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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 2| February 2012| Pages o520-o521

ent-(15S)-Pimar-8(14)-ene-15,16-diol

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, bCrystal Materials Research Unit, Department of Chemistry, Faculty of Science, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand, cDepartment of Chemistry, Faculty of Science, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand, and dResearch Unit of Natural Products Utilization, Walailak University, Thasala, Nakhon Si Thammarat 80160, Thailand
*Correspondence e-mail: hkfun@usm.my

(Received 17 January 2012; accepted 20 January 2012; online 25 January 2012)

The title compound {systematic name: (S)-1-[(2S,4aR,8aR)-2,4b,8,8-tetra­methyl-2,3,4,4a,4b,5,6,7,8,8a,9,10-dodeca­hydro­phenanthren-2-yl]ethane-1,2-diol}, C20H34O2, is an ent-pimarane diterpenoid which was isolated from the stem bark of Ceriops tagal. In the asymmetric unit, there are two crystallographically independent mol­ecules, which are conformationally almost identical. In each mol­ecule, the two cyclo­hexane rings of the fused three-ring system adopt chair conformations, while the cyclo­hexene ring is in an envelope conformation, with the methylene C atom next to the side chain as the flap atom. In the crystal, mol­ecules are stacked in columns along the b axis through O—H⋯O hydrogen bonds.

Related literature

For ring conformations, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]). For standard bond lengths, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For bioactive compounds from Ceriops tagal and their activities, see: Bamroongrugsa (1999[Bamroongrugsa, N. (1999). Songklanakarin J. Sci. Technol. 21, 377-386.]); Chacha (2011[Chacha, M. (2011). Int. J. Biol. Chem. Sci. 5, 402-409.]); Pakhathirathien et al. (2005[Pakhathirathien, C., Karalai, C., Ponglimanont, C., Subhadhirasakul, S. & Chantrapromma, K. (2005). J. Nat. Prod. 68, 1787-1789.]); Zhang et al. (2005[Zhang, Y., Deng, Z., Gao, T., Proksch, P. & Lin, W. (2005). Phytochemistry, 66, 1465-1471.]). For related structures, see: Chantrapromma et al. (2007[Chantrapromma, S., Fun, H.-K., Pakhathirathien, C., Karalai, C. & Chantrapromma, K. (2007). Acta Cryst. E63, o459-o461.]); Fun et al. (2006[Fun, H.-K., Pakhathirathien, C., Chantrapromma, S., Karalai, C. & Chantrapromma, K. (2006). Acta Cryst. E62, o5539-o5541.], 2010[Fun, H.-K., Pakathirathien, C., Karalai, C. & Chantrapromma, S. (2010). Acta Cryst. E66, o2897-o2898.]).

[Scheme 1]

Experimental

Crystal data
  • C20H34O2

  • Mr = 306.47

  • Monoclinic, P 21

  • a = 11.5129 (2) Å

  • b = 7.0934 (1) Å

  • c = 22.3946 (4) Å

  • β = 96.750 (1)°

  • V = 1816.19 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.07 mm−1

  • T = 273 K

  • 0.56 × 0.34 × 0.25 mm

Data collection
  • Bruker SMART APEX2 CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.962, Tmax = 0.983

  • 28246 measured reflections

  • 5205 independent reflections

  • 4504 reflections with I > 2σ(I)

  • Rint = 0.031

Refinement
  • R[F2 > 2σ(F2)] = 0.041

  • wR(F2) = 0.106

  • S = 1.03

  • 5205 reflections

  • 421 parameters

  • 1 restraint

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

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.16 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1A—H1OA⋯O1Bi 0.78 (3) 2.06 (3) 2.839 (2) 174 (3)
O2A—H1OB⋯O1Bi 0.84 (4) 2.14 (4) 2.931 (2) 158 (3)
O1B—H1OC⋯O2Bii 0.76 (2) 1.96 (2) 2.719 (2) 178 (3)
O2B—H1OD⋯O1Aiii 0.77 (3) 2.13 (3) 2.795 (3) 145 (3)
Symmetry codes: (i) x+1, y, z; (ii) [-x, y+{\script{1\over 2}}, -z]; (iii) x-1, y-1, z.

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Diterpenoids and triterpenoids are the main secondary metabolites of Ceriops tagal (Chacha, 2011; Pakhathirathien et al., 2005; Zhang et al., 2005). The decoction of this mangrove plant was used as substitute for quinine as treatment for Malaria and the bark has been used for the treatment of infected wounds (Bamroongrugsa, 1999). During the course of our studies on the chemical constituents and bioactive compounds from Thai medicinal plants, the title compound (I) which is a new ent pimarane diterpenoid, named as "Ceriotagalsin A", was isolated from the stem bark of C. tagal. We have also previously reported the crystal structures of diterpenoids isolated from the same plant (Chantrapromma et al., 2007; Fun et al., 2006, 2010). (I) was tested for antimalarial activity and found to be inactive. We herein report the crystal structure of (I).

