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

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ISSN: 2056-9890

5α-Hy­dr­oxy­eudesm-4(15),11(13)-dien-8β,12-olide

aResearch Center of Medical Chemistry and Chemical Biology, Chongqing Technology and Business University, Chongqing 400067, People's Republic of China
*Correspondence e-mail: gaoxue@ctbu.edu.cn

(Received 8 March 2012; accepted 22 March 2012; online 28 March 2012)

The title compound, C15H20O3, a sesquiterpene lactone, was isolated from the aerial parts of Carpesium minus Hemsl. (Compositae). The mol­ecule is composed of three rings, with the two cyclo­hexane rings in chair conformations and the cyclo­pentane ring adopting a twist conformation. The A/B ring junction is trans-fused. The absolute configuration shown has been arbitrarily assigned. In the crystal, mol­ecules are linked into [100] chains by O—H⋯O hydrogen bonds.

Related literature

For the isolation and biological activity of the title compound, see: Lee et al. (2002[Lee, J. S., Min, B. S., Lee, S. M., Na, M. K., Kwon, B. M., Lee, C. O., Kim, Y. H. & Bae, K. H. (2002). Planta Med. 68, 745-747.]); Yang et al. (2002[Yang, C., Shi, Y. P. & Jia, Z. J. (2002). Planta Med. 68, 626-630.]); Li et al. (2011[Li, X. W., Weng, L., Gao, X., Zhao, Y., Pang, F., Liu, J. H., Zhang, H. F. & Hu, J. F. (2011). Bioorg. Med. Chem. Lett. 21, 366-372.]). For conformational analysis, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C15H20O3

  • Mr = 248.31

  • Monoclinic, P 21

  • a = 7.893 (2) Å

  • b = 7.034 (2) Å

  • c = 12.166 (4) Å

  • β = 101.154 (3)°

  • V = 662.7 (3) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 296 K

  • 0.23 × 0.20 × 0.19 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2006[Bruker (2006). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.981, Tmax = 0.984

  • 3673 measured reflections

  • 1323 independent reflections

  • 1159 reflections with I > 2σ(I)

  • Rint = 0.024

Refinement
  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.084

  • S = 1.08

  • 1323 reflections

  • 165 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.12 e Å−3

  • Δρmin = −0.17 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1A⋯O3i 0.82 2.06 2.868 (2) 168
Symmetry code: (i) x+1, y, z.

Data collection: APEX2 (Bruker, 2006[Bruker (2006). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2006[Bruker (2006). APEX2, SAINT and SADABS. 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.

Supporting information


Comment top

The title compound, 5α-hydroxyeudesm-4(15),11 (13)-dien-8β,12-olide (Fig.1), was isolated from the medicinal plant Carpesium minus (Compositae). This plant has been used to reduce swelling, relieve pain and as a detoxifying agent. The compound was identified by NMR spectra, which were compared with the previous reports (Lee et al., 2002; Yang et al., 2002; Li et al., 2011). Herewith, we present its crystal structure.

The molecule of the title compound has three fused rings consisting of two six- and one five-membered rings (A/B/C). The A/B ring junction is trans-fused and B/C is cis-fused. The two cyclohexane rings have chair conformations with puckering parameters (Cremer & Pople,1975) Q = 0.571 (2) Å, θ = 175.7 (2)° and φ = 134 (4)° for the A ring and Q = 0.512 (2) Å, θ = 156.4 (2)° and φ = 344.9 (6)° for the B ring; the cyclopentane ring adopts a twist conformation with puckering parameters Q = 0.258 (2) Å and φ = 237.1 (4)°. In the crystal, the molecules are linked into chains by intermolecular O—H···O hydrogen bonds.

Related literature top

For the isolation and biological activity of the title compound, see: Lee et al. (2002); Yang et al. (2002); Li et al. (2011). For conformational analysis, see: Cremer & Pople (1975).

