organic compounds
(25R)-16β-Acetoxy-3β-bromo-23′,26-epoxy-23′,25-dimethyl-5α-cholest-23,23′-en-6-one dichloromethane monosolvate
aDivisión de Posgrado, Instituto Tecnológico de Mérida, Avenida Tecnológico, Km 4.5 S/N C.P. 97118, Mérida Yucatán, Mexico, bDepartamento de Química, CINVESTAV–IPN, Apdo. Postal 14-740, 07000 México, D.F., Mexico, cInstituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, C.P. 58000, Mexico, and dFacultad de Química, Departamento de Química Orgánica, Universidad Nacional Autónoma de México, México D.F., 04510, Mexico
*Correspondence e-mail: susana74a@yahoo.com
The 31H45BrO5·CH2Cl2, prepared in six steps from diosgenin, confirmed that the configurations of the stereogenic centers, positions 20S and 25R, remain unchanged during the reaction. The six-membered A, B and C rings have chair conformations. The five-membered ring D has an (with the methyl-substituted C atom fused to ring C as the flap) and the six-membered dihydropyran ring E adopts a twist-boat conformation. In the crystal, molecules are linked via C—H⋯O and C—H⋯Cl hydrogen bonds, the latter involving the dichloromethane solvent molecule, forming a three-dimensional supramolecular network.
of the title compound, CRelated literature
For a review on saponins, see: Hostettmann & Marston (1995). For the use of spirostane sapogenins in the synthesis of biologically active compounds, see: Lee et al. (1976, 2009); Phillips & Shair (2007); Pettit et al. (1988). For compounds used in the sythesis and for various details of the synthetic procedure, see: Corey & Suggs (1975); Steele & Mosettig (1963); Iglesias-Arteaga et al. (1998); Monroe & Serota (1956); Rincón et al. (2006). For the of a related steroidal compound containing bromine in the same position, see: Castro-Méndez et al. (2002). For standard bond lengths, see: Allen et al. (1987). For see: Cremer & Pople (1975).
Experimental
Crystal data
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Data collection
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Data collection: COLLECT (Nonius, 1999); cell SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO (Otwinowski & Minor, 1997) and SCALEPACK; program(s) used to solve structure: SHELXS97 (Sheldrick 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 2012).
Supporting information
10.1107/S1600536812043590/su2514sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536812043590/su2514Isup2.hkl
Tosylation of diosgenin with TsCl in pyridine (Monroe et al., 1956), followed by preparation of the i-steroid derivative using a methodology previously described (Steele et al., 1963), oxidation with PDC (Corey & Suggs, 1975) and subsequent treatment with HBr/AcOEt (Iglesias-Arteaga et al., 1998) gave 25R-3β-bromo-5α-spirostan-6-one which was transformed into (25R)-23-acetyl-3β-bromo-16β-acetoxy-22,26-epoxy-5α-cholest-22-en-6-one using ZnCl2 instead of the previously described methodology (Castro-Méndez et al., 2002). Finally, the title compound was obtained by treatment of (25R)-23-acetyl-3β-bromo-16β-acetoxy-22,26-epoxy-5α-cholest-22-en-6-one (0.260 g, 0.493 mmol) with p-toluenesulfonic acid (0.260 g,1.36 mmol)in 0.7 ml toluene at 393 K for 30 minutes under vigorous stirring in a pressure tube. The solvent was evaporated under vacuum and the organic phase extracted with CH2Cl2-water, neutralized with NaHCO3 and dried over Na2SO4 to give a 0.160 g (61% yield) as white crystals which were purified by using a mixture of 70:30 hexane:ethyl acetate. (m.p. 468 – 470 K). Analysis calc.: C31H45O5Br: C 64.46, H 7.85, Br 13.85, O 13.85 %. Found: C 64.0, H 8.10 %. Block-like colourless crystals of the title compound, suitable for X-ray analysis, were grown by slow evaporation in a mixture of hexane:ethyl acetate (70:30) and a minimum quantity of CH2Cl2. Spectroscipic data for the title compound are given in the archived CIF.
All H atoms were placed in calculated positions and treated as riding atoms: C-H = 0.98, 0.97 and 0.96 Å for CH, CH2 and CH3 H atoms, respectively, with Uiso(H) = k × Ueq(C), where k = 1.5 for CH3 H atoms and = 1.2 for other H atoms.
