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ISSN: 2056-9890

Crystal structure of bis­­[3-meth­­oxy-17β-estra-1,3,5(10)-trien-17-yl] oxalate

aDepartment of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, Scotland
*Correspondence e-mail: w.harrison@abdn.ac.uk

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 1 April 2014; accepted 24 April 2014; online 19 July 2014)

In the title compound, C40H50O6, a symmetrical steroid oxalate diester, the dihedral angle between the CO2 planes of the oxalate linker is 61.5 (5)° and the C—C bond length is 1.513 (6) Å. The steroid B, C and D rings adopt half-chair, chair and envelope conformations, respectively, in both halves of the mol­ecule, which adopts an overall shallow V-shaped conformation. In the crystal, mol­ecules are linked by weak C—H⋯O inter­actions, forming a three-dimensional network.

1. Chemical context

The pyrolysis of esters possessing aliphatic β-hydrogen atoms is a known route to alkenes via radical mediated β-elimination (Brown, 1980[Brown, R. F. C. (1980). Pyrolytic Methods in Organic Chemistry, pp. 85-89. New York: Academic Press.]). As part of our studies in this area (Nahar, 2007[Nahar, L. (2007). PhD thesis, University of Aberdeen, Scotland.]), we now describe the crystal structure of the title compound, (I)[link], an oxalate diester of 17-β-estradiol 3-methyl ether (Reck et al., 1986[Reck, G., Schubert, G. & Bannier, G. (1986). Cryst. Res. Technol. 21, 1313-1319.]; Schönnecker et al., 2000[Schönnecker, B., Lange, C., Kötteritzsch, M., Günther, W., Weston, J., Anders, E. & Görls, H. (2000). J. Org. Chem. 65, 5487-5497.]). Flash-vacuum pyrolysis (FVP) of (I)[link] at 873 K and 0.2 torr led to estra­tetra­ene 3-methyl ether in 47% yield.

[Scheme 1]

2. Structural commentary

The atom labelling scheme (Fig. 1[link]) for (I)[link] relates equivalent atoms in the two halves of the mol­ecule by adding 50, e.g. C1 and C51. The C19—C69 bond length of 1.513 (6) Å for the oxalate unit is exactly as expected for an sp2sp2 carbon–carbon single bond but significantly shorter than the typical C—C bond length of about 1.57 Å in isolated oxalate ions (Dinnebier et al., 2003[Dinnebier, R. E., Vensky, S., Panthöfer, M. & Jansen, M. (2003). Inorg. Chem. 42, 1499-1507.]). The mean C—OC bond length is 1.324 Å and the mean C=O bond length is 1.197 Å. The dihedral angle between the C19/O1/O2 and C69/O51/O52 planes of 61.5 (5)° indicates a substantial twist. This leads to an overall shallow V-shaped conformation for the mol­ecule, with the C18 and C68 methyl groups facing each other [C18⋯C68 = 4.64 Å]. This could be significant in terms of the radical-reactivity of this mol­ecule under FVP (Nahar, 2007[Nahar, L. (2007). PhD thesis, University of Aberdeen, Scotland.]).

[Figure 1]
Figure 1
A view of the mol­ecular structure of the title mol­ecule, with atom labelling. Displacement ellipsoids are drawn at the 50% probability level. All the H atoms except those bonded to the chiral C atoms have been omitted for clarity.

The meth­oxy carbon atom C3A is displaced from the C1–C5/C10 ring plane by −0.114 (7) Å. The C5–C10 ring conformation approximates to a half-chair with C7 and C8 displaced from the C5/C6/C9/C10 plane by 0.287 (7) and −0.477 (7) Å, respectively. The C8/C9/C11–C14 ring is a normal chair. The C13–C17 five-membered ring is an envelope, with C13 displaced from the mean plane of the other four C atoms by −0.735 (6) Å.

These ring conformations are essentially duplicated in the second half of the mol­ecule: C53A is displaced from the C51–C55/C60 plane by 0.096 (7) Å. For the C55–C60 ring, atoms C57 and C58 are displaced from the C55/C56/C59/C60 plane by −0.340 (7) and 0.422 (7) Å, respectively. The C58/C59/C61–C64 ring is a normal chair. The C63–C67 ring is an envelope, with C63 displaced from the mean plane of the other four atoms by 0.735 (6) Å.

The stereogenic centres in (I)[link] have the following assumed chiralities: C8 R, C9 S, C13 S, C14 S, C17 S, C58 R, C59 S, C63 S, C64 S, C67 S to match the known absolute structure of the starting steroid (Reck et al., 1986[Reck, G., Schubert, G. & Bannier, G. (1986). Cryst. Res. Technol. 21, 1313-1319.]).

3. Supra­molecular features

In the crystal, mol­ecules are linked by weak C—H⋯O inter­actions (Table 1[link]). Inter­estingly, these three bonds all arise from one `end' of the mol­ecule. Two of these bonds are accepted by the same oxalate O atom and a three-dimensional network arises (Fig. 2[link]).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C52—H52⋯O2i 0.95 2.51 3.161 (5) 126
C53A—H53B⋯O53ii 0.98 2.51 3.378 (6) 147
C54—H54⋯O2iii 0.95 2.56 3.309 (5) 136
Symmetry codes: (i) [-x+1, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]; (ii) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1]; (iii) [-x, y+{\script{1\over 2}}, -z+{\script{3\over 2}}].
[Figure 2]
Figure 2
The packing in (I)[link] viewed down [100] with C—H⋯O hydrogen bonds indicated by yellow lines. All H atoms not involved in such inter­actions have been omitted for clarity.

