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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

3α,4α-Ep­­oxy-5α-androstan-17β-yl acetate

aCEMDRX, Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, P-3004-516 Coimbra, Portugal, and bCentro de Estudos Farmacêuticos, Laboratório de Química Farmacêutica, Faculdade de Farmácia, Universidade de Coimbra, P-3000-295 Coimbra, Portugal
*Correspondence e-mail: jap@pollux.fis.uc.pt

(Received 11 December 2008; accepted 11 March 2009; online 25 March 2009)

The title compound, C21H32O3, results from modifications of the A and D rings of the aromatase substrate androstenedione. Ring A adopts a conformation between 10β-sofa and 1α,10β half-chair. Rings B and C are in slightly flattened chair conformations. Ring D approaches a 13β-envelope conformation, probably due to the acet­oxy substituent, and shows a very short Csp3—Csp3 bond next to the epoxide ring, which is characteristic of 3–4 epoxides. .

Related literature

For the antitumor and anti-aromatase activity of aromatase substrate derivatives, see: Cepa et al. (2005[Cepa, M. M. D. S., Tavares da Silva, E. J., Correia-da-Silva, G., Roleira, F. M. & Teixeira, N. A. A. (2005). J. Med. Chem. 48, 6379-6385.]). For related structures, see: Paixão et al. (1997[Paixão, J. A., Ramos Silva, M., de Almeida, M. J., Tavares da Silva, E. J., Sá e Melo, M. L. & Campos Neves, A. S. (1997). Acta Cryst. C53, 347-349.]); Andrade et al. (1997[Andrade, L. C. R., Paixão, J. A., de Almeida, M. J., Tavares da Silva, E. J., Sá e Melo, M. L. & Campos Neves, A. S. (1997). Acta Cryst. C53, 938-940.]). For bond-length data,, 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 asymmetry, pseudo-rotation and puckering parameters, see: Duax & Norton (1975[Duax, W. L. & Norton, D. A. (1975). In Atlas of Steroids Structure, Vol. 1. New York: Plenum.]); Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]); Altona et al. (1968[Altona, C., Geise, H. J. & Romers, C. (1968). Tetrahedron, 24, 13-32.]).

[Scheme 1]

Experimental

Crystal data
  • C21H32O3

  • Mr = 332.47

  • Orthorhombic, P 21 21 21

  • a = 6.2760 (2) Å

  • b = 11.7272 (19) Å

  • c = 25.0888 (9) Å

  • V = 1846.5 (3) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 0.61 mm−1

  • T = 293 K

  • 0.36 × 0.20 × 0.12 mm

Data collection
  • Enraf–Nonius MACH-3 diffractometer

  • Absorption correction: none

  • 2661 measured reflections

  • 2146 independent reflections

  • 1715 reflections with I > 2σ(I)

  • Rint = 0.050

  • 3 standard reflections every 300 reflections intensity decay: 1.3%

Refinement
  • R[F2 > 2σ(F2)] = 0.044

  • wR(F2) = 0.135

  • S = 1.03

  • 2146 reflections

  • 221 parameters

  • H-atom parameters constrained

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.18 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), with 0 Friedel pairs

  • Flack parameter: −0.1 (5)

