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Acta Crystallogr Sect E Struct Rep Online. 2009 May 1; 65(Pt 5): o1102.
Published online 2009 April 25. doi:  10.1107/S1600536809013853
PMCID: PMC2977780

3β,12β,14α-Trihydroxy­pregnan-20-one

Abstract

The title compound, C21H34O4, is a steriod of the pregnane family prepared by the sequential oxidation and reduction of 3β,12β-diacet­oxy-20-ethyl­enedioxy­pregnan-14-ene. The con­formations of the six-membered rings are close to chair forms, while the five-membered ring adopts an envelope conformation. All the rings are trans-fused and an intra­molecular O—H(...)O hydrogen bond occurs. In the crystal structure, inter­molecular O—H(...)O hydrogen bonds link the mol­ecules into a two-dimensional network.

Related literature

For the synthesis, see: Templeton & Yan (1992 [triangle]); Fell & Heathcock (2002 [triangle]). For background on hecogenin, see: Ranu & Samanta (2003 [triangle]).

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Object name is e-65-o1102-scheme1.jpg

Experimental

Crystal data

  • C21H34O4
  • M r = 350.48
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1102-efi1.jpg
  • a = 6.1364 (7) Å
  • b = 12.1472 (13) Å
  • c = 12.7593 (14) Å
  • β = 101.513 (2)°
  • V = 931.94 (18) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.08 mm−1
  • T = 293 K
  • 0.50 × 0.44 × 0.32 mm

Data collection

  • Bruker SMART CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 1998 [triangle]) T min = 0.729, T max = 0.97
  • 5569 measured reflections
  • 2194 independent reflections
  • 1930 reflections with I > 2σ(I)
  • R int = 0.107

Refinement

  • R[F 2 > 2σ(F 2)] = 0.048
  • wR(F 2) = 0.125
  • S = 1.01
  • 2194 reflections
  • 238 parameters
  • 1 restraint
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.28 e Å−3
  • Δρmin = −0.24 e Å−3

Data collection: SMART (Bruker, 1998 [triangle]); cell refinement: SAINT (Bruker, 1998 [triangle]); data reduction: SAINT; 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.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809013853/hb2940sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809013853/hb2940Isup2.hkl

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

Acknowledgments

The authors acknowledge financial support from the National Natural Science Foundation of China (grant No. 30572245).

supplementary crystallographic information

Comment

The title compound was obtained by oxidation and reduction of the corresponding 3β,12β-diacetoxypregnan-20-ethylenedioxy-14-ene, which was prepared from hecogenin (Fell & Heathcock, 2002; Ranu & Samanta, 2003). We have undertaken the X-ray crystal structure determination of (I) in order to establish its molecular conformation and relative stereochemistry.

The hydroxyl group at C12 and the acetyl group at C17 are beta-oriented respectively, whereas the hydroxyl group at C14 is alpha-oriented (Fig. 1). The conformation of the six-membered rings in both molecules are close to chair forms, while the five-membered ring adopts an envelope conformation. All rings in both molecules are trans-fused. The molecules of (I) are held together by an extensive O—H···O hydrogen-bonding two-dimensional network (Table 1, Fig. 2).

Experimental

The title compound was prepared according to the literature method (Fell & Heathcock, 2002; Templeton & Yan 1992). Crystals suitable for X-ray analysis were obtained by slow evaporation of a methanol solution at room temperature (m.p. 343–347 K).

Refinement

Anomalous dispersion was negligible and Friedel pairs were merged before refinement. The O-bond H atoms were located in a difference map and their positions were freely refined with Uiso(H) = 1.5Ueq(O). The C-bound H atoms were fixed geometrically at ideal positions (C—H = 0.96–0.98 Å) and refined as riding with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C).

Figures

Fig. 1.
The molecular structure of (I) with displacement ellipsoids for the non-H atoms drawn at the 50% probability level.
Fig. 2.
The molecular packing of (I) viewed down the a axis. Dashed lines indicate hydrogen bonds.