Experimental top

The air-dried whole plants of Carpesium minus (3.1 g) were pulverized and extracted with 95% EtOH and yielded 439 g of crude extract, which was then suspended in 2 L water. The suspension was partitioned with EtOAc (3×800 ml) to give a EtOAc-soluble portion, and a water-soluble fraction. After removal of the EtOAc under reduced pressure, 356 g of dark residue was obtained, and this was subjected to silica-gel chromatography, eluted with a stepwise gradient solvent system of petroleum/acetone 50: 1 to 0: 1 (v/v), to yield six major fractions (monitored by TLC). The third fraction (68 g) was rechromatographed on silica gel using a chloroform/MeOH (1: 0 to 30: 1) system and three fractions (Fr.A—Fr.C) were collected. Fr.B was further fractionated on a silica gel column using petroleum/EtOAc (3: 1) to give pure the title compound as colorless crystals.

Refinement top

All H atoms were placed in geometrically calculated positions, and allowed to ride on their parent atoms with O—H = 0.82 Å and C—H = 0.93–0.98 Å, and with Uiso(H) = xUeq (C), where x = 1.5 for methyl H atoms and hydroxyl group H atoms, and x = 1.2 for all other H atoms. In the absence of significant anomalous scattering, Friedel pairs were merged and the absolute configuration is arbitrary.

Structure description top

The title compound, 5α-hydroxyeudesm-4(15),11 (13)-dien-8β,12-olide (Fig.1), was isolated from the medicinal plant Carpesium minus (Compositae). This plant has been used to reduce swelling, relieve pain and as a detoxifying agent. The compound was identified by NMR spectra, which were compared with the previous reports (Lee et al., 2002; Yang et al., 2002; Li et al., 2011). Herewith, we present its crystal structure.

The molecule of the title compound has three fused rings consisting of two six- and one five-membered rings (A/B/C). The A/B ring junction is trans-fused and B/C is cis-fused. The two cyclohexane rings have chair conformations with puckering parameters (Cremer & Pople,1975) Q = 0.571 (2) Å, θ = 175.7 (2)° and φ = 134 (4)° for the A ring and Q = 0.512 (2) Å, θ = 156.4 (2)° and φ = 344.9 (6)° for the B ring; the cyclopentane ring adopts a twist conformation with puckering parameters Q = 0.258 (2) Å and φ = 237.1 (4)°. In the crystal, the molecules are linked into chains by intermolecular O—H···O hydrogen bonds.

For the isolation and biological activity of the title compound, see: Lee et al. (2002); Yang et al. (2002); Li et al. (2011). For conformational analysis, see: Cremer & Pople (1975).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); 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).