Data collection: CAD-4 Software (Enraf–Nonius, 1989[Enraf-Nonius (1989). CAD-4 Software. Enraf-Nonius, Delft, The Netherlands.]); cell refinement: CAD-4 Software; data reduction: HELENA (Spek, 1997[Spek, A. L. (1997). HELENA. University of Utrecht, The Netherlands.]) and PLATON Spek (2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); 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: ORTEPII (Johnson, 1976[Johnson, C. K. (1976). ORTEPII. Report ORNL-5138. Oak Ridge National Laboratory, Tennessee, USA.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Recently, a new series of steroids, which result from modifications in the A– and D-rings of the aromatase substrate, androstenedione, were designed, synthesized and evaluated for their anti-tumour and anti-aromatase activity (Cepa et al., 2005). The researches have considered three main structural features for the drug-enzyme interactions, namely, the planarity of the A-ring, the 5α-stereochemistry and the integrity of the cyclopentanone D-ring. In the present work, we are focused on the effect of some refined modifications in the original C–17 carbonyl group in the D-ring of steroids in enzyme inhibition. This study is a contribution to the understanding of the role of the D-ring substitution pattern and its structure in the inhibition of aromatase. Under this project, the title compound (I) was synthesized. In order to establish the conformation of (I), the X-ray structure was determined (Fig. 1). Atomic distances are within expected values (Allen et al., 1987) except for the C2–C3 bond which is much shorter [1.482 (5) Å] than the determined average value for Csp3–Csp3 bond lengths in the molecule [1.532 (16) Å]. This is probably characteristic of 3–4 epoxides since similar values [1.494 (4) and 1.484 (5) Å] were obtained for two related structures (Paixão et al., 1997 and Andrade et al., 1997). The ring A [C1C10] is severely distorted assuming a conformation intermediate between10β-sofa and 1α,10β-half chair [asymmetry parametres (Duax & Norton, 1975): ΔCs(3)=11.4 (3), ΔC2(3,4)=14.8 (4) and ΔC2(1,2)=53.5 (4)°]. Rings B [C5C10] and C [C8-C14] have slightly flattened chair conformations evidenced by the average values of their torsion angles [56 (2)° for both]. The five member ring D [C13C17] assumes a conformation intermediate between 13β-envelope and 13β,14α-half chair, probably due to the acetoxy substituent [puckering parametres (Cremer & Pople, 1975) q2=0.477 (3)Å and ϕ2=188.6 (4)°; pseudo-rotation (Altona et al., 1968) and asymmetry parameters (Duax & Norton, 1975): Δ=18.8 (4), ϕm=48.5 (2), ΔCs(13)=8.9 (3), ΔC2(13,14)=12.7 (3) and ΔCs(14)=27.2 (3)°). The distance between terminal O atoms is 11.204 (3)°. A pseudo-torsion angle C19–C10···C13–C18 of 1.6 (2) ° evidences that the molecule is not twisted. The dihedral angle between the least-squares plane of the four non-H atoms of the acetate group and that of ring D is 65.04 (17)°. The crystal packing is determined by van der Waals interactions.

Related literature top

For the anti-tumor and anti-aromatase activity of aromatase substrate derivatives, see: Cepa et al. (2005). For related structures, see: Paixão et al. (1997); Andrade et al. (1997). For bond-length data,, see: Allen et al. (1987). For aymmetry, pseudo-rotation and puckering parameters, see: Duax & Norton (1975); Cremer & Pople (1975); Altona et al. (1968).

Experimental top

To a solution of 5α-androst-3-en-17β-yl acetate (308 mg, 0.97 mmol) in methylene chloride (5.0 ml), a solution of performic acid (0.15 ml of HCOOH 98–100% and 0.4 ml of H2O2 35%) was added and the reaction stirred overnight until complete transformation of starting material. Methylene chloride (150 ml) was added and the organic layer was washed with 10% NaHCO3 (2x100 ml) and water (4x100 ml) and then dried over anhydrous MgSO4. After filtration and solvent evaporation to dryness, the almost pure title compound was obtained as a white solid (296 mg, 92%). Column chromatography (silica gel 60 with 95: 5 to 95: 10 mixtures of petroleum ether 40–60 °C and ethyl acetate) or crystallization from ethyl acetate n–hexane, yielded analytical samples: Mp 461–463 K; IR νmax(KBr) cm-1: 1732 (C?O); 1H NMR (300 MHz, CDCl3) δ: 0.77 (3H, s, 18-H3)*, 0.78 (3H, s, 19-H3)*, 2.03 (3H, s, CH3COO), 2.69 (1H, d, J4β,5α=3.9, 4β-H), 3.16 (1H, dd, J3β,2α=3.0, J3β,2β=3.0, 3β-H), 4.58 (1H, dd, J17α,16α=9.0, J17α,16β=7.8, 17α-H); 13C NMR (75.6 MHz, DMSO-d6) δ: 12.1 (C-19), 13.4 (C-18), 20.7, 21.2, 21.3, 23.4, 26.6, 27.5, 30.4, 31.4, 34.1, 35.1, 36.8, 42.6, 46.7, 50.5 52.1**, 52.5 (C-4)**, 55.8 (C-3), 82.7 (C-17); 171.2 (C?O); EIMS m/z 332 (M+, 87%). *,** Signals may be interchangeable.

