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ISSN: 2056-9890

6,6,9a-Tri­methyl-5,5a,6,7,8,9,9a,9b-octa­hydro­naphtho[1,2-c]furan-1(3H)-one

aDepartamento de Química, Facultad de Ciencias Básicas, Universidad de Antofagasta, Casilla 170, Antofagasta, Chile, bInstituto de Bio-Orgánica 'Antonio González', Universidad de La Laguna, Astrofísico Francisco Sánchez No. 2, La Laguna, Tenerife, Spain, cDepartamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad de Concepción, Casilla 160-C, Concepción, Chile, and dLaboratorio de Fitoquímica, Facultad de Ciencias Biológicas, Universidad de Concepción y Centro de Investigación de Ecosistemas de la Patagonia (CIEP), Bilbao 449, Coyhaique, Chile
*Correspondence e-mail: ivanbritob@yahoo.com

(Received 4 March 2008; accepted 18 March 2008; online 29 March 2008)

In the crystal structure of the title compound, C15H22O2, the cyclo­hexene and cyclo­hexane rings adopt half-boat and chair conformations, respectively, and the lactone ring is in an envelope conformation.

Related literature

For related literature, see: Almeida et al. (2001[Almeida, A. T., Lacerda, R. & Kloos, H. (2001). Mem. Inst. Oswaldo Cruz, pp. 831-833.]); Appel et al. (1963[Appel, H. H., Bond, R. P. M. & Overton, K. H. (1963). Tetrahedron, 19, 635-641.]); Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]); Cruz et al. (1973[Cruz, A., Silva, M. & Sammmes, P. G. (1973). Phytochemistry, 12, 2549-2550.]); Harinantenaina et al. (2007[Harinantenaina, L., Asakawa, Y. & De Clercq, E. (2007). J. Nat. Prod. 70, 277-282.]); Sierra et al. (1986[Sierra, J., López, J. & Cortés, M. (1986). Phytochemistry, 25, 253-254.]).

[Scheme 1]

Experimental

Crystal data
  • C15H22O2

  • Mr = 234.33

  • Orthorhombic, P 21 21 21

  • a = 7.4031 (2) Å

  • b = 7.9250 (2) Å

  • c = 22.9973 (8) Å

  • V = 1349.24 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.07 mm−1

  • T = 298 (2) K

  • 0.14 × 0.12 × 0.08 mm

Data collection
  • Nonius KappaCCD area-detector diffractometer

  • Absorption correction: none

  • 4453 measured reflections

  • 1790 independent reflections

  • 1645 reflections with I > 2σ(I)

  • Rint = 0.066

Refinement
  • R[F2 > 2σ(F2)] = 0.061

  • wR(F2) = 0.167

  • S = 1.18

  • 1790 reflections

  • 163 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.19 e Å−3

Data collection: COLLECT (Nonius, 1998[Nonius (1998). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO–SMN (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO–SMN; program(s) used to solve structure: SIR97 (Altomare et al., 1999[Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115-119.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

Drimys winteri J.R. Forst is a plant used in folk medicine of many Latinoamerican countries. In Chile, Drimys winteri (canelo) is used by the indigenous Mapuche in the treatment of several stomachal diseases, ulcers and hemorrhages (Almeida et al., 2001). Chemical studies has shown the presence of a variety of sesquiterpenes with drimano skeleton (Appel et al., 1963) and flavonoids. Some of these compounds have shown significant antibacterial, antifungi, antitumor and insecticide properties (Cruz et al., 1973; Sierra et al., 1986). The extract of Drimys winteri leaves afforded Cinnamolide and Drimenin two lactones with drimano skeleton. The title compound (I) is a positional isomer of Cinnamolide [IUPAC name: 6,6,9a-trimethyl-5,5a,6,7,8,9,9a,9 b-octahydronaphtho [1,2-c]furan-3(1H)-one] (CSD refcode NIDJUG; Harinantenaina et al., 2007).In order to ascertain the structure and secure the assignment of the stereochemistry of (I) an X-ray analysis was performed but the absolute configuration was not determined by this analysis. The structure consists of a drimane skeleton and the methyl group at C9a is α -oriented. The cyclohexene ring (A) and cyclohexane ring (B) is in a half-boat and a chair conformation, respectively [QT = 0.526 (3) Å ϕ2 = 316.5 (4) °, q2 = 0.413 (3)Å for ring A; QT = 0.545 (3) Å, ϕ2 = 160 (4)°, q2 = 0.052 (4) Å for ring B], and the lactone ring is in an envelope conformation [q2=0.233 (3) Å, ϕ2 = 284.5 (7)°] (Cremer & Pople, 1975). The A and B rings are trans-fused.