Figures top
[Figure 1] Fig. 1. The molecular structure of the compound, with atom labels and 50% probability displacement ellipsoids.
5α-Hydroxyeudesm-4(15),11 (13)-dien-8β,12-olide top
Crystal data top
C15H20O3F(000) = 268
Mr = 248.31Dx = 1.244 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
a = 7.893 (2) ÅCell parameters from 1583 reflections
b = 7.034 (2) Åθ = 2.9–23.8°
c = 12.166 (4) ŵ = 0.09 mm1
β = 101.154 (3)°T = 296 K
V = 662.7 (3) Å3Block, colorless
Z = 20.23 × 0.20 × 0.19 mm
Data collection top
Bruker APEXII CCD
diffractometer
1323 independent reflections
Radiation source: fine-focus sealed tube1159 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
φ and ω scansθmax = 25.5°, θmin = 2.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2006)
h = 99
Tmin = 0.981, Tmax = 0.984k = 87
3673 measured reflectionsl = 1314
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)] = 0.036Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.084H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.046P)2 + 0.026P]
where P = (Fo2 + 2Fc2)/3
1323 reflections(Δ/σ)max < 0.001
165 parametersΔρmax = 0.12 e Å3
1 restraintΔρmin = 0.17 e Å3
Crystal data top
C15H20O3V = 662.7 (3) Å3
Mr = 248.31Z = 2
Monoclinic, P21Mo Kα radiation
a = 7.893 (2) ŵ = 0.09 mm1
b = 7.034 (2) ÅT = 296 K
c = 12.166 (4) Å0.23 × 0.20 × 0.19 mm
β = 101.154 (3)°
Data collection top
Bruker APEXII CCD
diffractometer
1323 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2006)
1159 reflections with I > 2σ(I)
Tmin = 0.981, Tmax = 0.984Rint = 0.024
3673 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0361 restraint
wR(F2) = 0.084H-atom parameters constrained
S = 1.08Δρmax = 0.12 e Å3
1323 reflectionsΔρmin = 0.17 e Å3
165 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
C10.5831 (3)0.5040 (4)0.2805 (2)0.0451 (6)
H10.58430.64320.28440.054*
C20.6238 (3)0.4471 (4)0.1686 (2)0.0462 (6)
H2A0.70880.53530.15040.055*
H2B0.51970.46180.11200.055*
C30.6920 (3)0.2446 (4)0.16056 (19)0.0404 (6)
C40.7625 (4)0.2265 (4)0.0514 (2)0.0534 (7)
H4A0.66770.24210.01180.064*
H4B0.84420.32850.04860.064*
C50.8506 (4)0.0380 (5)0.0400 (2)0.0663 (9)
H5A0.89980.03960.02720.080*
H5B0.76600.06350.03250.080*
C60.9931 (4)0.0002 (5)0.1417 (2)0.0619 (8)
H6A1.03840.12750.13670.074*
H6B1.08680.08930.14250.074*
C70.9243 (3)0.0189 (4)0.2486 (2)0.0428 (6)
C80.8428 (3)0.2111 (3)0.26178 (18)0.0370 (5)
C90.7793 (3)0.2326 (3)0.37155 (18)0.0364 (5)
H9A0.87530.21090.43320.044*
H9B0.69310.13570.37520.044*
C100.7006 (3)0.4286 (3)0.38653 (18)0.0391 (5)
H100.79210.52080.41420.047*
C110.5786 (3)0.4143 (3)0.46605 (19)0.0397 (5)
C120.4025 (3)0.4029 (3)0.3975 (2)0.0439 (6)
C130.5451 (3)0.0994 (4)0.1587 (2)0.0491 (6)
H13A0.46070.11470.09100.074*
H13B0.49170.12020.22220.074*
H13C0.59150.02710.16180.074*
C140.9291 (3)0.1238 (4)0.3199 (2)0.0514 (6)
H14A0.97590.24010.30490.062*