4. Database survey

In the closely related de­hydro­epiandrosterone oxalate diester (Cox et al., 2007[Cox, P. J., Nahar, L., Sarker, S. D. & Turner, A. B. (2007). Acta Cryst. E63, o3222.]), the dihedral angles between the CO2 planes of the oxalate linkers in the two asymmetric mol­ecules are 24.2 (3) and 51.46 (11)°.

A search of the Cambridge Structural Database (Version 5.31; Allen & Motherwell, 2002[Allen, F. H. & Motherwell, W. D. S. (2002). Acta Cryst. B58, 407-422.]) revealed four other structures containing an oxalate diester bridge between two fragments connected to the bridge by a secondary carbon atom. In C22H34O4 polymorph-I (Barnes & Weakley, 2004a[Barnes, J. C. & Weakley, T. J. R. (2004a). Private communication (refcode FOGGUE). CCDC, Cambridge, England.]) the dihedral angle between the CO2 groups in the oxalate fragment is 12.5 (9)° and the bornyl substituents adopt a syn orientation. C22H34O4 polymorph-II (Barnes & Weakley, 2004b[Barnes, J. C. & Weakley, T. J. R. (2004b). Private communication (refcode LAKGIO). CCDC, Cambridge, England.]) contains one-and-a-half mol­ecules in the asymmetric unit, with the half-mol­ecule completed by inversion symmetry, hence the oxalate bridge is planar by symmetry; in the complete mol­ecule, the oxalate dihedral angle is 12.2 (5)°. In both mol­ecules, the bornyl substituents are in an anti orientation.

In bis­(cis-(+)-2-(4-meth­oxy­phen­yl)-4-oxo-2,3,4,5-tetra­hydro-1,5-benzo­thia­zepin-3-yl) oxalate monohydrate (C34H28N2O8S2·H2O; Kumaradhas et al., 2008[Kumaradhas, P., Stephen, A. D., Nirmala, K. A. & Kalyanam, N. (2008). X-Ray Struct. Anal. Online, 24, x113-x114.]), the oxalate dihedral angle is 27.2 (5)° with the substituents in an anti disposition. Finally, in bis­(di-t-butyl­meth­yl)oxalate (C20H38O4; Adiwidjaja & Voss, 1976[Adiwidjaja, G. & Voss, J. (1976). Chem. Ber. 109, 761-768.]), the oxalate unit is close to planar [dihedral angle = 5.6 (2)°], but the bulky substituents lie in a syn orientation.

5. Synthesis and crystallization

The title compound was prepared by the method of Lotowski & Guzmanski (2005[Lotowski, L. & Guzmanski, D. (2005). Monatsh. Chem. 136, 153-158.]) and recrystallized from di­chloro­methane/pyridine solution as colourless rods. M.p. 534–535 K; selected 1H NMR δ 0.86 (s, 18-Me), 3.74 (s, OMe), 4.79 (m, 17αH), 6.59 (d, 4-H), 6.67 (dd, 2-H), 7.16 (d, 1-H), 13C NMR δ 12.0, 23.3, 26.2, 27.2, 27.3, 29.7, 36.8, 38.5, 43.3, 43.7, 49.7, 55.2, 85.3, 111.5, 113.8, 126.3,132.3, 137,8, 157.5, 158.2.

6. Refinement

The crystal quality was only fair, which may correlate with the rather high Rint value. The H atoms were placed in calculated positions (C—H = 0.95–0.99 Å) and refined as riding atoms with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C). The methyl groups were allowed to rotate, but not to tip, to best fit the electron density. Experimental details are given in Table 2[link].

Table 2
Experimental details

Crystal data
Chemical formula C40H50O6
Mr 626.80
Crystal system, space group Orthorhombic, P212121
Temperature (K) 120
a, b, c (Å) 7.8559 (4), 14.1579 (10), 29.888 (2)
V3) 3324.2 (4)
Z 4
Radiation type Mo Kα
μ (mm−1) 0.08
Crystal size (mm) 0.25 × 0.08 × 0.06
 
Data collection
Diffractometer Nonius KappaCCD
No. of measured, independent and observed [I > 2σ(I)] reflections 21809, 3674, 2220
Rint 0.169
(sin θ/λ)max−1) 0.617
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.075, 0.128, 1.02
No. of reflections 3674
No. of parameters 420
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.32, −0.31
Computer programs: COLLECT (Nonius, 1998[Nonius (1998). COLLECT. Nonius BV, Delft, The Netherlands.]), DENZO and SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter, Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]), SORTAV (Blessing, 1995[Blessing, R. H. (1995). Acta Cryst. A51, 33-38.]), SHELXS97 and SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information


Chemical context top

The pyrolysis of esters possessing aliphatic β-hydrogen atoms is a known route to alkenes via radical mediated β-elimination (Brown, 1980). As part of our studies in this area (Nahar, 2007), we now describe the crystal structure of the title compound, (I), an oxalate diester of 17-β-estradiol 3-methyl ether (Reck et al., 1986; Schönnecker et al., 2000). Flash-vacuum pyrolysis (FVP) of the (I) at 873 K and 0.2 torr led to estra­tetra­ene 3-methyl ether in 47% yield.

Structural commentary top

The atom labelling scheme (Fig. 1) for (I) relates equivalent atoms in the two halves of the molecule by adding 50, e.g. C1 and C51. The C19—C69 bond length of 1.513 (6) Å for the oxalate unit is exactly as expected for an sp2sp2 carbon–carbon single bond but significantly shorter than the typical C—C bond length of about 1.57 Å in isolated oxalate ions (Dinnebier et al., 2003). The mean C—OC bond length is 1.324 Å and the mean CO bond length is 1.197 Å. The dihedral angle between the C19/O1/O2 and C69/O51/O52 planes of 61.5 (5)° indicates a substantial twist. This leads to an overall shallow V-shaped conformation for the molecule, with the C18 and C68 methyl groups facing each other [C18···C68 = 4.64 Å]. This could be significant in terms of the radical-reactivity of this molecule under FVP (Nahar, 2007).

