organic compounds
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
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 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); 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
Crystal data
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Data collection
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Refinement
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Data collection: APEX2 (Bruker, 2005); cell SAINT (Bruker, 2005); data reduction: SAINT; 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).
Supporting information
https://doi.org/10.1107/S1600536810033404/ci5157sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810033404/ci5157Isup2.hkl
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 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.
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
the could not be reliably determined and thus 1278 Friedel pairs were merged.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 (Watson & Zabel, 1982; Castaneda-Acosta et al., 1997).
In the
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).
Data collection: APEX2 (Bruker, 2005); cell
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).C15H20O5 | F(000) = 300 |
Mr = 280.31 | Dx = 1.284 Mg m−3 |
Monoclinic, P21 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2yb | Cell parameters from 8090 reflections |
a = 9.2295 (3) Å | θ = 2.5–26.5° |
b = 9.5431 (3) Å | µ = 0.10 mm−1 |
c = 9.3787 (3) Å | T = 298 K |
β = 118.662 (2)° | Prism, colourless |
V = 724.84 (4) Å3 | 0.27 × 0.18 × 0.12 mm |
Z = 2 |
Bruker X8 APEXII CCD area-detector diffractometer | 1378 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.031 |
Graphite monochromator | θmax = 26.7°, θmin = 2.5° |
φ and ω scans | h = −11→11 |
8090 measured reflections | k = −10→12 |
1617 independent reflections | l = −11→11 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.033 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.090 | H-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 parameters | Δρmax = 0.13 e Å−3 |
1 restraint | Δρmin = −0.13 e Å−3 |
C15H20O5 | V = 724.84 (4) Å3 |
Mr = 280.31 | Z = 2 |
Monoclinic, P21 | Mo Kα radiation |
a = 9.2295 (3) Å | µ = 0.10 mm−1 |
b = 9.5431 (3) Å | T = 298 K |
c = 9.3787 (3) Å | 0.27 × 0.18 × 0.12 mm |
β = 118.662 (2)° |
Bruker X8 APEXII CCD area-detector diffractometer | 1378 reflections with I > 2σ(I) |
8090 measured reflections | Rint = 0.031 |
1617 independent reflections |
R[F2 > 2σ(F2)] = 0.033 | 1 restraint |
wR(F2) = 0.090 | H-atom parameters constrained |
S = 1.05 | Δρmax = 0.13 e Å−3 |