Crystal data

C21H34O4F(000) = 384
Mr = 350.48Dx = 1.249 Mg m3
Monoclinic, P21Melting point: 431(2) K
Hall symbol: P 2ybMo Kα radiation, λ = 0.71073 Å
a = 6.1364 (7) ÅCell parameters from 2719 reflections
b = 12.1472 (13) Åθ = 4.7–55.9°
c = 12.7593 (14) ŵ = 0.08 mm1
β = 101.513 (2)°T = 293 K
V = 931.94 (18) Å3Prism, colourless
Z = 20.50 × 0.44 × 0.32 mm

Data collection

Bruker SMART CCD area-detector diffractometer2194 independent reflections
Radiation source: fine-focus sealed tube1930 reflections with I > 2σ(I)
graphiteRint = 0.107
ω scansθmax = 27.5°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Bruker, 1998)h = −7→7
Tmin = 0.729, Tmax = 0.97k = −15→13
5569 measured reflectionsl = −16→13

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)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.125H atoms treated by a mixture of independent and constrained refinement
S = 1.01w = 1/[σ2(Fo2) + (0.0733P)2] where P = (Fo2 + 2Fc2)/3
2194 reflections(Δ/σ)max < 0.001
238 parametersΔρmax = 0.28 e Å3
1 restraintΔρmin = −0.24 e Å3

Special details

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
O10.2262 (4)−0.0588 (2)−0.28839 (15)0.0605 (6)
H10.152 (7)−0.121 (5)−0.292 (3)0.091*
O20.9924 (3)0.22625 (16)0.32210 (14)0.0440 (4)
H21.062 (6)0.223 (4)0.382 (3)0.066*
O30.7898 (3)−0.09548 (15)0.33306 (15)0.0455 (5)
H30.767 (6)−0.146 (4)0.371 (3)0.068*
O41.1201 (4)0.2028 (2)0.54187 (16)0.0695 (7)
C10.5918 (4)0.0590 (2)−0.04305 (19)0.0439 (6)
H1A0.66050.1311−0.03170.053*
H1B0.70990.0046−0.03160.053*
C20.4657 (5)0.0512 (3)−0.1588 (2)0.0503 (6)
H2A0.35930.1111−0.17350.060*
H2B0.56950.0587−0.20660.060*
C30.3446 (5)−0.0573 (2)−0.18001 (19)0.0476 (6)
H3A0.4549−0.1166−0.17040.057*
C40.1926 (4)−0.0747 (2)−0.1019 (2)0.0457 (6)
H4A0.1198−0.1456−0.11500.055*
H4B0.0785−0.0182−0.11240.055*
C50.3237 (4)−0.07015 (19)0.01358 (19)0.0384 (5)
H50.4398−0.12650.01940.046*
C60.1835 (5)−0.1005 (2)0.0945 (2)0.0479 (6)
H6A0.1104−0.17040.07480.057*
H6B0.0693−0.04510.09370.057*
C70.3245 (5)−0.1090 (2)0.2067 (2)0.0470 (6)
H7A0.4239−0.17150.21000.056*
H7B0.2283−0.12160.25730.056*
C80.4612 (4)−0.0048 (2)0.23833 (18)0.0355 (5)
H80.35770.05510.24490.043*
C90.5946 (4)0.02912 (18)0.15366 (17)0.0317 (5)
H90.6985−0.03120.14920.038*
C100.4450 (4)0.04102 (19)0.04009 (18)0.0345 (5)
C110.7364 (4)0.1310 (2)0.19024 (19)0.0359 (5)
H11A0.83190.14470.13960.043*
H11B0.63850.19390.18830.043*
C120.8806 (4)0.12266 (18)0.30152 (19)0.0348 (5)
H120.99220.06510.30100.042*
C130.7415 (4)0.09215 (19)0.38462 (19)0.0348 (5)
C140.6210 (4)−0.01731 (19)0.34639 (18)0.0361 (5)