Related literature top

For related literature, see: Almeida et al. (2001); Appel et al. (1963); Cremer & Pople (1975); Cruz et al. (1973); Harinantenaina et al. (2007); Sierra et al. (1986).

Experimental top

Drimys winteri was collected from the Estuary of Reloncaví, Xth° Región, Chile in November 2005. Two kilograms of bark was extracted in dichloromethane and concentrated by rotavapor to yield 180 g. 30 grams of crude extract was subjected to flash chromatography on Silicagel G, 70–200 mesh with hexane–ethyl-acetate mixtures of increasing polarity as elution solvents. Pure components were obtained by further chromatography on silicagel of the fraction 10% hexane–ethyl-acetate (11 g). Recrystallization from methanol,at room temperature afforded colourless crystals of drimenin (0.02 g) suitable for X-ray difracction analysis. NMR spectra (1H-RMN, 13C-RMN, DEPT and 1H-1H COSY) were obtained on a Bruker AC 250P multinuclear spectrometer, in DCCl3 with TMS as internal standard. Drimenin(C15H22O2); Colorless crystals, mp 95 - 97°C. 1H-RMN (250 MHz) δ(p.p.m.); 0.88(3H, s), 0.90 (3H, s), 0.92 (3H, s), 1.15–1.30 (2H, m), 1.35 (1H, dd, J=3.4, 5.0, 13 Hz), 2.77 (1H, br s), 4.65 (2H, m), 5.73 (1H, br s). 13C-RMN δ(p.p.m.) 175.3 (s); 121.1 (d); 129.8 (s); 69.8 (t); 53.6 (d); 49.6 (d); 42.3 (t); 38.4 (t); 34.3 (s); 33.0 (q); 31.1 (s); 23.3 (t); 21.4 (q); 18.3 (t); 13.9 (q).

Refinement top

The H atom bonded to C4 was found in difference maps and was freely refined. All other H atoms were positioned with idealized geometry (C—H = 0.96–0.98 Å) and were refined using a riding model, with Uiso(H) = 1.2Ueq(C) (1.5Ueq for methyl H atoms) of the carrier atom. In the absence of any significant anomalous scattering, Friedel equivalents were merged prior to the final refinements, and the absolute structure was not determined.