H14B0.88570.10790.38520.062*
C150.6070 (3)0.4053 (4)0.5758 (2)0.0516 (7)
H15A0.51490.39130.61270.062*
H15B0.71920.41280.61680.062*
O10.9648 (2)0.3595 (3)0.25349 (15)0.0503 (5)
H1A1.05150.34450.30210.075*
O20.40859 (19)0.4391 (3)0.28997 (13)0.0530 (5)
O30.2681 (2)0.3667 (3)0.42676 (14)0.0585 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0446 (14)0.0397 (13)0.0508 (14)0.0042 (11)0.0082 (11)0.0056 (12)
C20.0434 (13)0.0513 (15)0.0420 (13)0.0031 (12)0.0038 (10)0.0127 (12)
C30.0365 (12)0.0485 (15)0.0358 (12)0.0004 (11)0.0058 (10)0.0046 (11)
C40.0549 (15)0.0681 (19)0.0381 (13)0.0003 (15)0.0112 (11)0.0055 (13)
C50.0695 (19)0.083 (2)0.0496 (16)0.0125 (18)0.0210 (14)0.0051 (15)
C60.0571 (17)0.072 (2)0.0608 (17)0.0137 (15)0.0213 (14)0.0028 (15)
C70.0332 (12)0.0468 (14)0.0473 (14)0.0009 (11)0.0050 (10)0.0027 (12)
C80.0299 (11)0.0393 (12)0.0405 (12)0.0064 (10)0.0037 (9)0.0032 (10)
C90.0331 (12)0.0388 (13)0.0346 (12)0.0009 (10)0.0001 (9)0.0001 (10)
C100.0360 (12)0.0373 (13)0.0421 (12)0.0046 (11)0.0030 (9)0.0010 (11)
C110.0380 (12)0.0347 (12)0.0463 (13)0.0018 (11)0.0077 (10)0.0058 (10)
C120.0395 (13)0.0425 (14)0.0491 (14)0.0017 (11)0.0076 (10)0.0060 (11)
C130.0422 (14)0.0570 (16)0.0447 (14)0.0085 (12)0.0003 (11)0.0044 (12)
C140.0465 (14)0.0438 (15)0.0634 (16)0.0054 (12)0.0096 (12)0.0006 (13)
C150.0537 (15)0.0541 (16)0.0471 (15)0.0042 (13)0.0099 (11)0.0043 (12)
O10.0357 (9)0.0532 (11)0.0608 (11)0.0118 (8)0.0062 (7)0.0067 (9)
O20.0357 (9)0.0746 (13)0.0470 (10)0.0067 (9)0.0036 (7)0.0005 (9)
O30.0364 (9)0.0772 (13)0.0632 (11)0.0042 (9)0.0130 (8)0.0094 (10)
Geometric parameters (Å, º) top
C1—O21.476 (3)C7—C81.519 (3)
C1—C21.512 (3)C8—O11.437 (3)
C1—C101.531 (3)C8—C91.522 (3)
C1—H10.9800C9—C101.538 (3)
C2—C31.533 (4)C9—H9A0.9700
C2—H2A0.9700C9—H9B0.9700
C2—H2B0.9700C10—C111.495 (3)
C3—C41.541 (3)C10—H100.9800
C3—C131.542 (3)C11—C151.312 (3)
C3—C81.556 (3)C11—C121.478 (3)
C4—C51.516 (4)C12—O31.210 (3)
C4—H4A0.9700C12—O21.342 (3)
C4—H4B0.9700C13—H13A0.9600
C5—C61.526 (4)C13—H13B0.9600
C5—H5A0.9700C13—H13C0.9600
C5—H5B0.9700C14—H14A0.9300
C6—C71.509 (3)C14—H14B0.9300
C6—H6A0.9700C15—H15A0.9300
C6—H6B0.9700C15—H15B0.9300
C7—C141.323 (4)O1—H1A0.8200
O2—C1—C2110.7 (2)O1—C8—C7109.61 (18)
O2—C1—C10104.44 (17)O1—C8—C9109.18 (19)
C2—C1—C10117.9 (2)C7—C8—C9113.54 (19)
O2—C1—H1107.8O1—C8—C3104.78 (17)
C2—C1—H1107.8C7—C8—C3109.00 (19)
C10—C1—H1107.8C9—C8—C3110.37 (17)
C1—C2—C3116.2 (2)C8—C9—C10113.71 (18)
C1—C2—H2A108.2C8—C9—H9A108.8
C3—C2—H2A108.2C10—C9—H9A108.8
C1—C2—H2B108.2C8—C9—H9B108.8
C3—C2—H2B108.2C10—C9—H9B108.8
H2A—C2—H2B107.4H9A—C9—H9B107.7
C2—C3—C4108.73 (19)C11—C10—C1101.97 (17)
C2—C3—C13110.1 (2)C11—C10—C9109.97 (19)
C4—C3—C13109.2 (2)C1—C10—C9113.80 (19)
C2—C3—C8108.32 (19)C11—C10—H10110.3
C4—C3—C8108.73 (18)C1—C10—H10110.3
C13—C3—C8111.67 (18)C9—C10—H10110.3
C5—C4—C3113.5 (2)C15—C11—C12121.9 (2)