The title compound (I) (Fig. 1) crystallized out with two crystallographically independent molecules A and B per asymmetric unit with slight differences in bond angles. The molecule of (I) contains a fused three-ring system A/B/C (Fig. 1). The A/B ring junction is trans-fused. In both molecules, the cyclohexane ring A and B have standard chair conformations (Cremer & Pople 1975). The cyclohexene ring C adopts an envelope conformation with the puckered C13 atom having the maximum deviation of 0.335 (2) Å and puckering parameters Q = 0.481 (2) Å, θ = 125.7 (2)° and ϕ = 347.9 (3)° in molecule A [the corresponding values are -0.329 (2) Å, Q = 0.465 (2) Å, θ = 54.8 (2)° and ϕ = 177.1 (3)° in molecule B]. The 1,2-hydroxyethyl is bisectionally attached to the cyclohexene ring at atom C12 with the torsion angle C11—C12—C15—O1 = -47.6 (2)° and C12—C15—C16—O2 = -162.28 (18)° in molecule A [the corresponding values are -176.96 (13) and -161.55 (17)° in molecule B]. The C8C11 bond length [1.326 (3) Å in molecule A and 1.328 (2) Å in molecule B] and bond angles around atoms C8 and C11 indicate the sp2 hybridization for these atoms. The bond distances are of normal values (Allen et al., 1987) and are comparable with the related structures (Chantrapromma et al., 2007; Fun et al., 2006, 2010).

In the crystal structure (Fig. 2), the molecules are linked into one dimensional screw chains along the [0 1 0] direction. The crystal packing is stabilized by intermolecular O—H···O hydrogen bonds (Table 1).

Related literature top

For ring conformations, see: Cremer & Pople (1975). For standard bond lengths, see: Allen et al. (1987). For bioactive compounds from Ceriops tagal and their activities, see: Bamroongrugsa (1999); Chacha (2011); Pakhathirathien et al. (2005); Zhang et al. (2005). For related structures, see: Chantrapromma et al. (2007); Fun et al. (2006, 2010).

Experimental top

The air-dried and crushed stem bark of C. tagal (4.8 kg) were extracted with methylene chloride and then concentrated in vacuo to give a residue (17.4 g). This residue was subjected to quick column chromatography over silica gel using solvents of increasing polarity from hexane through 50% acetone/hexane. The eluates were collected and combined based on TLC to give 20 fractions (F1—F20). Fraction F14 was further purified by repeated quick column chromatography with CH2Cl2/acetone (9:1 v/v) yielding the title compound (30.1 mg). Colorless needle-shaped single crystals of the title compound suitable for x-ray structure determination were recrystallized from acetone after several days (m.p. 377–378 K).

