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In the title compounds, C21H30O4, (I), and C23H34O4, (II), respectively, which are valuable inter­mediates in the synthesis of important steroid derivatives, rings A and B are cis-(5[beta],10[beta])-fused. The two mol­ecules have similar conformations of rings A, B and C. The presence of the 5[beta],6[beta]-epoxide group induces a significant twist of the steroid nucleus and a strong flattening of the B ring. The different C17 substituents result in different conformations for ring D. Cohesion of the mol­ecular packing is achieved in both compounds only by weak inter­molecular inter­actions. The geometries of the mol­ecules in the crystalline environment are compared with those of the free mol­ecules as given by ab initio Roothan Hartree-Fock calculations. We show in this work that quantum mechanical ab initio methods reproduce well the details of the conformation of these mol­ecules, including a large twist of the steroid nucleus. The calculated twist values are comparable, but are larger than the observed values, indicating a possible small effect of the crystal packing on the twist angles.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270108009621/sk3212sup1.cif
Contains datablocks I, II, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S0108270108009621/sk3212Isup2.hkl
Contains datablock I

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S0108270108009621/sk3212IIsup3.hkl
Contains datablock II

CCDC references: 690197; 690198

Comment top

The 5β,6β-epoxide functionality (Salvador et al., 2006) is present in several naturally occurring steroids, in which withanolides are a representative example. These compounds have been studied for anti-inflammatory (Jayaprakasam & Nair, 2003), antitumour (Kuroyanagi et al., 1999), cytotoxic (Veras et al., 2004) and immunomodulatory (Leyon & Kuttan, 2004) activities, as well as for cancer chemoprevention by inducing phase-II enzymes (Misico et al., 2002). Cytotoxic activity against several cell lines has been reported for other naturally occurring 5β,6β-epoxysteroids (Watanabe et al., 1996; Anta et al., 2002). 5β,6β-Epoxysteroids are also valuable intermediates for the synthesis of important compounds, such as brassinosteroid derivatives (Ramírez et al., 2000), laxogenin (Iglesias-Arteaga et al., 2005) and an analogue of squalamine (Cai & Zhou, 2004). In fact, the stereochemistry of these compounds rules their ring opening by nucleophilic agents, which leads to 5α-substituted-6β-hydroxysteroids (Pinto et al., 2006; Pinto, Salvador & Le Roux, 2007; Leitão et al., 2008). Recently, we reported the molecular structure of 5α-acetamido-6β-hydroxy-17-oxoandrostan-3β-yl acetate (Pinto, Ramos Silva et al., 2007) obtained from the reaction of the title compound, (I), with acetonitrile catalysed by BiBr3 (Pinto et al., 2006). The title compounds, (I) and (II), were also used as substrates for the synthesis of new olefinic 18-nor and 18,19-dinorsteroids (Pinto et al., 2008). Thus, attending to the biological and synthetic importance of such molecules, we report here the molecular structures of the title 5β,6β-epoxysteroids, (I) and (II), determined by single-crystal X-ray diffraction, and compare them with those of the free molecules as given by quantum mechanical ab initio calculations.

The structures of compounds (I) and (II), with the corresponding atomic numbering schemes, are shown in Figs. 1 and 2. These two 5β,6β-epoxides are from different steroid series, (I) from androstane with a C17?O carbonyl group at ring D, and (II) from the pregnane series with a methyl ketone group at the side chain. In both molecules, the 3β-acetoxy group is equatorial to ring A, as is the 17β-COCH3 group to ring D of (II).

Rings A and B are cis-(5β,10β)-fused [C1—C10—C5—C4 = -39,6(2)° in (I) and -37.9 (2)° in (II), and C9—C10—C5—C6 = 4.5 (2)° in (I) and 6.2 (3)° in (II)], with a bowing angle between the least-squares planes of rings A and B of 35.43 (9)° and 34.23 (9)° for (I) and (II), respectively.

The pseudo-torsion angle C19—C10···C13—C18 deviates largely from zero in both compounds [18.97 (17)° in (I) and 15.74 (17)° in (II)], showing that the steroid nucleus is significantly twisted. Comparably large pseudo-torsion angles have been observed in other 5β,6β-epoxysteroids (Hanson et al., 2003). This feature appears to be related to the presence of the 5β,6β-epoxide group, as it is absent in other cis-(5β,10β)-fused steroids without this functional group (Andrade et al., 2003; Andrade, Paixão, de Almeida, Tavares da Silva & Fernandes Roleira, 2005).

Average values for the atomic distances are in good agreement with reported ones (Allen et al., 1987), although for the Csp3—Csp3 bond lengths extreme values were found for C5—C6 [1.472 (3) Å in (I) and 1.464 (3) Å in (II)] and C9—C10 [1.567 (3) Å in (I) and 1.566 (2) Å in (II)], deviating significantly from the average values of 1.526 (3) and 1.528 (3) Å for compounds (I) and (II), respectively. Short C2—C3 bonds, common to other related steroids (Andrade, Paixão, de Almeida, Fernandes Roleira & Tavares da Silva, 2005), were also found [1.495 (3) Å in (I) and 1.499 (3) Å in (II)].

In both compounds, rings A and C have slightly flattened conformations intermediate between chair and half-chair, with average torsion angles of 51 (4) and 55 (2)°, respectively, for (I), and 52 (4) and 55 (2)°, respectively, for (II). Ring B of both 5β,6β-epoxysteroids adopts a strongly flattened conformation intermediate between half-chair and envelope, with Cremer & Pople (1975) parameters of Q = 0.5010 (19) Å, θ = 53.1 (2)° and ϕ = 190.7 (3)° for (I), and Q = 0.501 (2) Å, θ = 52.1 (2)° and ϕ = 193.1 (3)° for (II). In fact, as a consequence of the presence of the 5β,6β-epoxide group, atoms C7, C6, C5 and C10 are almost coplanar, as shown by the C7—C6—C5—C10 torsion angle of 1.2 (3)° in (I) and 0.5 (3)° in (II), which results in very low average torsion angles of 34 (10) and 38 (10)° for (I) and (II), respectively.