Data collection: COLLECT (Nonius, 1999); cell
SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 2012).Fig. 1. A view of the molecular structure of the title compound, with the atom numbering. Displacement ellipsoids are drawn at 30% probability level. |
C31H45BrO5·CH2Cl2 | Dx = 1.406 Mg m−3 |
Mr = 662.51 | Melting point: 468(2) K |
Orthorhombic, P212121 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2ac 2ab | Cell parameters from 600 reflections |
a = 7.4423 (1) Å | θ = 3.5–28.7° |
b = 15.6578 (2) Å | µ = 1.52 mm−1 |
c = 26.8496 (3) Å | T = 293 K |
V = 3128.79 (7) Å3 | Block, colourless |
Z = 4 | 0.15 × 0.10 × 0.08 mm |
F(000) = 1392 |
Nonius KappaCCD diffractometer | 5668 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.088 |
Graphite monochromator | θmax = 28.7°, θmin = 3.5° |
Detector resolution: 9 pixels mm-1 | h = −9→9 |
ϕ and ω scans | k = −20→21 |
37310 measured reflections | l = −36→36 |
7934 independent reflections |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.068 | w = 1/[σ2(Fo2) + (0.087P)2 + 3.6522P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.181 | (Δ/σ)max < 0.001 |
S = 1.03 | Δρmax = 0.75 e Å−3 |
7934 reflections | Δρmin = −0.68 e Å−3 |
362 parameters | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
0 restraints | Extinction coefficient: 0.0038 (10) |
Primary atom site location: structure-invariant direct methods | Absolute structure: Flack (1983), 3453 Friedel pairs |
Secondary atom site location: difference Fourier map | Absolute structure parameter: 0.031 (13) |
C31H45BrO5·CH2Cl2 | V = 3128.79 (7) Å3 |
Mr = 662.51 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 7.4423 (1) Å | µ = 1.52 mm−1 |
b = 15.6578 (2) Å | T = 293 K |
c = 26.8496 (3) Å | 0.15 × 0.10 × 0.08 mm |
Nonius KappaCCD diffractometer | 5668 reflections with I > 2σ(I) |
37310 measured reflections | Rint = 0.088 |
7934 independent reflections |
R[F2 > 2σ(F2)] = 0.068 | H-atom parameters constrained |
wR(F2) = 0.181 | Δρmax = 0.75 e Å−3 |
S = 1.03 | Δρmin = −0.68 e Å−3 |
7934 reflections | Absolute structure: Flack (1983), 3453 Friedel pairs |
362 parameters | Absolute structure parameter: 0.031 (13) |
0 restraints |
Experimental. Spectroscopic data for the title compound: UV λmax 269 nm (ε 624); IR νmax cm-1(KBr): 2959 (CH), 1737 (OAc), 1711 (C═O), 1665 (C═O), 1452 (CH3), 1334 (CH), 1247 (C—O), 988 (C═ C), 710 (CH2), MS, m/z: (%): 578 ([M+], 1.4), 206 (18), 205 (32), 191 (10), 166 (10), 140 (15), 139 (100), 43 (59); 1H NMR (300 MHz, CDCl3) δ: 5.02 (1H, m, H-16), 4.09 (1H, d, J = 11.0 Hz, H-26), 3.94 (1H, m, H-3), 3.40 (1H, t, J = 10.0 Hz, H-26), 3.20 (1H, dq, J17–20 = 10.6 Hz, J20–21 = 6.94 Hz, H-20), 2.06 (3H, s, 3-OCOCH3), 2.14 (3H, s, 23''-CH3), 1.90 (3H, s, 16-OCOCH3),1.10 (3H, d, J = 6.9 Hz, CH3-27), 1.02 (3H, d, J = 6.1 Hz, CH3-21), 0.88 (3H, s, CH3-19), 0.81 (3H, s, CH3-18). 13C NMR (100 MHz, CDCl3) δ: 203.9 (22-CO), 169.8 (16-OCOCH3), 164.9 (C-23'), 59.1 (C-5), 209.3(C-6), 107.6 (C-23), 75.4 (C-16), 50.6 (C-3), 71.9 (C-26), 56.1 (C-17), 54.2 (C-14), 53.8 (C-9), 42.9 (C-13), 39.2 (C-12), 38.7 (C-20), 31.8 (C-4), 33.5 (C-1), 40.8 (C-10), 34.4 (C-15), 46.4 (C-7), 37.3 (C-8), 30.9 (C-24), 32.5 (C-2), 26.9 (C-25), 21.3 (16-OCOCH3), 21.5 (C-11), 21.0 (C-23''), 19.6 (C-19), 17.3 (C-21), 17.1 (C-27), 13.3 (C-18). |
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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. |
x | y | z | Uiso*/Ueq | ||
Br1 | 0.80129 (8) | 0.99071 (3) | 0.28226 (2) | 0.0514 (2) | |
O6 | 0.3019 (5) | 0.7718 (2) | 0.35688 (17) | 0.0616 (13) | |
O16 | 0.3802 (5) | 0.2944 (2) | 0.41187 (13) | 0.0429 (11) | |