1617 reflections | Δρmin = −0.13 e Å−3 |
184 parameters |
x | y | z | Uiso*/Ueq | ||
C1 | −0.1569 (3) | 0.2114 (3) | 0.0240 (3) | 0.0445 (5) | |
H1 | −0.0953 | 0.2863 | 0.0055 | 0.053* | |
C2 | −0.3412 (3) | 0.2235 (3) | −0.0757 (3) | 0.0567 (7) | |
H2A | −0.3919 | 0.1709 | −0.0227 | 0.068* | |
H2B | −0.3757 | 0.1811 | −0.1811 | 0.068* | |
C3 | −0.4043 (3) | 0.3738 (4) | −0.1004 (3) | 0.0638 (8) | |
H3A | −0.3743 | 0.4211 | −0.1741 | 0.077* | |
H3B | −0.5238 | 0.3729 | −0.1505 | 0.077* | |
C4 | −0.3354 (3) | 0.4546 (3) | 0.0564 (3) | 0.0522 (6) | |
C5 | −0.1856 (3) | 0.5389 (3) | 0.0973 (3) | 0.0493 (6) | |
H5 | −0.1470 | 0.5325 | 0.0167 | 0.059* | |
C6 | −0.0511 (2) | 0.5623 (2) | 0.2665 (3) | 0.0421 (5) | |
H6 | −0.0915 | 0.5477 | 0.3448 | 0.051* | |
C7 | 0.0972 (3) | 0.4660 (2) | 0.3050 (3) | 0.0367 (5) | |
H7 | 0.0907 | 0.4403 | 0.2009 | 0.044* | |
C8 | 0.1049 (3) | 0.3287 (2) | 0.3942 (3) | 0.0423 (5) | |
H8A | 0.2046 | 0.3294 | 0.4986 | 0.051* | |
H8B | 0.0116 | 0.3261 | 0.4149 | 0.051* | |
C9 | 0.1036 (3) | 0.1953 (2) | 0.3041 (3) | 0.0395 (5) | |
H9 | 0.1641 | 0.2126 | 0.2439 | 0.047* | |
C10 | −0.0689 (3) | 0.1455 (2) | 0.1862 (3) | 0.0407 (5) | |
C11 | 0.2419 (3) | 0.5625 (2) | 0.3892 (3) | 0.0399 (5) | |
C12 | 0.1773 (3) | 0.7075 (2) | 0.3533 (3) | 0.0465 (5) | |
C13 | 0.3997 (3) | 0.5360 (3) | 0.4776 (3) | 0.0601 (7) | |
H13A | 0.4749 | 0.6094 | 0.5198 | 0.072* | |
H13B | 0.4367 | 0.4438 | 0.4980 | 0.072* | |
C14 | −0.1584 (3) | 0.0708 (3) | 0.2633 (3) | 0.0589 (7) | |
H14A | −0.1411 | 0.1202 | 0.3593 | 0.088* | |
H14B | −0.1164 | −0.0229 | 0.2917 | 0.088* | |
H14C | −0.2744 | 0.0675 | 0.1877 | 0.088* | |
C15 | −0.3799 (3) | 0.4050 (3) | 0.1816 (3) | 0.0599 (7) | |
H15A | −0.3367 | 0.4691 | 0.2715 | 0.090* | |
H15B | −0.3336 | 0.3137 | 0.2190 | 0.090* | |
H15C | −0.4979 | 0.4004 | 0.1347 | 0.090* | |
O1 | −0.3421 (2) | 0.6072 (2) | 0.0388 (3) | 0.0650 (5) | |
O2 | 0.1910 (2) | 0.09367 (17) | 0.4267 (2) | 0.0569 (5) | |
H2 | 0.1973 | 0.0204 | 0.3843 | 0.085* | |
O3 | 0.0115 (2) | 0.70565 (16) | 0.2779 (2) | 0.0539 (4) | |
O4 | 0.2528 (2) | 0.81591 (19) | 0.3811 (2) | 0.0653 (5) | |
O5 | −0.0845 (2) | 0.07350 (19) | 0.0434 (2) | 0.0549 (4) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0426 (11) | 0.0524 (14) | 0.0442 (11) | −0.0061 (10) | 0.0254 (9) | −0.0082 (11) |
C2 | 0.0443 (13) | 0.077 (2) | 0.0458 (13) | −0.0123 (12) | 0.0194 (10) | −0.0122 (13) |
C3 | 0.0351 (12) | 0.091 (2) | 0.0544 (15) | 0.0047 (12) | 0.0123 (11) | 0.0073 (14) |
C4 | 0.0341 (11) | 0.0619 (16) | 0.0599 (15) | 0.0111 (10) | 0.0221 (10) | 0.0078 (12) |
C5 | 0.0391 (11) | 0.0543 (14) | 0.0561 (13) | 0.0127 (10) | 0.0241 (10) | 0.0159 (11) |