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: DENZO–SMN (Otwinowski & Minor, 1997); data reduction: DENZO–SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. A view of the molecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.
6,6,9a-Trimethyl-5,5a,6,7,8,9,9a,9b-octahydronaphtho[1,2-c]furan- 1(3H)-one top
Crystal data top
C15H22O2F(000) = 512
Mr = 234.33Dx = 1.154 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 4453 reflections
a = 7.4031 (2) Åθ = 2.7–27.5°
b = 7.9250 (2) ŵ = 0.07 mm1
c = 22.9973 (8) ÅT = 298 K
V = 1349.24 (7) Å3Prism, colourless
Z = 40.14 × 0.12 × 0.08 mm
Data collection top
Nonius KappaCCD area-detector
diffractometer
1645 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.066
Graphite monochromatorθmax = 27.5°, θmin = 2.7°
ϕ scans, and ω scans with κ offsetsh = 99
4453 measured reflectionsk = 1010
1790 independent reflectionsl = 2929
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.061 w = 1/[σ2(Fo2) + (0.0906P)2 + 0.1776P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.167(Δ/σ)max = 0.001
S = 1.18Δρmax = 0.23 e Å3
1790 reflectionsΔρmin = 0.19 e Å3
163 parameters
Crystal data top
C15H22O2V = 1349.24 (7) Å3
Mr = 234.33Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 7.4031 (2) ŵ = 0.07 mm1
b = 7.9250 (2) ÅT = 298 K
c = 22.9973 (8) Å0.14 × 0.12 × 0.08 mm
Data collection top
Nonius KappaCCD area-detector
diffractometer
1645 reflections with I > 2σ(I)
4453 measured reflectionsRint = 0.066
1790 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0610 restraints
wR(F2) = 0.167H atoms treated by a mixture of independent and constrained refinement
S = 1.18Δρmax = 0.23 e Å3
1790 reflectionsΔρmin = 0.19 e Å3
163 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
O10.8222 (4)0.4735 (2)0.79867 (11)0.0726 (8)
O20.6477 (3)0.2766 (3)0.76017 (10)0.0656 (7)
C10.7967 (4)0.3267 (3)0.78912 (12)0.0513 (7)
C30.6436 (5)0.0949 (4)0.75322 (14)0.0609 (8)
H3A0.67140.06320.71350.077 (3)*
H3B0.52610.04990.76350.077 (3)*
C3A0.7862 (4)0.0326 (3)0.79414 (10)0.0427 (6)
C40.7941 (4)0.1115 (3)0.82241 (13)0.0537 (7)
H40.712 (4)0.196 (4)0.8180 (12)0.052 (8)*
C50.9382 (5)0.1455 (4)0.86662 (14)0.0607 (8)
H5A0.99380.25350.8580.077 (3)*
H5B0.88250.15390.90470.077 (3)*
C5A1.0857 (4)0.0101 (3)0.86874 (10)0.0400 (5)
H5A11.15460.02610.83280.077 (3)*
C61.2257 (4)0.0397 (4)0.91848 (12)0.0533 (7)
C71.3670 (4)0.1013 (5)0.91648 (15)0.0648 (8)
H7A1.44510.09060.95010.077 (3)*
H7B1.44110.0860.88210.077 (3)*
C81.2894 (5)0.2776 (5)0.91553 (17)0.0701 (9)
H8A1.38680.35920.91310.077 (3)*
H8B1.22340.29820.95130.077 (3)*
C91.1637 (4)0.2991 (4)0.86386 (14)0.0573 (7)
H9A1.23260.28570.82830.077 (3)*
H9B1.11480.41260.86420.077 (3)*
C9A1.0067 (3)0.1719 (3)0.86379 (10)0.0383 (5)
C9B0.9142 (3)0.1759 (3)0.80383 (10)0.0391 (5)
H9B11.0090.16840.77420.077 (3)*