O22 | 0.4244 (5) | 0.1706 (2) | 0.31163 (14) | 0.0531 (11) | |
O26 | 0.4238 (10) | −0.0251 (3) | 0.4188 (2) | 0.108 (3) | |
O30 | 0.0825 (6) | 0.2752 (3) | 0.41123 (19) | 0.0793 (18) | |
C1 | 0.8950 (6) | 0.7228 (3) | 0.29478 (19) | 0.0393 (14) | |
C2 | 0.9275 (7) | 0.8200 (3) | 0.2955 (2) | 0.0430 (14) | |
C3 | 0.7592 (6) | 0.8661 (3) | 0.27962 (19) | 0.0411 (13) | |
C4 | 0.5983 (7) | 0.8440 (3) | 0.3109 (2) | 0.0440 (16) | |
C5 | 0.5683 (6) | 0.7469 (3) | 0.31053 (17) | 0.0360 (12) | |
C6 | 0.4036 (7) | 0.7210 (3) | 0.3384 (2) | 0.0433 (14) | |
C7 | 0.3660 (6) | 0.6261 (3) | 0.3402 (2) | 0.0437 (14) | |
C8 | 0.5314 (6) | 0.5704 (3) | 0.35181 (18) | 0.0347 (12) | |
C9 | 0.6928 (6) | 0.5994 (3) | 0.31974 (16) | 0.0337 (11) | |
C10 | 0.7360 (6) | 0.6949 (3) | 0.32813 (16) | 0.0337 (12) | |
C11 | 0.8546 (6) | 0.5399 (3) | 0.3259 (2) | 0.0410 (14) | |
C12 | 0.8068 (7) | 0.4453 (3) | 0.31787 (19) | 0.0400 (14) | |
C13 | 0.6532 (5) | 0.4169 (3) | 0.35206 (16) | 0.0330 (12) | |
C14 | 0.4942 (6) | 0.4770 (3) | 0.34192 (18) | 0.0360 (12) | |
C15 | 0.3379 (6) | 0.4350 (3) | 0.3697 (2) | 0.0420 (14) | |
C16 | 0.3743 (6) | 0.3378 (3) | 0.36390 (17) | 0.0357 (12) | |
C17 | 0.5626 (6) | 0.3305 (3) | 0.33936 (17) | 0.0343 (12) | |
C18 | 0.7143 (7) | 0.4186 (3) | 0.40677 (18) | 0.0427 (14) | |
C19 | 0.7786 (8) | 0.7143 (3) | 0.38279 (18) | 0.0447 (16) | |
C20 | 0.6614 (6) | 0.2460 (3) | 0.35157 (18) | 0.0387 (14) | |
C21 | 0.8164 (7) | 0.2293 (3) | 0.3151 (2) | 0.0477 (16) | |
C22 | 0.5302 (7) | 0.1703 (3) | 0.34636 (18) | 0.0397 (14) | |
C23 | 0.5464 (8) | 0.1008 (3) | 0.3826 (2) | 0.0500 (18) | |
C23A | 0.4238 (10) | 0.0378 (4) | 0.3836 (2) | 0.065 (2) | |
C23B | 0.2656 (11) | 0.0256 (5) | 0.3511 (3) | 0.086 (3) | |
C24 | 0.7091 (12) | 0.0994 (3) | 0.4160 (2) | 0.071 (2) | |
C25 | 0.7367 (14) | 0.0126 (5) | 0.4400 (3) | 0.096 (3) | |
C26 | 0.5590 (18) | −0.0187 (6) | 0.4580 (3) | 0.118 (5) | |
C27 | 0.8847 (18) | 0.0162 (7) | 0.4812 (4) | 0.136 (5) | |
C30 | 0.2270 (7) | 0.2641 (3) | 0.4302 (2) | 0.0470 (17) | |
C31 | 0.2554 (9) | 0.2139 (4) | 0.4772 (2) | 0.0613 (19) | |
Cl1 | 0.6265 (19) | 0.2328 (4) | 0.0142 (2) | 0.431 (7) | |
Cl2 | 0.818 (2) | 0.3949 (7) | 0.0006 (3) | 0.398 (8) | |
C32 | 0.803 (4) | 0.3144 (11) | 0.0383 (7) | 0.268 (15) | |
H1A | 1.00321 | 0.69403 | 0.30591 | 0.0472* | |
H1B | 0.87157 | 0.70498 | 0.26080 | 0.0472* | |
H2A | 0.96114 | 0.83786 | 0.32883 | 0.0512* | |
H2B | 1.02524 | 0.83427 | 0.27310 | 0.0512* | |
H3 | 0.73308 | 0.85039 | 0.24504 | 0.0493* | |
H4A | 0.49272 | 0.87253 | 0.29774 | 0.0527* | |
H4B | 0.61698 | 0.86343 | 0.34475 | 0.0527* | |
H5 | 0.54770 | 0.73093 | 0.27571 | 0.0434* | |
H7A | 0.31708 | 0.60855 | 0.30826 | 0.0525* | |
H7B | 0.27497 | 0.61540 | 0.36525 | 0.0525* | |
H8 | 0.56241 | 0.57745 | 0.38705 | 0.0419* | |
H9 | 0.65452 | 0.59414 | 0.28495 | 0.0403* | |
H11A | 0.90383 | 0.54698 | 0.35904 | 0.0490* | |
H11B | 0.94678 | 0.55619 | 0.30214 | 0.0490* | |
H12A | 0.77192 | 0.43659 | 0.28344 | 0.0479* | |
H12B | 0.91193 | 0.41045 | 0.32438 | 0.0479* | |
H14 | 0.46691 | 0.47214 | 0.30632 | 0.0434* | |
H15A | 0.22363 | 0.45060 | 0.35490 | 0.0502* | |
H15B | 0.33747 | 0.45150 | 0.40454 | 0.0502* | |
H16 | 0.28301 | 0.31166 | 0.34246 | 0.0427* | |
H17 | 0.54264 | 0.33059 | 0.30329 | 0.0409* | |
H18A | 0.61701 | 0.40056 | 0.42778 | 0.0639* | |
H18B | 0.74936 | 0.47562 | 0.41564 | 0.0639* | |
H18C | 0.81448 | 0.38073 | 0.41106 | 0.0639* | |
H19A | 0.67965 | 0.69663 | 0.40329 | 0.0669* | |
H19B | 0.79785 | 0.77454 | 0.38681 | 0.0669* | |
H19C | 0.88495 | 0.68391 | 0.39254 | 0.0669* | |
H20 | 0.70800 | 0.24819 | 0.38568 | 0.0459* | |