Refinement top

Hydroxy H atoms were located from the difference maps and freely refined [refined O—H distances 0.76 (2)–0.84 (4) Å]. The remaining H atoms were placed in calculated positions with C—H = 0.93 Å for aromatic, 0.98 Å for CH, 0.97 Å for CH2 and 0.96 Å for CH3 atoms. The Uiso(H) values were constrained to be 1.5Ueq of the carrier atom for methyl H atoms and 1.2Ueq for the remaining H atoms. A rotating group model was used for the methyl groups. A total of 3692 Friedel pairs were merged before final refinement as there is no large anomalous dispersion for the determination of the absolute configuration.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the title compound, showing 30% probability displacement ellipsoids and the atom-numbering scheme.
[Figure 2] Fig. 2. A packing diagram of the title compound viewed along the c axis, showing screw chains running along the [0 1 0] direction. For clarity, H atoms not involved in hydrogen bonds were omitted. Hydrogen bonds are shown as dashed lines.
(S)-1-[(2S,4aR,8aR)-2,4b,8,8-tetramethyl- 2,3,4,4a,4b,5,6,7,8,8a,9,10-dodecahydrophenanthren-2-yl]ethane-1,2-diol top
Crystal data top
C20H34O2F(000) = 680
Mr = 306.47Dx = 1.121 Mg m3
Monoclinic, P21Melting point = 377–378 K
Hall symbol: P 2ybMo Kα radiation, λ = 0.71073 Å
a = 11.5129 (2) ÅCell parameters from 5205 reflections
b = 7.0934 (1) Åθ = 1.8–29.0°
c = 22.3946 (4) ŵ = 0.07 mm1
β = 96.750 (1)°T = 273 K
V = 1816.19 (5) Å3Needle, colorless
Z = 40.56 × 0.34 × 0.25 mm
Data collection top
Bruker SMART APEX2 CCD area-detector
diffractometer
5205 independent reflections
Radiation source: fine-focus sealed tube4504 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.031
Detector resolution: 8.33 pixels mm-1θmax = 29.0°, θmin = 1.8°
ω scansh = 1515
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
k = 99
Tmin = 0.962, Tmax = 0.983l = 3030
28246 measured reflections
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)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.106H atoms treated by a mixture of independent and constrained refinement
S = 1.03 w = 1/[σ2(Fo2) + (0.0565P)2 + 0.1315P]
where P = (Fo2 + 2Fc2)/3
5205 reflections(Δ/σ)max = 0.001
421 parametersΔρmax = 0.17 e Å3
1 restraintΔρmin = 0.16 e Å3
Crystal data top
C20H34O2V = 1816.19 (5) Å3
Mr = 306.47Z = 4
Monoclinic, P21Mo Kα radiation
a = 11.5129 (2) ŵ = 0.07 mm1
b = 7.0934 (1) ÅT = 273 K
c = 22.3946 (4) Å0.56 × 0.34 × 0.25 mm
β = 96.750 (1)°
Data collection top
Bruker SMART APEX2 CCD area-detector
diffractometer
5205 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
4504 reflections with I > 2σ(I)
Tmin = 0.962, Tmax = 0.983Rint = 0.031
28246 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0411 restraint
wR(F2) = 0.106H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.17 e Å3
5205 reflectionsΔρmin = 0.16 e Å3
421 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
O1A0.81903 (14)0.4262 (2)0.07420 (7)0.0536 (4)
H1OA0.866 (2)0.351 (4)0.0679 (11)0.058 (8)*
O2A0.73660 (18)0.0232 (3)0.05561 (9)0.0749 (5)
H1OB0.799 (3)0.052 (6)0.0421 (14)0.098 (11)*
C1A0.72183 (17)0.3489 (3)0.35428 (8)0.0472 (4)
H1AA0.64770.40360.36170.057*
H1AB0.70590.22590.33620.057*
C2A0.7980 (2)0.3239 (3)0.41415 (10)0.0562 (5)
H2AA0.75710.24680.44070.067*
H2AB0.86980.25950.40760.067*
C3A0.82712 (19)0.5136 (4)0.44337 (9)0.0527 (5)
H3AA0.87530.49380.48140.063*
H3AB0.75520.57370.45190.063*
C4A0.89149 (16)0.6458 (3)0.40430 (9)0.0447 (4)
C5A0.81852 (14)0.6626 (3)0.34104 (8)0.0361 (4)
H5AA0.74600.72560.34880.043*
C6A0.87199 (17)0.7930 (3)0.29730 (9)0.0455 (4)
H6AA0.89760.90890.31770.055*
H6AB0.93980.73270.28370.055*
C7A0.78277 (18)0.8383 (3)0.24320 (9)0.0465 (4)
H7AA0.72240.91880.25620.056*
H7AB0.82140.90800.21390.056*
C8A0.72631 (15)0.6656 (3)0.21346 (8)0.0390 (4)
C9A0.68153 (13)0.5262 (3)0.25669 (8)0.0364 (4)
H9AA0.61970.59170.27510.044*
C10A0.77758 (14)0.4746 (3)0.30945 (8)0.0352 (4)
C11A0.71179 (15)0.6440 (3)0.15422 (9)0.0427 (4)
H11A0.74720.73240.13160.051*
