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Acta Crystallogr Sect E Struct Rep Online. 2010 June 1; 66(Pt 6): o1517–o1518.
Published online 2010 May 29. doi:  10.1107/S1600536810019720
PMCID: PMC2979654

Redetermination of 5α-androstane-3,17-dione

Abstract

The structure of the title compound, C19H28O2, has been redermined at 295 (2) K, with much improved precision. The structure and mol­ecular packing of the title compound was first reported by Coiro et al. [Acta Cryst. (1973). B29, 1404–1409] by means of potential-energy calculations. The cell parameters in this study differ considerably in space group C2. It is a derivative of testosterone and consists of a cyclo­penta­none ring (A) fused to to successive cyclo­hexane (B and C) and cyclo­hexa­none (D) rings. The three cyclo­hexa­none rings are in slightly distorted boat configurations and the cyclo­penta­none ring is a distorted half-chair. The crystal packing is stabilized by weak inter­molecular C—H(...)O inter­actions involving O atoms from each of the cyclo­hexa­none and cyclo­penta­none rings and H atoms from each of their respective rings.

Related literature

For biotransformation studies, see: Fiorentino et al. (1991 [triangle]). For the previous report of this structure, see: Coiro et al. (1973 [triangle]); For related structures, see: Anthony et al. (1998 [triangle]); Jasinski et al. (2009 [triangle]); Norton et al. (1962 [triangle]); Ohrt et al. (1965 [triangle]). For bond-length data, see: Allen et al. (1987 [triangle]). For puckering parameters, see: Cremer & Pople (1975 [triangle]).

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Object name is e-66-o1517-scheme1.jpg

Experimental

Crystal data

  • C19H28O2
  • M r = 288.41
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1517-efi1.jpg
  • a = 12.7786 (6) Å
  • b = 6.7850 (4) Å
  • c = 19.6242 (10) Å
  • β = 106.444 (5)°
  • V = 1631.88 (15) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.07 mm−1
  • T = 295 K
  • 0.53 × 0.35 × 0.15 mm

Data collection

  • Oxford Diffraction Xcalibur Ruby Gemini diffractometer
  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007 [triangle]) T min = 0.881, T max = 0.989
  • 4151 measured reflections
  • 2082 independent reflections
  • 1441 reflections with I > 2σ(I)
  • R int = 0.020

Refinement

  • R[F 2 > 2σ(F 2)] = 0.040
  • wR(F 2) = 0.098
  • S = 0.96
  • 2082 reflections
  • 188 parameters
  • 1 restraint
  • H-atom parameters constrained
  • Δρmax = 0.16 e Å−3
  • Δρmin = −0.12 e Å−3

Data collection: CrysAlis PRO (Oxford Diffraction, 2007 [triangle]); cell refinement: CrysAlis RED (Oxford Diffraction, 2007 [triangle]); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810019720/om2341sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810019720/om2341Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

RJB acknowledges the NSF MRI program (grant No. CHE-0619278) for funds to purchase the X-ray diffractometer. QNMHA thanks R. L. Fine Chem, Bangalore, for the gift sample of the title compound and HSY thanks the University of Mysore for the sanction of sabbatical leave.

supplementary crystallographic information

Comment

The title compound, C19H28O2 (systematic iupac name: (8R,9S,10R,13S,14S)-10,13-Dimethyl-1,2,4,5,6,7,8,9,11,12,14,15,16- tridecahydrocyclopenta[a]phenanthrane-3,17-dione or dodecahydro-10,13-dimethyl-2H-cyclopenta[a]phenanthrene-3,17(4H,14H)-dione) is a derivative of testosterone. The crystal structure of the title compound (CSD code: ANDION10) was first reported by Coiro et al. (1973) with cell parameters of a = 12.700 (20); b = 6.190 (10); c = 21.340 (30) Å; c = 91.27 (10)° and an R-factor of 12% at T = 295 K. These values coincide with those reported earlier (Ohrt et al., 1965). How ever in the present investigations, the cell parameters are a = 12.7786 (6); b = 6.7850 (4); c = 19.6242 (10) Å and β = 106.444 (5)° with an R-factor of 3.86% at 295 K. The crystal structure of 5β-androstane-3,17-dione is already reported (Norton et al., 1962; Anthony et al., 1998). The biotransformation of 5α-androstane-3,17-dione by microalgal cultures is reported (Fiorentino et al., 1991). We have recently reported the crystal structure of 3-oxo-4-aza-5-alpha-androstone-17b-tert -butyl carboxamide (Jasinski et al., 2009). In view of the importance of steroids and taking into account the importance of the title compound, this paper reports the redetermination of its crystal structure with an improved precision.

