supplementary materials


lr2076 scheme

Acta Cryst. (2013). E69, o313    [ doi:10.1107/S1600536813002493 ]

3[beta]-Acetoxy-19-hydroxy-[Delta]5-pregnen-20-one

A. Meier zu Greffen, D. P. Kranz, J.-M. Neudörfl and H.-G. Schmalz

Abstract top

In the title compound, C23H34O4, the C/D and D/E rings are trans fused and the A/B ring possesses an anti fusion. The two cyclohexane rings adopt a chair conformation while the cyclohexene ring exhibits a half-chair conformation. The cyclopentane ring displays an envelope conformation with the C atom bearing the methyl group as the flap. In the crystal, the molecules are linked by O-H...O hydrogen bonds, forming chains along the b axis.

Comment top

The structural diversity of steroids as well as their unsurpassed biological potential qualify them as challenging targets for chemical synthesis and as lead structures for pharmacological research (Fieser & Fieser, 1961; Hanson, 2010). In recent years, some unusual steroids displaying a rearranged A/B-ring system with promising biological properties have been reported (Du et al., 2008; Aoki et al., 2006; Flyer et al., 2010). Important intermediates for the synthesis of such rearranged derivatives are C-19 functionalized steroids (El Sheikh et al., 2007; Shenvi et al., 2008). The functionalization of the unactivated angular C-10 methyl group is achieved by remote functionalization (Heusler et al., 1964; Reese, 2001). During our synthesis of diverse B-homo-steroids the C-19-hydroxy-steroid (I) was isolated as an intermediate (Kranz et al., 2011). The C/D and D/E rings in C23H34O4 are trans fused and the A/B ring possesses an anti fusion. The A ring and the C ring adopt a chair conformation, while the other six membered B ring displays a half chair conformation (Fig. 1). In the five membered ring, the atoms show an envelope conformation and C14/C15/C16/C17 are nearly coplanar while the C13 deviates from the plane by 0.726 (2) Å. The C(5)–C(10)–C(19)–O(3) torsion angle is -165.71 (16)° and the torsion angles C(4)–C(5)–C(10)–C(1) with -45.0 (2)°, C(1)–C(10)–C(9)–C(11) with 68.3 (2)° and C(8)–C(14)–C(13)–C(12) with -58.9 (2)° are within the average range (Allen, 2002). The molecules are linked by O–H···O hydrogen bonds between the C19 hydroxy group of one steroid to the ester carbonyl oxygen of the next steroid, forming chain networks along the b axis. These chain networks generate layer structures parallel to the c axis (Fig. 2).

Related literature top

For an overview of steroids as biologically important molecules, see: Fieser & Fieser (1961); Hanson (2010). For examples of steroids possessing a rearranged A/B-ring system, see: Du et al. (2008); Aoki et al. (2006); Flyer et al. (2010). For related C-19-functionalized steroids, see: El Sheikh et al. (2007); Shenvi et al. (2008). For an overview of remote functionalization, see: Reese (2001); Heusler & Kalvoda (1964). For the first synthesis of the title compound, see: Halpern et al. (1963). For examples of the title compound as an intermediate for rearranged A/B-ring systems, see: Knox et al. (1965); Kranz et al. (2011). For a description of the Cambridge Structural Database, see: Allen (2002).

Experimental top

The title compound C23H34O4 was prepared in 3 steps starting from commercial pregnenolone-acetate (Kranz et al., 2011).

Refinement top

All hydrogen atoms were placed in geometrically idealized positions and refined with using riding model with C—H = 0.95 Å and Uiso(H) = 1.2Ueq(C) for CH, C—H = 0.99 Å and Uiso(H) = 1.2Ueq(C) for CH2, C—H = 0.98 Å and Uiso(H) = 1.5Ueq(C) for CH3 and OH.

