane (Cg(1)= O1/C6–C9) and benzene (Cg(2)= C1–C6) of chromone moeity ((Cg(1)to Cg(2) distance = 3.8493 (12) Å;X,1/2-Y,-1/2+Z)

For the biological activity of chromones, see: Patel et al. (2011); Khan et al. (2010); Gautam et al. (2010). For a related structure, see: Wang & Kong (2007).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); 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, PARST (Nardelli, 1995) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) with displacement ellipsoids drawn at 30% probability level.
[Figure 2] Fig. 2. The crystal packing of the title compound I.
Ethyl (E)-3-(6-methyl-4-oxo-4H-chromen-3-yl)prop-2-enoate top
Crystal data top
C15H14O4F(000) = 544
Mr = 258.26Dx = 1.310 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 13.8663 (12) ÅCell parameters from 1626 reflections
b = 12.3512 (10) Åθ = 3.0–23.3°
c = 7.6947 (6) ŵ = 0.10 mm1
β = 96.390 (2)°T = 298 K
V = 1309.65 (19) Å3Block, colourless
Z = 40.34 × 0.25 × 0.16 mm
Data collection top
Bruker SMART APEX CCD
diffractometer
2431 independent reflections
Radiation source: fine-focus sealed tube1650 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.027
ω scanθmax = 25.5°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
h = 1616
Tmin = 0.968, Tmax = 0.985k = 1414
7621 measured reflectionsl = 99
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.048H-atom parameters constrained
wR(F2) = 0.142 w = 1/[σ2(Fo2) + (0.0754P)2 + 0.0649P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max < 0.001
2431 reflectionsΔρmax = 0.17 e Å3
175 parametersΔρmin = 0.15 e Å3
0 restraintsExtinction correction: SHELXTL (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0028 (16)
Crystal data top
C15H14O4V = 1309.65 (19) Å3
Mr = 258.26Z = 4
Monoclinic, P21/cMo Kα radiation
a = 13.8663 (12) ŵ = 0.10 mm1
b = 12.3512 (10) ÅT = 298 K
c = 7.6947 (6) Å0.34 × 0.25 × 0.16 mm
β = 96.390 (2)°
Data collection top
Bruker SMART APEX CCD
diffractometer
2431 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
1650 reflections with I > 2σ(I)
Tmin = 0.968, Tmax = 0.985Rint = 0.027
7621 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0480 restraints
wR(F2) = 0.142H-atom parameters constrained
S = 1.04Δρmax = 0.17 e Å3
2431 reflectionsΔρmin = 0.15 e Å3
175 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
xyzUiso*/Ueq
O10.74141 (9)0.20992 (10)0.17694 (19)0.0713 (4)
O20.85161 (10)0.49847 (11)0.3624 (2)0.0786 (5)
O30.51893 (10)0.66244 (12)0.0798 (2)0.0880 (5)
O40.63447 (9)0.77677 (10)0.18750 (18)0.0677 (4)
C10.83451 (14)0.21480 (15)0.2624 (3)0.0597 (5)
C20.88511 (15)0.11889 (17)0.2813 (3)0.0715 (6)
H2A0.85660.05420.24050.086*
C30.97837 (16)0.12068 (19)0.3615 (3)0.0731 (6)
H3A1.01330.05630.37240.088*
C41.02265 (14)0.21586 (18)0.4273 (3)0.0653 (6)
C50.97015 (13)0.31040 (17)0.4062 (2)0.0614 (5)
H5A0.99870.37490.44760.074*