The title compound, C19H28O2, consists of a cyclopentanone ring (A) fused to to successive cyclohexane (B & C) and cyclohexanone (D) rings. The three cyclohexanone rings are in slightly distorted chair configurations with Cremer & Pople (1975) puckering parameters Q, θ and [var phi] of 0.530 (2) Å, 9.5 (2)° & 3.5 (13)°, for A, 0.5778 (19) Å, 5.77 (19)° & 344.7 (19)°, for B, and 0.5697 (19) Å, 173.01 (19)° & 65.5 (16)°,for C, respectively (Fig. 1). For an ideal chair θ has a value of 0 or 180°. The cyclopentanone ring is a distorted half-chair, phi(2) = 22.5 (3)°. For an ideal half-chair, phi(2) = k x 36 + 18. The crystal packing is stabilized by weak intermolecular C–H···O interactions between a hydrogen atom from the cyclohexanone ring (H5A) with an oxygen atom from a nearby cyclohexanone ring (O1) and between a hydrogen atom from the cyclopentanone ring (H16A) with an oxygen atom from a nearby cyclopentanone ring (O2), respectively (Fig. 2, Table 1).

Experimental

The title compound was obtained as a gift sample from R. L. Fine Chem., Bangalore, India. The compound was used without further purification. X-ray quality crystals were obtained from slow evaporation of acetone solution (m.p.: 373–375 K).

Refinement

All of the H atoms were placed in their calculated positions and then refined using the riding model with C—H = 0.96–0.98 Å, and with Uiso(H) = 1.18–1.50Ueq(C).

Figures

Fig. 1.
Molecular structure of C19H28O2, showing the atom labeling scheme and 50% probability displacement ellipsoids.
Fig. 2.
Packing diagram of the title compound viewed down the b axis.

Crystal data

C19H28O2F(000) = 632
Mr = 288.41Dx = 1.174 Mg m3
Monoclinic, C2Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C 2yCell parameters from 1842 reflections
a = 12.7786 (6) Åθ = 5.1–29.4°
b = 6.7850 (4) ŵ = 0.07 mm1
c = 19.6242 (10) ÅT = 295 K
β = 106.444 (5)°Plate, colorless
V = 1631.88 (15) Å30.53 × 0.35 × 0.15 mm
Z = 4

Data collection

Oxford Diffraction Xcalibur Ruby Gemini diffractometer2082 independent reflections
Radiation source: Enhance (Mo) X-ray Source1441 reflections with I > 2σ(I)
graphiteRint = 0.020
Detector resolution: 10.5081 pixels mm-1θmax = 29.5°, θmin = 5.2°
ω scansh = −17→16
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007)k = −7→9
Tmin = 0.881, Tmax = 0.989l = −22→24
4151 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.098H-atom parameters constrained
S = 0.96w = 1/[σ2(Fo2) + (0.0558P)2] where P = (Fo2 + 2Fc2)/3
2082 reflections(Δ/σ)max < 0.001
188 parametersΔρmax = 0.16 e Å3
1 restraintΔρmin = −0.12 e Å3

Special details

Experimental. In the absence of anolmalous scattering effects Friedel opposites were merged.
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)