Ring D of (I) features a C14-envelope conformation, as shown by the Cremer & Pople parameters [q2 = 0.424 (2) Å and ϕ2 = 212.2 (3)°] and asymmetry parameters (Nardelli, 1983) [ΔCs(14) = ΔCs(16,17) = 3.4 (2)°]. In molecule (II), the five-membered ring D has a twisted conformation around the C13—C14 bond [q2 = 0.463 (2) Å, ϕ2 = 192.4 (3)° and ΔC2(16) = Δ2(13,14) = 6.6 (2)°].

Owing to the absence of any strong hydrogen donor, cohesion of the crystal structures of both compounds is mainly achieved by van der Waals and weak C—H···O interactions. In both structures, one weak C—H···O interaction between ring A and epoxide atom O5 links molecules along the a axis. In compound (II), another short contact is found between carbonyl atom O20 and an H atom of a neighbouring C21 methyl group. In addition, an intramolecular C—H···O interaction is present between the same carbonyl atom O20 and an H atom of ring D.

In order to gain some insight into how the crystal packing of (I) and (II) might affect the molecular geometry, and to check whether the large twist of the steroid nucleus is present in the isolated molecules, we have performed a quantum chemical calculation of the equilibrium geometry of the free molecules. These calculations were performed with the computer program GAMESS (Schmidt et al., 1993). A molecular orbital Roothan Hartree–Fock method was used with an extended 6-31G(d,p) basis set. Tight conditions for convergence of both the self-consistent field cycles and the maximum density and energy gradients were imposed (10-5 atomic units). The programs were run on the Milipeia cluster of UC-LCA (16 Opteron cores, 2.2 GHz) running Linux.

Overall, there is very good agreement between the calculated and observed bond lengths, with the exception of the Csp3—O bond lengths of the epoxide group, where the calculated values were systematically shorter than the observed ones: for (I), O5—C5 calculated = 1.414 Å and experimental = 1.456 (2) Å, O5—C6 calculated = 1.407 Å and experimental = 1.435 (3) Å; for (II), O5—C5 calculated = 1.413 Å and experimental = 1.454 (2) Å, O5—C6 calculated = 1.407 Å and experimental = 1.429 (3) Å.

The calculated pseudo-torsion angles C19—C10···C13—C18 were significantly higher than the observed values for both compounds [calculated 22.7° and experimental 18.97 (17)° for (I), and calculated 22.2° and experimental 15.74 (17)° for (II)], showing that the crystal packing somehow affects the steroid nucleus. Interestingly, the calculations reproduce the short C5—C6 bond [calculated 1.459 Å and experimental 1.472 (3) Å for (I), and calculated 1.459 Å and experimental 1.464 (3) Å for (II)] and the long C9—C10 bond [calculated 1.574 Å and experimental 1.567 (3) Å for (I), and calculated 1.574 Å and experimental 1.566 (2) Å for (II)]. In both molecules, a shorter calculated value for the C3—O3A bond binding the 3β-acetoxy substituent to ring A is found [calculated 1.428 Å and experimental 1.462 (2) Å for (I), and calculated 1.429 Å and [experimental?] 1.464 (3) Å for (II)].

Experimental top

The synthesis of both epoxysteroids (I) and (II) was efficiently accomplished by epoxidation with KMnO4/Fe2(SO4)3.nH2O (Salvador et al., 1996). Recrystallization from methanol at room temperature gave colourless single crystals suitable for X-ray analysis. Analytical data for compounds (I) and (II) are in accordance with the literature (Salvador et al., 1996).

Refinement top

All H atoms were refined as riding on their parent atoms, with C—H = 0.96–0.98 Å and with Uiso(H) = 1.2Ueq(C), or 1.5Ueq(C) for methyl H. [Please check added text] The absolute configuration was not determined from the X-ray data but was known from the synthetic route. Friedel pairs were merged before refinement.