Refinement top

All hydrogen atoms were refined as riding on their parent atoms using SHELXL97. The absolute configuration was not determined from the X-ray data but was known from the synthesis route. Friedel pairs were merged before refinement.

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software (Enraf–Nonius, 1989); data reduction: HELENA (Spek, 1997) and PLATON Spek (2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. ORTEPII (Johnson, 1976) of (I). Displacement ellipsoids are drawn at the 50% probability level.
3α,4α-Epoxy-5α-androstan-17β-yl acetate top
Crystal data top
C21H32O3Dx = 1.196 Mg m3
Mr = 332.47Cu Kα radiation, λ = 1.54180 Å
Orthorhombic, P212121Cell parameters from 25 reflections
a = 6.2760 (2) Åθ = 13.4–28.2°
b = 11.7272 (19) ŵ = 0.61 mm1
c = 25.0888 (9) ÅT = 293 K
V = 1846.5 (3) Å3Truncated pyramid, colourless
Z = 40.36 × 0.20 × 0.12 mm
F(000) = 728
Data collection top
Enraf–Nonius MACH-3
diffractometer
Rint = 0.050
Radiation source: fine-focus sealed tubeθmax = 73.8°, θmin = 3.5°
Graphite monochromatorh = 67
Profile data from ω–2θ scansk = 014
2661 measured reflectionsl = 031
2146 independent reflections3 standard reflections every 300 reflections
1715 reflections with I > 2σ(I) intensity decay: 1.3%
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.044 w = 1/[σ2(Fo2) + (0.0886P)2 + 0.2976P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.135(Δ/σ)max = 0.004
S = 1.03Δρmax = 0.23 e Å3
2146 reflectionsΔρmin = 0.18 e Å3
221 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.0030 (6)
Primary atom site location: structure-invariant direct methodsAbsolute structure: Flack (1983), 0 Friedel pairs
Secondary atom site location: difference Fourier mapAbsolute structure parameter: 0.1 (5)
Crystal data top
C21H32O3V = 1846.5 (3) Å3
Mr = 332.47Z = 4
Orthorhombic, P212121Cu Kα radiation
a = 6.2760 (2) ŵ = 0.61 mm1
b = 11.7272 (19) ÅT = 293 K
c = 25.0888 (9) Å0.36 × 0.20 × 0.12 mm
Data collection top
Enraf–Nonius MACH-3
diffractometer
Rint = 0.050
2661 measured reflections3 standard reflections every 300 reflections
2146 independent reflections intensity decay: 1.3%
1715 reflections with I > 2σ(I)
Refinement top
R[F2 > 2σ(F2)] = 0.044H-atom parameters constrained
wR(F2) = 0.135Δρmax = 0.23 e Å3
S = 1.03Δρmin = 0.18 e Å3
2146 reflectionsAbsolute structure: Flack (1983), 0 Friedel pairs