xyzUiso*/Ueq
O10.24755 (15)−0.2050 (4)0.04123 (10)0.0831 (6)
O20.70862 (13)0.4649 (3)0.51542 (8)0.0661 (5)
C10.42695 (14)0.2013 (3)0.18578 (9)0.0343 (5)
C20.31200 (15)0.1301 (4)0.18422 (10)0.0463 (6)
H2A0.31860.01440.21410.056*
H2B0.27640.23220.20420.056*
C30.23997 (15)0.0794 (4)0.10955 (11)0.0517 (6)
H3A0.17210.02250.11310.062*
H3B0.22260.19940.08180.062*
C40.29440 (18)−0.0622 (4)0.07223 (11)0.0524 (6)
C50.40981 (16)−0.0152 (4)0.07567 (10)0.0499 (6)
H5A0.41080.09400.04390.060*
H5B0.4423−0.12820.05920.060*
C60.47906 (15)0.0392 (3)0.15109 (10)0.0409 (5)
H6A0.4821−0.07930.18010.049*
C70.59602 (15)0.0857 (4)0.15289 (10)0.0474 (6)
H7A0.59710.20110.12390.057*
H7B0.6262−0.02400.13290.057*
C80.66634 (15)0.1239 (4)0.22867 (10)0.0470 (6)
H8A0.73800.16730.22730.056*
H8B0.67540.00130.25510.056*
C90.61800 (14)0.2786 (3)0.26770 (10)0.0379 (5)
H9A0.61790.40620.24420.045*
C100.49888 (15)0.2242 (3)0.26409 (9)0.0354 (5)
H10A0.50240.09280.28530.043*
C110.44999 (15)0.3593 (4)0.31000 (10)0.0453 (6)
H11A0.43790.48890.28830.054*
H11B0.37970.30710.31080.054*
C120.52271 (16)0.3798 (4)0.38663 (10)0.0494 (6)
H12A0.49080.47430.41200.059*
H12B0.52790.25390.41080.059*
C130.63549 (15)0.4483 (3)0.38639 (9)0.0414 (5)
C140.68430 (14)0.2984 (4)0.34512 (10)0.0407 (5)
H14A0.68120.16980.36720.049*
C150.80574 (15)0.3562 (4)0.36433 (11)0.0566 (7)
H15A0.85040.24570.35830.068*
H15B0.81720.46540.33540.068*
C160.83153 (18)0.4161 (5)0.44290 (11)0.0575 (7)
H16A0.87220.31280.47320.069*
H16B0.87440.53620.45170.069*
C170.72336 (18)0.4479 (4)0.45736 (11)0.0492 (6)
C180.41689 (15)0.3991 (3)0.14581 (8)0.0457 (6)
H18A0.37700.37960.09690.069*
H18B0.48840.44840.14860.069*
H18C0.37900.49230.16700.069*
C190.63290 (18)0.6613 (3)0.35832 (8)0.0579 (6)
H19A0.60020.74650.38560.087*
H19B0.59090.66510.30930.087*
H19C0.70600.70460.36260.087*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0922 (13)0.0866 (15)0.0664 (12)−0.0309 (13)0.0158 (9)−0.0327 (12)
O20.0834 (11)0.0740 (13)0.0335 (8)0.0045 (10)0.0042 (7)−0.0029 (9)
C10.0359 (9)0.0376 (12)0.0287 (10)0.0022 (9)0.0080 (7)0.0006 (9)
C20.0453 (11)0.0547 (16)0.0382 (12)−0.0025 (11)0.0108 (9)−0.0039 (11)
C30.0444 (11)0.0677 (18)0.0398 (12)−0.0127 (12)0.0065 (9)−0.0080 (12)
C40.0608 (13)0.0567 (16)0.0332 (11)−0.0103 (14)0.0029 (9)−0.0024 (12)
C50.0587 (13)0.0544 (16)0.0340 (11)0.0040 (12)0.0090 (9)−0.0069 (11)
C60.0471 (11)0.0378 (12)0.0354 (11)0.0026 (10)0.0079 (8)−0.0010 (10)
C70.0475 (11)0.0560 (16)0.0400 (12)0.0092 (12)0.0148 (9)−0.0080 (11)
C80.0383 (10)0.0544 (15)0.0481 (13)0.0069 (11)0.0117 (9)−0.0061 (11)
C90.0395 (10)0.0398 (13)0.0329 (10)0.0032 (10)0.0077 (8)0.0021 (9)
C100.0400 (10)0.0353 (12)0.0293 (10)0.0012 (9)0.0071 (8)0.0014 (9)
C110.0417 (10)0.0557 (15)0.0386 (11)0.0009 (11)0.0115 (8)−0.0092 (11)
C120.0562 (12)0.0582 (16)0.0351 (11)0.0015 (12)0.0150 (9)−0.0058 (11)
C130.0488 (11)0.0417 (13)0.0293 (10)0.0016 (11)0.0041 (8)−0.0008 (10)
C140.0426 (10)0.0389 (12)0.0371 (11)0.0008 (11)0.0056 (8)0.0035 (10)
C150.0448 (11)0.073 (2)0.0465 (12)−0.0008 (12)0.0040 (9)0.0025 (13)
C160.0530 (12)0.0652 (18)0.0446 (12)−0.0114 (13)−0.0020 (9)0.0021 (13)
C170.0635 (14)0.0407 (14)0.0354 (12)−0.0027 (12)0.0012 (9)0.0036 (11)
C180.0497 (11)0.0443 (14)0.0389 (11)0.0036 (11)0.0055 (8)0.0035 (11)
C190.0737 (15)0.0435 (14)0.0460 (14)−0.0014 (14)0.0000 (11)−0.0005 (12)