The meth­oxy carbon atom C3A is displaced from the C1–C5/C10 ring plane by -0.114 (7) Å. The C5–C10 ring conformation approximates to a half-chair with C7 and C8 displaced from the C5/C6/C9/C10 plane by 0.287 (7) and -0.477 (7) Å, respectively. The C8/C9/C11–C14 ring is a normal chair. The C13–C17 five-membered ring is an envelope, with C13 displaced from the mean plane of the other four C atoms by -0.735 (6) Å.

These ring conformations are essentially duplicated in the second half of the molecule: C53A is displaced from the C51–C55/C60 plane by 0.096 (7) Å. For the C55–C60 ring, atoms C57 and C58 are displaced from the C55/C56/C59/C60 plane by -0.340 (7) and 0.422 (7) Å, respectively. The C58/C59/C61–C64 ring is a normal chair. The C63–C67 ring is an envelope, with C63 displaced from the mean plane of the other four atoms by 0.735 (6) Å.

The stereogenic centres in (I) have the following assumed chiralities: C8 R, C9 S, C13 S, C14 S, C17 S, C58 R, C59 S, C63 S, C64 S, C67 S to match the known absolute structure of the starting steroid (Reck et al., 1986).

Supra­molecular features top

In the crystal, molecules are linked by weak C—H···O inter­actions (Table 2). Inter­estingly, these three bonds all arise from one `end' of the molecule. Two of these bonds are accepted by the same oxalate O atom and a three-dimensional network arises.

Database survey top

In the closely related de­hydro­epiandrosterone oxalate diester (Cox et al., 2007), the dihedral angles between the CO2 planes of the oxalate linkers in the two asymmetric molecules are 24.2 (3) and 51.46 (11)°.

A search of the Cambridge Structural Database (version 5.31; Allen & Motherwell, 2002) revealed four other structures containing an oxalate diester bridge between two fragments connected to the bridge by a secondary carbon atom. In C22H34O4 polymorph-I (Barnes & Weakley, 2004a) the dihedral angle between the CO2 groups in the oxalate fragment is 12.5 (9)° and the bornyl substituents adopt a syn orientation. C22H34O4 polymorph-II (Barnes & Weakley, 2004b) contains one-and-a-half molecules in the asymmetric unit, with the half-molecule completed by inversion symmetry, hence the oxalate bridge is planar by symmetry; in the complete molecule, the oxalate dihedral angle is 12.2 (5)°. In both molecules, the bornyl substituents are in an anti orientation.

In bis­(cis-(+)-2-(4-meth­oxy­phenyl)-4-oxo-2,3,4,5-tetra­hydro-1,5-benzo­thia­zepin-3-yl) oxalate monohydrate (C34H28N2O8S2.H2O; Kumaradhas et al., 2008), the oxalate dihedral angle is 27.2 (5)° with the substituents in an anti disposition. Finally, in bis­(di-t-butyl­methyl)­oxalate (C20H38O4; Adiwidjaja & Voss, 1976), the oxalate unit is close to planar [dihedral angle = 5.6 (2)°], but the bulky substituents lie in a syn orientation.

Synthesis and crystallization top

The title compound was prepared by the method of Lotowski & Guzmanski (2005) and recrystallized from di­chloro­methane/pyridine solution as colourless rods. M.p. 534–535 K; selected 1H NMR δ 0.86 (s, 18-Me), 3.74 (s, OMe), 4.79 (m, 17αH), 6.59 (d, 4-H), 6.67 (dd, 2-H), 7.16 (d, 1-H), 13C NMR δ 12.0, 23.3, 26.2, 27.2, 27.3, 29.7, 36.8, 38.5, 43.3, 43.7, 49.7, 55.2, 85.3, 111.5, 113.8, 126.3,132.3, 137,8, 157.5, 158.2.

Refinement top

The crystal quality was only fair, which may correlate with the rather high Rint value. The H atoms were placed in calculated positions (C—H = 0.95–0.99 Å) and refined as riding atoms with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C). The methyl groups were allowed to rotate, but not to tip, to best fit the electron density.

Related literature top

For related literature, see: Adiwidjaja & Voss (1976); Allen & Motherwell (2002); Barnes & Weakley (2004a, 2004b); Brown (1980); Cox et al. (2007); Dinnebier et al. (2003); Kumaradhas et al. (2008); Lotowski & Guzmanski (2005); Nahar (2007); Reck et al. (1986); Schönnecker et al. (2000).