Computing details top

Data collection: COLLECT (Hooft 1998); cell refinement: DENZO (Otwinowski & Minor, 1997); data reduction: DENZO (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SCHAKAL99 (Keller, 1999); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. Plot of the unit cell; the b axis is perpendicular to the plane of the paper and the a and c axes are horizontal and vertical, respectively.
3β-Acetoxy-19-hydroxy-Δ5-pregnen-20-one top
Crystal data top
C23H34O4F(000) = 816
Mr = 374.50Dx = 1.261 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 9889 reflections
a = 8.6960 (6) Åθ = 2.0–27.0°
b = 12.3708 (4) ŵ = 0.08 mm1
c = 18.3303 (10) ÅT = 100 K
V = 1971.91 (18) Å3Prism, colourless
Z = 40.3 × 0.3 × 0.3 mm
Data collection top
Nonius KappaCCD
diffractometer
1943 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.044
Graphite monochromatorθmax = 27.0°, θmin = 2.0°
Phi/ω–Scans scansh = 611
9889 measured reflectionsk = 1215
2457 independent reflectionsl = 2123
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)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.079H-atom parameters constrained
S = 0.99 w = 1/[σ2(Fo2) + (0.0425P)2]
where P = (Fo2 + 2Fc2)/3
2457 reflections(Δ/σ)max < 0.001
247 parametersΔρmax = 0.23 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C23H34O4V = 1971.91 (18) Å3
Mr = 374.50Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 8.6960 (6) ŵ = 0.08 mm1
b = 12.3708 (4) ÅT = 100 K
c = 18.3303 (10) Å0.3 × 0.3 × 0.3 mm
Data collection top
Nonius KappaCCD
diffractometer
1943 reflections with I > 2σ(I)
9889 measured reflectionsRint = 0.044
2457 independent reflectionsθmax = 27.0°
Refinement top
R[F2 > 2σ(F2)] = 0.037H-atom parameters constrained
wR(F2) = 0.079Δρmax = 0.23 e Å3
S = 0.99Δρmin = 0.23 e Å3
2457 reflectionsAbsolute structure: ?
247 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
O10.03545 (17)0.54114 (10)0.67613 (8)0.0195 (3)
O20.13591 (19)0.70584 (11)0.65410 (8)0.0267 (4)
O30.20344 (19)0.38623 (10)0.94444 (8)0.0246 (4)
H3A0.14810.34670.91800.037*
O40.0183 (2)0.54920 (11)1.30301 (9)0.0360 (5)
C10.0748 (2)0.47261 (15)0.87606 (11)0.0170 (5)
H1A0.07080.40210.90160.020*
H1B0.17890.50300.88360.020*
C20.0516 (3)0.45275 (14)0.79398 (11)0.0182 (5)
H2A0.04810.41610.78560.022*
H2B0.13450.40550.77520.022*
C30.0541 (3)0.55950 (14)0.75430 (11)0.0180 (5)
H30.15470.59640.76340.022*
C40.0760 (3)0.63061 (15)0.78170 (11)0.0188 (5)
H4A0.17580.59530.77130.023*
H4B0.07380.70070.75570.023*
C50.0611 (2)0.64986 (15)0.86293 (11)0.0165 (5)
C60.0610 (3)0.75048 (15)0.88802 (11)0.0172 (5)
H60.06820.80720.85320.021*
C70.0504 (3)0.78158 (14)0.96614 (11)0.0172 (5)
H7A0.05100.81550.97510.021*
H7B0.13060.83600.97690.021*
C80.0700 (3)0.68595 (14)1.01773 (11)0.0160 (5)
H80.18190.66831.02160.019*