C60.87513 (12)0.31198 (15)0.3241 (2)0.0540 (5)
C70.81876 (12)0.41241 (16)0.3029 (2)0.0570 (5)
C80.72174 (12)0.40105 (15)0.2076 (2)0.0537 (5)
C90.69141 (14)0.30212 (16)0.1524 (3)0.0637 (5)
H9A0.62980.29750.09130.076*
C100.65611 (13)0.49171 (15)0.1662 (2)0.0571 (5)
H10A0.59640.47500.10470.069*
C110.67129 (13)0.59483 (16)0.2054 (3)0.0594 (5)
H11A0.72920.61510.26970.071*
C120.59924 (13)0.67789 (15)0.1500 (3)0.0595 (5)
C130.57176 (15)0.86723 (17)0.1372 (3)0.0764 (6)
H13A0.51680.86770.20490.092*
H13B0.54760.86240.01420.092*
C140.63063 (19)0.96782 (18)0.1716 (3)0.0915 (8)
H14A0.58951.03000.15110.137*
H14B0.68070.97000.09500.137*
H14C0.65960.96800.29090.137*
C151.12484 (15)0.2147 (2)0.5173 (3)0.0877 (7)
H15A1.15560.28270.49850.132*
H15B1.16060.15720.47030.132*
H15C1.12340.20350.64040.132*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0564 (9)0.0616 (9)0.0918 (11)0.0011 (6)0.0101 (7)0.0061 (7)
O20.0551 (8)0.0610 (9)0.1124 (12)0.0051 (6)0.0225 (8)0.0025 (8)
O30.0525 (9)0.0756 (10)0.1274 (14)0.0032 (7)0.0270 (9)0.0082 (9)
O40.0541 (8)0.0600 (9)0.0857 (10)0.0022 (6)0.0068 (7)0.0026 (7)
C10.0510 (11)0.0680 (13)0.0589 (12)0.0022 (9)0.0009 (9)0.0014 (10)
C20.0715 (14)0.0655 (13)0.0760 (14)0.0070 (10)0.0019 (11)0.0045 (11)
C30.0705 (14)0.0801 (15)0.0680 (14)0.0231 (11)0.0049 (11)0.0014 (11)
C40.0547 (12)0.0860 (15)0.0544 (12)0.0135 (10)0.0027 (9)0.0025 (10)
C50.0481 (11)0.0766 (14)0.0585 (12)0.0038 (9)0.0016 (9)0.0031 (10)
C60.0450 (10)0.0643 (12)0.0521 (11)0.0008 (8)0.0023 (8)0.0018 (9)
C70.0440 (10)0.0626 (12)0.0628 (12)0.0046 (9)0.0012 (9)0.0042 (10)
C80.0434 (10)0.0589 (11)0.0573 (11)0.0043 (8)0.0004 (8)0.0041 (9)
C90.0471 (11)0.0678 (13)0.0732 (14)0.0010 (9)0.0067 (10)0.0017 (10)
C100.0416 (10)0.0668 (13)0.0611 (12)0.0055 (8)0.0028 (8)0.0088 (9)
C110.0452 (10)0.0651 (13)0.0651 (12)0.0041 (9)0.0057 (9)0.0069 (10)
C120.0444 (11)0.0650 (13)0.0669 (13)0.0038 (9)0.0036 (9)0.0065 (10)
C130.0689 (14)0.0685 (14)0.0901 (16)0.0141 (10)0.0014 (12)0.0090 (11)
C140.117 (2)0.0648 (14)0.0893 (17)0.0040 (13)0.0039 (15)0.0030 (12)
C150.0587 (13)0.118 (2)0.0827 (16)0.0251 (13)0.0066 (11)0.0078 (14)
Geometric parameters (Å, º) top
O1—C91.336 (2)C7—C81.465 (2)
O1—C11.383 (2)C8—C91.346 (3)
O2—C71.225 (2)C8—C101.456 (2)
O3—C121.198 (2)C9—H9A0.9300
O4—C121.335 (2)C10—C111.320 (3)
O4—C131.442 (2)C10—H10A0.9300
C1—C21.376 (3)C11—C121.462 (3)
C1—C61.387 (3)C11—H11A0.9300
C2—C31.370 (3)C13—C141.494 (3)
C2—H2A0.9300C13—H13A0.9700
C3—C41.395 (3)C13—H13B0.9700
C3—H3A0.9300C14—H14A0.9600
C4—C51.376 (3)C14—H14B0.9600
C4—C151.506 (3)C14—H14C0.9600
C5—C61.396 (3)C15—H15A0.9600
C5—H5A0.9300C15—H15B0.9600
C6—C71.466 (3)C15—H15C0.9600
C9—O1—C1118.19 (15)C8—C9—H9A116.9
C12—O4—C13117.10 (15)C11—C10—C8127.74 (18)
C2—C1—O1116.79 (18)C11—C10—H10A116.1
C2—C1—C6121.72 (19)C8—C10—H10A116.1
O1—C1—C6121.49 (16)C10—C11—C12121.59 (18)
