organic compounds
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
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 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); Yang et al. (2002); Li et al. (2011). For see: Cremer & Pople (1975).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2006); cell SAINT (Bruker, 2006); data reduction: SAINT; 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.
Supporting information
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
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.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
Friedel pairs were merged and the is arbitrary.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 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.
-fused. The two cyclohexane rings have chair conformations with puckering parameters (Cremer & Pople,1975) Q = 0.571 (2) Å,For the isolation and biological activity of the title compound, see: Lee et al. (2002); Yang et al. (2002); Li et al. (2011). For
see: Cremer & Pople (1975).Data collection: APEX2 (Bruker, 2006); cell
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).Fig. 1. The molecular structure of the compound, with atom labels and 50% probability displacement ellipsoids. |
C15H20O3 | F(000) = 268 |
Mr = 248.31 | Dx = 1.244 Mg m−3 |
Monoclinic, P21 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.893 (2) Å | Cell parameters from 1583 reflections |
b = 7.034 (2) Å | θ = 2.9–23.8° |
c = 12.166 (4) Å | µ = 0.09 mm−1 |
β = 101.154 (3)° | T = 296 K |
V = 662.7 (3) Å3 | Block, colorless |
Z = 2 | 0.23 × 0.20 × 0.19 mm |
Bruker APEXII CCD diffractometer | 1323 independent reflections |
Radiation source: fine-focus sealed tube | 1159 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.024 |
φ and ω scans | θmax = 25.5°, θmin = 2.9° |
Absorption correction: multi-scan (SADABS; Bruker, 2006) | h = −9→9 |
Tmin = 0.981, Tmax = 0.984 | k = −8→7 |
3673 measured reflections | l = −13→14 |
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)] = 0.036 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.084 | H-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 parameters | Δρmax = 0.12 e Å−3 |
1 restraint | Δρmin = −0.17 e Å−3 |
C15H20O3 | V = 662.7 (3) Å3 |
Mr = 248.31 | Z = 2 |
Monoclinic, P21 | Mo Kα radiation |
a = 7.893 (2) Å | µ = 0.09 mm−1 |
b = 7.034 (2) Å | T = 296 K |
c = 12.166 (4) Å | 0.23 × 0.20 × 0.19 mm |
β = 101.154 (3)° |
Bruker APEXII CCD diffractometer | 1323 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2006) | 1159 reflections with I > 2σ(I) |
Tmin = 0.981, Tmax = 0.984 | Rint = 0.024 |
3673 measured reflections |
R[F2 > 2σ(F2)] = 0.036 | 1 restraint |
wR(F2) = 0.084 | H-atom parameters constrained |
S = 1.08 | Δρmax = 0.12 e Å−3 |
1323 reflections | Δρmin = −0.17 e Å−3 |