Geometric parameters (Å, °)

O1—C41.209 (3)C9—H9A0.9800
O2—C171.212 (2)C10—C111.536 (3)
C1—C21.538 (3)C10—H10A0.9800
C1—C61.541 (3)C11—C121.534 (3)
C1—C181.541 (3)C11—H11A0.9700
C1—C101.559 (2)C11—H11B0.9700
C2—C31.533 (3)C12—C131.515 (3)
C2—H2A0.9700C12—H12A0.9700
C2—H2B0.9700C12—H12B0.9700
C3—C41.494 (3)C13—C171.521 (3)
C3—H3A0.9700C13—C141.538 (3)
C3—H3B0.9700C13—C191.544
C4—C51.492 (3)C14—C151.540 (3)
C5—C61.539 (3)C14—H14A0.9800
C5—H5A0.9700C15—C161.538 (3)
C5—H5B0.9700C15—H15A0.9700
C6—C71.518 (3)C15—H15B0.9700
C6—H6A0.9800C16—C171.503 (3)
C7—C81.526 (3)C16—H16A0.9700
C7—H7A0.9700C16—H16B0.9700
C7—H7B0.9700C18—H18A0.9600
C8—C91.529 (3)C18—H18B0.9600
C8—H8A0.9700C18—H18C0.9600
C8—H8B0.9700C19—H19A0.9600
C9—C141.522 (2)C19—H19B0.9600
C9—C101.548 (2)C19—H19C0.9600
C2—C1—C6107.26 (17)C11—C10—H10A105.7
C2—C1—C18108.76 (16)C9—C10—H10A105.7
C6—C1—C18112.39 (15)C1—C10—H10A105.7
C2—C1—C10110.12 (14)C12—C11—C10113.26 (16)
C6—C1—C10107.39 (15)C12—C11—H11A108.9
C18—C1—C10110.84 (16)C10—C11—H11A108.9
C3—C2—C1113.65 (15)C12—C11—H11B108.9
C3—C2—H2A108.8C10—C11—H11B108.9
C1—C2—H2A108.8H11A—C11—H11B107.7
C3—C2—H2B108.8C13—C12—C11109.73 (15)
C1—C2—H2B108.8C13—C12—H12A109.7
H2A—C2—H2B107.7C11—C12—H12A109.7
C4—C3—C2112.10 (18)C13—C12—H12B109.7
C4—C3—H3A109.2C11—C12—H12B109.7
C2—C3—H3A109.2H12A—C12—H12B108.2
C4—C3—H3B109.2C12—C13—C17116.93 (17)
C2—C3—H3B109.2C12—C13—C14109.07 (18)
H3A—C3—H3B107.9C17—C13—C14100.18 (16)
O1—C4—C5122.5 (2)C12—C13—C19111.32
O1—C4—C3122.0 (2)C17—C13—C19105.30
C5—C4—C3115.6 (2)C14—C13—C19113.70
C4—C5—C6112.76 (16)C9—C14—C13112.95 (16)
C4—C5—H5A109.0C9—C14—C15120.29 (16)
C6—C5—H5A109.0C13—C14—C15103.50 (18)
C4—C5—H5B109.0C9—C14—H14A106.4
C6—C5—H5B109.0C13—C14—H14A106.4
H5A—C5—H5B107.8C15—C14—H14A106.4
C7—C6—C5111.51 (16)C16—C15—C14103.17 (17)
C7—C6—C1112.77 (17)C16—C15—H15A111.1
C5—C6—C1113.16 (16)C14—C15—H15A111.1
C7—C6—H6A106.3C16—C15—H15B111.1
C5—C6—H6A106.3C14—C15—H15B111.1
C1—C6—H6A106.3H15A—C15—H15B109.1
C6—C7—C8111.24 (16)C17—C16—C15106.24 (17)
C6—C7—H7A109.4C17—C16—H16A110.5
C8—C7—H7A109.4C15—C16—H16A110.5
C6—C7—H7B109.4C17—C16—H16B110.5
C8—C7—H7B109.4C15—C16—H16B110.5
H7A—C7—H7B108.0H16A—C16—H16B108.7