C3—C2—C1118.6 (2)C10—C11—H11A119.2
C3—C2—H2A120.7C12—C11—H11A119.2
C1—C2—H2A120.7O3—C12—O4122.87 (18)
C2—C3—C4122.18 (19)O3—C12—C11126.20 (18)
C2—C3—H3A118.9O4—C12—C11110.92 (16)
C4—C3—H3A118.9O4—C13—C14107.19 (18)
C5—C4—C3117.80 (19)O4—C13—H13A110.3
C5—C4—C15121.4 (2)C14—C13—H13A110.3
C3—C4—C15120.81 (19)O4—C13—H13B110.3
C4—C5—C6121.70 (19)C14—C13—H13B110.3
C4—C5—H5A119.1H13A—C13—H13B108.5
C6—C5—H5A119.1C13—C14—H14A109.5
C1—C6—C5118.00 (17)C13—C14—H14B109.5
C1—C6—C7120.19 (17)H14A—C14—H14B109.5
C5—C6—C7121.81 (17)C13—C14—H14C109.5
O2—C7—C8123.54 (17)H14A—C14—H14C109.5
O2—C7—C6121.42 (16)H14B—C14—H14C109.5
C8—C7—C6115.04 (17)C4—C15—H15A109.5
C9—C8—C10117.61 (16)C4—C15—H15B109.5
C9—C8—C7118.83 (17)H15A—C15—H15B109.5
C10—C8—C7123.55 (16)C4—C15—H15C109.5
O1—C9—C8126.19 (18)H15A—C15—H15C109.5
O1—C9—H9A116.9H15B—C15—H15C109.5
C9—O1—C1—C2178.25 (17)C1—C6—C7—C82.5 (3)
C9—O1—C1—C61.1 (3)C5—C6—C7—C8177.57 (16)
O1—C1—C2—C3178.48 (17)O2—C7—C8—C9177.91 (19)
C6—C1—C2—C30.8 (3)C6—C7—C8—C91.7 (2)
C1—C2—C3—C41.3 (3)O2—C7—C8—C103.2 (3)
C2—C3—C4—C51.4 (3)C6—C7—C8—C10177.23 (16)
C2—C3—C4—C15179.04 (19)C1—O1—C9—C82.1 (3)
C3—C4—C5—C60.9 (3)C10—C8—C9—O1179.58 (17)
C15—C4—C5—C6179.49 (19)C7—C8—C9—O10.6 (3)
C2—C1—C6—C50.4 (3)C9—C8—C10—C11179.17 (19)
O1—C1—C6—C5178.87 (16)C7—C8—C10—C110.2 (3)
C2—C1—C6—C7179.49 (17)C8—C10—C11—C12178.09 (17)
O1—C1—C6—C71.2 (3)C13—O4—C12—O31.0 (3)
C4—C5—C6—C10.5 (3)C13—O4—C12—C11178.89 (16)
C4—C5—C6—C7179.43 (17)C10—C11—C12—O36.7 (3)
C1—C6—C7—O2177.08 (18)C10—C11—C12—O4173.18 (17)
C5—C6—C7—O22.8 (3)C12—O4—C13—C14172.99 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11A···O20.932.282.908 (2)124
C9—H9A···O3i0.932.373.276 (3)164
Symmetry code: (i) x+1, y+1, z.

Experimental details

Crystal data
Chemical formulaC15H14O4
Mr258.26
Crystal system, space groupMonoclinic, P21/c
Temperature (K)298
a, b, c (Å)13.8663 (12), 12.3512 (10), 7.6947 (6)
β (°) 96.390 (2)
V3)1309.65 (19)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.34 × 0.25 × 0.16
Data collection
DiffractometerBruker SMART APEX CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2000)
Tmin, Tmax0.968, 0.985
No. of measured, independent and
observed [I > 2σ(I)] reflections
7621, 2431, 1650
Rint0.027
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.142, 1.04
No. of reflections2431
No. of parameters175
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.17, 0.15

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), SHELXTL (Sheldrick, 2008, PARST (Nardelli, 1995) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11A···O20.932.282.908 (2)124
C9—H9A···O3i0.932.373.276 (3)164
Symmetry code: (i) x+1, y+1, z.
 

Acknowledgements

The authors are thankful to OPCW, Netherlands, and the Higher Education Commission (HEC) Pakistan (project No. 1910) for their financial support.

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