Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807055110/pk2059sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807055110/pk2059Isup2.hkl |
CCDC reference: 672861
Key indicators
- Single-crystal X-ray study
- T = 153 K
- Mean (C-C) = 0.003 Å
- Disorder in main residue
- R factor = 0.037
- wR factor = 0.094
- Data-to-parameter ratio = 7.3
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical . ? PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax .LT. 18) ..... 7.26 PLAT301_ALERT_3_C Main Residue Disorder ......................... 6.00 Perc. PLAT366_ALERT_2_C Short? C(sp?)-C(sp?) Bond C20 - C21 ... 1.38 Ang.
Alert level G REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is correct. If it is not, please give the correct count in the _publ_section_exptl_refinement section of the submitted CIF. From the CIF: _diffrn_reflns_theta_max 25.05 From the CIF: _reflns_number_total 2222 Count of symmetry unique reflns 2266 Completeness (_total/calc) 98.06% TEST3: Check Friedels for noncentro structure Estimate of Friedel pairs measured 0 Fraction of Friedel pairs measured 0.000 Are heavy atom types Z>Si present no PLAT791_ALERT_1_G Confirm the Absolute Configuration of C1 = . S PLAT791_ALERT_1_G Confirm the Absolute Configuration of C3 = . R PLAT791_ALERT_1_G Confirm the Absolute Configuration of C5 = . R PLAT791_ALERT_1_G Confirm the Absolute Configuration of C7 = . R PLAT791_ALERT_1_G Confirm the Absolute Configuration of C8 = . S PLAT791_ALERT_1_G Confirm the Absolute Configuration of C9 = . R PLAT791_ALERT_1_G Confirm the Absolute Configuration of C10 = . S PLAT791_ALERT_1_G Confirm the Absolute Configuration of C13 = . S PLAT791_ALERT_1_G Confirm the Absolute Configuration of C14 = . S PLAT791_ALERT_1_G Confirm the Absolute Configuration of C15 = . S PLAT791_ALERT_1_G Confirm the Absolute Configuration of C17 = . S
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 4 ALERT level C = Check and explain 12 ALERT level G = General alerts; check 12 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 1 ALERT type 2 Indicator that the structure model may be wrong or deficient 2 ALERT type 3 Indicator that the structure quality may be low 1 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
Air-dried and powdered barks of Khaya senegalensis (3.8 kg) were extracted with 95% alcohol at room temperature. The EtOH extract was dried under reduced pressure to yield a crude extract (310 g). The crude extract was suspended in 1000 ml water and partitioned with 2000 ml trichloromethane to yield a CHCl3 fraction (45 g). This part was separated by chromatography on silica gel, eluting with mixtures of hexane and acetone (increasing polarity). The purified powder (30 mg) of the title compound was obtained from the hexane:acetone (3:1) fractions. Transparent rod shaped crystals of the title compound were obtained by recrystallization from 5% CHCl3 in MeOH by slow evaporation at room temperature.
Since the most electron-rich atom is oxygen it was not possible to determine the absolute configuation using MoKα radiation. Therefore, Friedel pairs were merged before the final refinement because of the absence of significant anomalous scattering. All H atoms were placed geometrically and allowed to ride on the corresponding non-H atom with C—H = 0.96 Å, O—H = 0.83 Å, and Uiso(H) = 1.5Ueq of the attached atom for methyl and hydroxyl H atoms and 1.2Ueq(C) for other H atoms.
Data collection: CrystalClear (Rigaku/MSC, 2006); cell refinement: CrystalClear (Rigaku/MSC, 2006); data reduction: SHELXTL (Bruker, 2000); program(s) used to solve structure: SHELXTL (Bruker, 2000); program(s) used to refine structure: SHELXTL (Bruker, 2000); molecular graphics: SHELXTL (Bruker, 2000); software used to prepare material for publication: PLATON (Spek, 2003).