H21A | 0.90162 | 0.27518 | 0.31709 | 0.0720* | |
H21B | 0.77002 | 0.22565 | 0.28182 | 0.0720* | |
H21C | 0.87455 | 0.17653 | 0.32364 | 0.0720* | |
H23A | 0.30428 | 0.02034 | 0.31711 | 0.1293* | |
H23B | 0.18680 | 0.07382 | 0.35421 | 0.1293* | |
H23C | 0.20303 | −0.02535 | 0.36083 | 0.1293* | |
H24A | 0.69499 | 0.14216 | 0.44181 | 0.0850* | |
H24B | 0.81472 | 0.11404 | 0.39661 | 0.0850* | |
H25 | 0.77821 | −0.02680 | 0.41402 | 0.1156* | |
H26A | 0.57485 | −0.07443 | 0.47309 | 0.1415* | |
H26B | 0.51536 | 0.01984 | 0.48356 | 0.1415* | |
H27A | 0.99494 | 0.03671 | 0.46697 | 0.2046* | |
H27B | 0.90312 | −0.03990 | 0.49463 | 0.2046* | |
H27C | 0.84698 | 0.05413 | 0.50726 | 0.2046* | |
H31A | 0.38116 | 0.21255 | 0.48510 | 0.0921* | |
H31B | 0.21244 | 0.15658 | 0.47259 | 0.0921* | |
H31C | 0.19064 | 0.24032 | 0.50403 | 0.0921* | |
H32A | 0.76877 | 0.33433 | 0.07112 | 0.3239* | |
H32B | 0.91948 | 0.28676 | 0.04100 | 0.3239* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br1 | 0.0619 (3) | 0.0273 (2) | 0.0649 (3) | −0.0021 (2) | −0.0020 (3) | 0.0035 (2) |
O6 | 0.046 (2) | 0.0369 (18) | 0.102 (3) | 0.0036 (19) | 0.017 (2) | −0.0094 (18) |
O16 | 0.0381 (17) | 0.0397 (18) | 0.051 (2) | −0.0033 (14) | 0.0011 (15) | 0.0094 (15) |
O22 | 0.066 (2) | 0.0364 (18) | 0.057 (2) | −0.0089 (18) | −0.018 (2) | 0.0031 (16) |
O26 | 0.160 (6) | 0.051 (3) | 0.114 (4) | −0.036 (3) | −0.010 (4) | 0.034 (3) |
O30 | 0.041 (2) | 0.101 (4) | 0.096 (3) | −0.006 (2) | −0.002 (2) | 0.044 (3) |
C1 | 0.033 (2) | 0.032 (2) | 0.053 (3) | −0.0008 (19) | 0.007 (2) | −0.0002 (19) |
C2 | 0.037 (2) | 0.036 (2) | 0.056 (3) | −0.008 (2) | 0.003 (2) | −0.001 (2) |
C3 | 0.050 (3) | 0.0244 (18) | 0.049 (2) | 0.0002 (16) | −0.007 (2) | −0.0020 (19) |
C4 | 0.044 (3) | 0.031 (2) | 0.057 (3) | 0.002 (2) | −0.007 (2) | 0.004 (2) |
C5 | 0.038 (2) | 0.029 (2) | 0.041 (2) | 0.0023 (19) | −0.007 (2) | −0.0004 (18) |
C6 | 0.034 (2) | 0.034 (2) | 0.062 (3) | 0.006 (2) | −0.006 (2) | −0.003 (2) |
C7 | 0.031 (2) | 0.036 (2) | 0.064 (3) | 0.0017 (19) | 0.001 (2) | 0.002 (2) |
C8 | 0.030 (2) | 0.034 (2) | 0.040 (2) | 0.0034 (18) | −0.0011 (19) | 0.0040 (19) |
C9 | 0.028 (2) | 0.0321 (19) | 0.041 (2) | −0.003 (2) | −0.004 (2) | 0.0025 (16) |
C10 | 0.029 (2) | 0.032 (2) | 0.040 (2) | −0.0030 (16) | −0.0012 (17) | 0.0006 (17) |
C11 | 0.029 (2) | 0.033 (2) | 0.061 (3) | 0.0011 (17) | 0.005 (2) | 0.003 (2) |
C12 | 0.029 (2) | 0.032 (2) | 0.059 (3) | −0.002 (2) | 0.005 (2) | 0.0023 (18) |
C13 | 0.028 (2) | 0.031 (2) | 0.040 (2) | 0.0033 (16) | 0.0020 (18) | 0.0032 (17) |
C14 | 0.032 (2) | 0.034 (2) | 0.042 (2) | 0.0021 (18) | −0.0021 (19) | 0.0067 (19) |
C15 | 0.033 (2) | 0.035 (2) | 0.058 (3) | 0.0007 (19) | 0.003 (2) | 0.009 (2) |
C16 | 0.032 (2) | 0.032 (2) | 0.043 (2) | −0.0039 (18) | −0.0040 (19) | 0.0086 (18) |
C17 | 0.032 (2) | 0.030 (2) | 0.041 (2) | −0.0015 (18) | −0.0055 (19) | 0.0051 (18) |
C18 | 0.040 (2) | 0.038 (2) | 0.050 (3) | 0.002 (2) | −0.012 (2) | 0.0044 (19) |
C19 | 0.046 (3) | 0.038 (2) | 0.050 (3) | 0.001 (2) | −0.005 (2) | −0.0005 (19) |
C20 | 0.034 (2) | 0.031 (2) | 0.051 (3) | −0.0049 (18) | −0.003 (2) | 0.0046 (18) |
C21 | 0.041 (3) | 0.033 (2) | 0.069 (3) | 0.004 (2) | 0.002 (3) | 0.001 (2) |
C22 | 0.046 (3) | 0.032 (2) | 0.041 (2) | 0.001 (2) | −0.003 (2) | −0.0031 (19) |
C23 | 0.071 (4) | 0.029 (2) | 0.050 (3) | −0.001 (2) | −0.001 (3) | 0.003 (2) |
C23A | 0.092 (5) | 0.039 (3) | 0.063 (4) | −0.015 (3) | 0.006 (4) | 0.000 (2) |
C23B | 0.083 (5) | 0.057 (4) | 0.119 (6) | −0.034 (3) | −0.003 (4) | 0.007 (4) |
C24 | 0.111 (5) | 0.035 (3) | 0.066 (3) | −0.009 (4) | −0.026 (4) | 0.010 (2) |