C7—C8—C9113.24 (17)O2—C17—C16125.95 (19)
C7—C8—H8A108.9O2—C17—C13126.1 (2)
C9—C8—H8A108.9C16—C17—C13107.90 (17)
C7—C8—H8B108.9C1—C18—H18A109.5
C9—C8—H8B108.9C1—C18—H18B109.5
H8A—C8—H8B107.7H18A—C18—H18B109.5
C14—C9—C8111.77 (16)C1—C18—H18C109.5
C14—C9—C10109.20 (14)H18A—C18—H18C109.5
C8—C9—C10110.16 (17)H18B—C18—H18C109.5
C14—C9—H9A108.5C13—C19—H19A109.5
C8—C9—H9A108.5C13—C19—H19B109.4
C10—C9—H9A108.5H19A—C19—H19B109.5
C11—C10—C9112.88 (16)C13—C19—H19C109.5
C11—C10—C1114.42 (15)H19A—C19—H19C109.5
C9—C10—C1111.49 (14)H19B—C19—H19C109.5
C6—C1—C2—C3−56.4 (3)C6—C1—C10—C958.7 (2)
C18—C1—C2—C365.4 (2)C18—C1—C10—C9−64.4 (2)
C10—C1—C2—C3−173.0 (2)C9—C10—C11—C12−50.8 (2)
C1—C2—C3—C452.7 (3)C1—C10—C11—C12−179.73 (17)
C2—C3—C4—O1133.4 (2)C10—C11—C12—C1354.9 (3)
C2—C3—C4—C5−46.8 (3)C11—C12—C13—C17−171.28 (19)
O1—C4—C5—C6−133.6 (2)C11—C12—C13—C14−58.6 (2)
C3—C4—C5—C646.6 (3)C11—C12—C13—C1967.6
C4—C5—C6—C7179.9 (2)C8—C9—C14—C13−178.12 (18)
C4—C5—C6—C1−51.8 (3)C10—C9—C14—C13−56.0 (2)
C2—C1—C6—C7−176.75 (16)C8—C9—C14—C1559.1 (3)
C18—C1—C6—C763.8 (2)C10—C9—C14—C15−178.7 (2)
C10—C1—C6—C7−58.4 (2)C12—C13—C14—C961.7 (2)
C2—C1—C6—C555.5 (2)C17—C13—C14—C9−175.01 (17)
C18—C1—C6—C5−64.0 (2)C19—C13—C14—C9−63.2
C10—C1—C6—C5173.87 (17)C12—C13—C14—C15−166.62 (17)
C5—C6—C7—C8−175.6 (2)C17—C13—C14—C15−43.3 (2)
C1—C6—C7—C855.8 (2)C19—C13—C14—C1568.5
C6—C7—C8—C9−52.4 (3)C9—C14—C15—C16164.6 (2)
C7—C8—C9—C14174.44 (19)C13—C14—C15—C1637.4 (2)
C7—C8—C9—C1052.8 (2)C14—C15—C16—C17−16.2 (3)
C14—C9—C10—C1149.8 (2)C15—C16—C17—O2167.1 (3)
C8—C9—C10—C11172.87 (17)C15—C16—C17—C13−11.1 (3)
C14—C9—C10—C1−179.82 (18)C12—C13—C17—O2−27.0 (3)
C8—C9—C10—C1−56.7 (2)C14—C13—C17—O2−144.6 (3)
C2—C1—C10—C11−55.2 (2)C19—C13—C17—O297.2
C6—C1—C10—C11−171.69 (18)C12—C13—C17—C16151.2 (2)
C18—C1—C10—C1165.2 (2)C14—C13—C17—C1633.6 (2)
C2—C1—C10—C9175.18 (19)C19—C13—C17—C16−84.6

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C16—H16A···O2i0.972.613.247 (3)123
C5—H5A···O1ii0.972.613.335 (3)131

Symmetry codes: (i) −x+3/2, y−1/2, −z+1; (ii) −x+1/2, y+1/2, −z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: OM2341).

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