C100.8694 (4)0.2156 (4)0.91074 (12)0.0587 (8)
H10A0.92970.22620.94750.100 (5)*
H10B0.78040.12780.91310.100 (5)*
H10C0.81140.32040.90120.100 (5)*
C111.1446 (6)0.0480 (6)0.97981 (13)0.0809 (11)
H11A1.04760.12840.98040.100 (5)*
H11B1.09920.06120.99050.100 (5)*
H11C1.23610.08191.0070.100 (5)*
C121.3245 (6)0.2074 (5)0.90694 (18)0.0871 (12)
H12A1.41990.22130.93480.100 (5)*
H12B1.37440.20620.86840.100 (5)*
H12C1.24060.29930.91040.100 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0919 (18)0.0321 (10)0.0938 (17)0.0012 (11)0.0179 (15)0.0003 (9)
O20.0735 (13)0.0419 (11)0.0814 (14)0.0128 (10)0.0286 (13)0.0048 (9)
C10.0645 (17)0.0336 (13)0.0558 (15)0.0033 (13)0.0039 (14)0.0002 (10)
C30.0734 (19)0.0432 (15)0.0660 (18)0.0044 (14)0.0219 (17)0.0077 (12)
C3A0.0499 (14)0.0330 (12)0.0450 (13)0.0001 (11)0.0071 (12)0.0062 (9)
C40.0597 (17)0.0348 (12)0.0667 (17)0.0153 (12)0.0151 (15)0.0006 (12)
C50.0749 (19)0.0385 (14)0.0686 (18)0.0126 (14)0.0193 (17)0.0144 (12)
C5A0.0446 (12)0.0372 (12)0.0384 (11)0.0012 (11)0.0037 (10)0.0012 (9)
C60.0537 (15)0.0590 (16)0.0473 (14)0.0056 (14)0.0096 (13)0.0042 (12)
C70.0441 (15)0.091 (2)0.0595 (17)0.0051 (16)0.0102 (15)0.0033 (16)
C80.0543 (16)0.072 (2)0.084 (2)0.0206 (16)0.0167 (17)0.0073 (17)
C90.0545 (16)0.0464 (15)0.0709 (17)0.0171 (14)0.0049 (15)0.0000 (13)
C9A0.0395 (11)0.0348 (11)0.0405 (11)0.0083 (10)0.0023 (10)0.0025 (9)
C9B0.0453 (12)0.0311 (11)0.0410 (11)0.0017 (11)0.0025 (10)0.0006 (9)
C100.0536 (15)0.075 (2)0.0476 (15)0.0070 (15)0.0044 (13)0.0152 (14)
C110.084 (2)0.112 (3)0.0464 (16)0.013 (3)0.0105 (17)0.0190 (17)
C120.094 (3)0.079 (2)0.088 (3)0.029 (2)0.040 (2)0.0022 (19)
Geometric parameters (Å, º) top
O1—C11.199 (3)C7—H7A0.97
O2—C11.348 (4)C7—H7B0.97
O2—C31.449 (4)C8—C91.519 (5)
C1—C9B1.516 (3)C8—H8A0.97
C3—C3A1.498 (4)C8—H8B0.97
C3—H3A0.97C9—C9A1.538 (3)
C3—H3B0.97C9—H9A0.97
C3A—C41.315 (4)C9—H9B0.97
C3A—C9B1.496 (3)C9A—C101.523 (4)
C4—C51.498 (4)C9A—C9B1.540 (3)
C4—H40.91 (3)C9B—H9B10.98
C5—C5A1.532 (4)C10—H10A0.96
C5—H5A0.97C10—H10B0.96
C5—H5B0.97C10—H10C0.96
C5A—C9A1.560 (3)C11—H11A0.96
C5A—C61.561 (3)C11—H11B0.96
C5A—H5A10.98C11—H11C0.96
C6—C71.531 (4)C12—H12A0.96
C6—C111.534 (4)C12—H12B0.96
C6—C121.540 (5)C12—H12C0.96
C7—C81.511 (5)
C1—O2—C3111.4 (2)C7—C8—H8A109.6
O1—C1—O2120.4 (3)C9—C8—H8A109.6
O1—C1—C9B129.3 (3)C7—C8—H8B109.6
O2—C1—C9B110.3 (2)C9—C8—H8B109.6
O2—C3—C3A104.1 (2)H8A—C8—H8B108.1
O2—C3—H3A110.9C8—C9—C9A113.0 (2)
C3A—C3—H3A110.9C8—C9—H9A109
O2—C3—H3B110.9C9A—C9—H9A109
C3A—C3—H3B110.9C8—C9—H9B109
H3A—C3—H3B108.9C9A—C9—H9B109
C4—C3A—C9B123.9 (2)H9A—C9—H9B107.8
C4—C3A—C3128.9 (3)C10—C9A—C9110.8 (2)
C9B—C3A—C3106.8 (2)C10—C9A—C9B109.5 (2)
C3A—C4—C5121.6 (2)C9—C9A—C9B108.9 (2)
C3A—C4—H4123.5 (19)C10—C9A—C5A114.1 (2)
C5—C4—H4114.9 (19)C9—C9A—C5A108.8 (2)
C4—C5—C5A113.8 (2)C9B—C9A—C5A104.53 (18)
C4—C5—H5A108.8C3A—C9B—C1101.6 (2)
C5A—C5—H5A108.8C3A—C9B—C9A113.53 (19)