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997), and SORTAV (Blessing, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A view of the molecular structure of the title molecule, with atom labelling. Displacement ellipsoids are drawn at the 50% probability level. All the H atoms except those bonded to the chiral C atoms have been omitted for clarity.
[Figure 2] Fig. 2. The packing in (I) viewed down [100] with C—H···O hydrogen bonds indicated by yellow lines. All H atoms not involved in such interactions have been omitted for clarity.
Bis[3-methoxy-17β-estra-1,3,5(10)-trien-17-yl] oxalate top
Crystal data top
C40H50O6F(000) = 1352
Mr = 626.80Dx = 1.252 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 4069 reflections
a = 7.8559 (4) Åθ = 1.0–27.5°
b = 14.1579 (10) ŵ = 0.08 mm1
c = 29.888 (2) ÅT = 120 K
V = 3324.2 (4) Å3Rod, colourless
Z = 40.25 × 0.08 × 0.06 mm
Data collection top
Nonius KappaCCD
diffractometer
2220 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.169
Graphite monochromatorθmax = 26.0°, θmin = 2.9°
ω and ϕ scansh = 98
21809 measured reflectionsk = 1717
3674 independent reflectionsl = 3536
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.075H-atom parameters constrained
wR(F2) = 0.128 w = 1/[σ2(Fo2) + (0.0633P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max < 0.001
3674 reflectionsΔρmax = 0.32 e Å3
420 parametersΔρmin = 0.31 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0132 (14)
Crystal data top
C40H50O6V = 3324.2 (4) Å3
Mr = 626.80Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 7.8559 (4) ŵ = 0.08 mm1
b = 14.1579 (10) ÅT = 120 K
c = 29.888 (2) Å0.25 × 0.08 × 0.06 mm
Data collection top
Nonius KappaCCD
diffractometer
2220 reflections with I > 2σ(I)
21809 measured reflectionsRint = 0.169
3674 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0750 restraints
wR(F2) = 0.128H-atom parameters constrained
S = 1.02Δρmax = 0.32 e Å3
3674 reflectionsΔρmin = 0.31 e Å3
420 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
C10.1936 (5)0.1231 (3)1.09702 (12)0.0288 (10)
H10.12440.07721.08260.035*
C20.1253 (6)0.1738 (3)1.13226 (13)0.0320 (11)
H20.01080.16391.14130.038*
C30.2256 (6)0.2390 (3)1.15401 (13)0.0317 (11)
C3A0.0043 (6)0.2884 (3)1.20355 (15)0.0525 (14)
H3A0.01510.33221.22850.079*
H3B0.02280.22401.21310.079*
H3C0.06870.30601.17830.079*
C40.3910 (6)0.2540 (3)1.13966 (13)0.0308 (11)
H40.46000.29911.15470.037*
C50.4578 (5)0.2042 (3)1.10366 (12)0.0283 (10)
C60.6359 (5)0.2281 (3)1.08821 (13)0.0316 (11)
H6A0.70950.23641.11480.038*
H6B0.63280.28911.07200.038*
C70.7154 (5)0.1538 (3)1.05784 (12)0.0284 (10)
H7A0.81830.18021.04340.034*
H7B0.75030.09851.07590.034*
C80.5891 (5)0.1231 (3)1.02223 (12)0.0268 (10)
H80.54790.18031.00590.032*
C90.4351 (5)0.0748 (3)1.04514 (12)0.0275 (10)
H90.48240.01801.06070.033*
C100.3587 (5)0.1362 (3)1.08178 (13)0.0259 (10)
C110.3043 (5)0.0365 (3)1.01134 (13)0.0323 (10)
H11A0.24830.09020.99610.039*
H11B0.21570.00061.02760.039*
C120.3877 (5)0.0279 (3)0.97611 (13)0.0315 (11)
H12A0.42840.08650.99080.038*
H12B0.30190.04580.95340.038*
C130.5359 (6)0.0206 (3)0.95328 (12)0.0276 (10)
C140.6641 (5)0.0544 (3)0.98867 (12)0.0253 (10)
H140.69810.00291.00610.030*
C150.8217 (5)0.0831 (3)0.96073 (13)0.0347 (11)
H15A0.92770.07440.97820.042*
H15B0.81380.14990.95120.042*
C160.8178 (6)0.0159 (3)0.91974 (14)0.0381 (12)
H16A0.81190.05210.89150.046*
H16B0.92000.02500.91910.046*
C170.6567 (6)0.0427 (3)0.92658 (12)0.0313 (11)
H170.68480.10010.94470.038*
C180.4706 (6)0.1014 (3)0.92326 (13)0.0335 (11)
H18A0.56710.13140.90810.050*