C150.5234 (5)−0.0524 (2)0.44230 (19)0.0473 (6)
H15A0.5004−0.13140.44230.057*
H15B0.3827−0.01580.44170.057*
C160.6988 (5)−0.0170 (3)0.5398 (2)0.0541 (7)
H16A0.7707−0.08100.57690.065*
H16B0.62970.02490.58920.065*
C170.8697 (4)0.0546 (2)0.49776 (19)0.0403 (5)
H170.98850.00510.48580.048*
C180.5805 (4)0.1853 (2)0.3979 (2)0.0424 (6)
H18A0.66350.25060.42240.064*
H18B0.49340.16380.44920.064*
H18C0.48370.19980.33040.064*
C190.2822 (4)0.1371 (2)0.0358 (2)0.0448 (6)
H19A0.36060.20530.03470.067*
H19B0.21530.13500.09770.067*
H19C0.16850.1313−0.02760.067*
C200.9805 (4)0.1466 (2)0.5690 (2)0.0438 (6)
C210.9195 (6)0.1652 (3)0.6749 (2)0.0545 (7)
H21A1.01510.22050.71350.082*
H21B0.93640.09780.71500.082*
H21C0.76780.18940.66450.082*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0810 (15)0.0551 (12)0.0400 (9)−0.0012 (12)−0.0008 (9)−0.0079 (9)
O20.0463 (10)0.0431 (9)0.0411 (9)−0.0159 (8)0.0053 (7)0.0008 (8)
O30.0571 (11)0.0313 (8)0.0501 (10)0.0073 (8)0.0156 (8)0.0067 (7)
O40.0806 (15)0.0832 (17)0.0480 (11)−0.0383 (14)0.0209 (10)−0.0205 (10)
C10.0452 (13)0.0503 (14)0.0374 (12)−0.0085 (12)0.0109 (10)0.0003 (11)
C20.0565 (16)0.0568 (15)0.0380 (12)−0.0097 (14)0.0106 (11)0.0009 (11)
C30.0550 (15)0.0472 (14)0.0383 (12)0.0041 (13)0.0036 (11)−0.0058 (11)
C40.0495 (14)0.0386 (13)0.0471 (13)−0.0047 (11)0.0047 (11)−0.0069 (10)
C50.0405 (12)0.0307 (11)0.0441 (12)−0.0020 (10)0.0087 (10)−0.0033 (9)
C60.0463 (14)0.0444 (14)0.0533 (14)−0.0170 (12)0.0108 (11)−0.0031 (12)
C70.0540 (15)0.0400 (13)0.0491 (14)−0.0182 (12)0.0154 (11)0.0018 (11)
C80.0374 (11)0.0306 (10)0.0412 (11)−0.0044 (9)0.0142 (9)0.0002 (9)
C90.0316 (11)0.0288 (10)0.0362 (10)−0.0017 (9)0.0103 (8)−0.0013 (8)
C100.0365 (12)0.0303 (11)0.0376 (11)−0.0008 (9)0.0092 (8)−0.0005 (9)
C110.0372 (11)0.0335 (11)0.0393 (11)−0.0070 (10)0.0132 (9)0.0013 (9)
C120.0329 (11)0.0345 (12)0.0391 (11)−0.0029 (10)0.0120 (9)−0.0006 (9)
C130.0374 (11)0.0324 (10)0.0369 (11)−0.0013 (10)0.0129 (9)−0.0017 (9)
C140.0384 (12)0.0314 (11)0.0416 (12)−0.0031 (10)0.0155 (9)0.0008 (9)
C150.0569 (15)0.0443 (13)0.0441 (13)−0.0121 (12)0.0178 (11)0.0053 (11)
C160.0656 (17)0.0578 (16)0.0401 (13)−0.0111 (15)0.0134 (12)0.0057 (12)
C170.0461 (13)0.0412 (12)0.0343 (11)−0.0013 (11)0.0098 (9)−0.0007 (10)
C180.0419 (13)0.0385 (12)0.0505 (13)0.0019 (11)0.0183 (10)−0.0062 (10)
C190.0465 (13)0.0331 (11)0.0528 (14)0.0037 (11)0.0047 (11)−0.0009 (11)
C200.0483 (13)0.0439 (13)0.0397 (12)−0.0006 (12)0.0098 (10)−0.0033 (10)
C210.0740 (18)0.0466 (15)0.0462 (14)0.0022 (14)0.0200 (13)−0.0081 (12)