C25 | 0.135 (7) | 0.056 (4) | 0.098 (5) | −0.005 (5) | −0.048 (5) | 0.025 (4) |
C26 | 0.209 (12) | 0.062 (5) | 0.083 (5) | −0.015 (6) | −0.053 (7) | 0.033 (4) |
C27 | 0.188 (11) | 0.085 (6) | 0.136 (8) | −0.008 (7) | −0.084 (8) | 0.048 (6) |
C30 | 0.035 (3) | 0.045 (3) | 0.061 (3) | 0.002 (2) | 0.006 (2) | 0.008 (2) |
C31 | 0.072 (4) | 0.054 (3) | 0.058 (3) | 0.000 (3) | 0.012 (3) | 0.021 (3) |
Cl1 | 0.87 (2) | 0.186 (5) | 0.237 (6) | −0.123 (9) | 0.347 (11) | −0.054 (4) |
Cl2 | 0.547 (19) | 0.378 (12) | 0.269 (8) | 0.110 (13) | 0.089 (11) | 0.049 (8) |
C32 | 0.46 (4) | 0.134 (13) | 0.211 (16) | 0.07 (2) | 0.07 (2) | 0.087 (13) |
Br1—C3 | 1.977 (5) | C2—H2B | 0.9700 |
Cl1—C32 | 1.94 (3) | C2—H2A | 0.9700 |
Cl2—C32 | 1.62 (2) | C3—H3 | 0.9800 |
O6—C6 | 1.205 (6) | C4—H4B | 0.9700 |
O16—C30 | 1.329 (6) | C4—H4A | 0.9700 |
O16—C16 | 1.457 (6) | C5—H5 | 0.9800 |
O22—C22 | 1.221 (6) | C7—H7B | 0.9700 |
O26—C23A | 1.365 (8) | C7—H7A | 0.9700 |
O26—C26 | 1.460 (13) | C8—H8 | 0.9800 |
O30—C30 | 1.203 (7) | C9—H9 | 0.9800 |
C1—C10 | 1.547 (6) | C11—H11B | 0.9700 |
C1—C2 | 1.541 (7) | C11—H11A | 0.9700 |
C2—C3 | 1.507 (7) | C12—H12B | 0.9700 |
C3—C4 | 1.503 (7) | C12—H12A | 0.9700 |
C4—C5 | 1.537 (7) | C14—H14 | 0.9800 |
C5—C6 | 1.492 (7) | C15—H15B | 0.9700 |
C5—C10 | 1.563 (6) | C15—H15A | 0.9700 |
C6—C7 | 1.513 (7) | C16—H16 | 0.9800 |
C7—C8 | 1.541 (6) | C17—H17 | 0.9800 |
C8—C14 | 1.512 (7) | C18—H18B | 0.9600 |
C8—C9 | 1.546 (6) | C18—H18A | 0.9600 |
C9—C10 | 1.546 (7) | C18—H18C | 0.9600 |
C9—C11 | 1.531 (6) | C19—H19B | 0.9600 |
C10—C19 | 1.532 (7) | C19—H19C | 0.9600 |
C11—C12 | 1.539 (7) | C19—H19A | 0.9600 |
C12—C13 | 1.532 (7) | C20—H20 | 0.9800 |
C13—C18 | 1.538 (6) | C21—H21B | 0.9600 |
C13—C14 | 1.536 (6) | C21—H21A | 0.9600 |
C13—C17 | 1.550 (6) | C21—H21C | 0.9600 |
C14—C15 | 1.530 (7) | C23B—H23C | 0.9600 |
C15—C16 | 1.554 (7) | C23B—H23B | 0.9600 |
C16—C17 | 1.553 (6) | C23B—H23A | 0.9600 |
C17—C20 | 1.549 (7) | C24—H24A | 0.9700 |
C20—C22 | 1.542 (7) | C24—H24B | 0.9700 |
C20—C21 | 1.536 (7) | C25—H25 | 0.9800 |
C22—C23 | 1.465 (7) | C26—H26A | 0.9700 |
C23—C24 | 1.507 (10) | C26—H26B | 0.9700 |
C23—C23A | 1.344 (9) | C27—H27B | 0.9600 |
C23A—C23B | 1.478 (11) | C27—H27C | 0.9600 |
C24—C25 | 1.518 (9) | C27—H27A | 0.9600 |
C25—C27 | 1.562 (15) | C31—H31C | 0.9600 |
C25—C26 | 1.491 (16) | C31—H31A | 0.9600 |
C30—C31 | 1.502 (8) | C31—H31B | 0.9600 |
C1—H1A | 0.9700 | C32—H32A | 0.9700 |
C1—H1B | 0.9700 | C32—H32B | 0.9700 |
C16—O16—C30 | 117.9 (4) | H7A—C7—H7B | 108.00 |
C23A—O26—C26 | 116.7 (6) | C7—C8—H8 | 109.00 |
C2—C1—C10 | 113.1 (4) | C9—C8—H8 | 109.00 |
C1—C2—C3 | 109.8 (4) | C14—C8—H8 | 109.00 |
Br1—C3—C2 | 109.3 (3) | C8—C9—H9 | 106.00 |
Br1—C3—C4 | 109.5 (3) | C10—C9—H9 | 106.00 |
C2—C3—C4 | 113.2 (4) | C11—C9—H9 | 106.00 |
C3—C4—C5 | 109.9 (4) | C9—C11—H11A | 109.00 |
C4—C5—C6 | 112.6 (4) | C9—C11—H11B | 109.00 |
C4—C5—C10 | 113.4 (4) | C12—C11—H11A | 109.00 |
C6—C5—C10 | 111.3 (4) | C12—C11—H11B | 109.00 |
O6—C6—C5 | 122.9 (4) | H11A—C11—H11B | 108.00 |
O6—C6—C7 | 121.3 (5) | C11—C12—H12A | 109.00 |
C5—C6—C7 | 115.8 (4) | C11—C12—H12B | 109.00 |
C6—C7—C8 | 114.5 (4) | C13—C12—H12A | 109.00 |
C7—C8—C9 | 110.0 (4) | C13—C12—H12B | 109.00 |
C7—C8—C14 | 111.5 (4) | H12A—C12—H12B | 108.00 |
C9—C8—C14 | 109.2 (4) | C8—C14—H14 | 107.00 |
C8—C9—C10 | 111.4 (4) | C13—C14—H14 | 107.00 |
C8—C9—C11 | 111.8 (4) | C15—C14—H14 | 107.00 |
C10—C9—C11 | 114.2 (4) | C14—C15—H15A | 111.00 |
C1—C10—C5 | 106.8 (4) | C14—C15—H15B | 111.00 |
C1—C10—C9 | 110.4 (4) | C16—C15—H15A | 111.00 |
C1—C10—C19 | 109.9 (4) | C16—C15—H15B | 111.00 |