221 parametersAbsolute structure parameter: 0.1 (5)
0 restraints
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
O30.6940 (5)0.54519 (19)0.50056 (8)0.0627 (7)
O17A1.1217 (4)0.38347 (16)0.12529 (7)0.0536 (6)
O17B1.2588 (5)0.52535 (19)0.07703 (9)0.0669 (7)
C10.9480 (5)0.3851 (3)0.42667 (10)0.0481 (7)
H1A1.04060.32370.41500.058*
H1B1.03400.45350.42980.058*
C20.8561 (6)0.3552 (3)0.48152 (11)0.0565 (8)
H2A0.81670.27520.48160.068*
H2B0.96670.36550.50810.068*
C30.6677 (6)0.4235 (3)0.49734 (11)0.0529 (8)
H30.57530.38920.52440.063*
C40.5617 (5)0.4987 (3)0.45865 (10)0.0480 (7)
H40.40750.50830.46300.058*
C50.6477 (5)0.5113 (2)0.40261 (9)0.0381 (6)
H50.75000.57440.40380.046*
C60.4757 (5)0.5465 (2)0.36317 (10)0.0436 (6)
H6A0.40180.61340.37630.052*
H6B0.37260.48540.35940.052*
C70.5761 (5)0.5727 (2)0.30914 (10)0.0431 (6)
H7A0.66660.63930.31240.052*
H7B0.46430.59040.28370.052*
C80.7080 (4)0.4730 (2)0.28806 (9)0.0338 (5)
H80.61140.40900.28120.041*
C90.8761 (4)0.4339 (2)0.32915 (9)0.0340 (5)
H90.97030.49930.33520.041*
C100.7745 (4)0.4048 (2)0.38411 (9)0.0352 (5)
C111.0165 (4)0.3385 (2)0.30642 (10)0.0407 (6)
H11A0.93060.27040.30180.049*
H11B1.12820.32090.33180.049*
C121.1185 (5)0.3702 (3)0.25284 (10)0.0429 (6)
H12A1.21720.43290.25810.051*
H12B1.19830.30560.23930.051*
C130.9502 (4)0.4047 (2)0.21221 (9)0.0355 (6)
C140.8196 (4)0.5035 (2)0.23599 (9)0.0359 (6)
H140.92180.56390.24460.043*
C150.6882 (5)0.5471 (3)0.18884 (10)0.0501 (7)
H15A0.65080.62670.19350.060*
H15B0.55870.50280.18460.060*
C160.8385 (5)0.5311 (3)0.14039 (10)0.0496 (7)
H16A0.76860.48790.11250.060*
H16B0.88190.60440.12610.060*
C171.0306 (5)0.4658 (2)0.16230 (10)0.0427 (6)
H171.14110.52060.17260.051*
C17A1.2337 (5)0.4256 (3)0.08422 (11)0.0496 (7)
C17B1.3214 (8)0.3334 (3)0.05006 (14)0.0751 (12)
H17A1.41470.36590.02380.090*
H17B1.20660.29430.03260.090*
H17C1.39960.28050.07170.090*
C180.8135 (6)0.3021 (2)0.19638 (12)0.0507 (7)
H18A0.90210.24500.18020.061*
H18B0.70620.32580.17150.061*
H18C0.74640.27100.22750.061*
C190.6299 (5)0.2992 (2)0.38040 (11)0.0433 (6)
H19A0.71630.23180.37870.052*
H19B0.54350.30430.34890.052*
H19C0.53980.29570.41130.052*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O30.0852 (18)0.0598 (13)0.0431 (10)0.0031 (14)0.0105 (12)0.0122 (10)
O17A0.0745 (15)0.0438 (10)0.0426 (10)0.0005 (11)0.0153 (11)0.0037 (9)
O17B0.0881 (18)0.0506 (12)0.0620 (13)0.0109 (14)0.0256 (14)0.0019 (11)