C4—C5—H5B108.8C1—C9B—C9A118.1 (2)
C5A—C5—H5B108.8C3A—C9B—H9B1107.7
H5A—C5—H5B107.7C1—C9B—H9B1107.7
C5—C5A—C9A112.2 (2)C9A—C9B—H9B1107.7
C5—C5A—C6113.0 (2)C9A—C10—H10A109.5
C9A—C5A—C6116.2 (2)C9A—C10—H10B109.5
C5—C5A—H5A1104.7H10A—C10—H10B109.5
C9A—C5A—H5A1104.7C9A—C10—H10C109.5
C6—C5A—H5A1104.7H10A—C10—H10C109.5
C7—C6—C11109.1 (3)H10B—C10—H10C109.5
C7—C6—C12107.5 (3)C6—C11—H11A109.5
C11—C6—C12107.9 (3)C6—C11—H11B109.5
C7—C6—C5A108.8 (2)H11A—C11—H11B109.5
C11—C6—C5A114.8 (3)C6—C11—H11C109.5
C12—C6—C5A108.6 (2)H11A—C11—H11C109.5
C8—C7—C6114.5 (2)H11B—C11—H11C109.5
C8—C7—H7A108.6C6—C12—H12A109.5
C6—C7—H7A108.6C6—C12—H12B109.5
C8—C7—H7B108.6H12A—C12—H12B109.5
C6—C7—H7B108.6C6—C12—H12C109.5
H7A—C7—H7B107.6H12A—C12—H12C109.5
C7—C8—C9110.4 (3)H12B—C12—H12C109.5
C3—O2—C1—O1179.8 (3)C8—C9—C9A—C9B167.1 (3)
C3—O2—C1—C9B1.3 (3)C8—C9—C9A—C5A53.7 (3)
C1—O2—C3—C3A13.5 (4)C5—C5A—C9A—C1057.9 (3)
O2—C3—C3A—C4150.1 (3)C6—C5A—C9A—C1074.3 (3)
O2—C3—C3A—C9B23.0 (3)C5—C5A—C9A—C9177.8 (2)
C9B—C3A—C4—C51.5 (5)C6—C5A—C9A—C950.0 (3)
C3—C3A—C4—C5173.5 (3)C5—C5A—C9A—C9B61.6 (3)
C3A—C4—C5—C5A8.2 (4)C6—C5A—C9A—C9B166.2 (2)
C4—C5—C5A—C9A41.4 (3)C4—C3A—C9B—C1150.4 (3)
C4—C5—C5A—C6175.2 (3)C3—C3A—C9B—C123.0 (3)
C5—C5A—C6—C7179.6 (3)C4—C3A—C9B—C9A22.6 (4)
C9A—C5A—C6—C748.5 (3)C3—C3A—C9B—C9A150.9 (2)
C5—C5A—C6—C1157.9 (4)O1—C1—C9B—C3A166.3 (3)
C9A—C5A—C6—C1174.0 (3)O2—C1—C9B—C3A15.4 (3)
C5—C5A—C6—C1263.0 (3)O1—C1—C9B—C9A41.4 (4)
C9A—C5A—C6—C12165.2 (3)O2—C1—C9B—C9A140.3 (2)
C11—C6—C7—C874.4 (3)C10—C9A—C9B—C3A71.3 (3)
C12—C6—C7—C8168.9 (3)C9—C9A—C9B—C3A167.5 (2)
C5A—C6—C7—C851.5 (3)C5A—C9A—C9B—C3A51.4 (3)
C6—C7—C8—C957.5 (4)C10—C9A—C9B—C147.6 (3)
C7—C8—C9—C9A58.3 (4)C9—C9A—C9B—C173.7 (3)
C8—C9—C9A—C1072.5 (3)C5A—C9A—C9B—C1170.2 (2)

Experimental details

Crystal data
Chemical formulaC15H22O2
Mr234.33
Crystal system, space groupOrthorhombic, P212121
Temperature (K)298
a, b, c (Å)7.4031 (2), 7.9250 (2), 22.9973 (8)
V3)1349.24 (7)
Z4
Radiation typeMo Kα
µ (mm1)0.07
Crystal size (mm)0.14 × 0.12 × 0.08
Data collection
DiffractometerNonius KappaCCD area-detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
4453, 1790, 1645
Rint0.066
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.061, 0.167, 1.18
No. of reflections1790
No. of parameters163
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.23, 0.19

Computer programs: COLLECT (Nonius, 1998), DENZO–SMN (Otwinowski & Minor, 1997), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003), WinGX (Farrugia, 1999).

 

Acknowledgements

We thank the Spanish Research Council (CSIC) for providing us with a free-of-charge licence for the Cambridge Structural Database. MZ recognizes support provided by the Center for Ecosystem Research in Patagonia (CIEP), under grant 205.023.040-1SP.

References

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