C12A0.64268 (14)0.4882 (3)0.12021 (8)0.0431 (4)
C13A0.56019 (15)0.4038 (4)0.16287 (9)0.0495 (5)
H13A0.49860.49380.16780.059*
H13B0.52380.29100.14470.059*
C14A0.62334 (16)0.3544 (3)0.22433 (8)0.0455 (4)
H14A0.68250.26000.21960.055*
H14B0.56780.30030.24890.055*
C15A0.72612 (15)0.3356 (3)0.10103 (8)0.0409 (4)
H15A0.76090.27060.13740.049*
C16A0.6687 (2)0.1888 (4)0.05847 (12)0.0647 (7)
H16A0.59370.15510.07110.078*
H16B0.65410.24300.01850.078*
C17A0.5698 (2)0.5755 (4)0.06543 (11)0.0661 (7)
H17A0.52550.67970.07810.099*
H17B0.51750.48230.04640.099*
H17C0.62090.61920.03740.099*
C18A0.8966 (2)0.8406 (4)0.43453 (11)0.0639 (6)
H18A0.92670.82780.47620.096*
H18B0.81940.89360.43140.096*
H18C0.94680.92200.41490.096*
C19A1.01865 (16)0.5797 (4)0.40298 (11)0.0591 (6)
H19A1.06280.60360.44130.089*
H19B1.05290.64720.37230.089*
H19C1.01950.44700.39450.089*
C20A0.87771 (16)0.3679 (3)0.28404 (9)0.0456 (4)
H20A0.85250.24220.27310.068*
H20B0.94440.36230.31400.068*
H20C0.89850.43260.24920.068*
O1B0.02356 (11)0.1434 (3)0.04385 (6)0.0461 (3)
H1OC0.008 (2)0.172 (4)0.0131 (10)0.048 (6)*
O2B0.03925 (16)0.2575 (3)0.06519 (7)0.0609 (5)
H1OD0.082 (2)0.320 (5)0.0804 (12)0.068 (9)*
C1B0.27744 (18)0.3103 (3)0.34629 (8)0.0460 (4)
H1BA0.34260.39060.33920.055*
H1BB0.20600.38150.33580.055*
C2B0.2877 (2)0.2604 (4)0.41295 (9)0.0555 (5)
H2BA0.28850.37500.43660.067*
H2BB0.22060.18600.42100.067*
C3B0.39891 (19)0.1496 (4)0.43098 (9)0.0512 (5)
H3BA0.40280.11790.47330.061*
H3BB0.46550.22940.42590.061*
C4B0.40886 (15)0.0322 (3)0.39499 (8)0.0413 (4)
C5B0.38623 (13)0.0151 (3)0.32653 (7)0.0346 (4)
H5BA0.45260.09440.31900.041*
C6B0.39381 (17)0.1555 (3)0.28551 (8)0.0463 (4)
H6BA0.32380.23180.28540.056*
H6BB0.46060.23240.30050.056*
C7B0.40626 (16)0.0902 (4)0.22146 (8)0.0497 (5)
H7BA0.48140.02870.22090.060*
H7BB0.40440.19920.19520.060*
C8B0.31058 (14)0.0438 (3)0.19795 (8)0.0387 (4)
C9B0.28974 (14)0.2057 (3)0.23949 (7)0.0352 (4)
H9BA0.36230.27930.24330.042*
C10B0.27621 (13)0.1366 (3)0.30492 (7)0.0325 (3)
C11B0.25326 (14)0.0238 (3)0.14331 (8)0.0425 (4)
H11B0.27410.07770.12050.051*
C12B0.15718 (15)0.1514 (3)0.11489 (7)0.0399 (4)
C13B0.10155 (15)0.2509 (3)0.16542 (8)0.0441 (4)
H13C0.04790.34700.14810.053*
H13D0.05700.16000.18570.053*
C14B0.19380 (16)0.3423 (3)0.21132 (8)0.0447 (4)
H14C0.15480.39700.24330.054*
H14D0.23090.44420.19180.054*
C15B0.06752 (14)0.0294 (3)0.07492 (7)0.0395 (4)
H15B0.10920.03180.04450.047*
C16B0.00925 (17)0.1240 (3)0.10784 (8)0.0461 (5)
H16C0.06620.18440.13710.055*
H16D0.05170.07020.12900.055*
C17B0.20945 (19)0.2949 (4)0.07418 (9)0.0586 (6)
H17D0.27010.36530.09740.088*
H17E0.14930.37950.05730.088*
H17F0.24170.22970.04240.088*
C18B0.53511 (17)0.1040 (4)0.40919 (9)0.0621 (7)
H18D0.55660.10410.45190.093*
H18E0.58700.02280.39050.093*
H18F0.54050.22980.39400.093*
C19B0.3277 (2)0.1827 (4)0.41623 (10)0.0555 (5)
H19D0.35600.22010.45650.083*
H19E0.32610.29010.39010.083*
H19F0.25020.13210.41540.083*
C20B0.15986 (14)0.0313 (3)0.30453 (9)0.0454 (4)
H20D0.09650.11420.29060.068*
H20E0.15110.01070.34450.068*
H20F0.15910.07560.27820.068*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O1A0.0549 (8)0.0457 (9)0.0638 (9)0.0041 (8)0.0218 (7)0.0016 (8)
O2A0.0815 (11)0.0496 (10)0.0990 (13)0.0137 (10)0.0331 (11)0.0231 (11)
C1A0.0553 (10)0.0372 (10)0.0509 (10)0.0109 (10)0.0145 (8)0.0010 (9)
C2A0.0703 (13)0.0434 (12)0.0564 (11)0.0039 (11)0.0137 (10)0.0121 (11)
C3A0.0581 (11)0.0529 (13)0.0469 (10)0.0006 (11)0.0058 (8)0.0020 (11)
C4A0.0439 (9)0.0376 (10)0.0517 (10)0.0007 (9)0.0021 (8)0.0016 (10)
C5A0.0340 (7)0.0274 (8)0.0473 (9)0.0018 (7)0.0066 (6)0.0033 (8)
C6A0.0479 (9)0.0310 (10)0.0577 (11)0.0080 (8)0.0067 (8)0.0015 (9)
C7A0.0602 (11)0.0268 (9)0.0532 (10)0.0034 (9)0.0099 (8)0.0031 (9)
C8A0.0390 (8)0.0295 (9)0.0491 (9)0.0024 (8)0.0073 (7)0.0006 (8)
C9A0.0303 (7)0.0331 (9)0.0471 (9)0.0006 (7)0.0102 (6)0.0030 (8)
C10A0.0343 (7)0.0273 (8)0.0455 (9)0.0001 (7)0.0113 (6)0.0024 (8)
C11A0.0437 (9)0.0339 (9)0.0507 (9)0.0014 (8)0.0069 (7)0.0024 (9)