C10.0472 (15)0.0599 (17)0.0371 (13)0.0056 (15)0.0072 (13)0.0053 (13)
C20.066 (2)0.0656 (19)0.0380 (13)0.0059 (18)0.0084 (15)0.0076 (13)
C30.066 (2)0.0574 (17)0.0348 (13)0.0033 (17)0.0006 (14)0.0005 (12)
C40.0508 (16)0.0553 (16)0.0378 (13)0.0003 (15)0.0003 (13)0.0072 (12)
C50.0395 (14)0.0380 (13)0.0368 (12)0.0002 (12)0.0013 (11)0.0000 (10)
C60.0413 (14)0.0473 (14)0.0421 (13)0.0122 (13)0.0042 (12)0.0019 (11)
C70.0446 (15)0.0449 (14)0.0397 (13)0.0113 (13)0.0003 (12)0.0080 (11)
C80.0317 (11)0.0353 (12)0.0343 (11)0.0004 (11)0.0021 (10)0.0025 (9)
C90.0315 (11)0.0355 (12)0.0349 (11)0.0004 (11)0.0032 (10)0.0012 (10)
C100.0368 (13)0.0347 (12)0.0340 (11)0.0015 (12)0.0027 (11)0.0032 (9)
C110.0394 (13)0.0445 (14)0.0381 (12)0.0095 (13)0.0041 (11)0.0034 (11)
C120.0380 (14)0.0496 (15)0.0411 (13)0.0068 (13)0.0014 (12)0.0026 (11)
C130.0383 (13)0.0330 (12)0.0351 (12)0.0018 (11)0.0009 (11)0.0022 (10)
C140.0362 (13)0.0359 (12)0.0357 (12)0.0005 (11)0.0028 (11)0.0024 (10)
C150.0516 (16)0.0585 (17)0.0401 (13)0.0086 (15)0.0038 (14)0.0099 (13)
C160.0633 (19)0.0504 (15)0.0351 (12)0.0043 (16)0.0023 (13)0.0052 (12)
C170.0508 (15)0.0402 (13)0.0372 (12)0.0050 (14)0.0065 (12)0.0037 (11)
C17A0.0558 (18)0.0517 (16)0.0414 (13)0.0010 (15)0.0088 (14)0.0001 (12)
C17B0.110 (3)0.056 (2)0.0590 (19)0.011 (2)0.030 (2)0.0007 (16)
C180.0618 (19)0.0430 (14)0.0474 (15)0.0150 (15)0.0002 (15)0.0022 (12)
C190.0489 (15)0.0384 (13)0.0427 (13)0.0039 (13)0.0024 (13)0.0039 (11)
Geometric parameters (Å, º) top
O3—C31.439 (4)C9—H90.9800
O3—C41.447 (3)C10—C191.537 (4)
O17A—C17A1.342 (3)C11—C121.535 (4)
O17A—C171.457 (3)C11—H11A0.9700
O17B—C17A1.194 (4)C11—H11B0.9700
C1—C21.533 (4)C12—C131.523 (4)
C1—C101.543 (4)C12—H12A0.9700
C1—H1A0.9700C12—H12B0.9700
C1—H1B0.9700C13—C171.528 (3)
C2—C31.482 (5)C13—C181.531 (4)
C2—H2A0.9700C13—C141.539 (4)
C2—H2B0.9700C14—C151.530 (3)
C3—C41.471 (4)C14—H140.9800
C3—H30.9800C15—C161.550 (4)
C4—C51.513 (4)C15—H15A0.9700
C4—H40.9800C15—H15B0.9700
C5—C61.521 (4)C16—C171.530 (4)
C5—C101.553 (4)C16—H16A0.9700
C5—H50.9800C16—H16B0.9700
C6—C71.526 (4)C17—H170.9800
C6—H6A0.9700C17A—C17B1.485 (4)
C6—H6B0.9700C17B—H17A0.9600
C7—C81.526 (4)C17B—H17B0.9600
C7—H7A0.9700C17B—H17C0.9600
C7—H7B0.9700C18—H18A0.9600
C8—C141.525 (3)C18—H18B0.9600
C8—C91.545 (3)C18—H18C0.9600
C8—H80.9800C19—H19A0.9600
C9—C111.534 (4)C19—H19B0.9600