C5—C10—C9 | 107.1 (4) | H15A—C15—H15B | 109.00 |
C5—C10—C19 | 110.6 (4) | O16—C16—H16 | 110.00 |
C9—C10—C19 | 112.0 (4) | C15—C16—H16 | 110.00 |
C9—C11—C12 | 112.9 (4) | C17—C16—H16 | 110.00 |
C11—C12—C13 | 111.6 (4) | C13—C17—H17 | 106.00 |
C12—C13—C14 | 106.9 (4) | C16—C17—H17 | 106.00 |
C12—C13—C17 | 116.5 (4) | C20—C17—H17 | 106.00 |
C12—C13—C18 | 110.3 (4) | C13—C18—H18A | 109.00 |
C14—C13—C17 | 99.2 (3) | C13—C18—H18B | 109.00 |
C14—C13—C18 | 112.7 (4) | C13—C18—H18C | 109.00 |
C17—C13—C18 | 110.7 (4) | H18A—C18—H18B | 109.00 |
C8—C14—C13 | 114.9 (4) | H18A—C18—H18C | 109.00 |
C8—C14—C15 | 118.0 (4) | H18B—C18—H18C | 109.00 |
C13—C14—C15 | 103.6 (4) | C10—C19—H19A | 109.00 |
C14—C15—C16 | 103.9 (4) | C10—C19—H19B | 109.00 |
O16—C16—C15 | 111.9 (4) | C10—C19—H19C | 109.00 |
O16—C16—C17 | 108.3 (4) | H19A—C19—H19B | 109.00 |
C15—C16—C17 | 105.8 (4) | H19A—C19—H19C | 109.00 |
C13—C17—C16 | 103.6 (4) | H19B—C19—H19C | 109.00 |
C13—C17—C20 | 119.5 (4) | C17—C20—H20 | 110.00 |
C16—C17—C20 | 113.7 (4) | C21—C20—H20 | 110.00 |
C17—C20—C21 | 111.5 (4) | C22—C20—H20 | 110.00 |
C17—C20—C22 | 109.7 (4) | C20—C21—H21A | 109.00 |
C21—C20—C22 | 106.7 (4) | C20—C21—H21B | 109.00 |
O22—C22—C20 | 118.4 (4) | C20—C21—H21C | 109.00 |
O22—C22—C23 | 124.3 (5) | H21A—C21—H21B | 110.00 |
C20—C22—C23 | 117.3 (4) | H21A—C21—H21C | 109.00 |
C22—C23—C23A | 120.2 (5) | H21B—C21—H21C | 109.00 |
C22—C23—C24 | 118.2 (5) | C23A—C23B—H23A | 109.00 |
C23A—C23—C24 | 121.5 (5) | C23A—C23B—H23B | 109.00 |
O26—C23A—C23 | 122.9 (6) | C23A—C23B—H23C | 109.00 |
O26—C23A—C23B | 108.4 (6) | H23A—C23B—H23B | 109.00 |
C23—C23A—C23B | 128.6 (6) | H23A—C23B—H23C | 109.00 |
C23—C24—C25 | 112.0 (6) | H23B—C23B—H23C | 109.00 |
C24—C25—C26 | 108.2 (8) | C23—C24—H24A | 109.00 |
C24—C25—C27 | 111.3 (7) | C23—C24—H24B | 109.00 |
C26—C25—C27 | 114.1 (8) | C25—C24—H24A | 109.00 |
O26—C26—C25 | 113.6 (7) | C25—C24—H24B | 109.00 |
O16—C30—O30 | 124.0 (5) | H24A—C24—H24B | 108.00 |
O16—C30—C31 | 112.2 (5) | C24—C25—H25 | 108.00 |
O30—C30—C31 | 123.9 (5) | C26—C25—H25 | 108.00 |
C2—C1—H1A | 109.00 | C27—C25—H25 | 108.00 |
C2—C1—H1B | 109.00 | O26—C26—H26A | 109.00 |
C10—C1—H1A | 109.00 | O26—C26—H26B | 109.00 |
C10—C1—H1B | 109.00 | C25—C26—H26A | 109.00 |
H1A—C1—H1B | 108.00 | C25—C26—H26B | 109.00 |
C1—C2—H2A | 110.00 | H26A—C26—H26B | 108.00 |
C1—C2—H2B | 110.00 | C25—C27—H27A | 109.00 |
C3—C2—H2A | 110.00 | C25—C27—H27B | 110.00 |
C3—C2—H2B | 110.00 | C25—C27—H27C | 109.00 |
H2A—C2—H2B | 108.00 | H27A—C27—H27B | 109.00 |
Br1—C3—H3 | 108.00 | H27A—C27—H27C | 109.00 |
C2—C3—H3 | 108.00 | H27B—C27—H27C | 110.00 |
C4—C3—H3 | 108.00 | C30—C31—H31A | 110.00 |
C3—C4—H4A | 110.00 | C30—C31—H31B | 110.00 |
C3—C4—H4B | 110.00 | C30—C31—H31C | 110.00 |
C5—C4—H4A | 110.00 | H31A—C31—H31B | 109.00 |
C5—C4—H4B | 110.00 | H31A—C31—H31C | 109.00 |
H4A—C4—H4B | 108.00 | H31B—C31—H31C | 109.00 |
C4—C5—H5 | 106.00 | Cl1—C32—Cl2 | 110.5 (13) |
C6—C5—H5 | 106.00 | Cl1—C32—H32A | 110.00 |
C10—C5—H5 | 106.00 | Cl1—C32—H32B | 110.00 |
C6—C7—H7A | 109.00 | Cl2—C32—H32A | 110.00 |
C6—C7—H7B | 109.00 | Cl2—C32—H32B | 109.00 |
C8—C7—H7A | 109.00 | H32A—C32—H32B | 108.00 |
C8—C7—H7B | 109.00 | ||
C30—O16—C16—C17 | −154.6 (4) | C9—C11—C12—C13 | −55.2 (5) |
C30—O16—C16—C15 | 89.2 (5) | C11—C12—C13—C17 | 166.1 (4) |
C16—O16—C30—O30 | −5.1 (7) | C11—C12—C13—C18 | −66.6 (5) |
C16—O16—C30—C31 | 174.6 (4) | C11—C12—C13—C14 | 56.3 (5) |
C23A—O26—C26—C25 | −38.4 (10) | C18—C13—C14—C8 | 61.4 (5) |
C26—O26—C23A—C23B | −173.4 (7) | C18—C13—C14—C15 | −68.8 (5) |
C26—O26—C23A—C23 | 3.5 (10) | C12—C13—C17—C16 | −157.1 (4) |