C90.0163 (2)0.58588 (14)0.98836 (11)0.0165 (5)
H90.12520.60930.98070.020*
C100.0442 (2)0.54967 (14)0.91196 (11)0.0161 (5)
C110.0222 (3)0.49458 (14)1.04593 (11)0.0193 (5)
H20A0.08940.43591.02770.023*
H20B0.08250.46441.05220.023*
C120.0822 (3)0.53265 (15)1.12077 (11)0.0185 (5)
H12A0.19040.55641.11590.022*
H12B0.07930.47161.15560.022*
C130.0157 (2)0.62660 (15)1.15054 (11)0.0158 (5)
C140.0106 (3)0.71672 (14)1.09252 (11)0.0154 (5)
H140.10050.73511.08590.018*
C150.0832 (3)0.81413 (15)1.13106 (11)0.0191 (5)
H15A0.04570.88281.10980.023*
H15B0.19670.81191.12740.023*
C160.0306 (3)0.80233 (14)1.21114 (11)0.0216 (5)
H16A0.04080.86141.22460.026*
H16B0.12010.80421.24450.026*
C170.0521 (3)0.69056 (14)1.21538 (11)0.0173 (5)
H170.16270.70401.20350.021*
C180.1795 (3)0.58958 (16)1.16724 (12)0.0232 (5)
H18A0.17640.52771.20060.035*
H18B0.23660.64891.19000.035*
H18C0.23060.56831.12180.035*
C190.2043 (2)0.49419 (15)0.91585 (12)0.0199 (5)
H19A0.24880.49240.86610.024*
H19B0.27280.53910.94660.024*
C200.0486 (3)0.64326 (16)1.29112 (11)0.0219 (5)
C210.0887 (3)0.71767 (17)1.35354 (11)0.0293 (6)
H21A0.00350.75691.36910.044*
H21B0.12860.67501.39440.044*
H21C0.16720.76941.33760.044*
C220.0763 (3)0.62330 (17)0.63230 (12)0.0221 (5)
C230.0378 (3)0.60069 (18)0.55382 (12)0.0315 (6)
H23A0.07200.61360.54560.047*
H23B0.09810.64850.52230.047*
H23C0.06220.52520.54240.047*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0238 (9)0.0196 (7)0.0151 (8)0.0004 (7)0.0002 (7)0.0013 (6)
O20.0370 (10)0.0199 (8)0.0232 (9)0.0036 (7)0.0009 (8)0.0023 (7)
O30.0298 (10)0.0191 (7)0.0248 (9)0.0059 (7)0.0058 (8)0.0034 (6)
O40.0604 (13)0.0203 (8)0.0274 (10)0.0038 (9)0.0007 (9)0.0066 (6)
C10.0157 (11)0.0153 (10)0.0200 (11)0.0005 (9)0.0012 (9)0.0014 (8)
C20.0176 (12)0.0158 (10)0.0213 (12)0.0008 (9)0.0014 (10)0.0024 (8)
C30.0208 (12)0.0187 (10)0.0145 (11)0.0006 (10)0.0020 (10)0.0025 (8)
C40.0200 (12)0.0184 (10)0.0180 (11)0.0006 (9)0.0025 (10)0.0005 (9)
C50.0117 (11)0.0207 (11)0.0171 (12)0.0011 (9)0.0000 (9)0.0013 (8)
C60.0175 (12)0.0184 (10)0.0156 (11)0.0014 (9)0.0013 (10)0.0030 (8)
C70.0180 (12)0.0136 (10)0.0199 (11)0.0022 (9)0.0004 (10)0.0003 (8)
C80.0148 (11)0.0144 (10)0.0188 (12)0.0007 (9)0.0010 (10)0.0018 (8)
C90.0179 (12)0.0151 (10)0.0166 (11)0.0003 (9)0.0002 (9)0.0008 (8)
C100.0151 (11)0.0149 (10)0.0185 (11)0.0005 (9)0.0008 (9)0.0007 (8)
C110.0239 (13)0.0165 (10)0.0174 (12)0.0011 (9)0.0008 (9)0.0001 (8)
C120.0221 (12)0.0153 (10)0.0183 (11)0.0025 (9)0.0002 (10)0.0018 (9)
C130.0172 (11)0.0162 (10)0.0139 (11)0.0002 (9)0.0005 (9)0.0022 (8)
C140.0147 (11)0.0138 (10)0.0177 (11)0.0004 (9)0.0003 (9)0.0011 (8)
C150.0226 (12)0.0167 (10)0.0179 (12)0.0032 (9)0.0010 (10)0.0011 (8)
C160.0283 (14)0.0161 (10)0.0204 (12)0.0047 (10)0.0007 (11)0.0028 (8)
C170.0190 (12)0.0162 (10)0.0166 (11)0.0017 (9)0.0023 (10)0.0011 (8)
