organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

9β-Hy­dr­oxy-1β,10α-ep­­oxy­parthenolide

aLaboratoire de Chimie Bioorganique et Analytique, URAC 22, BP 146, FSTM, Université Hassan II, Mohammedia-Casablanca 20810 Mohammedia, Morocco, bLaboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Avenue Ibn Battouta, BP 1014 Rabat, Morocco, and cLaboratoire de Chimie des Substances Naturelles, URAC16. Faculté des Sciences Semlalia, BP 2390 Bd My Abdellah, 40000 Marrakech, Morocco
*Correspondence e-mail: abenharref@yahoo.fr

(Received 14 August 2010; accepted 18 August 2010; online 25 August 2010)

The title compound, C15H20O5 (systematic name: 5-hydroxy-1a,4a-dimethyl-7-methyleneperhydrodioxireno[5,6:9,10]cyclo­deca[1,2-b]furan-8-one), was obtained by the reaction of 3-chloro­perbenzoic acid with 9β-hy­droxy­parthenolide. The five-membered ring adopts a twist conformation, whereas the ten-membered ring displays an approximate chair–chair conformation. In the crystal structure, mol­ecules are linked into chains propagating along the b axis by inter­molecular O—H⋯O hydrogen bonds.

Related literature

For background to the medicinal uses of the plant Anvillea radiata, see: Abdel Sattar et al. (1996[Abdel Sattar, E., Galal, A. M. & Mossa, J. S. (1996). J. Nat. Prod. 59, 403-405.]); Bellakhdar (1997[Bellakhdar, J. (1997). La Pharmacopée Marocaine Traditionnelle, pp. 272-274. Paris: Edition Ibis Press.]); El Hassany et al. (2004[El Hassany, B., El Hanbali, F., Akssira, M., Mellouki, F., Haidou, A. & Barero, A. F. (2004). Fitoterapia, 75, 573-576.]); Qureshi et al. (1990[Qureshi, S., Ageel, A. M., Al-Yahya, M. A., Tariq, M., Mossa, J. S. & Shah, A. H. (1990). J. Ethnopharmacol. 28, 157-162]). For ring puckering parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]). For conformations of ten-membered rings, see: Castaneda-Acosta et al. (1997[Castaneda-Acosta, J., Pentes, H. G., Fronczek, F. R. & Fischer, N. H. (1997). J. Chem. Crystallogr. 27, 635-639.]); Watson & Zabel (1982[Watson, W. H. & Zabel, V. (1982). Acta Cryst. B38, 834-838.]).

[Scheme 1]

Experimental

Crystal data
  • C15H20O5

  • Mr = 280.31

  • Monoclinic, P 21

  • a = 9.2295 (3) Å

  • b = 9.5431 (3) Å

  • c = 9.3787 (3) Å

  • β = 118.662 (2)°

  • V = 724.84 (4) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 298 K

  • 0.27 × 0.18 × 0.12 mm

Data collection
  • Bruker X8 APEXII CCD area-detector diffractometer

  • 8090 measured reflections

  • 1617 independent reflections

  • 1378 reflections with I > 2σ(I)

  • Rint = 0.031

Refinement
  • R[F2 > 2σ(F2)] = 0.033

  • wR(F2) = 0.090

  • S = 1.05

  • 1617 reflections

  • 184 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.13 e Å−3

  • Δρmin = −0.13 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2⋯O4i 0.82 2.02 2.787 (3) 155
Symmetry code: (i) x, y-1, z.

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2005[Bruker (2005). APEX2 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: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

Anvillea radiata Coss. & Dur. (Asteraceae) is a wild plant predominantly distributed in steppes of North Africa (Morocco and Algeria). The plant is used in the folk medicine for the treatment of dysentery, gastric-intestinal disorders (Bellakhdar, 1997), hypoglycemic activity (Qureshi et al., 1990), and has been reported to have antitumoral activity (Abdel Sattar et al., 1996). In our study of different Moroccan endemic plants, we have demonstrated that the aerial parts of Anvillea radiata Coss and Dur could be used as a renewable source of 9-hydroxyparthenolide (El Hassany, et al., 2004). This work focuses on the preparation of 1β-10α-epoxy-9β-hydroxyparthenolide from the epoxydation of 9β-hydroxy parthenolide.