C2—C1—C10—C19 | −64.4 (5) | C12—C13—C17—C20 | 75.2 (5) |
C2—C1—C10—C9 | 171.6 (4) | C14—C13—C17—C16 | −42.9 (4) |
C10—C1—C2—C3 | −57.2 (5) | C18—C13—C17—C16 | 75.8 (4) |
C2—C1—C10—C5 | 55.6 (5) | C12—C13—C14—C15 | 169.9 (4) |
C1—C2—C3—Br1 | 178.7 (3) | C18—C13—C17—C20 | −51.9 (5) |
C1—C2—C3—C4 | 56.4 (6) | C12—C13—C14—C8 | −60.0 (5) |
C2—C3—C4—C5 | −55.9 (5) | C14—C13—C17—C20 | −170.6 (4) |
Br1—C3—C4—C5 | −178.1 (3) | C17—C13—C14—C8 | 178.6 (4) |
C3—C4—C5—C10 | 56.0 (5) | C17—C13—C14—C15 | 48.4 (4) |
C3—C4—C5—C6 | −176.5 (4) | C13—C14—C15—C16 | −35.0 (5) |
C4—C5—C6—C7 | −179.4 (4) | C8—C14—C15—C16 | −163.2 (4) |
C6—C5—C10—C1 | 176.6 (4) | C14—C15—C16—O16 | 125.2 (4) |
C4—C5—C6—O6 | 3.4 (7) | C14—C15—C16—C17 | 7.5 (5) |
C10—C5—C6—O6 | 132.0 (5) | C15—C16—C17—C13 | 22.3 (4) |
C6—C5—C10—C9 | 58.4 (5) | C15—C16—C17—C20 | 153.6 (4) |
C6—C5—C10—C19 | −63.9 (5) | O16—C16—C17—C20 | 33.4 (5) |
C4—C5—C10—C19 | 64.3 (5) | O16—C16—C17—C13 | −97.8 (4) |
C4—C5—C10—C9 | −173.4 (4) | C13—C17—C20—C21 | −74.3 (5) |
C10—C5—C6—C7 | −50.7 (6) | C16—C17—C20—C21 | 162.8 (4) |
C4—C5—C10—C1 | −55.2 (5) | C13—C17—C20—C22 | 167.7 (4) |
O6—C6—C7—C8 | −137.9 (5) | C16—C17—C20—C22 | 44.8 (5) |
C5—C6—C7—C8 | 44.8 (6) | C17—C20—C22—C23 | −142.1 (4) |
C6—C7—C8—C9 | −46.2 (6) | C21—C20—C22—C23 | 97.0 (5) |
C6—C7—C8—C14 | −167.5 (4) | C21—C20—C22—O22 | −80.6 (5) |
C7—C8—C9—C11 | −173.9 (4) | C17—C20—C22—O22 | 40.4 (6) |
C14—C8—C9—C10 | 179.6 (4) | O22—C22—C23—C23A | −10.1 (8) |
C7—C8—C14—C13 | 179.4 (4) | C20—C22—C23—C24 | −11.3 (7) |
C14—C8—C9—C11 | −51.3 (5) | O22—C22—C23—C24 | 166.2 (5) |
C7—C8—C14—C15 | −57.9 (6) | C20—C22—C23—C23A | 172.5 (5) |
C7—C8—C9—C10 | 57.0 (5) | C24—C23—C23A—O26 | 9.0 (9) |
C9—C8—C14—C13 | 57.7 (5) | C24—C23—C23A—C23B | −174.8 (6) |
C9—C8—C14—C15 | −179.6 (4) | C22—C23—C23A—C23B | 1.3 (10) |
C11—C9—C10—C1 | 53.5 (5) | C22—C23—C23A—O26 | −174.9 (6) |
C8—C9—C10—C19 | 58.5 (5) | C23A—C23—C24—C25 | 13.2 (9) |
C11—C9—C10—C19 | −69.3 (5) | C22—C23—C24—C25 | −163.0 (6) |
C11—C9—C10—C5 | 169.3 (4) | C23—C24—C25—C26 | −44.2 (8) |
C8—C9—C10—C5 | −62.9 (4) | C23—C24—C25—C27 | −170.3 (7) |
C8—C9—C10—C1 | −178.7 (4) | C24—C25—C26—O26 | 57.9 (9) |
C10—C9—C11—C12 | 179.4 (4) | C27—C25—C26—O26 | −177.7 (7) |
C8—C9—C11—C12 | 51.8 (5) |
D—H···A | D—H | H···A | D···A | D—H···A |
C5—H5···O22i | 0.98 | 2.54 | 3.491 (6) | 165 |
C18—H18C···O30ii | 0.96 | 2.59 | 3.545 (7) | 173 |
C27—H27B···Cl2iii | 0.96 | 2.32 | 2.957 (18) | 124 |
C32—H32A···O6iv | 0.97 | 2.23 | 3.00 (2) | 135 |
C32—H32B···Cl1v | 0.97 | 2.16 | 2.89 (3) | 130 |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) x+1, y, z; (iii) −x+2, y−1/2, −z+1/2; (iv) −x+1, y−1/2, −z+1/2; (v) x+1/2, −y+1/2, −z. |
Experimental details
Crystal data | |
Chemical formula | C31H45BrO5·CH2Cl2 |
Mr | 662.51 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 293 |
a, b, c (Å) | 7.4423 (1), 15.6578 (2), 26.8496 (3) |
V (Å3) | 3128.79 (7) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 1.52 |
Crystal size (mm) | 0.15 × 0.10 × 0.08 |
Data collection | |
Diffractometer | Nonius KappaCCD diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 37310, 7934, 5668 |
Rint | 0.088 |
(sin θ/λ)max (Å−1) | 0.676 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.068, 0.181, 1.03 |
No. of reflections | 7934 |
No. of parameters | 362 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.75, −0.68 |
Absolute structure | Flack (1983), 3453 Friedel pairs |
Absolute structure parameter | 0.031 (13) |
Computer programs: COLLECT (Nonius, 1999), DENZO and SCALEPACK (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009), WinGX (Farrugia, 2012).