C180.0236 (13)0.0228 (11)0.0232 (13)0.0034 (10)0.0024 (10)0.0022 (10)
C190.0164 (12)0.0185 (11)0.0250 (12)0.0001 (9)0.0017 (10)0.0007 (9)
C200.0219 (13)0.0230 (11)0.0208 (12)0.0033 (10)0.0033 (11)0.0022 (9)
C210.0440 (17)0.0237 (12)0.0203 (13)0.0065 (11)0.0002 (12)0.0009 (9)
C220.0225 (12)0.0230 (12)0.0208 (12)0.0050 (10)0.0024 (11)0.0019 (9)
C230.0393 (17)0.0329 (12)0.0223 (13)0.0003 (12)0.0019 (12)0.0001 (10)
Geometric parameters (Å, º) top
O1—C221.344 (2)C11—C121.542 (3)
O1—C31.460 (2)C11—H20A0.9900
O2—C221.213 (2)C11—H20B0.9900
O3—C191.435 (2)C12—C131.541 (3)
O3—H3A0.8400C12—H12A0.9900
O4—C201.213 (2)C12—H12B0.9900
C1—C21.538 (3)C13—C181.527 (3)
C1—C101.553 (3)C13—C141.541 (3)
C1—H1A0.9900C13—C171.545 (3)
C1—H1B0.9900C14—C151.533 (3)
C2—C31.508 (3)C14—H141.0000
C2—H2A0.9900C15—C161.545 (3)
C2—H2B0.9900C15—H15A0.9900
C3—C41.519 (3)C15—H15B0.9900
C3—H31.0000C16—C171.561 (3)
C4—C51.513 (3)C16—H16A0.9900
C4—H4A0.9900C16—H16B0.9900
C4—H4B0.9900C17—C201.507 (3)
C5—C61.327 (3)C17—H171.0000
C5—C101.538 (3)C18—H18A0.9800
C6—C71.486 (3)C18—H18B0.9800
C6—H60.9500C18—H18C0.9800
C7—C81.524 (2)C19—H19A0.9900
C7—H7A0.9900C19—H19B0.9900
C7—H7B0.9900C20—C211.509 (3)
C8—C141.514 (3)C21—H21A0.9800
C8—C91.544 (3)C21—H21B0.9800
C8—H81.0000C21—H21C0.9800
C9—C111.547 (3)C22—C231.503 (3)
C9—C101.562 (3)C23—H23A0.9800
C9—H91.0000C23—H23B0.9800
C10—C191.554 (3)C23—H23C0.9800
C22—O1—C3116.09 (15)C11—C12—H12A109.4
C19—O3—H3A109.5C13—C12—H12B109.4
C2—C1—C10115.17 (17)C11—C12—H12B109.4
C2—C1—H1A108.5H12A—C12—H12B108.0
C10—C1—H1A108.5C18—C13—C12111.11 (16)
C2—C1—H1B108.5C18—C13—C14112.45 (17)
C10—C1—H1B108.5C12—C13—C14106.58 (16)
H1A—C1—H1B107.5C18—C13—C17110.81 (18)
C3—C2—C1109.27 (15)C12—C13—C17116.62 (17)
C3—C2—H2A109.8C14—C13—C1798.59 (14)
C1—C2—H2A109.8C8—C14—C15118.33 (17)
C3—C2—H2B109.8C8—C14—C13115.67 (15)
C1—C2—H2B109.8C15—C14—C13103.82 (16)
H2A—C2—H2B108.3C8—C14—H14106.0
O1—C3—C2109.60 (14)C15—C14—H14106.0
O1—C3—C4109.38 (16)C13—C14—H14106.0
C2—C3—C4109.69 (17)C14—C15—C16103.98 (16)
O1—C3—H3109.4C14—C15—H15A111.0
C2—C3—H3109.4C16—C15—H15A111.0
C4—C3—H3109.4C14—C15—H15B111.0
C5—C4—C3110.67 (17)C16—C15—H15B111.0
C5—C4—H4A109.5H15A—C15—H15B109.0
C3—C4—H4A109.5C15—C16—C17105.52 (15)
C5—C4—H4B109.5C15—C16—H16A110.6
C3—C4—H4B109.5C17—C16—H16A110.6
H4A—C4—H4B108.1C15—C16—H16B110.6
C6—C5—C4119.25 (17)C17—C16—H16B110.6
C6—C5—C10123.59 (18)H16A—C16—H16B108.8
C4—C5—C10117.15 (16)C20—C17—C13120.13 (16)
C5—C6—C7125.24 (18)C20—C17—C16112.36 (17)
C5—C6—H6117.4C13—C17—C16103.86 (16)
C7—C6—H6117.4C20—C17—H17106.6
C6—C7—C8112.96 (16)C13—C17—H17106.6
C6—C7—H7A109.0C16—C17—H17106.6
C8—C7—H7A109.0C13—C18—H18A109.5
C6—C7—H7B109.0C13—C18—H18B109.5
C8—C7—H7B109.0H18A—C18—H18B109.5
H7A—C7—H7B107.8C13—C18—H18C109.5
C14—C8—C7109.19 (15)H18A—C18—H18C109.5
C14—C8—C9110.59 (17)H18B—C18—H18C109.5