C12A0.0379 (8)0.0448 (12)0.0456 (9)0.0032 (9)0.0001 (7)0.0011 (9)
C13A0.0351 (8)0.0549 (13)0.0581 (11)0.0048 (9)0.0045 (8)0.0099 (11)
C14A0.0430 (9)0.0434 (11)0.0521 (10)0.0132 (9)0.0140 (8)0.0035 (10)
C15A0.0402 (8)0.0411 (10)0.0412 (8)0.0031 (8)0.0041 (7)0.0015 (9)
C16A0.0555 (12)0.0631 (16)0.0754 (14)0.0099 (12)0.0068 (10)0.0270 (14)
C17A0.0615 (12)0.0682 (17)0.0641 (13)0.0125 (13)0.0117 (10)0.0059 (13)
C18A0.0765 (14)0.0499 (13)0.0617 (13)0.0019 (13)0.0064 (11)0.0132 (12)
C19A0.0420 (9)0.0623 (15)0.0706 (13)0.0028 (10)0.0044 (9)0.0069 (13)
C20A0.0431 (9)0.0330 (10)0.0620 (11)0.0074 (8)0.0122 (8)0.0042 (9)
O1B0.0411 (6)0.0602 (9)0.0366 (6)0.0013 (7)0.0030 (5)0.0069 (7)
O2B0.0763 (10)0.0602 (11)0.0493 (8)0.0274 (9)0.0203 (7)0.0137 (8)
C1B0.0599 (11)0.0365 (10)0.0416 (9)0.0044 (9)0.0061 (8)0.0042 (9)
C2B0.0817 (14)0.0440 (12)0.0420 (10)0.0066 (12)0.0118 (9)0.0094 (10)
C3B0.0639 (11)0.0495 (12)0.0391 (9)0.0073 (11)0.0011 (8)0.0005 (10)
C4B0.0418 (8)0.0426 (10)0.0393 (8)0.0012 (8)0.0039 (7)0.0053 (8)
C5B0.0291 (6)0.0368 (9)0.0379 (8)0.0017 (7)0.0043 (6)0.0018 (8)
C6B0.0465 (9)0.0423 (11)0.0495 (10)0.0166 (9)0.0032 (7)0.0044 (10)
C7B0.0431 (9)0.0617 (14)0.0445 (9)0.0198 (10)0.0056 (7)0.0100 (10)
C8B0.0343 (7)0.0434 (10)0.0391 (8)0.0039 (8)0.0080 (6)0.0028 (8)
C9B0.0323 (7)0.0359 (9)0.0370 (8)0.0008 (7)0.0023 (6)0.0029 (7)
C10B0.0295 (7)0.0306 (8)0.0377 (8)0.0011 (7)0.0052 (6)0.0026 (8)
C11B0.0408 (8)0.0483 (11)0.0392 (8)0.0044 (9)0.0080 (7)0.0071 (9)
C12B0.0410 (8)0.0448 (10)0.0335 (8)0.0022 (9)0.0024 (6)0.0000 (9)
C13B0.0420 (9)0.0459 (11)0.0427 (9)0.0100 (9)0.0029 (7)0.0031 (9)
C14B0.0501 (9)0.0367 (10)0.0449 (9)0.0058 (9)0.0050 (7)0.0031 (9)
C15B0.0417 (8)0.0467 (11)0.0299 (7)0.0012 (9)0.0038 (6)0.0006 (8)
C16B0.0541 (10)0.0497 (12)0.0341 (8)0.0093 (10)0.0033 (7)0.0000 (9)
C17B0.0593 (11)0.0640 (16)0.0513 (11)0.0183 (12)0.0012 (9)0.0080 (12)
C18B0.0501 (10)0.0829 (19)0.0513 (11)0.0128 (12)0.0024 (9)0.0138 (13)
C19B0.0698 (13)0.0454 (12)0.0528 (11)0.0068 (11)0.0136 (10)0.0087 (10)
C20B0.0308 (7)0.0492 (11)0.0570 (10)0.0023 (9)0.0082 (7)0.0020 (10)
Geometric parameters (Å, º) top
O1A—C15A1.439 (2)O1B—C15B1.437 (2)
O1A—H1OA0.79 (3)O1B—H1OC0.76 (2)
O2A—C16A1.417 (3)O2B—C16B1.412 (3)
O2A—H1OB0.84 (3)O2B—H1OD0.77 (3)
C1A—C2A1.524 (3)C1B—C2B1.525 (3)
C1A—C10A1.538 (2)C1B—C10B1.541 (3)
C1A—H1AA0.9700C1B—H1BA0.9700
C1A—H1AB0.9700C1B—H1BB0.9700
C2A—C3A1.516 (3)C2B—C3B1.516 (3)
C2A—H2AA0.9700C2B—H2BA0.9700
C2A—H2AB0.9700C2B—H2BB0.9700
C3A—C4A1.532 (3)C3B—C4B1.533 (3)
C3A—H3AA0.9700C3B—H3BA0.9700
C3A—H3AB0.9700C3B—H3BB0.9700
C4A—C18A1.537 (3)C4B—C19B1.530 (3)
C4A—C19A1.541 (3)C4B—C18B1.538 (3)
C4A—C5A1.564 (3)C4B—C5B1.561 (2)
C5A—C6A1.528 (3)C5B—C6B1.528 (3)
C5A—C10A1.556 (2)C5B—C10B1.561 (2)
C5A—H5AA0.9800C5B—H5BA0.9800
C6A—C7A1.528 (3)C6B—C7B1.530 (3)
C6A—H6AA0.9700C6B—H6BA0.9700
C6A—H6AB0.9700C6B—H6BB0.9700
C7A—C8A1.505 (3)C7B—C8B1.503 (3)
C7A—H7AA0.9700C7B—H7BA0.9700
C7A—H7AB0.9700C7B—H7BB0.9700
C8A—C11A1.326 (3)C8B—C11B1.328 (2)
C8A—C9A1.516 (2)C8B—C9B1.515 (3)
C9A—C14A1.531 (3)C9B—C14B1.547 (3)
C9A—C10A1.564 (2)C9B—C10B1.570 (2)
C9A—H9AA0.9800C9B—H9BA0.9800
C10A—C20A1.543 (2)C10B—C20B1.533 (2)
C11A—C12A1.514 (3)C11B—C12B1.510 (3)
C11A—H11A0.9300C11B—H11B0.9300
C12A—C17A1.533 (3)C12B—C17B1.536 (3)
C12A—C15A1.542 (3)C12B—C13B1.536 (2)
C12A—C13A1.545 (3)C12B—C15B1.549 (3)
C13A—C14A1.520 (3)C13B—C14B1.532 (3)
C13A—H13A0.9700C13B—H13C0.9700
C13A—H13B0.9700C13B—H13D0.9700
C14A—H14A0.9700C14B—H14C0.9700
C14A—H14B0.9700C14B—H14D0.9700
C15A—C16A1.511 (3)C15B—C16B1.514 (3)
C15A—H15A0.9800C15B—H15B0.9800
C16A—H16A0.9700C16B—H16C0.9700
C16A—H16B0.9700C16B—H16D0.9700
C17A—H17A0.9600C17B—H17D0.9600
C17A—H17B0.9600C17B—H17E0.9600
C17A—H17C0.9600C17B—H17F0.9600
C18A—H18A0.9600C18B—H18D0.9600
C18A—H18B0.9600C18B—H18E0.9600
C18A—H18C0.9600C18B—H18F0.9600
C19A—H19A0.9600C19B—H19D0.9600
C19A—H19B0.9600C19B—H19E0.9600
C19A—H19C0.9600C19B—H19F0.9600
C20A—H20A0.9600C20B—H20D0.9600
C20A—H20B0.9600C20B—H20E0.9600
C20A—H20C0.9600C20B—H20F0.9600