D—H···A | D—H | H···A | D···A | D—H···A |
C5—H5···O22i | 0.98 | 2.54 | 3.491 (6) | 165 |
C18—H18C···O30ii | 0.96 | 2.59 | 3.545 (7) | 173 |
C27—H27B···Cl2iii | 0.96 | 2.32 | 2.957 (18) | 124 |
C32—H32A···O6iv | 0.97 | 2.23 | 3.00 (2) | 135 |
C32—H32B···Cl1v | 0.97 | 2.16 | 2.89 (3) | 130 |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) x+1, y, z; (iii) −x+2, y−1/2, −z+1/2; (iv) −x+1, y−1/2, −z+1/2; (v) x+1/2, −y+1/2, −z. |
Acknowledgements
The authors thank CONACYT for financial support and the Consejo Superior de la Investigación Científica in Spain for the award of a license for the use of the Cambridge Structural Database. Thanks are due to Marco A. Leyva-Ramírez (CINVESTAV-IPN) for helpful discussions.
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Steroidal saponins are plant metabolites with a broad range of biological activities (Hostettmann & Marston, 1995). They are composed by a glycoside and a triterpene or steroidal fragment. Hydrolysis of saponins provides a glycoside free portion termed sapogenin which can be of the cholestane, furostane or spirostane type. The spirostane sapogenins also display economic importance due to their application in the synthesis of biologically active compounds such as insect hormones (Lee et al., 1976) cephalostatins and ritterazines (Lee et al., 2009, Phillips & Shair, 2007 and Pettit et al., 1988). In previous studies we reported the preparation of epoxycholestane derivatives as useful intermediates in the synthesis of norbrassinosteroid analogues (Rincón et al., 2006), in continuation with our studies we report herein on the synthesis and crystal structure of the title compound, (I), obtained by treatment of the previously reported (25R)-23-acetyl-3β-bromo-16β-acetoxy-22,26-epoxy-5α-cholest-22-en-6-one(Castro-Méndez et al., 2002) with p-toluenesulfonic acid. In turn, the 22,26-epoxy-5α-cholestanic derivative was obtained in five steps using a modified procedure of the reported methodology (Castro-Méndez et al., 2002).
The title compound is interesting because it is a useful intermediate to introduce functionality at the 2 and 3 positions of brassinosteroid analogues. The X-ray crystal structure analysis showed that the configuration at the stereogenic centers C20S and C25R are retained (Fig. 1). The steroid nucleus shows that the A/B, B/C and C/D rings junctions are trans. The presence of the bromine bonded to C3 does not disturb the chair conformation of the A ring [puckering parameters for ring (C1—C5/C10) are Q = 0.576 (5) Å, θ = 2.2 (5)°, ϕ = 323 (20)°; Cremer & Pople, 1975 ]. Ring B assumes an almost perfect chair conformation which contains a carbonyl group at C5 [puckering parameters: Q = 0.565 (5) Å, θ = 14.0 (5)°,ϕ = 278 (2)°, if the calculation starts from C5 to C10 and proceeds in counterclockwise direction]. The same chair conformation was observed for the C ring [puckering parameters (C8/C9/C11—C14) Q = 0.570 (5) Å, θ = 4.8 (5)°, ϕ = 251 (6)°]. The five-membered D ring has an envelope conformation with atom C13 as the flap [puckering parameters (C13/C14/C15/C16/C17) q2 = 0.480 (5) Å and ϕ2 = 188.7 (6)°]. The six-membered dihydropyran E ring adopts a twisted-boat conformation [puckering parameters (O26/C23A/C23—C26) Q = 0.472 (10) Å, θ = 122.8 (10)°, ϕ = 79.5 (11)°].
The bond distances for C6—O6 and C23—C23A are 1.205 (6) Å and 1.344 (9) Å, respectively, confirming the existence of a double bond. The C3—Br1 bond distance is 1.977 (5) Å being slightly longer than the average values reported for Br—C*= 1.966 (29) (Allen et al., 1987) and C3—Br1 = 1.966 (5) Å in a related steroidal compound containing bromine in the same position (Castro-Méndez et al., 2002). The bromine at position three is equatorial and antiperiplanar to the C4—C5 bond with a torsion angle -178.1 (3). The bond distances for C23A—O26 and C26—O26 are 1.365 (8) Å and 1.460 (13) Å, respectively (Table 1); these values are in the range reported for bond distances in a similar compound, that is the cholestane derivative from diosgenin [C22—O26, 1.365 (5) Å and C26—O26 1.441 (5) Å; Castro-Méndez et al., 2002] and are in the average range reported for Csp2—O(2) in enol ethers C═ C—O—C*= 1.354 (16) Å and Csp3—O(2) in tetrahydropyran 1.441 (15) Å (Allen et al., 1987).
In the crystal, molecules are linked by C—H···O and C—H···Cl hydrogen bonds (Table 1), the latter involve the dichloromethane solvent molecule, forming a three-dimensional supramolecular architecture.