H18B0.41140.14830.94170.050*
H18C0.39180.07580.90090.050*
C510.1276 (5)0.1300 (3)0.61705 (12)0.0272 (10)
H510.24520.12500.62410.033*
C520.0804 (5)0.1861 (3)0.58125 (13)0.0276 (10)
H520.16350.21930.56430.033*
C530.0910 (6)0.1929 (3)0.57065 (13)0.0292 (10)
C53A0.0362 (6)0.3019 (3)0.51109 (13)0.0377 (11)
H53A0.09580.33380.48660.057*
H53B0.05420.26180.49880.057*
H53C0.01370.34910.53110.057*
C540.2088 (6)0.1447 (3)0.59550 (13)0.0323 (10)
H540.32580.14940.58780.039*
C550.1614 (5)0.0891 (3)0.63183 (13)0.0283 (10)
C560.2988 (5)0.0420 (3)0.65920 (14)0.0340 (11)
H56A0.38690.01690.63870.041*
H56B0.35360.09000.67850.041*
C570.2337 (5)0.0382 (3)0.68852 (14)0.0332 (11)
H57A0.32330.05710.71010.040*
H57B0.20640.09370.66960.040*
C580.0757 (5)0.0071 (3)0.71376 (13)0.0287 (10)
H580.10300.05190.73070.034*
C590.0704 (5)0.0145 (3)0.68065 (12)0.0269 (10)
H590.09820.04690.66580.032*
C600.0123 (5)0.0806 (3)0.64322 (12)0.0248 (10)
C610.2325 (5)0.0455 (3)0.70446 (12)0.0304 (10)
H61A0.21230.10680.71950.037*
H61B0.32410.05460.68210.037*
C620.2897 (6)0.0270 (3)0.73903 (13)0.0328 (10)
H62A0.32480.08560.72350.039*
H62B0.38980.00220.75530.039*
C630.1492 (5)0.0500 (3)0.77237 (12)0.0286 (10)
C640.0115 (5)0.0810 (3)0.74658 (13)0.0303 (10)
H640.02390.13630.72800.036*
C650.1299 (6)0.1210 (3)0.78286 (13)0.0441 (13)
H65A0.20750.16940.77030.053*
H65B0.19840.07030.79690.053*
C660.0042 (6)0.1654 (3)0.81707 (16)0.0505 (14)
H66A0.02240.13860.84730.061*
H66B0.01910.23470.81850.061*
C670.1733 (6)0.1400 (3)0.79949 (13)0.0376 (12)
H670.21570.19170.77950.045*
C680.1171 (6)0.0345 (3)0.80322 (13)0.0346 (11)
H68A0.09370.09080.78510.052*
H68B0.21800.04570.82180.052*
H68C0.01910.02120.82250.052*
C190.5300 (5)0.1607 (3)0.88064 (14)0.0311 (11)
C690.4324 (6)0.1782 (3)0.83780 (14)0.0327 (11)
O10.5808 (4)0.07180 (19)0.88412 (8)0.0351 (8)
O20.5552 (4)0.2225 (2)0.90715 (10)0.0454 (9)
O30.1760 (4)0.2930 (2)1.19035 (9)0.0447 (9)
O510.2916 (4)0.12707 (19)0.83696 (9)0.0375 (8)
O520.4778 (4)0.2347 (2)0.81047 (10)0.0546 (10)
O530.1536 (4)0.2451 (2)0.53540 (9)0.0406 (8)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.032 (3)0.026 (2)0.028 (2)0.003 (2)0.003 (2)0.0007 (18)
C20.030 (3)0.035 (2)0.031 (2)0.000 (2)0.002 (2)0.005 (2)
C30.046 (3)0.026 (2)0.023 (2)0.009 (2)0.001 (2)0.0015 (18)
C3A0.061 (4)0.051 (3)0.046 (3)0.017 (3)0.004 (3)0.003 (2)
C40.037 (3)0.023 (2)0.032 (2)0.002 (2)0.004 (2)0.0001 (19)
C50.034 (3)0.022 (2)0.029 (2)0.001 (2)0.003 (2)0.0044 (18)
C60.032 (3)0.031 (3)0.032 (2)0.008 (2)0.004 (2)0.0015 (19)
C70.024 (3)0.028 (2)0.033 (2)0.004 (2)0.001 (2)0.0029 (18)
C80.026 (3)0.027 (2)0.027 (2)0.004 (2)0.0035 (19)0.0018 (18)
C90.033 (3)0.023 (2)0.027 (2)0.003 (2)0.001 (2)0.0030 (17)
C100.029 (3)0.022 (2)0.026 (2)0.002 (2)0.003 (2)0.0055 (18)
C110.031 (3)0.037 (2)0.028 (2)0.011 (2)0.000 (2)0.0013 (19)
C120.039 (3)0.027 (2)0.028 (2)0.008 (2)0.003 (2)0.0022 (18)
C130.037 (3)0.022 (2)0.025 (2)0.002 (2)0.002 (2)0.0045 (17)
C140.024 (3)0.027 (2)0.025 (2)0.0007 (19)0.0010 (19)0.0077 (17)
C150.025 (3)0.041 (3)0.037 (2)0.005 (2)0.005 (2)0.003 (2)
C160.040 (3)0.040 (3)0.035 (2)0.005 (2)0.006 (2)0.003 (2)
C170.042 (3)0.032 (2)0.020 (2)0.006 (2)0.003 (2)0.0003 (18)
C180.037 (3)0.034 (3)0.029 (2)0.005 (2)0.001 (2)0.0014 (19)
C510.023 (2)0.032 (2)0.026 (2)0.001 (2)0.001 (2)0.0046 (19)
C520.025 (3)0.032 (2)0.026 (2)0.001 (2)0.003 (2)0.0046 (19)
C530.030 (3)0.029 (2)0.029 (2)0.005 (2)0.003 (2)0.0032 (19)
C53A0.041 (3)0.036 (3)0.035 (2)0.001 (2)0.004 (2)0.001 (2)
C540.024 (3)0.040 (3)0.033 (2)0.001 (2)0.000 (2)0.002 (2)
C550.025 (3)0.029 (2)0.031 (2)0.002 (2)0.004 (2)0.0032 (18)