Computing details top

For both compounds, data collection: SMART (Bruker, 2003); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii.
[Figure 2] Fig. 2. The molecular structure of (II), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii.
(I) 5β,6β-Epoxy-17-oxoandrostan-3β-yl acetate top
Crystal data top
C21H30O4Dx = 1.202 Mg m3
Mr = 346.45Melting point: 462 K
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 8947 reflections
a = 5.8862 (1) Åθ = 4.7–51.3°
b = 15.0988 (3) ŵ = 0.08 mm1
c = 21.5413 (4) ÅT = 293 K
V = 1914.47 (6) Å3Long square prism, colourless
Z = 40.37 × 0.12 × 0.11 mm
F(000) = 752.0
Data collection top
Bruker APEX CCD area-detector
diffractometer
2609 independent reflections
Radiation source: fine-focus sealed tube2155 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.029
ϕ and ω scansθmax = 27.9°, θmin = 2.7°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2000)
h = 77
Tmin = 0.928, Tmax = 1.000k = 1919
62065 measured reflectionsl = 2727
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)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.123H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0805P)2 + 0.1688P]
where P = (Fo2 + 2Fc2)/3
2609 reflections(Δ/σ)max < 0.001
229 parametersΔρmax = 0.28 e Å3
0 restraintsΔρmin = 0.19 e Å3
Crystal data top
C21H30O4V = 1914.47 (6) Å3
Mr = 346.45Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 5.8862 (1) ŵ = 0.08 mm1
b = 15.0988 (3) ÅT = 293 K
c = 21.5413 (4) Å0.37 × 0.12 × 0.11 mm
Data collection top
Bruker APEX CCD area-detector
diffractometer
2609 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2000)
2155 reflections with I > 2σ(I)
Tmin = 0.928, Tmax = 1.000Rint = 0.029
62065 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.123H-atom parameters constrained
S = 1.02Δρmax = 0.28 e Å3
2609 reflectionsΔρmin = 0.19 e Å3
229 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
O3A0.7278 (4)0.80189 (9)0.40926 (7)0.0621 (5)
O3B0.7562 (5)0.83418 (13)0.30919 (9)0.0953 (8)
O50.4140 (2)0.51801 (10)0.34587 (7)0.0513 (4)
O171.1917 (3)0.10859 (11)0.35421 (9)0.0753 (5)
C10.9511 (4)0.57417 (13)0.43919 (10)0.0477 (5)
H1A1.01730.54810.47620.057*
H1B1.06870.57590.40770.057*
C20.8816 (5)0.66928 (13)0.45424 (10)0.0534 (5)
H2A0.76860.66970.48700.064*
H2B1.01250.70290.46820.064*
C30.7859 (4)0.70952 (12)0.39650 (9)0.0476 (5)
H30.89950.70700.36330.057*
C3A0.7214 (6)0.85705 (15)0.36172 (11)0.0672 (7)
C3B0.6595 (10)0.94920 (16)0.37946 (14)0.1103 (16)
H21A0.67480.98730.34400.166*
H21B0.75870.96930.41190.166*
H21C0.50530.95050.39390.166*
C40.5768 (4)0.65952 (13)0.37686 (11)0.0499 (5)
H4A0.51820.68540.33890.060*
H4B0.46110.66590.40860.060*
C50.6218 (3)0.56152 (12)0.36615 (9)0.0388 (4)
C60.5989 (4)0.52584 (13)0.30285 (9)0.0450 (5)
H60.57950.56970.26970.054*
C70.7024 (4)0.43955 (12)0.28392 (8)0.0460 (5)
H7A0.84650.45070.26350.055*
H7B0.60310.41040.25430.055*
C80.7411 (3)0.37819 (11)0.33939 (7)0.0347 (4)
H80.59460.35930.35650.042*
C90.8783 (3)0.42801 (11)0.38948 (7)0.0343 (4)
H91.01510.44970.36840.041*
C100.7582 (3)0.51249 (12)0.41608 (8)0.0373 (4)
C110.9643 (4)0.36572 (13)0.44133 (9)0.0485 (5)
H11A1.06520.39870.46840.058*
H11B0.83550.34650.46600.058*
C121.0894 (4)0.28435 (14)0.41742 (10)0.0516 (5)
H12A1.22890.30230.39700.062*
H12B1.12870.24600.45190.062*
C130.9390 (3)0.23451 (12)0.37189 (9)0.0398 (4)
C140.8763 (3)0.29785 (12)0.31871 (8)0.0376 (4)
H141.02040.32070.30250.045*
C150.7810 (4)0.23605 (14)0.26826 (9)0.0529 (5)
H15A0.62600.21860.27750.063*
H15B0.78530.26400.22770.063*
C160.9415 (5)0.15704 (16)0.27124 (11)0.0622 (6)
H16A1.05860.16210.23970.075*
H16B0.85880.10230.26460.075*
C171.0466 (4)0.15836 (14)0.33588 (10)0.0492 (5)
C180.7324 (4)0.19280 (14)0.40437 (10)0.0548 (6)
H18A0.64690.23820.42510.082*
H18B0.78340.15000.43420.082*
H18C0.63790.16420.37410.082*
C190.5945 (4)0.49110 (16)0.46942 (10)0.0574 (6)
H19A0.48930.44630.45630.086*
H19B0.51250.54360.48080.086*
H19C0.67930.47010.50450.086*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O3A0.0990 (13)0.0369 (7)0.0506 (8)0.0040 (9)0.0091 (9)0.0042 (6)