C15A—O1A—H1OA109 (2)C15B—O1B—H1OC110.8 (19)
C16A—O2A—H1OB108 (3)C16B—O2B—H1OD108 (2)
C2A—C1A—C10A113.59 (16)C2B—C1B—C10B113.41 (17)
C2A—C1A—H1AA108.8C2B—C1B—H1BA108.9
C10A—C1A—H1AA108.8C10B—C1B—H1BA108.9
C2A—C1A—H1AB108.8C2B—C1B—H1BB108.9
C10A—C1A—H1AB108.8C10B—C1B—H1BB108.9
H1AA—C1A—H1AB107.7H1BA—C1B—H1BB107.7
C3A—C2A—C1A110.60 (19)C3B—C2B—C1B110.31 (17)
C3A—C2A—H2AA109.5C3B—C2B—H2BA109.6
C1A—C2A—H2AA109.5C1B—C2B—H2BA109.6
C3A—C2A—H2AB109.5C3B—C2B—H2BB109.6
C1A—C2A—H2AB109.5C1B—C2B—H2BB109.6
H2AA—C2A—H2AB108.1H2BA—C2B—H2BB108.1
C2A—C3A—C4A113.19 (17)C2B—C3B—C4B114.15 (17)
C2A—C3A—H3AA108.9C2B—C3B—H3BA108.7
C4A—C3A—H3AA108.9C4B—C3B—H3BA108.7
C2A—C3A—H3AB108.9C2B—C3B—H3BB108.7
C4A—C3A—H3AB108.9C4B—C3B—H3BB108.7
H3AA—C3A—H3AB107.8H3BA—C3B—H3BB107.6
C3A—C4A—C18A107.15 (17)C19B—C4B—C3B109.71 (16)
C3A—C4A—C19A110.44 (18)C19B—C4B—C18B107.55 (19)
C18A—C4A—C19A107.15 (19)C3B—C4B—C18B107.29 (18)
C3A—C4A—C5A108.64 (15)C19B—C4B—C5B114.69 (16)
C18A—C4A—C5A108.61 (17)C3B—C4B—C5B108.75 (17)
C19A—C4A—C5A114.58 (16)C18B—C4B—C5B108.59 (14)
C6A—C5A—C10A110.52 (14)C6B—C5B—C4B113.92 (16)
C6A—C5A—C4A114.37 (15)C6B—C5B—C10B110.64 (13)
C10A—C5A—C4A116.62 (16)C4B—C5B—C10B117.31 (13)
C6A—C5A—H5AA104.6C6B—C5B—H5BA104.5
C10A—C5A—H5AA104.6C4B—C5B—H5BA104.5
C4A—C5A—H5AA104.6C10B—C5B—H5BA104.5
C7A—C6A—C5A110.60 (15)C5B—C6B—C7B110.01 (18)
C7A—C6A—H6AA109.5C5B—C6B—H6BA109.7
C5A—C6A—H6AA109.5C7B—C6B—H6BA109.7
C7A—C6A—H6AB109.5C5B—C6B—H6BB109.7
C5A—C6A—H6AB109.5C7B—C6B—H6BB109.7
H6AA—C6A—H6AB108.1H6BA—C6B—H6BB108.2
C8A—C7A—C6A113.24 (17)C8B—C7B—C6B111.98 (14)
C8A—C7A—H7AA108.9C8B—C7B—H7BA109.2
C6A—C7A—H7AA108.9C6B—C7B—H7BA109.2
C8A—C7A—H7AB108.9C8B—C7B—H7BB109.2
C6A—C7A—H7AB108.9C6B—C7B—H7BB109.2
H7AA—C7A—H7AB107.7H7BA—C7B—H7BB107.9
C11A—C8A—C7A122.23 (18)C11B—C8B—C7B121.33 (18)
C11A—C8A—C9A123.47 (18)C11B—C8B—C9B123.32 (17)
C7A—C8A—C9A114.20 (15)C7B—C8B—C9B115.28 (15)
C8A—C9A—C14A112.30 (14)C8B—C9B—C14B112.43 (14)
C8A—C9A—C10A111.82 (13)C8B—C9B—C10B112.11 (15)
C14A—C9A—C10A113.74 (16)C14B—C9B—C10B115.59 (13)
C8A—C9A—H9AA106.1C8B—C9B—H9BA105.2
C14A—C9A—H9AA106.1C14B—C9B—H9BA105.2
C10A—C9A—H9AA106.1C10B—C9B—H9BA105.2
C1A—C10A—C20A110.07 (16)C20B—C10B—C1B109.83 (14)
C1A—C10A—C5A109.12 (14)C20B—C10B—C5B114.16 (15)
C20A—C10A—C5A112.87 (14)C1B—C10B—C5B107.78 (14)
C1A—C10A—C9A108.45 (13)C20B—C10B—C9B109.23 (13)
C20A—C10A—C9A109.19 (14)C1B—C10B—C9B108.46 (15)
C5A—C10A—C9A107.01 (14)C5B—C10B—C9B107.21 (12)
C8A—C11A—C12A125.74 (18)C8B—C11B—C12B125.76 (18)
C8A—C11A—H11A117.1C8B—C11B—H11B117.1
C12A—C11A—H11A117.1C12B—C11B—H11B117.1
C11A—C12A—C17A108.28 (19)C11B—C12B—C17B109.18 (15)
C11A—C12A—C15A110.18 (14)C11B—C12B—C13B108.25 (14)
C17A—C12A—C15A111.15 (17)C17B—C12B—C13B111.03 (19)
C11A—C12A—C13A107.27 (15)C11B—C12B—C15B108.32 (17)
C17A—C12A—C13A109.46 (16)C17B—C12B—C15B107.96 (14)
C15A—C12A—C13A110.40 (17)C13B—C12B—C15B112.04 (14)
C14A—C13A—C12A112.70 (14)C14B—C13B—C12B111.87 (14)
C14A—C13A—H13A109.1C14B—C13B—H13C109.2
C12A—C13A—H13A109.1C12B—C13B—H13C109.2
C14A—C13A—H13B109.1C14B—C13B—H13D109.2
C12A—C13A—H13B109.1C12B—C13B—H13D109.2
H13A—C13A—H13B107.8H13C—C13B—H13D107.9
C13A—C14A—C9A112.39 (18)C13B—C14B—C9B114.45 (17)
C13A—C14A—H14A109.1C13B—C14B—H14C108.6
C9A—C14A—H14A109.1C9B—C14B—H14C108.6
C13A—C14A—H14B109.1C13B—C14B—H14D108.6
C9A—C14A—H14B109.1C9B—C14B—H14D108.6
H14A—C14A—H14B107.9H14C—C14B—H14D107.6
O1A—C15A—C16A109.64 (16)O1B—C15B—C16B107.45 (14)
O1A—C15A—C12A108.71 (17)O1B—C15B—C12B111.38 (17)
C16A—C15A—C12A114.79 (16)C16B—C15B—C12B115.05 (13)
O1A—C15A—H15A107.8O1B—C15B—H15B107.6
C16A—C15A—H15A107.8C16B—C15B—H15B107.6
C12A—C15A—H15A107.8C12B—C15B—H15B107.6
O2A—C16A—C15A113.41 (19)O2B—C16B—C15B108.37 (14)
O2A—C16A—H16A108.9O2B—C16B—H16C110.0
C15A—C16A—H16A108.9C15B—C16B—H16C110.0
O2A—C16A—H16B108.9O2B—C16B—H16D110.0
C15A—C16A—H16B108.9C15B—C16B—H16D110.0
H16A—C16A—H16B107.7H16C—C16B—H16D108.4
C12A—C17A—H17A109.5C12B—C17B—H17D109.5
C12A—C17A—H17B109.5C12B—C17B—H17E109.5
H17A—C17A—H17B109.5H17D—C17B—H17E109.5
C12A—C17A—H17C109.5C12B—C17B—H17F109.5