C560.026 (3)0.038 (3)0.038 (2)0.004 (2)0.003 (2)0.004 (2)
C570.026 (3)0.037 (3)0.037 (2)0.006 (2)0.000 (2)0.000 (2)
C580.028 (3)0.028 (2)0.030 (2)0.001 (2)0.005 (2)0.0043 (18)
C590.028 (3)0.029 (2)0.024 (2)0.001 (2)0.0016 (19)0.0042 (17)
C600.022 (3)0.024 (2)0.028 (2)0.000 (2)0.003 (2)0.0050 (18)
C610.025 (3)0.043 (3)0.024 (2)0.001 (2)0.003 (2)0.0011 (19)
C620.031 (3)0.040 (3)0.027 (2)0.004 (2)0.002 (2)0.0039 (19)
C630.031 (3)0.026 (2)0.028 (2)0.001 (2)0.001 (2)0.0004 (18)
C640.031 (3)0.029 (2)0.031 (2)0.001 (2)0.001 (2)0.0008 (18)
C650.047 (3)0.048 (3)0.037 (3)0.015 (2)0.003 (2)0.013 (2)
C660.057 (4)0.049 (3)0.046 (3)0.021 (3)0.011 (3)0.012 (2)
C670.046 (3)0.037 (3)0.030 (2)0.000 (2)0.009 (2)0.001 (2)
C680.035 (3)0.035 (3)0.033 (2)0.001 (2)0.001 (2)0.0058 (19)
C190.028 (3)0.031 (3)0.034 (2)0.004 (2)0.006 (2)0.001 (2)
C690.039 (3)0.026 (2)0.034 (2)0.000 (2)0.005 (2)0.002 (2)
O10.052 (2)0.0255 (16)0.0274 (15)0.0023 (15)0.0004 (15)0.0002 (12)
O20.045 (2)0.0339 (19)0.058 (2)0.0012 (16)0.0153 (18)0.0103 (16)
O30.047 (2)0.046 (2)0.0405 (18)0.0055 (17)0.0089 (17)0.0084 (15)
O510.046 (2)0.0330 (17)0.0334 (16)0.0086 (17)0.0078 (16)0.0033 (14)
O520.048 (2)0.062 (2)0.054 (2)0.0107 (19)0.0021 (18)0.0253 (18)
O530.0330 (19)0.0466 (19)0.0421 (17)0.0020 (15)0.0014 (16)0.0135 (15)
Geometric parameters (Å, º) top
C1—C21.383 (5)C52—C531.387 (6)
C1—C101.387 (5)C52—H520.9500
C1—H10.9500C53—C541.369 (5)
C2—C31.376 (6)C53—O531.378 (4)
C2—H20.9500C53A—O531.423 (5)
C3—O31.384 (5)C53A—H53A0.9800
C3—C41.385 (6)C53A—H53B0.9800
C3A—O31.407 (5)C53A—H53C0.9800
C3A—H3A0.9800C54—C551.392 (5)
C3A—H3B0.9800C54—H540.9500
C3A—H3C0.9800C55—C601.412 (5)
C4—C51.390 (5)C55—C561.509 (6)
C4—H40.9500C56—C571.523 (5)
C5—C101.400 (5)C56—H56A0.9900
C5—C61.512 (6)C56—H56B0.9900
C6—C71.523 (5)C57—C581.518 (5)
C6—H6A0.9900C57—H57A0.9900
C6—H6B0.9900C57—H57B0.9900
C7—C81.519 (5)C58—C641.521 (5)
C7—H7A0.9900C58—C591.546 (6)
C7—H7B0.9900C58—H581.0000
C8—C141.516 (5)C59—C611.524 (5)
C8—C91.549 (5)C59—C601.528 (5)
C8—H81.0000C59—H591.0000
C9—C101.523 (5)C61—C621.524 (5)
C9—C111.539 (5)C61—H61A0.9900
C9—H91.0000C61—H61B0.9900
C11—C121.540 (5)C62—C631.522 (5)
C11—H11A0.9900C62—H62A0.9900
C11—H11B0.9900C62—H62B0.9900
C12—C131.514 (5)C63—C671.523 (5)
C12—H12A0.9900C63—C681.531 (5)
C12—H12B0.9900C63—C641.544 (6)
C13—C171.530 (5)C64—C651.537 (6)
C13—C141.537 (5)C64—H641.0000
C13—C181.542 (5)C65—C661.554 (6)
C14—C151.547 (5)C65—H65A0.9900
C14—H141.0000C65—H65B0.9900
C15—C161.552 (5)C66—C671.533 (6)
C15—H15A0.9900C66—H66A0.9900
C15—H15B0.9900C66—H66B0.9900
C16—C171.527 (6)C67—O511.467 (5)
C16—H16A0.9900C67—H671.0000
C16—H16B0.9900C68—H68A0.9800
C17—O11.461 (4)C68—H68B0.9800
C17—H171.0000C68—H68C0.9800
C18—H18A0.9800C19—O21.197 (5)
C18—H18B0.9800C19—O11.325 (5)
C18—H18C0.9800C19—C691.513 (6)
C51—C521.383 (5)C69—O521.198 (5)
C51—C601.386 (5)C69—O511.322 (5)
C51—H510.9500
C2—C1—C10122.9 (4)C53—C52—H52120.8
C2—C1—H1118.6C54—C53—O53116.2 (4)
C10—C1—H1118.6C54—C53—C52119.9 (4)
C3—C2—C1119.1 (4)O53—C53—C52123.9 (4)
C3—C2—H2120.5O53—C53A—H53A109.5
C1—C2—H2120.5O53—C53A—H53B109.5
C2—C3—O3125.5 (4)H53A—C53A—H53B109.5
C2—C3—C4119.6 (4)O53—C53A—H53C109.5
O3—C3—C4115.0 (4)H53A—C53A—H53C109.5
O3—C3A—H3A109.5H53B—C53A—H53C109.5
O3—C3A—H3B109.5C53—C54—C55121.6 (4)
H3A—C3A—H3B109.5C53—C54—H54119.2
O3—C3A—H3C109.5C55—C54—H54119.2
H3A—C3A—H3C109.5C54—C55—C60119.6 (4)
H3B—C3A—H3C109.5C54—C55—C56118.8 (4)
C3—C4—C5121.1 (4)C60—C55—C56121.5 (4)
C3—C4—H4119.5C55—C56—C57113.6 (3)
C5—C4—H4119.5C55—C56—H56A108.8
C4—C5—C10120.1 (4)C57—C56—H56A108.8
C4—C5—C6118.2 (4)C55—C56—H56B108.8