O3B0.148 (2)0.0760 (12)0.0618 (11)0.0227 (16)0.0193 (14)0.0086 (9)
O50.0323 (6)0.0533 (8)0.0683 (9)0.0019 (6)0.0096 (7)0.0008 (7)
O170.0753 (12)0.0607 (10)0.0900 (11)0.0301 (9)0.0125 (10)0.0092 (9)
C10.0471 (11)0.0460 (11)0.0500 (10)0.0022 (9)0.0117 (9)0.0097 (9)
C20.0619 (12)0.0458 (11)0.0524 (11)0.0034 (10)0.0062 (11)0.0115 (9)
C30.0605 (12)0.0364 (10)0.0458 (10)0.0004 (9)0.0068 (10)0.0052 (8)
C3A0.104 (2)0.0448 (11)0.0531 (13)0.0018 (13)0.0087 (14)0.0007 (10)
C3B0.214 (5)0.0443 (13)0.0732 (16)0.015 (2)0.002 (3)0.0024 (12)
C40.0527 (12)0.0407 (10)0.0564 (12)0.0081 (9)0.0054 (10)0.0028 (9)
C50.0313 (8)0.0384 (9)0.0467 (9)0.0012 (7)0.0021 (8)0.0040 (8)
C60.0474 (10)0.0418 (10)0.0458 (10)0.0006 (9)0.0117 (9)0.0079 (8)
C70.0574 (12)0.0428 (10)0.0380 (9)0.0012 (9)0.0081 (9)0.0038 (8)
C80.0334 (8)0.0367 (9)0.0339 (8)0.0043 (7)0.0019 (7)0.0031 (7)
C90.0320 (8)0.0371 (9)0.0338 (8)0.0012 (7)0.0018 (7)0.0021 (7)
C100.0369 (9)0.0382 (9)0.0366 (8)0.0010 (8)0.0001 (7)0.0027 (7)
C110.0617 (13)0.0421 (10)0.0418 (10)0.0064 (10)0.0166 (10)0.0010 (8)
C120.0536 (12)0.0466 (11)0.0547 (11)0.0094 (10)0.0168 (10)0.0018 (9)
C130.0418 (10)0.0362 (9)0.0413 (9)0.0035 (8)0.0018 (8)0.0019 (8)
C140.0380 (9)0.0383 (9)0.0365 (8)0.0032 (8)0.0006 (8)0.0020 (7)
C150.0648 (13)0.0474 (11)0.0464 (10)0.0037 (11)0.0081 (10)0.0078 (9)
C160.0826 (17)0.0519 (12)0.0522 (12)0.0094 (13)0.0016 (12)0.0113 (10)
C170.0488 (11)0.0419 (11)0.0569 (12)0.0029 (9)0.0042 (10)0.0007 (9)
C180.0627 (13)0.0426 (10)0.0593 (12)0.0004 (10)0.0176 (12)0.0106 (10)
C190.0593 (13)0.0620 (13)0.0511 (11)0.0072 (12)0.0169 (11)0.0105 (10)
Geometric parameters (Å, º) top
O3A—C3A1.320 (3)C8—C91.544 (2)
O3A—C31.462 (2)C8—H80.9800
O3B—C3A1.201 (3)C9—C111.545 (2)
O5—C61.435 (3)C9—C101.567 (3)
O5—C51.456 (2)C9—H90.9800
O17—C171.204 (3)C10—C191.534 (3)
C1—C21.528 (3)C11—C121.522 (3)
C1—C101.551 (3)C11—H11A0.9700
C1—H1A0.9700C11—H11B0.9700
C1—H1B0.9700C12—C131.520 (3)
C2—C31.495 (3)C12—H12A0.9700
C2—H2A0.9700C12—H12B0.9700
C2—H2B0.9700C13—C171.525 (3)
C3—C41.505 (3)C13—C141.537 (3)
C3—H30.9800C13—C181.538 (3)
C3A—C3B1.488 (4)C14—C151.539 (3)
C3B—H21A0.9600C14—H140.9800
C3B—H21B0.9600C15—C161.523 (3)
C3B—H21C0.9600C15—H15A0.9700
C4—C51.521 (3)C15—H15B0.9700
C4—H4A0.9700C16—C171.524 (3)
C4—H4B0.9700C16—H16A0.9700
C5—C61.472 (3)C16—H16B0.9700
C5—C101.533 (2)C18—H18A0.9600
C6—C71.495 (3)C18—H18B0.9600
C6—H60.9800C18—H18C0.9600
C7—C81.529 (2)C19—H19A0.9600
C7—H7A0.9700C19—H19B0.9600
C7—H7B0.9700C19—H19C0.9600
C8—C141.518 (2)
C3A—O3A—C3117.55 (16)C11—C9—C10112.26 (14)
C6—O5—C561.24 (12)C8—C9—H9105.6
C2—C1—C10115.87 (19)C11—C9—H9105.6
C2—C1—H1A108.3C10—C9—H9105.6
C10—C1—H1A108.3C5—C10—C19107.38 (17)
C2—C1—H1B108.3C5—C10—C1108.58 (14)
C10—C1—H1B108.3C19—C10—C1110.24 (16)
H1A—C1—H1B107.4C5—C10—C9111.89 (14)
C3—C2—C1107.84 (17)C19—C10—C9112.71 (15)
C3—C2—H2A110.1C1—C10—C9105.99 (15)
C1—C2—H2A110.1C12—C11—C9113.90 (16)
C3—C2—H2B110.1C12—C11—H11A108.8
C1—C2—H2B110.1C9—C11—H11A108.8
H2A—C2—H2B108.5C12—C11—H11B108.8
O3A—C3—C2108.64 (15)C9—C11—H11B108.8
O3A—C3—C4109.88 (19)H11A—C11—H11B107.7
C2—C3—C4109.79 (18)C13—C12—C11109.64 (17)
O3A—C3—H3109.5C13—C12—H12A109.7
C2—C3—H3109.5C11—C12—H12A109.7
C4—C3—H3109.5C13—C12—H12B109.7
O3B—C3A—O3A123.0 (2)C11—C12—H12B109.7
O3B—C3A—C3B123.5 (2)H12A—C12—H12B108.2
O3A—C3A—C3B113.4 (2)C12—C13—C17117.37 (17)
C3A—C3B—H21A109.5C12—C13—C14108.21 (15)
C3A—C3B—H21B109.5C17—C13—C14100.94 (15)
H21A—C3B—H21B109.5C12—C13—C18111.69 (17)
C3A—C3B—H21C109.5C17—C13—C18104.54 (16)
H21A—C3B—H21C109.5C14—C13—C18113.82 (17)
H21B—C3B—H21C109.5C8—C14—C13113.86 (14)
C3—C4—C5112.84 (18)C8—C14—C15120.04 (17)
C3—C4—H4A109.0C13—C14—C15103.69 (15)
C5—C4—H4A109.0C8—C14—H14106.1
C3—C4—H4B109.0C13—C14—H14106.1
C5—C4—H4B109.0C15—C14—H14106.1
H4A—C4—H4B107.8C16—C15—C14102.64 (17)
O5—C5—C658.67 (12)C16—C15—H15A111.2
O5—C5—C4109.76 (16)C14—C15—H15A111.2
C6—C5—C4118.72 (17)C16—C15—H15B111.2
O5—C5—C10115.64 (15)C14—C15—H15B111.2