H17A—C17A—H17C109.5H17D—C17B—H17F109.5
H17B—C17A—H17C109.5H17E—C17B—H17F109.5
C4A—C18A—H18A109.5C4B—C18B—H18D109.5
C4A—C18A—H18B109.5C4B—C18B—H18E109.5
H18A—C18A—H18B109.5H18D—C18B—H18E109.5
C4A—C18A—H18C109.5C4B—C18B—H18F109.5
H18A—C18A—H18C109.5H18D—C18B—H18F109.5
H18B—C18A—H18C109.5H18E—C18B—H18F109.5
C4A—C19A—H19A109.5C4B—C19B—H19D109.5
C4A—C19A—H19B109.5C4B—C19B—H19E109.5
H19A—C19A—H19B109.5H19D—C19B—H19E109.5
C4A—C19A—H19C109.5C4B—C19B—H19F109.5
H19A—C19A—H19C109.5H19D—C19B—H19F109.5
H19B—C19A—H19C109.5H19E—C19B—H19F109.5
C10A—C20A—H20A109.5C10B—C20B—H20D109.5
C10A—C20A—H20B109.5C10B—C20B—H20E109.5
H20A—C20A—H20B109.5H20D—C20B—H20E109.5
C10A—C20A—H20C109.5C10B—C20B—H20F109.5
H20A—C20A—H20C109.5H20D—C20B—H20F109.5
H20B—C20A—H20C109.5H20E—C20B—H20F109.5
C10A—C1A—C2A—C3A57.5 (2)C10B—C1B—C2B—C3B58.9 (2)
C1A—C2A—C3A—C4A58.9 (2)C1B—C2B—C3B—C4B57.5 (3)
C2A—C3A—C4A—C18A170.75 (19)C2B—C3B—C4B—C19B75.1 (2)
C2A—C3A—C4A—C19A72.9 (2)C2B—C3B—C4B—C18B168.35 (18)
C2A—C3A—C4A—C5A53.6 (2)C2B—C3B—C4B—C5B51.1 (2)
C3A—C4A—C5A—C6A179.29 (16)C19B—C4B—C5B—C6B56.8 (2)
C18A—C4A—C5A—C6A63.1 (2)C3B—C4B—C5B—C6B179.95 (15)
C19A—C4A—C5A—C6A56.7 (2)C18B—C4B—C5B—C6B63.5 (2)
C3A—C4A—C5A—C10A49.6 (2)C19B—C4B—C5B—C10B74.7 (2)
C18A—C4A—C5A—C10A165.82 (16)C3B—C4B—C5B—C10B48.5 (2)
C19A—C4A—C5A—C10A74.4 (2)C18B—C4B—C5B—C10B164.97 (18)
C10A—C5A—C6A—C7A59.7 (2)C4B—C5B—C6B—C7B163.57 (14)
C4A—C5A—C6A—C7A166.33 (16)C10B—C5B—C6B—C7B61.74 (19)
C5A—C6A—C7A—C8A51.7 (2)C5B—C6B—C7B—C8B54.2 (2)
C6A—C7A—C8A—C11A135.30 (19)C6B—C7B—C8B—C11B133.6 (2)
C6A—C7A—C8A—C9A48.2 (2)C6B—C7B—C8B—C9B49.5 (2)
C11A—C8A—C9A—C14A2.8 (2)C11B—C8B—C9B—C14B0.7 (3)
C7A—C8A—C9A—C14A179.18 (15)C7B—C8B—C9B—C14B177.58 (16)
C11A—C8A—C9A—C10A132.04 (19)C11B—C8B—C9B—C10B132.89 (18)
C7A—C8A—C9A—C10A51.6 (2)C7B—C8B—C9B—C10B50.2 (2)
C2A—C1A—C10A—C20A73.3 (2)C2B—C1B—C10B—C20B71.4 (2)
C2A—C1A—C10A—C5A51.1 (2)C2B—C1B—C10B—C5B53.5 (2)
C2A—C1A—C10A—C9A167.33 (18)C2B—C1B—C10B—C9B169.27 (16)
C6A—C5A—C10A—C1A178.74 (15)C6B—C5B—C10B—C20B60.38 (19)
C4A—C5A—C10A—C1A48.38 (19)C4B—C5B—C10B—C20B72.6 (2)
C6A—C5A—C10A—C20A58.6 (2)C6B—C5B—C10B—C1B177.32 (15)
C4A—C5A—C10A—C20A74.33 (19)C4B—C5B—C10B—C1B49.7 (2)
C6A—C5A—C10A—C9A61.59 (17)C6B—C5B—C10B—C9B60.74 (18)
C4A—C5A—C10A—C9A165.53 (13)C4B—C5B—C10B—C9B166.26 (16)
C8A—C9A—C10A—C1A174.49 (15)C8B—C9B—C10B—C20B70.25 (18)
C14A—C9A—C10A—C1A57.00 (18)C14B—C9B—C10B—C20B60.4 (2)
C8A—C9A—C10A—C20A65.57 (19)C8B—C9B—C10B—C1B170.06 (14)
C14A—C9A—C10A—C20A62.94 (18)C14B—C9B—C10B—C1B59.31 (19)
C8A—C9A—C10A—C5A56.90 (17)C8B—C9B—C10B—C5B53.94 (17)
C14A—C9A—C10A—C5A174.59 (13)C14B—C9B—C10B—C5B175.43 (15)
C7A—C8A—C11A—C12A171.68 (17)C7B—C8B—C11B—C12B179.05 (18)
C9A—C8A—C11A—C12A4.4 (3)C9B—C8B—C11B—C12B2.3 (3)
C8A—C11A—C12A—C17A137.0 (2)C8B—C11B—C12B—C17B97.3 (2)
C8A—C11A—C12A—C15A101.3 (2)C8B—C11B—C12B—C13B23.7 (3)
C8A—C11A—C12A—C13A19.0 (3)C8B—C11B—C12B—C15B145.38 (19)
C11A—C12A—C13A—C14A49.8 (2)C11B—C12B—C13B—C14B50.4 (2)
C17A—C12A—C13A—C14A167.1 (2)C17B—C12B—C13B—C14B69.4 (2)
C15A—C12A—C13A—C14A70.3 (2)C15B—C12B—C13B—C14B169.82 (17)
C12A—C13A—C14A—C9A59.8 (2)C12B—C13B—C14B—C9B55.3 (2)
C8A—C9A—C14A—C13A33.8 (2)C8B—C9B—C14B—C13B27.9 (2)
C10A—C9A—C14A—C13A162.06 (14)C10B—C9B—C14B—C13B102.53 (18)
C11A—C12A—C15A—O1A47.6 (2)C11B—C12B—C15B—O1B176.96 (13)
C17A—C12A—C15A—O1A72.4 (2)C17B—C12B—C15B—O1B58.86 (19)
C13A—C12A—C15A—O1A165.91 (15)C13B—C12B—C15B—O1B63.70 (19)
C11A—C12A—C15A—C16A170.79 (18)C11B—C12B—C15B—C16B60.46 (19)
C17A—C12A—C15A—C16A50.8 (3)C17B—C12B—C15B—C16B178.56 (18)
C13A—C12A—C15A—C16A70.9 (2)C13B—C12B—C15B—C16B58.9 (2)
O1A—C15A—C16A—O2A75.0 (3)O1B—C15B—C16B—O2B73.8 (2)
C12A—C15A—C16A—O2A162.28 (18)C12B—C15B—C16B—O2B161.55 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1A—H1OA···O1Bi0.78 (3)2.06 (3)2.839 (2)174 (3)
O2A—H1OB···O1Bi0.84 (4)2.14 (4)2.931 (2)158 (3)
O1B—H1OC···O2Bii0.76 (2)1.96 (2)2.719 (2)178 (3)
O2B—H1OD···O1Aiii0.77 (3)2.13 (3)2.795 (3)145 (3)
Symmetry codes: (i) x+1, y, z; (ii) x, y+1/2, z; (iii) x1, y1, z.