165 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.5831 (3) | 0.5040 (4) | 0.2805 (2) | 0.0451 (6) | |
H1 | 0.5843 | 0.6432 | 0.2844 | 0.054* | |
C2 | 0.6238 (3) | 0.4471 (4) | 0.1686 (2) | 0.0462 (6) | |
H2A | 0.7088 | 0.5353 | 0.1504 | 0.055* | |
H2B | 0.5197 | 0.4618 | 0.1120 | 0.055* | |
C3 | 0.6920 (3) | 0.2446 (4) | 0.16056 (19) | 0.0404 (6) | |
C4 | 0.7625 (4) | 0.2265 (4) | 0.0514 (2) | 0.0534 (7) | |
H4A | 0.6677 | 0.2421 | −0.0118 | 0.064* | |
H4B | 0.8442 | 0.3285 | 0.0486 | 0.064* | |
C5 | 0.8506 (4) | 0.0380 (5) | 0.0400 (2) | 0.0663 (9) | |
H5A | 0.8998 | 0.0396 | −0.0272 | 0.080* | |
H5B | 0.7660 | −0.0635 | 0.0325 | 0.080* | |
C6 | 0.9931 (4) | −0.0002 (5) | 0.1417 (2) | 0.0619 (8) | |
H6A | 1.0384 | −0.1275 | 0.1367 | 0.074* | |
H6B | 1.0868 | 0.0893 | 0.1425 | 0.074* | |
C7 | 0.9243 (3) | 0.0189 (4) | 0.2486 (2) | 0.0428 (6) | |
C8 | 0.8428 (3) | 0.2111 (3) | 0.26178 (18) | 0.0370 (5) | |
C9 | 0.7793 (3) | 0.2326 (3) | 0.37155 (18) | 0.0364 (5) | |
H9A | 0.8753 | 0.2109 | 0.4332 | 0.044* | |
H9B | 0.6931 | 0.1357 | 0.3752 | 0.044* | |
C10 | 0.7006 (3) | 0.4286 (3) | 0.38653 (18) | 0.0391 (5) | |
H10 | 0.7921 | 0.5208 | 0.4142 | 0.047* | |
C11 | 0.5786 (3) | 0.4143 (3) | 0.46605 (19) | 0.0397 (5) | |
C12 | 0.4025 (3) | 0.4029 (3) | 0.3975 (2) | 0.0439 (6) | |
C13 | 0.5451 (3) | 0.0994 (4) | 0.1587 (2) | 0.0491 (6) | |
H13A | 0.4607 | 0.1147 | 0.0910 | 0.074* | |
H13B | 0.4917 | 0.1202 | 0.2222 | 0.074* | |
H13C | 0.5915 | −0.0271 | 0.1618 | 0.074* | |
C14 | 0.9291 (3) | −0.1238 (4) | 0.3199 (2) | 0.0514 (6) | |
H14A | 0.9759 | −0.2401 | 0.3049 | 0.062* | |
H14B | 0.8857 | −0.1079 | 0.3852 | 0.062* | |
C15 | 0.6070 (3) | 0.4053 (4) | 0.5758 (2) | 0.0516 (7) | |
H15A | 0.5149 | 0.3913 | 0.6127 | 0.062* | |
H15B | 0.7192 | 0.4128 | 0.6168 | 0.062* | |
O1 | 0.9648 (2) | 0.3595 (3) | 0.25349 (15) | 0.0503 (5) | |
H1A | 1.0515 | 0.3445 | 0.3021 | 0.075* | |
O2 | 0.40859 (19) | 0.4391 (3) | 0.28997 (13) | 0.0530 (5) | |
O3 | 0.2681 (2) | 0.3667 (3) | 0.42676 (14) | 0.0585 (5) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0446 (14) | 0.0397 (13) | 0.0508 (14) | 0.0042 (11) | 0.0082 (11) | 0.0056 (12) |
C2 | 0.0434 (13) | 0.0513 (15) | 0.0420 (13) | 0.0031 (12) | 0.0038 (10) | 0.0127 (12) |
C3 | 0.0365 (12) | 0.0485 (15) | 0.0358 (12) | 0.0004 (11) | 0.0058 (10) | 0.0046 (11) |
C4 | 0.0549 (15) | 0.0681 (19) | 0.0381 (13) | 0.0003 (15) | 0.0112 (11) | 0.0055 (13) |
C5 | 0.0695 (19) | 0.083 (2) | 0.0496 (16) | 0.0125 (18) | 0.0210 (14) | −0.0051 (15) |
C6 | 0.0571 (17) | 0.072 (2) | 0.0608 (17) | 0.0137 (15) | 0.0213 (14) | −0.0028 (15) |
C7 | 0.0332 (12) | 0.0468 (14) | 0.0473 (14) | 0.0009 (11) | 0.0050 (10) | −0.0027 (12) |
C8 | 0.0299 (11) | 0.0393 (12) | 0.0405 (12) | −0.0064 (10) | 0.0037 (9) | 0.0032 (10) |
C9 | 0.0331 (12) | 0.0388 (13) | 0.0346 (12) | −0.0009 (10) | −0.0001 (9) | 0.0001 (10) |