C6—C5—C10121.41 (16)H15A—C15—H15B109.2
C4—C5—C10117.05 (17)C15—C16—C17106.27 (17)
O5—C6—C560.09 (12)C15—C16—H16A110.5
O5—C6—C7114.43 (16)C17—C16—H16A110.5
C5—C6—C7122.29 (16)C15—C16—H16B110.5
O5—C6—H6116.0C17—C16—H16B110.5
C5—C6—H6116.0H16A—C16—H16B108.7
C7—C6—H6116.0O17—C17—C16125.4 (2)
C6—C7—C8112.07 (16)O17—C17—C13126.8 (2)
C6—C7—H7A109.2C16—C17—C13107.83 (18)
C8—C7—H7A109.2C13—C18—H18A109.5
C6—C7—H7B109.2C13—C18—H18B109.5
C8—C7—H7B109.2H18A—C18—H18B109.5
H7A—C7—H7B107.9C13—C18—H18C109.5
C14—C8—C7109.46 (14)H18A—C18—H18C109.5
C14—C8—C9108.67 (14)H18B—C18—H18C109.5
C7—C8—C9109.20 (14)C10—C19—H19A109.5
C14—C8—H8109.8C10—C19—H19B109.5
C7—C8—H8109.8H19A—C19—H19B109.5
C9—C8—H8109.8C10—C19—H19C109.5
C8—C9—C11112.33 (14)H19A—C19—H19C109.5
C8—C9—C10114.59 (14)H19B—C19—H19C109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1B···O5i0.972.583.490 (3)156
Symmetry code: (i) x+1, y, z.
(II) 5β,6β-Epoxy-20-oxopregnan-3β-yl acetate top
Crystal data top
C23H34O4Dx = 1.189 Mg m3
Mr = 374.50Melting point: 403 K
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 6859 reflections
a = 6.2955 (1) Åθ = 2.8–24.7°
b = 11.8930 (1) ŵ = 0.08 mm1
c = 27.9396 (4) ÅT = 293 K
V = 2091.90 (5) Å3Block, colourless
Z = 40.30 × 0.28 × 0.17 mm
F(000) = 816.0
Data collection top
Bruker APEX CCD area-detector
diffractometer
2940 independent reflections
Radiation source: fine-focus sealed tube2530 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.025
ϕ and ω scansθmax = 28.1°, θmin = 1.5°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2000)
h = 88
Tmin = 0.955, Tmax = 1.000k = 1515
56880 measured reflectionsl = 3637
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)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.127H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0734P)2 + 0.2544P]
where P = (Fo2 + 2Fc2)/3
2940 reflections(Δ/σ)max = 0.002
248 parametersΔρmax = 0.20 e Å3
0 restraintsΔρmin = 0.20 e Å3
Crystal data top
C23H34O4V = 2091.90 (5) Å3
Mr = 374.50Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 6.2955 (1) ŵ = 0.08 mm1
b = 11.8930 (1) ÅT = 293 K
c = 27.9396 (4) Å0.30 × 0.28 × 0.17 mm
Data collection top
Bruker APEX CCD area-detector
diffractometer
2940 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2000)
2530 reflections with I > 2σ(I)
Tmin = 0.955, Tmax = 1.000Rint = 0.025
56880 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0410 restraints
wR(F2) = 0.127H-atom parameters constrained
S = 1.05Δρmax = 0.20 e Å3
2940 reflectionsΔρmin = 0.20 e Å3
248 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
C10.9199 (3)0.00374 (17)0.10484 (8)0.0512 (5)
H1A0.96300.01970.07220.061*
H1B1.01440.04500.12590.061*
C20.9510 (4)0.12158 (19)0.11405 (8)0.0571 (5)
H2A0.86410.16530.09230.068*
H2B1.09850.14210.10920.068*
C30.8870 (4)0.14441 (17)0.16481 (8)0.0525 (5)
H30.97130.09790.18660.063*
O3A0.9213 (3)0.26357 (13)0.17542 (6)0.0618 (4)
C3A0.9611 (4)0.2899 (2)0.22085 (9)0.0622 (6)
O3B0.9768 (5)0.22099 (19)0.25216 (7)0.0895 (7)
C3B0.9740 (5)0.4140 (2)0.22854 (11)0.0777 (8)
H3BA1.10880.44110.21730.117*
H3BB0.86190.45040.21120.117*
H3BC0.95980.43020.26210.117*
C40.6534 (4)0.11915 (18)0.17125 (8)0.0546 (5)
H4A0.61370.13380.20420.066*
H4B0.57120.16910.15100.066*
C50.5991 (3)0.00191 (16)0.15888 (7)0.0440 (4)
O50.3729 (2)0.02051 (13)0.16584 (6)0.0551 (4)
C60.5202 (4)0.07591 (18)0.19680 (7)0.0497 (5)
H60.52950.04590.22940.060*
C70.5220 (4)0.20124 (17)0.19269 (7)0.0506 (5)
H7A0.64590.23070.20910.061*
H7B0.39670.23160.20820.061*
C80.5261 (3)0.23920 (15)0.14046 (6)0.0394 (4)
H80.39120.21990.12500.047*
C90.7099 (3)0.18047 (15)0.11440 (6)0.0405 (4)
H90.83670.19580.13370.049*
C100.6917 (3)0.04926 (16)0.11204 (7)0.0411 (4)
C110.7542 (4)0.23313 (18)0.06511 (8)0.0594 (6)
H11A0.88370.20080.05230.071*
H11B0.63910.21350.04360.071*
C120.7773 (4)0.36164 (18)0.06616 (8)0.0571 (5)
H12A0.90270.38180.08440.069*
H12B0.79540.38950.03380.069*
C130.5819 (3)0.41642 (16)0.08871 (6)0.0430 (4)
C140.5591 (3)0.36612 (15)0.13895 (6)0.0420 (4)
H140.69400.38050.15530.050*