The molecular structure of the title compound is shown in Fig. 1. The five-membered ring adopts a twist conformation, as indicated by Cremer & Pople (1975) puckering parameters Q = 0.186 (3) Å and φ = 61.5 (8)°. The ten-membered ring displays an approximate chair-chair conformation. This is the typical conformation found in other sesquiterpenes lactones (Watson & Zabel, 1982; Castaneda-Acosta et al., 1997).

In the crystal structure, molecules are linked into chains (Fig. 2) running along the b axis by intermolecular O—H···O hydrogen bonds (Table 1) involving the O2 and O4 atoms.

Related literature top

For background to the medicinal uses of the plant Anvillea radiata, see: Abdel Sattar et al. (1996); Bellakhdar (1997); El Hassany et al. (2004); Qureshi et al. (1990). For ring puckering parameters, see: Cremer & Pople (1975). For conformations of ten-membered rings, see: Castaneda-Acosta et al. (1997); Watson & Zabel (1982).

Experimental top

The title compound was obtained by treatment of 9β-Hydroxyparthenolide (500 mg) by m-chloroperbenzoic acid (250 mg) in CH2Cl2 (75 ml). The mixture was stirred for 30 min at room temperature and treated with aqueous solution of Na2CO3 (10%), then extracted by CH2Cl2. The residue obtained after evaporation of CH2Cl2, was chromatographed on a silica gel column with hexane-ethylacetate (50/50) as an eluent, to isolate 350 mg of the title compound in 75% yield. It was recrystallized from CH2Cl2 (m.p. 363–365 K). The structure of the compound was analyzed by 1H and 13C-NMR and confirmed by X-ray analysis.

Refinement top

All H atoms were positioned geometrically [C–H = 0.96 Å (methyl), 0.97 Å (methylene) and 0.98Å (methine)]and treated as riding with Uiso(H) = 1.2Ueq(methylene/methine C and O) or Uiso(H) = 1.5Ueq(methyl C). In the absence of significant anomalous scattering, the absolute configuration could not be reliably determined and thus 1278 Friedel pairs were merged.

Structure description top

Anvillea radiata Coss. & Dur. (Asteraceae) is a wild plant predominantly distributed in steppes of North Africa (Morocco and Algeria). The plant is used in the folk medicine for the treatment of dysentery, gastric-intestinal disorders (Bellakhdar, 1997), hypoglycemic activity (Qureshi et al., 1990), and has been reported to have antitumoral activity (Abdel Sattar et al., 1996). In our study of different Moroccan endemic plants, we have demonstrated that the aerial parts of Anvillea radiata Coss and Dur could be used as a renewable source of 9-hydroxyparthenolide (El Hassany, et al., 2004). This work focuses on the preparation of 1β-10α-epoxy-9β-hydroxyparthenolide from the epoxydation of 9β-hydroxy parthenolide.

The molecular structure of the title compound is shown in Fig. 1. The five-membered ring adopts a twist conformation, as indicated by Cremer & Pople (1975) puckering parameters Q = 0.186 (3) Å and φ = 61.5 (8)°. The ten-membered ring displays an approximate chair-chair conformation. This is the typical conformation found in other sesquiterpenes lactones (Watson & Zabel, 1982; Castaneda-Acosta et al., 1997).

In the crystal structure, molecules are linked into chains (Fig. 2) running along the b axis by intermolecular O—H···O hydrogen bonds (Table 1) involving the O2 and O4 atoms.