C10 | 0.0360 (12) | 0.0373 (13) | 0.0421 (12) | −0.0046 (11) | 0.0030 (9) | −0.0010 (11) |
C11 | 0.0380 (12) | 0.0347 (12) | 0.0463 (13) | −0.0018 (11) | 0.0077 (10) | −0.0058 (10) |
C12 | 0.0395 (13) | 0.0425 (14) | 0.0491 (14) | 0.0017 (11) | 0.0076 (10) | −0.0060 (11) |
C13 | 0.0422 (14) | 0.0570 (16) | 0.0447 (14) | −0.0085 (12) | 0.0003 (11) | −0.0044 (12) |
C14 | 0.0465 (14) | 0.0438 (15) | 0.0634 (16) | 0.0054 (12) | 0.0096 (12) | −0.0006 (13) |
C15 | 0.0537 (15) | 0.0541 (16) | 0.0471 (15) | 0.0042 (13) | 0.0099 (11) | −0.0043 (12) |
O1 | 0.0357 (9) | 0.0532 (11) | 0.0608 (11) | −0.0118 (8) | 0.0062 (7) | 0.0067 (9) |
O2 | 0.0357 (9) | 0.0746 (13) | 0.0470 (10) | 0.0067 (9) | 0.0036 (7) | 0.0005 (9) |
O3 | 0.0364 (9) | 0.0772 (13) | 0.0632 (11) | −0.0042 (9) | 0.0130 (8) | −0.0094 (10) |
C1—O2 | 1.476 (3) | C7—C8 | 1.519 (3) |
C1—C2 | 1.512 (3) | C8—O1 | 1.437 (3) |
C1—C10 | 1.531 (3) | C8—C9 | 1.522 (3) |
C1—H1 | 0.9800 | C9—C10 | 1.538 (3) |
C2—C3 | 1.533 (4) | C9—H9A | 0.9700 |
C2—H2A | 0.9700 | C9—H9B | 0.9700 |
C2—H2B | 0.9700 | C10—C11 | 1.495 (3) |
C3—C4 | 1.541 (3) | C10—H10 | 0.9800 |
C3—C13 | 1.542 (3) | C11—C15 | 1.312 (3) |
C3—C8 | 1.556 (3) | C11—C12 | 1.478 (3) |
C4—C5 | 1.516 (4) | C12—O3 | 1.210 (3) |
C4—H4A | 0.9700 | C12—O2 | 1.342 (3) |
C4—H4B | 0.9700 | C13—H13A | 0.9600 |
C5—C6 | 1.526 (4) | C13—H13B | 0.9600 |
C5—H5A | 0.9700 | C13—H13C | 0.9600 |
C5—H5B | 0.9700 | C14—H14A | 0.9300 |
C6—C7 | 1.509 (3) | C14—H14B | 0.9300 |
C6—H6A | 0.9700 | C15—H15A | 0.9300 |
C6—H6B | 0.9700 | C15—H15B | 0.9300 |
C7—C14 | 1.323 (4) | O1—H1A | 0.8200 |
O2—C1—C2 | 110.7 (2) | O1—C8—C7 | 109.61 (18) |
O2—C1—C10 | 104.44 (17) | O1—C8—C9 | 109.18 (19) |
C2—C1—C10 | 117.9 (2) | C7—C8—C9 | 113.54 (19) |
O2—C1—H1 | 107.8 | O1—C8—C3 | 104.78 (17) |
C2—C1—H1 | 107.8 | C7—C8—C3 | 109.00 (19) |
C10—C1—H1 | 107.8 | C9—C8—C3 | 110.37 (17) |
C1—C2—C3 | 116.2 (2) | C8—C9—C10 | 113.71 (18) |
C1—C2—H2A | 108.2 | C8—C9—H9A | 108.8 |
C3—C2—H2A | 108.2 | C10—C9—H9A | 108.8 |
C1—C2—H2B | 108.2 | C8—C9—H9B | 108.8 |
C3—C2—H2B | 108.2 | C10—C9—H9B | 108.8 |
H2A—C2—H2B | 107.4 | H9A—C9—H9B | 107.7 |
C2—C3—C4 | 108.73 (19) | C11—C10—C1 | 101.97 (17) |
C2—C3—C13 | 110.1 (2) | C11—C10—C9 | 109.97 (19) |
C4—C3—C13 | 109.2 (2) | C1—C10—C9 | 113.80 (19) |
C2—C3—C8 | 108.32 (19) | C11—C10—H10 | 110.3 |
C4—C3—C8 | 108.73 (18) | C1—C10—H10 | 110.3 |
C13—C3—C8 | 111.67 (18) | C9—C10—H10 | 110.3 |
C5—C4—C3 | 113.5 (2) | C15—C11—C12 | 121.9 (2) |
C5—C4—H4A | 108.9 | C15—C11—C10 | 131.1 (2) |
C3—C4—H4A | 108.9 | C12—C11—C10 | 106.96 (19) |
C5—C4—H4B | 108.9 | O3—C12—O2 | 121.7 (2) |
C3—C4—H4B | 108.9 | O3—C12—C11 | 128.9 (2) |
H4A—C4—H4B | 107.7 | O2—C12—C11 | 109.43 (19) |
C4—C5—C6 | 111.1 (3) | C3—C13—H13A | 109.5 |
C4—C5—H5A | 109.4 | C3—C13—H13B | 109.5 |
C6—C5—H5A | 109.4 | H13A—C13—H13B | 109.5 |
C4—C5—H5B | 109.4 | C3—C13—H13C | 109.5 |