C150.3950 (5)0.44052 (18)0.16330 (8)0.0611 (6)
H15A0.41120.43840.19780.073*
H15B0.25200.41720.15510.073*
C160.4432 (5)0.55896 (19)0.14354 (9)0.0686 (7)
H16A0.31410.59410.13190.082*
H16B0.50340.60610.16840.082*
C170.6032 (4)0.54363 (17)0.10237 (7)0.0548 (5)
H170.74600.55530.11540.066*
C180.3851 (5)0.3996 (2)0.05751 (8)0.0647 (6)
H18A0.41010.43090.02630.097*
H18B0.26580.43660.07200.097*
H18C0.35570.32070.05460.097*
C190.5469 (4)0.00946 (18)0.07137 (8)0.0541 (5)
H19A0.61310.02520.04120.081*
H19B0.41330.04820.07320.081*
H19C0.52340.07000.07430.081*
C200.5726 (6)0.6254 (2)0.06142 (10)0.0781 (8)
O200.4182 (6)0.6851 (2)0.05948 (10)0.1422 (14)
C210.7391 (8)0.6324 (2)0.02447 (10)0.1016 (13)
H21A0.71640.57480.00090.152*
H21B0.87580.62210.03900.152*
H21C0.73370.70480.00930.152*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0457 (10)0.0516 (11)0.0564 (11)0.0057 (9)0.0086 (9)0.0022 (9)
C20.0549 (12)0.0532 (11)0.0632 (12)0.0106 (10)0.0033 (11)0.0042 (10)
C30.0560 (12)0.0422 (9)0.0594 (12)0.0049 (10)0.0048 (10)0.0009 (9)
O3A0.0741 (11)0.0475 (7)0.0636 (9)0.0124 (8)0.0062 (9)0.0019 (7)
C3A0.0522 (12)0.0676 (14)0.0667 (14)0.0130 (11)0.0020 (12)0.0115 (11)
O3B0.1167 (18)0.0869 (13)0.0648 (10)0.0111 (14)0.0086 (12)0.0028 (10)
C3B0.0740 (17)0.0721 (15)0.0870 (18)0.0229 (15)0.0104 (16)0.0225 (14)
C40.0584 (12)0.0478 (10)0.0577 (12)0.0010 (10)0.0030 (10)0.0089 (9)
C50.0376 (9)0.0473 (10)0.0470 (10)0.0004 (8)0.0008 (8)0.0052 (8)
O50.0391 (7)0.0613 (8)0.0651 (9)0.0017 (7)0.0070 (7)0.0088 (7)
C60.0520 (11)0.0569 (11)0.0400 (9)0.0043 (10)0.0047 (9)0.0091 (8)
C70.0620 (13)0.0535 (10)0.0365 (9)0.0077 (10)0.0083 (9)0.0038 (8)
C80.0394 (9)0.0448 (9)0.0341 (8)0.0012 (8)0.0033 (7)0.0006 (7)
C90.0368 (9)0.0452 (9)0.0396 (9)0.0005 (8)0.0049 (8)0.0007 (7)
C100.0383 (9)0.0460 (9)0.0390 (8)0.0001 (8)0.0005 (8)0.0005 (7)
C110.0763 (16)0.0511 (11)0.0509 (11)0.0051 (11)0.0282 (12)0.0033 (9)
C120.0613 (13)0.0513 (11)0.0587 (12)0.0008 (11)0.0236 (11)0.0080 (10)
C130.0458 (10)0.0449 (9)0.0382 (9)0.0011 (8)0.0035 (8)0.0025 (7)
C140.0461 (10)0.0458 (9)0.0341 (8)0.0011 (8)0.0000 (8)0.0009 (7)
C150.0811 (17)0.0525 (11)0.0498 (11)0.0117 (12)0.0193 (12)0.0012 (9)
C160.0933 (19)0.0514 (11)0.0611 (13)0.0133 (13)0.0190 (14)0.0033 (10)
C170.0666 (14)0.0458 (10)0.0521 (11)0.0002 (11)0.0041 (11)0.0028 (8)
C180.0690 (15)0.0722 (15)0.0529 (12)0.0060 (13)0.0156 (12)0.0082 (11)
C190.0583 (12)0.0553 (11)0.0486 (10)0.0059 (10)0.0062 (10)0.0030 (9)
C200.111 (2)0.0506 (12)0.0729 (16)0.0077 (16)0.0162 (17)0.0149 (12)
O200.171 (3)0.129 (2)0.127 (2)0.075 (2)0.041 (2)0.0736 (18)
C210.164 (4)0.0633 (15)0.0771 (17)0.006 (2)0.047 (2)0.0111 (13)
Geometric parameters (Å, º) top
C1—C21.525 (3)C9—H90.9800
C1—C101.548 (3)C10—C191.532 (3)
C1—H1A0.9700C11—C121.536 (3)
C1—H1B0.9700C11—H11A0.9700
C2—C31.499 (3)C11—H11B0.9700
C2—H2A0.9700C12—C131.528 (3)
C2—H2B0.9700C12—H12A0.9700
C3—O3A1.464 (3)C12—H12B0.9700
C3—C41.512 (3)C13—C181.528 (3)
C3—H30.9800C13—C141.533 (2)
O3A—C3A1.331 (3)C13—C171.566 (3)
C3A—O3B1.202 (3)C14—C151.521 (3)
C3A—C3B1.494 (4)C14—H140.9800
C3B—H3BA0.9600C15—C161.543 (3)
C3B—H3BB0.9600C15—H15A0.9700
C3B—H3BC0.9600C15—H15B0.9700
C4—C51.520 (3)C16—C171.540 (3)
C4—H4A0.9700C16—H16A0.9700
C4—H4B0.9700C16—H16B0.9700
C5—O51.454 (2)C17—C201.514 (3)
C5—C61.464 (3)C17—H170.9800
C5—C101.540 (3)C18—H18A0.9600
O5—C61.429 (3)C18—H18B0.9600
C6—C71.495 (3)C18—H18C0.9600
C6—H60.9800C19—H19A0.9600
C7—C81.528 (2)C19—H19B0.9600
C7—H7A0.9700C19—H19C0.9600
C7—H7B0.9700C20—O201.205 (4)
C8—C141.524 (3)C20—C211.474 (4)
C8—C91.535 (3)C21—H21A0.9600
C8—H80.9800C21—H21B0.9600
C9—C111.538 (3)C21—H21C0.9600
C9—C101.566 (2)
C2—C1—C10116.05 (18)C5—C10—C1109.51 (16)
C2—C1—H1A108.3C19—C10—C9112.50 (16)
C10—C1—H1A108.3C5—C10—C9110.89 (15)
C2—C1—H1B108.3C1—C10—C9106.62 (16)
C10—C1—H1B108.3C12—C11—C9113.91 (17)
H1A—C1—H1B107.4C12—C11—H11A108.8
C3—C2—C1107.58 (17)C9—C11—H11A108.8
C3—C2—H2A110.2C12—C11—H11B108.8
C1—C2—H2A110.2C9—C11—H11B108.8
C3—C2—H2B110.2H11A—C11—H11B107.7
C1—C2—H2B110.2C13—C12—C11110.86 (18)