For background to the medicinal uses of the plant Anvillea radiata, see: Abdel Sattar et al. (1996); Bellakhdar (1997); El Hassany et al. (2004); Qureshi et al. (1990). For ring puckering parameters, see: Cremer & Pople (1975). For conformations of ten-membered rings, see: Castaneda-Acosta et al. (1997); Watson & Zabel (1982).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); 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) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound, with the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are represented as small spheres of arbitrary radii.
[Figure 2] Fig. 2. Partial packing view, showing C—H···O hydrogen-bonded chains parallel to the b axis. H atoms not involved in hydrogen bonding (dashed lines) have been omitted for clarity.
5-hydroxy-1a,4a-dimethyl-7- methyleneperhydrodioxireno[5,6:9,10]cyclodeca[1,2-b]furan-8-one top
Crystal data top
C15H20O5F(000) = 300
Mr = 280.31Dx = 1.284 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 8090 reflections
a = 9.2295 (3) Åθ = 2.5–26.5°
b = 9.5431 (3) ŵ = 0.10 mm1
c = 9.3787 (3) ÅT = 298 K
β = 118.662 (2)°Prism, colourless
V = 724.84 (4) Å30.27 × 0.18 × 0.12 mm
Z = 2
Data collection top
Bruker X8 APEXII CCD area-detector
diffractometer
1378 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.031
Graphite monochromatorθmax = 26.7°, θmin = 2.5°
φ and ω scansh = 1111
8090 measured reflectionsk = 1012
1617 independent reflectionsl = 1111
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.033Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.090H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0541P)2 + 0.0327P]
where P = (Fo2 + 2Fc2)/3
1617 reflections(Δ/σ)max = 0.001
184 parametersΔρmax = 0.13 e Å3
1 restraintΔρmin = 0.13 e Å3
Crystal data top
C15H20O5V = 724.84 (4) Å3
Mr = 280.31Z = 2
Monoclinic, P21Mo Kα radiation
a = 9.2295 (3) ŵ = 0.10 mm1
b = 9.5431 (3) ÅT = 298 K
c = 9.3787 (3) Å0.27 × 0.18 × 0.12 mm
β = 118.662 (2)°
Data collection top
Bruker X8 APEXII CCD area-detector
diffractometer
1378 reflections with I > 2σ(I)
8090 measured reflectionsRint = 0.031
1617 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0331 restraint
wR(F2) = 0.090H-atom parameters constrained
S = 1.05Δρmax = 0.13 e Å3
1617 reflectionsΔρmin = 0.13 e Å3
184 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.1569 (3)0.2114 (3)0.0240 (3)0.0445 (5)
H10.09530.28630.00550.053*
C20.3412 (3)0.2235 (3)0.0757 (3)0.0567 (7)
H2A0.39190.17090.02270.068*
H2B0.37570.18110.18110.068*
C30.4043 (3)0.3738 (4)0.1004 (3)0.0638 (8)
H3A0.37430.42110.17410.077*
H3B0.52380.37290.15050.077*
C40.3354 (3)0.4546 (3)0.0564 (3)0.0522 (6)
C50.1856 (3)0.5389 (3)0.0973 (3)0.0493 (6)
H50.14700.53250.01670.059*
C60.0511 (2)0.5623 (2)0.2665 (3)0.0421 (5)