C6—C5—H5B | 109.4 | H13A—C13—H13C | 109.5 |
H5A—C5—H5B | 108.0 | H13B—C13—H13C | 109.5 |
C7—C6—C5 | 110.5 (2) | C7—C14—H14A | 120.0 |
C7—C6—H6A | 109.5 | C7—C14—H14B | 120.0 |
C5—C6—H6A | 109.5 | H14A—C14—H14B | 120.0 |
C7—C6—H6B | 109.5 | C11—C15—H15A | 120.0 |
C5—C6—H6B | 109.5 | C11—C15—H15B | 120.0 |
H6A—C6—H6B | 108.1 | H15A—C15—H15B | 120.0 |
C14—C7—C6 | 121.9 (2) | C8—O1—H1A | 109.5 |
C14—C7—C8 | 124.4 (2) | C12—O2—C1 | 110.15 (17) |
C6—C7—C8 | 113.6 (2) | ||
O2—C1—C2—C3 | −83.6 (3) | C2—C3—C8—C9 | 60.6 (2) |
C10—C1—C2—C3 | 36.5 (3) | C4—C3—C8—C9 | 178.6 (2) |
C1—C2—C3—C4 | −168.0 (2) | C13—C3—C8—C9 | −60.9 (2) |
C1—C2—C3—C13 | 72.4 (3) | O1—C8—C9—C10 | 56.0 (2) |
C1—C2—C3—C8 | −49.9 (3) | C7—C8—C9—C10 | 178.61 (18) |
C2—C3—C4—C5 | 174.0 (2) | C3—C8—C9—C10 | −58.7 (2) |
C13—C3—C4—C5 | −65.8 (3) | O2—C1—C10—C11 | −26.1 (2) |
C8—C3—C4—C5 | 56.2 (3) | C2—C1—C10—C11 | −149.3 (2) |
C3—C4—C5—C6 | −54.6 (3) | O2—C1—C10—C9 | 92.3 (2) |
C4—C5—C6—C7 | 52.6 (3) | C2—C1—C10—C9 | −31.0 (3) |
C5—C6—C7—C14 | 120.5 (3) | C8—C9—C10—C11 | 156.08 (18) |
C5—C6—C7—C8 | −56.6 (3) | C8—C9—C10—C1 | 42.4 (2) |
C14—C7—C8—O1 | 127.5 (3) | C1—C10—C11—C15 | −160.4 (3) |
C6—C7—C8—O1 | −55.5 (3) | C9—C10—C11—C15 | 78.5 (3) |
C14—C7—C8—C9 | 5.1 (3) | C1—C10—C11—C12 | 22.0 (2) |
C6—C7—C8—C9 | −177.9 (2) | C9—C10—C11—C12 | −99.1 (2) |
C14—C7—C8—C3 | −118.4 (3) | C15—C11—C12—O3 | −7.9 (4) |
C6—C7—C8—C3 | 58.6 (2) | C10—C11—C12—O3 | 170.0 (3) |
C2—C3—C8—O1 | −56.8 (2) | C15—C11—C12—O2 | 172.5 (2) |
C4—C3—C8—O1 | 61.2 (2) | C10—C11—C12—O2 | −9.7 (3) |
C13—C3—C8—O1 | −178.3 (2) | O3—C12—O2—C1 | 172.3 (2) |
C2—C3—C8—C7 | −174.07 (19) | C11—C12—O2—C1 | −8.1 (3) |
C4—C3—C8—C7 | −56.1 (2) | C2—C1—O2—C12 | 149.8 (2) |
C13—C3—C8—C7 | 64.5 (2) | C10—C1—O2—C12 | 22.0 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1A···O3i | 0.82 | 2.06 | 2.868 (2) | 168 |
Symmetry code: (i) x+1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C15H20O3 |
Mr | 248.31 |
Crystal system, space group | Monoclinic, P21 |
Temperature (K) | 296 |
a, b, c (Å) | 7.893 (2), 7.034 (2), 12.166 (4) |
β (°) | 101.154 (3) |
V (Å3) | 662.7 (3) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.23 × 0.20 × 0.19 |
Data collection | |
Diffractometer | Bruker APEXII CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2006) |
Tmin, Tmax | 0.981, 0.984 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3673, 1323, 1159 |
Rint | 0.024 |
(sin θ/λ)max (Å−1) | 0.606 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.036, 0.084, 1.08 |
No. of reflections | 1323 |
No. of parameters | 165 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.12, −0.17 |
Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1A···O3i | 0.82 | 2.06 | 2.868 (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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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.