H2A—C2—H2B108.5C13—C12—H12A109.5
O3A—C3—C2109.10 (17)C11—C12—H12A109.5
O3A—C3—C4108.17 (19)C13—C12—H12B109.5
C2—C3—C4109.77 (19)C11—C12—H12B109.5
O3A—C3—H3109.9H12A—C12—H12B108.1
C2—C3—H3109.9C12—C13—C18111.19 (17)
C4—C3—H3109.9C12—C13—C14106.67 (17)
C3A—O3A—C3116.63 (18)C18—C13—C14113.26 (17)
O3B—C3A—O3A123.3 (2)C12—C13—C17116.35 (18)
O3B—C3A—C3B124.3 (2)C18—C13—C17109.57 (18)
O3A—C3A—C3B112.3 (2)C14—C13—C1799.32 (14)
C3A—C3B—H3BA109.5C15—C14—C8118.12 (17)
C3A—C3B—H3BB109.5C15—C14—C13104.27 (16)
H3BA—C3B—H3BB109.5C8—C14—C13115.14 (15)
C3A—C3B—H3BC109.5C15—C14—H14106.1
H3BA—C3B—H3BC109.5C8—C14—H14106.1
H3BB—C3B—H3BC109.5C13—C14—H14106.1
C3—C4—C5112.33 (18)C14—C15—C16103.75 (19)
C3—C4—H4A109.1C14—C15—H15A111.0
C5—C4—H4A109.1C16—C15—H15A111.0
C3—C4—H4B109.1C14—C15—H15B111.0
C5—C4—H4B109.1C16—C15—H15B111.0
H4A—C4—H4B107.9H15A—C15—H15B109.0
O5—C5—C658.65 (13)C17—C16—C15106.72 (18)
O5—C5—C4109.51 (17)C17—C16—H16A110.4
C6—C5—C4118.77 (17)C15—C16—H16A110.4
O5—C5—C10115.40 (17)C17—C16—H16B110.4
C6—C5—C10121.58 (16)C15—C16—H16B110.4
C4—C5—C10117.05 (17)H16A—C16—H16B108.6
C6—O5—C561.03 (13)C20—C17—C16113.9 (2)
O5—C6—C560.32 (13)C20—C17—C13115.20 (19)
O5—C6—C7114.72 (18)C16—C17—C13103.92 (18)
C5—C6—C7122.76 (17)C20—C17—H17107.8
O5—C6—H6115.7C16—C17—H17107.8
C5—C6—H6115.7C13—C17—H17107.8
C7—C6—H6115.7C13—C18—H18A109.5
C6—C7—C8111.60 (16)C13—C18—H18B109.5
C6—C7—H7A109.3H18A—C18—H18B109.5
C8—C7—H7A109.3C13—C18—H18C109.5
C6—C7—H7B109.3H18A—C18—H18C109.5
C8—C7—H7B109.3H18B—C18—H18C109.5
H7A—C7—H7B108.0C10—C19—H19A109.5
C14—C8—C7108.75 (15)C10—C19—H19B109.5
C14—C8—C9109.56 (15)H19A—C19—H19B109.5
C7—C8—C9109.35 (15)C10—C19—H19C109.5
C14—C8—H8109.7H19A—C19—H19C109.5
C7—C8—H8109.7H19B—C19—H19C109.5
C9—C8—H8109.7O20—C20—C21120.6 (3)
C8—C9—C11112.08 (16)O20—C20—C17121.0 (3)
C8—C9—C10114.71 (16)C21—C20—C17118.4 (3)
C11—C9—C10112.42 (15)C20—C21—H21A109.5
C8—C9—H9105.6C20—C21—H21B109.5
C11—C9—H9105.6H21A—C21—H21B109.5
C10—C9—H9105.6C20—C21—H21C109.5
C19—C10—C5106.99 (16)H21A—C21—H21C109.5
C19—C10—C1110.35 (17)H21B—C21—H21C109.5
C10—C1—C2—C358.9 (3)C2—C1—C10—C9165.02 (17)
C1—C2—C3—O3A178.22 (18)C8—C9—C10—C1982.1 (2)
C1—C2—C3—C463.4 (2)C11—C9—C10—C1947.6 (2)
C2—C3—O3A—C3A152.2 (2)C8—C9—C10—C537.7 (2)
C4—C3—O3A—C3A88.4 (2)C11—C9—C10—C5167.33 (18)
C3—O3A—C3A—O3B2.7 (4)C8—C9—C10—C1156.86 (16)
C3—O3A—C3A—C3B174.8 (2)C11—C9—C10—C173.5 (2)
O3A—C3—C4—C5177.45 (16)C8—C9—C11—C1250.1 (3)
C2—C3—C4—C558.5 (2)C10—C9—C11—C12178.9 (2)
C3—C4—C5—O5179.98 (18)C9—C11—C12—C1355.3 (3)
C3—C4—C5—C6115.8 (2)C11—C12—C13—C1866.5 (2)
C3—C4—C5—C1046.3 (3)C11—C12—C13—C1457.4 (2)
C4—C5—O5—C6112.46 (19)C11—C12—C13—C17167.11 (18)
C10—C5—O5—C6112.93 (18)C7—C8—C14—C1559.9 (2)
C5—O5—C6—C7115.0 (2)C9—C8—C14—C15179.40 (17)
C4—C5—C6—O596.4 (2)C7—C8—C14—C13176.05 (17)
C10—C5—C6—O5102.4 (2)C9—C8—C14—C1356.6 (2)
O5—C5—C6—C7101.9 (2)C12—C13—C14—C15168.17 (18)
C4—C5—C6—C7161.7 (2)C18—C13—C14—C1569.2 (2)
C10—C5—C6—C70.5 (3)C17—C13—C14—C1546.9 (2)
O5—C6—C7—C846.2 (3)C12—C13—C14—C860.8 (2)
C5—C6—C7—C823.2 (3)C18—C13—C14—C861.9 (2)
C6—C7—C8—C14172.16 (19)C17—C13—C14—C8177.97 (18)
C6—C7—C8—C952.6 (2)C8—C14—C15—C16165.32 (19)
C14—C8—C9—C1148.5 (2)C13—C14—C15—C1636.1 (2)
C7—C8—C9—C11167.60 (18)C14—C15—C16—C1710.1 (3)
C14—C8—C9—C10178.27 (15)C15—C16—C17—C20144.8 (2)
C7—C8—C9—C1062.6 (2)C15—C16—C17—C1318.6 (3)
O5—C5—C10—C1949.4 (2)C12—C13—C17—C2081.2 (3)
C6—C5—C10—C19116.8 (2)C18—C13—C17—C2046.0 (3)
C4—C5—C10—C1981.7 (2)C14—C13—C17—C20164.9 (2)
O5—C5—C10—C1169.02 (17)C12—C13—C17—C16153.5 (2)
C6—C5—C10—C1123.6 (2)C18—C13—C17—C1679.3 (2)
C4—C5—C10—C137.9 (2)C14—C13—C17—C1639.6 (2)
O5—C5—C10—C973.6 (2)C16—C17—C20—O209.6 (4)
C6—C5—C10—C96.2 (3)C13—C17—C20—O20110.3 (3)
C4—C5—C10—C9155.30 (18)C16—C17—C20—C21168.9 (3)
C2—C1—C10—C1972.5 (2)C13—C17—C20—C2171.1 (4)
C2—C1—C10—C545.0 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1B···O5i0.972.533.329 (3)139
C16—H16A···O200.972.392.791 (3)105
C21—H21C···O20ii0.962.603.389 (3)140
Symmetry codes: (i) x+1, y, z; (ii) x+1/2, y+3/2, z.