C9—C101.557 (3)C19—H19C0.9600
C3—O3—C461.3 (2)C9—C11—H11A109.0
C17A—O17A—C17116.8 (2)C12—C11—H11A109.0
C2—C1—C10112.9 (3)C9—C11—H11B109.0
C2—C1—H1A109.0C12—C11—H11B109.0
C10—C1—H1A109.0H11A—C11—H11B107.8
C2—C1—H1B109.0C13—C12—C11111.2 (2)
C10—C1—H1B109.0C13—C12—H12A109.4
H1A—C1—H1B107.8C11—C12—H12A109.4
C3—C2—C1114.6 (3)C13—C12—H12B109.4
C3—C2—H2A108.6C11—C12—H12B109.4
C1—C2—H2A108.6H12A—C12—H12B108.0
C3—C2—H2B108.6C12—C13—C17116.4 (2)
C1—C2—H2B108.6C12—C13—C18110.7 (2)
H2A—C2—H2B107.6C17—C13—C18110.0 (2)
O3—C3—C459.62 (19)C12—C13—C14108.0 (2)
O3—C3—C2117.4 (3)C17—C13—C1498.1 (2)
C4—C3—C2120.6 (3)C18—C13—C14113.2 (2)
O3—C3—H3115.8C8—C14—C15119.5 (2)
C4—C3—H3115.8C8—C14—C13113.7 (2)
C2—C3—H3115.8C15—C14—C13103.8 (2)
O3—C4—C359.08 (18)C8—C14—H14106.3
O3—C4—C5115.7 (3)C15—C14—H14106.3
C3—C4—C5120.7 (3)C13—C14—H14106.3
O3—C4—H4116.3C14—C15—C16103.8 (2)
C3—C4—H4116.3C14—C15—H15A111.0
C5—C4—H4116.3C16—C15—H15A111.0
C4—C5—C6112.2 (2)C14—C15—H15B111.0
C4—C5—C10112.4 (2)C16—C15—H15B111.0
C6—C5—C10112.8 (2)H15A—C15—H15B109.0
C4—C5—H5106.3C17—C16—C15105.0 (2)
C6—C5—H5106.3C17—C16—H16A110.8
C10—C5—H5106.3C15—C16—H16A110.8
C5—C6—C7109.8 (2)C17—C16—H16B110.8
C5—C6—H6A109.7C15—C16—H16B110.8
C7—C6—H6A109.7H16A—C16—H16B108.8
C5—C6—H6B109.7O17A—C17—C13109.9 (2)
C7—C6—H6B109.7O17A—C17—C16114.3 (2)
H6A—C6—H6B108.2C13—C17—C16105.6 (2)
C6—C7—C8112.2 (2)O17A—C17—H17109.0
C6—C7—H7A109.2C13—C17—H17109.0
C8—C7—H7A109.2C16—C17—H17109.0
C6—C7—H7B109.2O17B—C17A—O17A123.1 (3)
C8—C7—H7B109.2O17B—C17A—C17B125.2 (3)
H7A—C7—H7B107.9O17A—C17A—C17B111.7 (3)
C14—C8—C7111.5 (2)C17A—C17B—H17A109.5
C14—C8—C9109.1 (2)C17A—C17B—H17B109.5
C7—C8—C9111.5 (2)H17A—C17B—H17B109.5
C14—C8—H8108.2C17A—C17B—H17C109.5
C7—C8—H8108.2H17A—C17B—H17C109.5
C9—C8—H8108.2H17B—C17B—H17C109.5
C11—C9—C8111.17 (19)C13—C18—H18A109.5
C11—C9—C10113.9 (2)C13—C18—H18B109.5
C8—C9—C10112.1 (2)H18A—C18—H18B109.5
C11—C9—H9106.4C13—C18—H18C109.5
C8—C9—H9106.4H18A—C18—H18C109.5
C10—C9—H9106.4H18B—C18—H18C109.5
C19—C10—C1109.8 (2)C10—C19—H19A109.5
C19—C10—C5111.3 (2)C10—C19—H19B109.5
C1—C10—C5106.0 (2)H19A—C19—H19B109.5
C19—C10—C9111.4 (2)C10—C19—H19C109.5
C1—C10—C9110.9 (2)H19A—C19—H19C109.5
C5—C10—C9107.36 (19)H19B—C19—H19C109.5
C9—C11—C12112.8 (2)
C10—C1—C2—C342.1 (4)C11—C9—C10—C5177.3 (2)
C4—O3—C3—C2111.1 (3)C8—C9—C10—C555.4 (3)
C1—C2—C3—O359.3 (4)C8—C9—C11—C1253.4 (3)
C1—C2—C3—C49.8 (4)C10—C9—C11—C12178.8 (2)