Geometric parameters (Å, °)

O1—C31.428 (3)C9—C111.531 (3)
O1—H10.88 (5)C9—C101.560 (3)
O2—C121.432 (3)C9—H90.9800
O2—H20.80 (4)C10—C191.530 (3)
O3—C141.440 (3)C11—C121.519 (3)
O3—H30.81 (4)C11—H11A0.9700
O4—C201.200 (3)C11—H11B0.9700
C1—C21.528 (3)C12—C131.533 (3)
C1—C101.538 (3)C12—H120.9800
C1—H1A0.9700C13—C181.534 (3)
C1—H1B0.9700C13—C141.552 (3)
C2—C31.510 (4)C13—C171.568 (3)
C2—H2A0.9700C14—C151.527 (3)
C2—H2B0.9700C15—C161.536 (4)
C3—C41.510 (4)C15—H15A0.9700
C3—H3A0.9800C15—H15B0.9700
C4—C51.532 (3)C16—C171.539 (4)
C4—H4A0.9700C16—H16A0.9700
C4—H4B0.9700C16—H16B0.9700
C5—C61.515 (3)C17—C201.513 (4)
C5—C101.546 (3)C17—H170.9800
C5—H50.9800C18—H18A0.9600
C6—C71.521 (4)C18—H18B0.9600
C6—H6A0.9700C18—H18C0.9600
C6—H6B0.9700C19—H19A0.9600
C7—C81.528 (3)C19—H19B0.9600
C7—H7A0.9700C19—H19C0.9600
C7—H7B0.9700C20—C211.489 (4)
C8—C141.532 (3)C21—H21A0.9600
C8—C91.536 (3)C21—H21B0.9600
C8—H80.9800C21—H21C0.9600
C3—O1—H1103 (3)C12—C11—C9114.89 (18)
C12—O2—H2106 (3)C12—C11—H11A108.5
C14—O3—H3102 (3)C9—C11—H11A108.5
C2—C1—C10113.85 (19)C12—C11—H11B108.5
C2—C1—H1A108.8C9—C11—H11B108.5
C10—C1—H1A108.8H11A—C11—H11B107.5
C2—C1—H1B108.8O2—C12—C11106.34 (17)
C10—C1—H1B108.8O2—C12—C13113.46 (19)
H1A—C1—H1B107.7C11—C12—C13111.22 (18)
C3—C2—C1111.3 (2)O2—C12—H12108.6
C3—C2—H2A109.4C11—C12—H12108.6
C1—C2—H2A109.4C13—C12—H12108.6
C3—C2—H2B109.4C12—C13—C18110.96 (19)
C1—C2—H2B109.4C12—C13—C14106.61 (18)
H2A—C2—H2B108.0C18—C13—C14112.93 (19)
O1—C3—C4112.1 (2)C12—C13—C17117.45 (19)
O1—C3—C2108.8 (2)C18—C13—C17109.21 (19)
C4—C3—C2110.5 (2)C14—C13—C1799.21 (18)
O1—C3—H3A108.5O3—C14—C15108.5 (2)
C4—C3—H3A108.5O3—C14—C8107.79 (18)
C2—C3—H3A108.5C15—C14—C8117.80 (19)
C3—C4—C5110.8 (2)O3—C14—C13107.04 (18)
C3—C4—H4A109.5C15—C14—C13103.07 (18)
C5—C4—H4A109.5C8—C14—C13112.14 (19)
C3—C4—H4B109.5C14—C15—C16104.3 (2)
C5—C4—H4B109.5C14—C15—H15A110.9
H4A—C4—H4B108.1C16—C15—H15A110.9
C6—C5—C4112.7 (2)C14—C15—H15B110.9
C6—C5—C10112.1 (2)C16—C15—H15B110.9
C4—C5—C10112.28 (19)H15A—C15—H15B108.9
C6—C5—H5106.4C15—C16—C17107.0 (2)
C4—C5—H5106.4C15—C16—H16A110.3
C10—C5—H5106.4C17—C16—H16A110.3
C5—C6—C7111.4 (2)C15—C16—H16B110.3
C5—C6—H6A109.4C17—C16—H16B110.3
C7—C6—H6A109.4H16A—C16—H16B108.6
C5—C6—H6B109.4C20—C17—C16117.6 (2)
C7—C6—H6B109.4C20—C17—C13114.9 (2)
H6A—C6—H6B108.0C16—C17—C13103.5 (2)
C6—C7—C8111.8 (2)C20—C17—H17106.7
C6—C7—H7A109.3C16—C17—H17106.7
C8—C7—H7A109.3C13—C17—H17106.7
C6—C7—H7B109.3C13—C18—H18A109.5
C8—C7—H7B109.3C13—C18—H18B109.5
H7A—C7—H7B107.9H18A—C18—H18B109.5
C7—C8—C14112.00 (19)C13—C18—H18C109.5
C7—C8—C9112.19 (19)H18A—C18—H18C109.5
C14—C8—C9108.93 (17)H18B—C18—H18C109.5
C7—C8—H8107.8C10—C19—H19A109.5
C14—C8—H8107.8C10—C19—H19B109.5
C9—C8—H8107.8H19A—C19—H19B109.5
C11—C9—C8110.64 (17)C10—C19—H19C109.5