Experimental details

(I)(II)
Crystal data
Chemical formulaC21H30O4C23H34O4
Mr346.45374.50
Crystal system, space groupOrthorhombic, P212121Orthorhombic, P212121
Temperature (K)293293
a, b, c (Å)5.8862 (1), 15.0988 (3), 21.5413 (4)6.2955 (1), 11.8930 (1), 27.9396 (4)
V3)1914.47 (6)2091.90 (5)
Z44
Radiation typeMo KαMo Kα
µ (mm1)0.080.08
Crystal size (mm)0.37 × 0.12 × 0.110.30 × 0.28 × 0.17
Data collection
DiffractometerBruker APEX CCD area-detector
diffractometer
Bruker APEX CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2000)
Multi-scan
(SADABS; Sheldrick, 2000)
Tmin, Tmax0.928, 1.0000.955, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
62065, 2609, 2155 56880, 2940, 2530
Rint0.0290.025
(sin θ/λ)max1)0.6580.663
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.123, 1.02 0.041, 0.127, 1.05
No. of reflections26092940
No. of parameters229248
H-atom treatmentH-atom parameters constrainedH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.28, 0.190.20, 0.20

Computer programs: SMART (Bruker, 2003), SAINT (Bruker, 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2003).

Selected bond lengths (Å) for (I) top
O5—C61.435 (3)C5—C61.472 (3)
O5—C51.456 (2)C9—C101.567 (3)
C2—C31.495 (3)
Hydrogen-bond geometry (Å, º) for (I) top
D—H···AD—HH···AD···AD—H···A
C1—H1B···O5i0.972.583.490 (3)156.0
Symmetry code: (i) x+1, y, z.
Selected bond lengths (Å) for (II) top
C2—C31.499 (3)C5—C61.464 (3)
C5—O51.454 (2)C9—C101.566 (2)
Hydrogen-bond geometry (Å, º) for (II) top
D—H···AD—HH···AD···AD—H···A
C1—H1B···O5i0.972.533.329 (3)139.0
C16—H16A···O200.972.392.791 (3)104.5
C21—H21C···O20ii0.962.603.389 (3)139.6
Symmetry codes: (i) x+1, y, z; (ii) x+1/2, y+3/2, z.
 

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