H60.09150.54770.34480.051*
C70.0972 (3)0.4660 (2)0.3050 (3)0.0367 (5)
H70.09070.44030.20090.044*
C80.1049 (3)0.3287 (2)0.3942 (3)0.0423 (5)
H8A0.20460.32940.49860.051*
H8B0.01160.32610.41490.051*
C90.1036 (3)0.1953 (2)0.3041 (3)0.0395 (5)
H90.16410.21260.24390.047*
C100.0689 (3)0.1455 (2)0.1862 (3)0.0407 (5)
C110.2419 (3)0.5625 (2)0.3892 (3)0.0399 (5)
C120.1773 (3)0.7075 (2)0.3533 (3)0.0465 (5)
C130.3997 (3)0.5360 (3)0.4776 (3)0.0601 (7)
H13A0.47490.60940.51980.072*
H13B0.43670.44380.49800.072*
C140.1584 (3)0.0708 (3)0.2633 (3)0.0589 (7)
H14A0.14110.12020.35930.088*
H14B0.11640.02290.29170.088*
H14C0.27440.06750.18770.088*
C150.3799 (3)0.4050 (3)0.1816 (3)0.0599 (7)
H15A0.33670.46910.27150.090*
H15B0.33360.31370.21900.090*
H15C0.49790.40040.13470.090*
O10.3421 (2)0.6072 (2)0.0388 (3)0.0650 (5)
O20.1910 (2)0.09367 (17)0.4267 (2)0.0569 (5)
H20.19730.02040.38430.085*
O30.0115 (2)0.70565 (16)0.2779 (2)0.0539 (4)
O40.2528 (2)0.81591 (19)0.3811 (2)0.0653 (5)
O50.0845 (2)0.07350 (19)0.0434 (2)0.0549 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0426 (11)0.0524 (14)0.0442 (11)0.0061 (10)0.0254 (9)0.0082 (11)
C20.0443 (13)0.077 (2)0.0458 (13)0.0123 (12)0.0194 (10)0.0122 (13)
C30.0351 (12)0.091 (2)0.0544 (15)0.0047 (12)0.0123 (11)0.0073 (14)
C40.0341 (11)0.0619 (16)0.0599 (15)0.0111 (10)0.0221 (10)0.0078 (12)
C50.0391 (11)0.0543 (14)0.0561 (13)0.0127 (10)0.0241 (10)0.0159 (11)
C60.0454 (11)0.0330 (12)0.0557 (13)0.0072 (9)0.0306 (10)0.0073 (10)
C70.0431 (12)0.0284 (10)0.0398 (11)0.0044 (8)0.0210 (9)0.0030 (8)
C80.0550 (12)0.0300 (11)0.0416 (11)0.0007 (10)0.0228 (9)0.0020 (9)
C90.0446 (11)0.0293 (10)0.0465 (12)0.0023 (9)0.0232 (10)0.0002 (9)
C100.0484 (12)0.0347 (11)0.0488 (12)0.0043 (9)0.0311 (10)0.0063 (9)
C110.0450 (11)0.0321 (11)0.0442 (11)0.0009 (9)0.0227 (9)0.0015 (9)
C120.0569 (13)0.0331 (12)0.0544 (13)0.0020 (11)0.0306 (11)0.0006 (11)
C130.0461 (13)0.0519 (15)0.0699 (16)0.0010 (11)0.0178 (11)0.0071 (13)
C140.0654 (15)0.0529 (16)0.0695 (16)0.0123 (13)0.0413 (13)0.0045 (13)
C150.0536 (14)0.0636 (17)0.0754 (18)0.0038 (13)0.0413 (13)0.0003 (13)
O10.0441 (10)0.0637 (13)0.0835 (12)0.0202 (8)0.0276 (9)0.0214 (10)
O20.0673 (11)0.0297 (8)0.0630 (10)0.0118 (8)0.0226 (9)0.0057 (8)
O30.0574 (10)0.0299 (8)0.0780 (11)0.0121 (8)0.0355 (9)0.0071 (9)
O40.0786 (13)0.0307 (8)0.0896 (13)0.0083 (8)0.0429 (10)0.0048 (9)
O50.0596 (9)0.0517 (10)0.0604 (10)0.0073 (8)0.0342 (8)0.0212 (8)
Geometric parameters (Å, º) top
C1—O51.447 (3)C8—C91.525 (3)
C1—C101.477 (3)C8—H8A0.97
C1—C21.502 (3)C8—H8B0.97
C1—H10.98C9—O21.422 (3)
C2—C31.524 (4)C9—C101.515 (3)
C2—H2A0.97C9—H90.98
C2—H2B0.97C10—O51.449 (3)
C3—C41.505 (4)C10—C141.512 (3)
C3—H3A0.97C11—C131.310 (3)
C3—H3B0.97C11—C121.480 (3)
C4—O11.463 (3)C12—O41.204 (3)
C4—C51.482 (4)C12—O31.343 (3)