C3—O3—C4—C5111.8 (3)C9—C11—C12—C1355.7 (3)
C2—C3—C4—O3105.8 (4)C11—C12—C13—C17165.4 (2)
O3—C3—C4—C5103.4 (3)C11—C12—C13—C1868.1 (3)
C2—C3—C4—C52.4 (5)C11—C12—C13—C1456.4 (3)
O3—C4—C5—C6137.4 (3)C7—C8—C14—C1555.3 (3)
C3—C4—C5—C6154.8 (3)C9—C8—C14—C15178.9 (2)
O3—C4—C5—C1094.2 (3)C7—C8—C14—C13178.4 (2)
C3—C4—C5—C1026.4 (4)C9—C8—C14—C1357.9 (3)
C4—C5—C6—C7172.8 (2)C12—C13—C14—C859.6 (3)
C10—C5—C6—C759.0 (3)C17—C13—C14—C8179.2 (2)
C5—C6—C7—C855.4 (3)C18—C13—C14—C863.4 (3)
C6—C7—C8—C14176.0 (2)C12—C13—C14—C15169.0 (2)
C6—C7—C8—C953.8 (3)C17—C13—C14—C1547.8 (2)
C14—C8—C9—C1153.0 (3)C18—C13—C14—C1568.0 (3)
C7—C8—C9—C11176.7 (2)C8—C14—C15—C16162.5 (2)
C14—C8—C9—C10178.26 (19)C13—C14—C15—C1634.7 (3)
C7—C8—C9—C1054.6 (3)C14—C15—C16—C177.2 (3)
C2—C1—C10—C1956.1 (3)C17A—O17A—C17—C13168.1 (2)
C2—C1—C10—C564.3 (3)C17A—O17A—C17—C1673.4 (3)
C2—C1—C10—C9179.5 (2)C12—C13—C17—O17A78.1 (3)
C4—C5—C10—C1964.4 (3)C18—C13—C17—O17A48.7 (3)
C6—C5—C10—C1963.7 (3)C14—C13—C17—O17A167.0 (2)
C4—C5—C10—C154.9 (3)C12—C13—C17—C16158.1 (2)
C6—C5—C10—C1177.0 (2)C18—C13—C17—C1675.1 (3)
C4—C5—C10—C9173.4 (2)C14—C13—C17—C1643.3 (2)
C6—C5—C10—C958.5 (3)C15—C16—C17—O17A144.0 (3)
C11—C9—C10—C1960.6 (3)C15—C16—C17—C1323.0 (3)
C8—C9—C10—C1966.7 (3)C17—O17A—C17A—O17B0.7 (5)
C11—C9—C10—C162.0 (3)C17—O17A—C17A—C17B178.9 (3)
C8—C9—C10—C1170.7 (2)C19—C10—C13—C181.6 (2)

Experimental details

Crystal data
Chemical formulaC21H32O3
Mr332.47
Crystal system, space groupOrthorhombic, P212121
Temperature (K)293
a, b, c (Å)6.2760 (2), 11.7272 (19), 25.0888 (9)
V3)1846.5 (3)
Z4
Radiation typeCu Kα
µ (mm1)0.61
Crystal size (mm)0.36 × 0.20 × 0.12
Data collection
DiffractometerEnraf–Nonius MACH-3
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
2661, 2146, 1715
Rint0.050
(sin θ/λ)max1)0.623
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.044, 0.135, 1.03
No. of reflections2146
No. of parameters221
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.23, 0.18
Absolute structureFlack (1983), 0 Friedel pairs
Absolute structure parameter0.1 (5)

Computer programs: CAD-4 Software (Enraf–Nonius, 1989), HELENA (Spek, 1997) and PLATON Spek (2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPII (Johnson, 1976).

 

Acknowledgements

This work was supported by Fundação para a Ciência e Tecnologia.

References

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