C10—C5—C6121.7 (4)C57—C56—H56B108.8
C5—C6—C7114.0 (3)H56A—C56—H56B107.7
C5—C6—H6A108.7C58—C57—C56110.1 (3)
C7—C6—H6A108.7C58—C57—H57A109.6
C5—C6—H6B108.7C56—C57—H57A109.6
C7—C6—H6B108.7C58—C57—H57B109.6
H6A—C6—H6B107.6C56—C57—H57B109.6
C8—C7—C6110.3 (3)H57A—C57—H57B108.2
C8—C7—H7A109.6C57—C58—C64113.0 (3)
C6—C7—H7A109.6C57—C58—C59110.3 (3)
C8—C7—H7B109.6C64—C58—C59107.6 (3)
C6—C7—H7B109.6C57—C58—H58108.6
H7A—C7—H7B108.1C64—C58—H58108.6
C14—C8—C7113.2 (3)C59—C58—H58108.6
C14—C8—C9108.2 (3)C61—C59—C60114.5 (3)
C7—C8—C9109.1 (3)C61—C59—C58112.2 (3)
C14—C8—H8108.8C60—C59—C58111.6 (3)
C7—C8—H8108.8C61—C59—H59105.9
C9—C8—H8108.8C60—C59—H59105.9
C10—C9—C11114.2 (3)C58—C59—H59105.9
C10—C9—C8111.9 (3)C51—C60—C55116.9 (4)
C11—C9—C8112.7 (3)C51—C60—C59121.8 (4)
C10—C9—H9105.7C55—C60—C59121.1 (4)
C11—C9—H9105.7C59—C61—C62111.7 (3)
C8—C9—H9105.7C59—C61—H61A109.3
C1—C10—C5117.3 (4)C62—C61—H61A109.3
C1—C10—C9121.9 (4)C59—C61—H61B109.3
C5—C10—C9120.6 (4)C62—C61—H61B109.3
C9—C11—C12111.9 (3)H61A—C61—H61B107.9
C9—C11—H11A109.2C63—C62—C61111.9 (3)
C12—C11—H11A109.2C63—C62—H62A109.2
C9—C11—H11B109.2C61—C62—H62A109.2
C12—C11—H11B109.2C63—C62—H62B109.2
H11A—C11—H11B107.9C61—C62—H62B109.2
C13—C12—C11111.5 (3)H62A—C62—H62B107.9
C13—C12—H12A109.3C62—C63—C67115.9 (3)
C11—C12—H12A109.3C62—C63—C68110.3 (3)
C13—C12—H12B109.3C67—C63—C68110.8 (3)
C11—C12—H12B109.3C62—C63—C64109.1 (3)
H12A—C12—H12B108.0C67—C63—C6497.4 (3)
C12—C13—C17116.5 (3)C68—C63—C64112.9 (3)
C12—C13—C14109.6 (3)C58—C64—C65120.5 (4)
C17—C13—C1497.8 (3)C58—C64—C63113.4 (3)
C12—C13—C18110.1 (4)C65—C64—C63104.3 (3)
C17—C13—C18109.7 (3)C58—C64—H64105.8
C14—C13—C18112.8 (3)C65—C64—H64105.8
C8—C14—C13113.6 (3)C63—C64—H64105.8
C8—C14—C15120.0 (3)C64—C65—C66103.2 (4)
C13—C14—C15103.6 (3)C64—C65—H65A111.1
C8—C14—H14106.2C66—C65—H65A111.1
C13—C14—H14106.2C64—C65—H65B111.1
C15—C14—H14106.2C66—C65—H65B111.1
C14—C15—C16104.4 (3)H65A—C65—H65B109.1
C14—C15—H15A110.9C67—C66—C65105.0 (3)
C16—C15—H15A110.9C67—C66—H66A110.8
C14—C15—H15B110.9C65—C66—H66A110.8
C16—C15—H15B110.9C67—C66—H66B110.8
H15A—C15—H15B108.9C65—C66—H66B110.8
C17—C16—C15104.1 (3)H66A—C66—H66B108.8
C17—C16—H16A110.9O51—C67—C63112.4 (3)
C15—C16—H16A110.9O51—C67—C66110.1 (3)
C17—C16—H16B110.9C63—C67—C66105.4 (4)
C15—C16—H16B110.9O51—C67—H67109.6
H16A—C16—H16B109.0C63—C67—H67109.6
O1—C17—C16112.0 (3)C66—C67—H67109.6
O1—C17—C13111.4 (3)C63—C68—H68A109.5
C16—C17—C13105.4 (3)C63—C68—H68B109.5
O1—C17—H17109.3H68A—C68—H68B109.5
C16—C17—H17109.3C63—C68—H68C109.5
C13—C17—H17109.3H68A—C68—H68C109.5
C13—C18—H18A109.5H68B—C68—H68C109.5
C13—C18—H18B109.5O2—C19—O1126.4 (4)
H18A—C18—H18B109.5O2—C19—C69121.7 (4)
C13—C18—H18C109.5O1—C19—C69112.0 (3)
H18A—C18—H18C109.5O52—C69—O51127.0 (4)
H18B—C18—H18C109.5O52—C69—C19122.4 (4)
C52—C51—C60123.4 (4)O51—C69—C19110.5 (4)
C52—C51—H51118.3C19—O1—C17117.3 (3)
C60—C51—H51118.3C3—O3—C3A117.7 (4)
C51—C52—C53118.5 (4)C69—O51—C67118.4 (3)
C51—C52—H52120.8C53—O53—C53A117.5 (3)
C10—C1—C2—C31.5 (6)C60—C55—C56—C5719.4 (5)
C1—C2—C3—O3178.3 (3)C55—C56—C57—C5847.5 (4)
C1—C2—C3—C41.4 (6)C56—C57—C58—C64175.4 (3)
C2—C3—C4—C50.1 (6)C56—C57—C58—C5964.0 (4)
O3—C3—C4—C5179.7 (3)C57—C58—C59—C61179.6 (3)
C3—C4—C5—C101.2 (6)C64—C58—C59—C6155.9 (4)
C3—C4—C5—C6176.7 (4)C57—C58—C59—C6050.3 (4)
C4—C5—C6—C7164.2 (3)C64—C58—C59—C60174.0 (3)
C10—C5—C6—C718.0 (5)C52—C51—C60—C550.3 (6)
C5—C6—C7—C845.8 (4)C52—C51—C60—C59176.1 (3)
C6—C7—C8—C14175.7 (3)C54—C55—C60—C510.4 (6)
C6—C7—C8—C963.7 (4)C56—C55—C60—C51177.3 (4)
C14—C8—C9—C10176.1 (3)C54—C55—C60—C59175.4 (3)
C7—C8—C9—C1052.6 (4)C56—C55—C60—C596.9 (6)