C11—C9—C10113.70 (18)H19A—C19—H19C109.5
C8—C9—C10112.37 (17)H19B—C19—H19C109.5
C11—C9—H9106.5O4—C20—C21119.9 (3)
C8—C9—H9106.5O4—C20—C17120.5 (2)
C10—C9—H9106.5C21—C20—C17119.6 (2)
C19—C10—C1109.6 (2)C20—C21—H21A109.5
C19—C10—C5112.09 (18)C20—C21—H21B109.5
C1—C10—C5107.21 (19)H21A—C21—H21B109.5
C19—C10—C9111.28 (19)C20—C21—H21C109.5
C1—C10—C9109.66 (17)H21A—C21—H21C109.5
C5—C10—C9106.91 (18)H21B—C21—H21C109.5
C10—C1—C2—C3−55.5 (3)C11—C12—C13—C18−66.8 (2)
C1—C2—C3—O1178.7 (2)O2—C12—C13—C14176.39 (17)
C1—C2—C3—C455.3 (3)C11—C12—C13—C1456.5 (2)
O1—C3—C4—C5−178.8 (2)O2—C12—C13—C17−73.5 (3)
C2—C3—C4—C5−57.3 (3)C11—C12—C13—C17166.6 (2)
C3—C4—C5—C6−173.2 (2)C7—C8—C14—O368.6 (2)
C3—C4—C5—C1059.0 (3)C9—C8—C14—O3−56.1 (2)
C4—C5—C6—C7173.0 (2)C7—C8—C14—C15−54.5 (3)
C10—C5—C6—C7−59.2 (3)C9—C8—C14—C15−179.1 (2)
C5—C6—C7—C853.6 (3)C7—C8—C14—C13−173.83 (19)
C6—C7—C8—C14−174.2 (2)C9—C8—C14—C1361.5 (2)
C6—C7—C8—C9−51.3 (3)C12—C13—C14—O355.5 (2)
C7—C8—C9—C11−177.7 (2)C18—C13—C14—O3177.62 (18)
C14—C8—C9—C11−53.1 (2)C17—C13—C14—O3−66.9 (2)
C7—C8—C9—C1054.0 (2)C12—C13—C14—C15169.8 (2)
C14—C8—C9—C10178.61 (19)C18—C13—C14—C15−68.1 (2)
C2—C1—C10—C19−67.9 (3)C17—C13—C14—C1547.4 (2)
C2—C1—C10—C553.9 (3)C12—C13—C14—C8−62.5 (2)
C2—C1—C10—C9169.6 (2)C18—C13—C14—C859.6 (2)
C6—C5—C10—C19−63.2 (3)C17—C13—C14—C8175.10 (18)
C4—C5—C10—C1964.9 (3)O3—C14—C15—C1677.3 (3)
C6—C5—C10—C1176.6 (2)C8—C14—C15—C16−160.0 (2)
C4—C5—C10—C1−55.4 (2)C13—C14—C15—C16−35.9 (3)
C6—C5—C10—C959.0 (2)C14—C15—C16—C179.7 (3)
C4—C5—C10—C9−172.89 (18)C15—C16—C17—C20147.8 (2)
C11—C9—C10—C19−60.2 (2)C15—C16—C17—C1319.9 (3)
C8—C9—C10—C1966.4 (2)C12—C13—C17—C2075.4 (3)
C11—C9—C10—C161.2 (2)C18—C13—C17—C20−52.0 (3)
C8—C9—C10—C1−172.2 (2)C14—C13—C17—C20−170.3 (2)
C11—C9—C10—C5177.11 (18)C12—C13—C17—C16−155.0 (2)
C8—C9—C10—C5−56.2 (2)C18—C13—C17—C1677.6 (3)
C8—C9—C11—C1251.3 (2)C14—C13—C17—C16−40.8 (2)
C10—C9—C11—C12178.83 (19)C16—C17—C20—O4177.7 (3)
C9—C11—C12—O2−177.92 (18)C13—C17—C20—O4−60.1 (3)
C9—C11—C12—C13−53.9 (2)C16—C17—C20—C21−0.7 (4)
O2—C12—C13—C1853.0 (3)C13—C17—C20—C21121.5 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O3—H3···O4i0.81 (4)2.19 (4)2.916 (3)150 (3)
O2—H2···O40.80 (4)2.01 (4)2.771 (3)158 (3)
O1—H1···O2ii0.88 (5)2.05 (6)2.928 (3)170 (4)

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HB2940).

References

  • Bruker (1998). SMART, SAINT and SADABS Bruker AXS Inc., Madison, Wisconsin, USA.
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  • Ranu, B. C. & Samanta, S. (2003). J. Org. Chem.68, 7130–7132. [PubMed]
  • Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]
  • Templeton, J. F. & Yan, Y. (1992). Org. Prep. Proced. Int.24, 159–163.

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