C5—C4—H4A108.9C15—C11—C10131.1 (2)
C3—C4—H4A108.9C12—C11—C10106.96 (19)
C5—C4—H4B108.9O3—C12—O2121.7 (2)
C3—C4—H4B108.9O3—C12—C11128.9 (2)
H4A—C4—H4B107.7O2—C12—C11109.43 (19)
C4—C5—C6111.1 (3)C3—C13—H13A109.5
C4—C5—H5A109.4C3—C13—H13B109.5
C6—C5—H5A109.4H13A—C13—H13B109.5
C4—C5—H5B109.4C3—C13—H13C109.5
C6—C5—H5B109.4H13A—C13—H13C109.5
H5A—C5—H5B108.0H13B—C13—H13C109.5
C7—C6—C5110.5 (2)C7—C14—H14A120.0
C7—C6—H6A109.5C7—C14—H14B120.0
C5—C6—H6A109.5H14A—C14—H14B120.0
C7—C6—H6B109.5C11—C15—H15A120.0
C5—C6—H6B109.5C11—C15—H15B120.0
H6A—C6—H6B108.1H15A—C15—H15B120.0
C14—C7—C6121.9 (2)C8—O1—H1A109.5
C14—C7—C8124.4 (2)C12—O2—C1110.15 (17)
C6—C7—C8113.6 (2)
O2—C1—C2—C383.6 (3)C2—C3—C8—C960.6 (2)
C10—C1—C2—C336.5 (3)C4—C3—C8—C9178.6 (2)
C1—C2—C3—C4168.0 (2)C13—C3—C8—C960.9 (2)
C1—C2—C3—C1372.4 (3)O1—C8—C9—C1056.0 (2)
C1—C2—C3—C849.9 (3)C7—C8—C9—C10178.61 (18)
C2—C3—C4—C5174.0 (2)C3—C8—C9—C1058.7 (2)
C13—C3—C4—C565.8 (3)O2—C1—C10—C1126.1 (2)
C8—C3—C4—C556.2 (3)C2—C1—C10—C11149.3 (2)
C3—C4—C5—C654.6 (3)O2—C1—C10—C992.3 (2)
C4—C5—C6—C752.6 (3)C2—C1—C10—C931.0 (3)
C5—C6—C7—C14120.5 (3)C8—C9—C10—C11156.08 (18)
C5—C6—C7—C856.6 (3)C8—C9—C10—C142.4 (2)
C14—C7—C8—O1127.5 (3)C1—C10—C11—C15160.4 (3)
C6—C7—C8—O155.5 (3)C9—C10—C11—C1578.5 (3)
C14—C7—C8—C95.1 (3)C1—C10—C11—C1222.0 (2)
C6—C7—C8—C9177.9 (2)C9—C10—C11—C1299.1 (2)
C14—C7—C8—C3118.4 (3)C15—C11—C12—O37.9 (4)
C6—C7—C8—C358.6 (2)C10—C11—C12—O3170.0 (3)
C2—C3—C8—O156.8 (2)C15—C11—C12—O2172.5 (2)
C4—C3—C8—O161.2 (2)C10—C11—C12—O29.7 (3)
C13—C3—C8—O1178.3 (2)O3—C12—O2—C1172.3 (2)
C2—C3—C8—C7174.07 (19)C11—C12—O2—C18.1 (3)
C4—C3—C8—C756.1 (2)C2—C1—O2—C12149.8 (2)
C13—C3—C8—C764.5 (2)C10—C1—O2—C1222.0 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···O3i0.822.062.868 (2)168
Symmetry code: (i) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC15H20O3
Mr248.31
Crystal system, space groupMonoclinic, P21
Temperature (K)296
a, b, c (Å)7.893 (2), 7.034 (2), 12.166 (4)
β (°) 101.154 (3)
V3)662.7 (3)
Z2
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.23 × 0.20 × 0.19
Data collection
DiffractometerBruker APEXII CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2006)
Tmin, Tmax0.981, 0.984
No. of measured, independent and
observed [I > 2σ(I)] reflections
3673, 1323, 1159
Rint0.024
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.084, 1.08
No. of reflections1323
No. of parameters165
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.12, 0.17

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···O3i0.822.062.868 (2)168.2
Symmetry code: (i) x+1, y, z.
 

Acknowledgements

This work was supported by the Ministry of Education of Chongqing (grant No. KJ100719) and the Innovative Research Team Development Program of the University of Chongqing (grant No. KJTD201020).

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