C7—C8—C9110.59 (16)O3—C19—C10115.04 (17)
C14—C8—H8108.8O3—C19—H19A108.5
C7—C8—H8108.8C10—C19—H19A108.5
C9—C8—H8108.8O3—C19—H19B108.5
C8—C9—C11111.31 (16)C10—C19—H19B108.5
C8—C9—C10112.25 (16)H19A—C19—H19B107.5
C11—C9—C10114.42 (15)O4—C20—C17122.86 (19)
C8—C9—H9106.1O4—C20—C21119.94 (19)
C11—C9—H9106.1C17—C20—C21117.18 (17)
C10—C9—H9106.1C20—C21—H21A109.5
C5—C10—C1108.10 (16)C20—C21—H21B109.5
C5—C10—C19107.29 (16)H21A—C21—H21B109.5
C1—C10—C19110.20 (15)C20—C21—H21C109.5
C5—C10—C9108.97 (15)H21A—C21—H21C109.5
C1—C10—C9109.34 (17)H21B—C21—H21C109.5
C19—C10—C9112.81 (17)O2—C22—O1123.6 (2)
C12—C11—C9113.28 (15)O2—C22—C23124.6 (2)
C12—C11—H20A108.9O1—C22—C23111.88 (18)
C9—C11—H20A108.9C22—C23—H23A109.5
C12—C11—H20B108.9C22—C23—H23B109.5
C9—C11—H20B108.9H23A—C23—H23B109.5
H20A—C11—H20B107.7C22—C23—H23C109.5
C13—C12—C11111.00 (17)H23A—C23—H23C109.5
C13—C12—H12A109.4H23B—C23—H23C109.5
C10—C1—C2—C357.1 (2)C9—C11—C12—C1356.8 (2)
C22—O1—C3—C2162.62 (17)C11—C12—C13—C1865.7 (2)
C22—O1—C3—C477.1 (2)C11—C12—C13—C1457.1 (2)
C1—C2—C3—O1178.82 (16)C11—C12—C13—C17166.01 (16)
C1—C2—C3—C461.1 (2)C7—C8—C14—C1558.5 (2)
O1—C3—C4—C5179.18 (15)C9—C8—C14—C15179.59 (17)
C2—C3—C4—C558.9 (2)C7—C8—C14—C13177.42 (17)
C3—C4—C5—C6126.4 (2)C9—C8—C14—C1355.5 (2)
C3—C4—C5—C1052.6 (2)C18—C13—C14—C863.1 (2)
C4—C5—C6—C7178.7 (2)C12—C13—C14—C858.9 (2)
C10—C5—C6—C72.3 (4)C17—C13—C14—C8179.88 (18)
C5—C6—C7—C810.9 (3)C18—C13—C14—C1568.3 (2)
C6—C7—C8—C14162.88 (18)C12—C13—C14—C15169.74 (17)
C6—C7—C8—C941.0 (3)C17—C13—C14—C1548.5 (2)
C14—C8—C9—C1148.9 (2)C8—C14—C15—C16164.60 (18)
C7—C8—C9—C11169.97 (18)C13—C14—C15—C1634.9 (2)
C14—C8—C9—C10178.62 (16)C14—C15—C16—C176.9 (2)
C7—C8—C9—C1060.3 (2)C18—C13—C17—C2051.9 (2)
C6—C5—C10—C1134.0 (2)C12—C13—C17—C2076.5 (2)
C4—C5—C10—C145.0 (2)C14—C13—C17—C20169.98 (19)
C6—C5—C10—C19107.2 (2)C18—C13—C17—C1674.70 (19)
C4—C5—C10—C1973.8 (2)C12—C13—C17—C16156.87 (17)
C6—C5—C10—C915.2 (3)C14—C13—C17—C1643.38 (19)
C4—C5—C10—C9163.72 (18)C15—C16—C17—C20154.51 (18)
C2—C1—C10—C546.9 (2)C15—C16—C17—C1323.2 (2)
C2—C1—C10—C1970.0 (2)C5—C10—C19—O3165.71 (16)
C2—C1—C10—C9165.42 (16)C1—C10—C19—O348.2 (2)
C8—C9—C10—C545.7 (2)C9—C10—C19—O374.3 (2)
C11—C9—C10—C5173.76 (17)C13—C17—C20—O412.8 (3)
C8—C9—C10—C1163.62 (15)C16—C17—C20—O4135.4 (2)
C11—C9—C10—C168.3 (2)C13—C17—C20—C21168.8 (2)
C8—C9—C10—C1973.38 (19)C16—C17—C20—C2146.2 (3)
C11—C9—C10—C1954.7 (2)C3—O1—C22—O25.2 (3)
C8—C9—C11—C1251.4 (2)C3—O1—C22—C23174.20 (17)
C10—C9—C11—C12179.96 (18)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···O2i0.842.192.9305 (19)147
Symmetry code: (i) x, y1/2, z+3/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···O2i0.842.192.9305 (19)147
Symmetry code: (i) x, y1/2, z+3/2.
references
References top

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