C14—C8—C9—C1153.5 (4)C61—C59—C60—C5133.3 (5)
C7—C8—C9—C11177.0 (3)C58—C59—C60—C51162.2 (3)
C2—C1—C10—C50.1 (6)C61—C59—C60—C55151.1 (4)
C2—C1—C10—C9175.6 (4)C58—C59—C60—C5522.2 (5)
C4—C5—C10—C11.2 (5)C60—C59—C61—C62176.0 (3)
C6—C5—C10—C1176.6 (4)C58—C59—C61—C6255.5 (4)
C4—C5—C10—C9174.3 (3)C59—C61—C62—C6354.6 (4)
C6—C5—C10—C97.9 (5)C61—C62—C63—C67163.1 (3)
C11—C9—C10—C129.8 (5)C61—C62—C63—C6870.1 (4)
C8—C9—C10—C1159.4 (3)C61—C62—C63—C6454.4 (4)
C11—C9—C10—C5154.9 (3)C57—C58—C64—C6555.4 (5)
C8—C9—C10—C525.3 (5)C59—C58—C64—C65177.4 (3)
C10—C9—C11—C12178.0 (3)C57—C58—C64—C63180.0 (3)
C8—C9—C11—C1252.8 (4)C59—C58—C64—C6357.9 (4)
C9—C11—C12—C1353.5 (4)C62—C63—C64—C5858.0 (4)
C11—C12—C13—C17165.0 (3)C67—C63—C64—C58178.8 (3)
C11—C12—C13—C1455.3 (4)C68—C63—C64—C5864.9 (4)
C11—C12—C13—C1869.3 (4)C62—C63—C64—C65168.9 (3)
C7—C8—C14—C13178.3 (3)C67—C63—C64—C6548.2 (4)
C9—C8—C14—C1357.3 (4)C68—C63—C64—C6568.1 (4)
C7—C8—C14—C1558.4 (5)C58—C64—C65—C66161.9 (4)
C9—C8—C14—C15179.5 (3)C63—C64—C65—C6633.1 (4)
C12—C13—C14—C859.3 (4)C64—C65—C66—C674.5 (4)
C17—C13—C14—C8178.9 (3)C62—C63—C67—O5179.5 (4)
C18—C13—C14—C863.7 (4)C68—C63—C67—O5147.2 (5)
C12—C13—C14—C15168.9 (3)C64—C63—C67—O51165.1 (3)
C17—C13—C14—C1547.1 (4)C62—C63—C67—C66160.6 (4)
C18—C13—C14—C1568.2 (4)C68—C63—C67—C6672.8 (4)
C8—C14—C15—C16159.1 (3)C64—C63—C67—C6645.2 (4)
C13—C14—C15—C1631.1 (4)C65—C66—C67—O51147.5 (3)
C14—C15—C16—C171.9 (4)C65—C66—C67—C6326.2 (4)
C15—C16—C17—O1149.6 (3)O2—C19—C69—O5259.3 (6)
C15—C16—C17—C1328.2 (4)O1—C19—C69—O52120.6 (4)
C12—C13—C17—O175.2 (4)O2—C19—C69—O51117.4 (4)
C14—C13—C17—O1168.3 (3)O1—C19—C69—O5162.8 (4)
C18—C13—C17—O150.7 (4)O2—C19—O1—C178.1 (6)
C12—C13—C17—C16163.1 (3)C69—C19—O1—C17172.1 (3)
C14—C13—C17—C1646.6 (3)C16—C17—O1—C19135.1 (4)
C18—C13—C17—C1671.0 (4)C13—C17—O1—C19107.1 (4)
C60—C51—C52—C530.6 (6)C2—C3—O3—C3A6.8 (6)
C51—C52—C53—C540.1 (6)C4—C3—O3—C3A173.4 (4)
C51—C52—C53—O53178.9 (3)O52—C69—O51—C671.1 (6)
O53—C53—C54—C55179.7 (4)C19—C69—O51—C67175.3 (3)
C52—C53—C54—C550.6 (6)C63—C67—O51—C69118.8 (4)
C53—C54—C55—C600.9 (6)C66—C67—O51—C69124.1 (4)
C53—C54—C55—C56176.9 (4)C54—C53—O53—C53A175.1 (4)
C54—C55—C56—C57162.9 (3)C52—C53—O53—C53A5.9 (6)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C52—H52···O2i0.952.513.161 (5)126
C53A—H53B···O53ii0.982.513.378 (6)147
C54—H54···O2iii0.952.563.309 (5)136
Symmetry codes: (i) x+1, y+1/2, z+3/2; (ii) x+1/2, y+1/2, z+1; (iii) x, y+1/2, z+3/2.

Experimental details

Crystal data
Chemical formulaC40H50O6
Mr626.80
Crystal system, space groupOrthorhombic, P212121
Temperature (K)120
a, b, c (Å)7.8559 (4), 14.1579 (10), 29.888 (2)
V3)3324.2 (4)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.25 × 0.08 × 0.06
Data collection
DiffractometerNonius KappaCCD
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
21809, 3674, 2220
Rint0.169
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.075, 0.128, 1.02
No. of reflections3674
No. of parameters420
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.32, 0.31

Computer programs: COLLECT (Nonius, 1998), DENZO and SCALEPACK (Otwinowski & Minor, 1997), and SORTAV (Blessing, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C52—H52···O2i0.952.513.161 (5)126
C53A—H53B···O53ii0.982.513.378 (6)147
C54—H54···O2iii0.952.563.309 (5)136
Symmetry codes: (i) x+1, y+1/2, z+3/2; (ii) x+1/2, y+1/2, z+1; (iii) x, y+1/2, z+3/2.
 

Acknowledgements

We thank the EPSRC National Crystallography Service (University of Southampton) for the data collection.

References

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