Experimental details

Crystal data
Chemical formulaC20H34O2
Mr306.47
Crystal system, space groupMonoclinic, P21
Temperature (K)273
a, b, c (Å)11.5129 (2), 7.0934 (1), 22.3946 (4)
β (°) 96.750 (1)
V3)1816.19 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.07
Crystal size (mm)0.56 × 0.34 × 0.25
Data collection
DiffractometerBruker SMART APEX2 CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.962, 0.983
No. of measured, independent and
observed [I > 2σ(I)] reflections
28246, 5205, 4504
Rint0.031
(sin θ/λ)max1)0.682
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.041, 0.106, 1.03
No. of reflections5205
No. of parameters421
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.17, 0.16

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1A—H1OA···O1Bi0.78 (3)2.06 (3)2.839 (2)174 (3)
O2A—H1OB···O1Bi0.84 (4)2.14 (4)2.931 (2)158 (3)
O1B—H1OC···O2Bii0.76 (2)1.96 (2)2.719 (2)178 (3)
O2B—H1OD···O1Aiii0.77 (3)2.13 (3)2.795 (3)145 (3)
Symmetry codes: (i) x+1, y, z; (ii) x, y+1/2, z; (iii) x1, y1, z.
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009.

§Additional correspondence author, e-mail: suchada.c@psu.ac.th. Thomson Reuters ResearcherID: A-5085-2009.

Acknowledgements

The authors thank the Prince of Songkla University for financial support through the Crystal Materials Research Unit. The authors also thank Universiti Sains Malaysia for the Research University Grant No. 1001/PFIZIK/811160.

References

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Volume 68| Part 2| February 2012| Pages o520-o521
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