C4—C151.495 (4)C13—H13A0.93
C5—O11.432 (3)C13—H13B0.93
C5—C61.490 (3)C14—H14A0.96
C5—H50.98C14—H14B0.96
C6—O31.469 (3)C14—H14C0.96
C6—C71.541 (3)C15—H15A0.96
C6—H60.98C15—H15B0.96
C7—C111.498 (3)C15—H15C0.96
C7—C81.537 (3)O2—H20.82
C7—H70.98
O5—C1—C1059.41 (15)C9—C8—H8A108.5
O5—C1—C2117.7 (2)C7—C8—H8A108.5
C10—C1—C2124.9 (2)C9—C8—H8B108.5
O5—C1—H1114.4C7—C8—H8B108.5
C10—C1—H1114.4H8A—C8—H8B107.5
C2—C1—H1114.4O2—C9—C10111.51 (18)
C1—C2—C3113.8 (2)O2—C9—C8105.69 (16)
C1—C2—H2A108.8C10—C9—C8113.10 (17)
C3—C2—H2A108.8O2—C9—H9108.8
C1—C2—H2B108.8C10—C9—H9108.8
C3—C2—H2B108.8C8—C9—H9108.8
H2A—C2—H2B107.7O5—C10—C159.26 (15)
C4—C3—C2112.5 (2)O5—C10—C14112.5 (2)
C4—C3—H3A109.1C1—C10—C14122.4 (2)
C2—C3—H3A109.1O5—C10—C9115.25 (17)
C4—C3—H3B109.1C1—C10—C9119.00 (18)
C2—C3—H3B109.1C14—C10—C9115.0 (2)
H3A—C3—H3B107.8C13—C11—C12121.9 (2)
O1—C4—C558.19 (16)C13—C11—C7130.9 (2)
O1—C4—C15113.1 (2)C12—C11—C7107.19 (18)
C5—C4—C15122.8 (2)O4—C12—O3121.4 (2)
O1—C4—C3115.1 (2)O4—C12—C11128.7 (2)
C5—C4—C3115.8 (2)O3—C12—C11109.87 (19)
C15—C4—C3117.3 (2)C11—C13—H13A120.0
O1—C5—C460.23 (15)C11—C13—H13B120.0
O1—C5—C6120.8 (2)H13A—C13—H13B120.0
C4—C5—C6123.7 (2)C10—C14—H14A109.5
O1—C5—H5113.9C10—C14—H14B109.5
C4—C5—H5113.9H14A—C14—H14B109.5
C6—C5—H5113.9C10—C14—H14C109.5
O3—C6—C5108.32 (18)H14A—C14—H14C109.5
O3—C6—C7105.30 (16)H14B—C14—H14C109.5
C5—C6—C7110.70 (18)C4—C15—H15A109.5
O3—C6—H6110.8C4—C15—H15B109.5
C5—C6—H6110.8H15A—C15—H15B109.5
C7—C6—H6110.8C4—C15—H15C109.5
C11—C7—C8116.15 (18)H15A—C15—H15C109.5
C11—C7—C6102.94 (17)H15B—C15—H15C109.5
C8—C7—C6116.07 (17)C5—O1—C461.57 (16)
C11—C7—H7107.0C9—O2—H2109.5
C8—C7—H7107.0C12—O3—C6111.09 (16)
C6—C7—H7107.0C1—O5—C1061.33 (14)
C9—C8—C7115.12 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O4i0.822.022.787 (3)155
Symmetry code: (i) x, y1, z.

Experimental details

Crystal data
Chemical formulaC15H20O5
Mr280.31
Crystal system, space groupMonoclinic, P21
Temperature (K)298
a, b, c (Å)9.2295 (3), 9.5431 (3), 9.3787 (3)
β (°) 118.662 (2)
V3)724.84 (4)
Z2
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.27 × 0.18 × 0.12
Data collection
DiffractometerBruker X8 APEXII CCD area-detector
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
8090, 1617, 1378
Rint0.031
(sin θ/λ)max1)0.632
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.033, 0.090, 1.05
No. of reflections1617
No. of parameters184
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.13, 0.13

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia,1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O4i0.822.022.787 (3)155
Symmetry code: (i) x, y1, z.
 

Acknowledgements

The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray diffraction measurements.

References

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