C6 | 0.0454 (11) | 0.0330 (12) | 0.0557 (13) | 0.0072 (9) | 0.0306 (10) | 0.0073 (10) |
C7 | 0.0431 (12) | 0.0284 (10) | 0.0398 (11) | 0.0044 (8) | 0.0210 (9) | 0.0030 (8) |
C8 | 0.0550 (12) | 0.0300 (11) | 0.0416 (11) | 0.0007 (10) | 0.0228 (9) | 0.0020 (9) |
C9 | 0.0446 (11) | 0.0293 (10) | 0.0465 (12) | 0.0023 (9) | 0.0232 (10) | 0.0002 (9) |
C10 | 0.0484 (12) | 0.0347 (11) | 0.0488 (12) | −0.0043 (9) | 0.0311 (10) | −0.0063 (9) |
C11 | 0.0450 (11) | 0.0321 (11) | 0.0442 (11) | 0.0009 (9) | 0.0227 (9) | 0.0015 (9) |
C12 | 0.0569 (13) | 0.0331 (12) | 0.0544 (13) | 0.0020 (11) | 0.0306 (11) | −0.0006 (11) |
C13 | 0.0461 (13) | 0.0519 (15) | 0.0699 (16) | 0.0010 (11) | 0.0178 (11) | 0.0071 (13) |
C14 | 0.0654 (15) | 0.0529 (16) | 0.0695 (16) | −0.0123 (13) | 0.0413 (13) | 0.0045 (13) |
C15 | 0.0536 (14) | 0.0636 (17) | 0.0754 (18) | 0.0038 (13) | 0.0413 (13) | 0.0003 (13) |
O1 | 0.0441 (10) | 0.0637 (13) | 0.0835 (12) | 0.0202 (8) | 0.0276 (9) | 0.0214 (10) |
O2 | 0.0673 (11) | 0.0297 (8) | 0.0630 (10) | 0.0118 (8) | 0.0226 (9) | 0.0057 (8) |
O3 | 0.0574 (10) | 0.0299 (8) | 0.0780 (11) | 0.0121 (8) | 0.0355 (9) | 0.0071 (9) |
O4 | 0.0786 (13) | 0.0307 (8) | 0.0896 (13) | −0.0083 (8) | 0.0429 (10) | −0.0048 (9) |
O5 | 0.0596 (9) | 0.0517 (10) | 0.0604 (10) | −0.0073 (8) | 0.0342 (8) | −0.0212 (8) |
C1—O5 | 1.447 (3) | C8—C9 | 1.525 (3) |
C1—C10 | 1.477 (3) | C8—H8A | 0.97 |
C1—C2 | 1.502 (3) | C8—H8B | 0.97 |
C1—H1 | 0.98 | C9—O2 | 1.422 (3) |
C2—C3 | 1.524 (4) | C9—C10 | 1.515 (3) |
C2—H2A | 0.97 | C9—H9 | 0.98 |
C2—H2B | 0.97 | C10—O5 | 1.449 (3) |
C3—C4 | 1.505 (4) | C10—C14 | 1.512 (3) |
C3—H3A | 0.97 | C11—C13 | 1.310 (3) |
C3—H3B | 0.97 | C11—C12 | 1.480 (3) |
C4—O1 | 1.463 (3) | C12—O4 | 1.204 (3) |
C4—C5 | 1.482 (4) | C12—O3 | 1.343 (3) |
C4—C15 | 1.495 (4) | C13—H13A | 0.93 |
C5—O1 | 1.432 (3) | C13—H13B | 0.93 |
C5—C6 | 1.490 (3) | C14—H14A | 0.96 |
C5—H5 | 0.98 | C14—H14B | 0.96 |
C6—O3 | 1.469 (3) | C14—H14C | 0.96 |
C6—C7 | 1.541 (3) | C15—H15A | 0.96 |
C6—H6 | 0.98 | C15—H15B | 0.96 |
C7—C11 | 1.498 (3) | C15—H15C | 0.96 |
C7—C8 | 1.537 (3) | O2—H2 | 0.82 |
C7—H7 | 0.98 | ||
O5—C1—C10 | 59.41 (15) | C9—C8—H8A | 108.5 |
O5—C1—C2 | 117.7 (2) | C7—C8—H8A | 108.5 |
C10—C1—C2 | 124.9 (2) | C9—C8—H8B | 108.5 |
O5—C1—H1 | 114.4 | C7—C8—H8B | 108.5 |
C10—C1—H1 | 114.4 | H8A—C8—H8B | 107.5 |
C2—C1—H1 | 114.4 | O2—C9—C10 | 111.51 (18) |
C1—C2—C3 | 113.8 (2) | O2—C9—C8 | 105.69 (16) |
C1—C2—H2A | 108.8 | C10—C9—C8 | 113.10 (17) |
C3—C2—H2A | 108.8 | O2—C9—H9 | 108.8 |
C1—C2—H2B | 108.8 | C10—C9—H9 | 108.8 |
C3—C2—H2B | 108.8 | C8—C9—H9 | 108.8 |
H2A—C2—H2B | 107.7 | O5—C10—C1 | 59.26 (15) |
C4—C3—C2 | 112.5 (2) | O5—C10—C14 | 112.5 (2) |
C4—C3—H3A | 109.1 | C1—C10—C14 | 122.4 (2) |
C2—C3—H3A | 109.1 | O5—C10—C9 | 115.25 (17) |
C4—C3—H3B | 109.1 | C1—C10—C9 | 119.00 (18) |
C2—C3—H3B | 109.1 | C14—C10—C9 | 115.0 (2) |
H3A—C3—H3B | 107.8 | C13—C11—C12 | 121.9 (2) |
O1—C4—C5 | 58.19 (16) | C13—C11—C7 | 130.9 (2) |
O1—C4—C15 | 113.1 (2) | C12—C11—C7 | 107.19 (18) |
C5—C4—C15 | 122.8 (2) | O4—C12—O3 | 121.4 (2) |
O1—C4—C3 | 115.1 (2) | O4—C12—C11 | 128.7 (2) |
C5—C4—C3 | 115.8 (2) | O3—C12—C11 | 109.87 (19) |
C15—C4—C3 | 117.3 (2) | C11—C13—H13A | 120.0 |
O1—C5—C4 | 60.23 (15) | C11—C13—H13B | 120.0 |
O1—C5—C6 | 120.8 (2) | H13A—C13—H13B | 120.0 |
C4—C5—C6 | 123.7 (2) | C10—C14—H14A | 109.5 |
O1—C5—H5 | 113.9 | C10—C14—H14B | 109.5 |
C4—C5—H5 | 113.9 | H14A—C14—H14B | 109.5 |
C6—C5—H5 | 113.9 | C10—C14—H14C | 109.5 |
O3—C6—C5 | 108.32 (18) | H14A—C14—H14C | 109.5 |
O3—C6—C7 | 105.30 (16) | H14B—C14—H14C | 109.5 |
C5—C6—C7 | 110.70 (18) | C4—C15—H15A | 109.5 |
O3—C6—H6 | 110.8 | C4—C15—H15B | 109.5 |
C5—C6—H6 | 110.8 | H15A—C15—H15B | 109.5 |
C7—C6—H6 | 110.8 | C4—C15—H15C | 109.5 |
C11—C7—C8 | 116.15 (18) | H15A—C15—H15C | 109.5 |
C11—C7—C6 | 102.94 (17) | H15B—C15—H15C | 109.5 |
C8—C7—C6 | 116.07 (17) | C5—O1—C4 | 61.57 (16) |
C11—C7—H7 | 107.0 | C9—O2—H2 | 109.5 |
C8—C7—H7 | 107.0 | C12—O3—C6 | 111.09 (16) |
C6—C7—H7 | 107.0 | C1—O5—C10 | 61.33 (14) |
C9—C8—C7 | 115.12 (17) |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···O4i | 0.82 | 2.02 | 2.787 (3) | 155 |
Symmetry code: (i) x, y−1, z. |
Experimental details
Crystal data | |
Chemical formula | C15H20O5 |
Mr | 280.31 |
Crystal system, space group | Monoclinic, P21 |
Temperature (K) | 298 |
a, b, c (Å) | 9.2295 (3), 9.5431 (3), 9.3787 (3) |
β (°) | 118.662 (2) |
V (Å3) | 724.84 (4) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.27 × 0.18 × 0.12 |
Data collection | |
Diffractometer | Bruker X8 APEXII CCD area-detector |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8090, 1617, 1378 |
Rint | 0.031 |
(sin θ/λ)max (Å−1) | 0.632 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.033, 0.090, 1.05 |
No. of reflections | 1617 |
No. of parameters | 184 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 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).
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···O4i | 0.82 | 2.02 | 2.787 (3) | 155 |
Symmetry code: (i) x, y−1, 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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This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
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.