Fig. 1. view of the title compound, showing 50% probability displacement and the atom-numbering scheme |
C26H36O7 | F(000) = 992 |
Mr = 460.55 | Dx = 1.363 Mg m−3 |
Orthorhombic, P212121 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2ac 2ab | Cell parameters from 8564 reflections |
a = 9.856 (2) Å | θ = 4.2–26.4° |
b = 14.492 (3) Å | µ = 0.10 mm−1 |
c = 15.714 (3) Å | T = 153 K |
V = 2244.5 (8) Å3 | Block, colourless |
Z = 4 | 0.41 × 0.41 × 0.31 mm |
Riguka Mercury CCD diffractometer | 2222 independent reflections |
Radiation source: sealed tube | 2133 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.037 |
ω scans | θmax = 25.1°, θmin = 3.3° |
Absorption correction: multi-scan (Rigaku/MSC, 2006) | h = −8→11 |
Tmin = 0.961, Tmax = 0.970 | k = −17→17 |
16840 measured reflections | l = −18→18 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.037 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.094 | H-atom parameters constrained |
S = 1.07 | w = 1/[σ2(Fo2) + (0.063P)2 + 0.9576P] where P = (Fo2 + 2Fc2)/3 |
2222 reflections | (Δ/σ)max < 0.001 |
306 parameters | Δρmax = 0.19 e Å−3 |
0 restraints | Δρmin = −0.16 e Å−3 |
C26H36O7 | V = 2244.5 (8) Å3 |
Mr = 460.55 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 9.856 (2) Å | µ = 0.10 mm−1 |
b = 14.492 (3) Å | T = 153 K |
c = 15.714 (3) Å | 0.41 × 0.41 × 0.31 mm |
Riguka Mercury CCD diffractometer | 2222 independent reflections |
Absorption correction: multi-scan (Rigaku/MSC, 2006) | 2133 reflections with I > 2σ(I) |
Tmin = 0.961, Tmax = 0.970 | Rint = 0.037 |
16840 measured reflections |
R[F2 > 2σ(F2)] = 0.037 | 0 restraints |
wR(F2) = 0.094 | H-atom parameters constrained |
S = 1.07 | Δρmax = 0.19 e Å−3 |
2222 reflections | Δρmin = −0.16 e Å−3 |
306 parameters |
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 > 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 | Occ. (<1) | |
O1 | 0.54360 (19) | 0.79446 (11) | 0.30374 (11) | 0.0253 (4) | |
H1A | 0.6098 | 0.8242 | 0.2860 | 0.038* | |
O3 | 0.5683 (2) | 0.75585 (12) | 0.47596 (10) | 0.0283 (4) | |
H3A | 0.5492 | 0.7884 | 0.4342 | 0.042* | |
O4 | 0.10161 (19) | 0.74230 (12) | 0.34713 (10) | 0.0251 (4) | |
H4 | 0.0843 | 0.7394 | 0.3987 | 0.038* | |
O5 | −0.01398 (18) | 0.68425 (11) | 0.12115 (11) | 0.0248 (4) | |
O6 | −0.06666 (17) | 0.87686 (12) | 0.09534 (11) | 0.0262 (4) | |
O7 | −0.22403 (19) | 0.85936 (13) | 0.19420 (13) | 0.0328 (4) | |
O8 | 0.2139 (2) | 0.99496 (16) | −0.10650 (13) | 0.0320 (5) | 0.50 |
C23' | 0.2139 (2) | 0.99496 (16) | −0.10650 (13) | 0.0320 (5) | 0.50 |
H23' | 0.2700 | 1.0078 | −0.1550 | 0.038* | 0.50 |
C1 | 0.5671 (3) | 0.69684 (16) | 0.29037 (15) | 0.0222 (5) | |
H1 | 0.6137 | 0.6891 | 0.2372 | 0.027* | |
C2 | 0.6585 (3) | 0.66042 (19) | 0.36194 (15) | 0.0257 (5) | |
H2A | 0.6850 | 0.5983 | 0.3489 | 0.031* | |
H2B | 0.7393 | 0.6973 | 0.3645 | 0.031* | |
C3 | 0.5893 (3) | 0.66186 (17) | 0.44869 (15) | 0.0238 (5) | |
H3 | 0.6498 | 0.6333 | 0.4887 | 0.029* | |
C4 | 0.4551 (3) | 0.60729 (16) | 0.45018 (15) | 0.0216 (5) | |
C5 | 0.3648 (2) | 0.64328 (15) | 0.37633 (14) | 0.0184 (5) | |
H5 | 0.3485 | 0.7070 | 0.3896 | 0.022* | |
C6 | 0.2239 (3) | 0.59939 (16) | 0.37310 (15) | 0.0214 (5) | |
H6A | 0.2321 | 0.5369 | 0.3535 | 0.026* | |
H6B | 0.1867 | 0.5978 | 0.4295 | 0.026* | |
C7 | 0.1268 (2) | 0.65128 (16) | 0.31494 (15) | 0.0205 (5) | |
H7 | 0.0423 | 0.6183 | 0.3130 | 0.025* | |
C8 | 0.1815 (2) | 0.66078 (15) | 0.22338 (14) | 0.0190 (5) | |
C9 | 0.3285 (2) | 0.69989 (16) | 0.22822 (14) | 0.0192 (5) | |
H9 | 0.3191 | 0.7586 | 0.2560 | 0.023* | |
C10 | 0.4298 (2) | 0.64452 (16) | 0.28547 (14) | 0.0199 (5) | |
C11 | 0.3866 (3) | 0.72283 (18) | 0.13991 (15) | 0.0243 (5) | |
H11A | 0.4206 | 0.6670 | 0.1148 | 0.029* | |
H11B | 0.4621 | 0.7640 | 0.1470 | 0.029* | |
C12 | 0.2846 (3) | 0.76720 (17) | 0.07785 (14) | 0.0231 (5) | |
H12A | 0.3297 | 0.8149 | 0.0462 | 0.028* | |
H12B | 0.2543 | 0.7213 | 0.0381 | 0.028* | |
C13 | 0.1609 (2) | 0.80870 (15) | 0.12310 (14) | 0.0201 (5) | |
C14 | 0.0922 (2) | 0.72936 (16) | 0.17152 (14) | 0.0196 (5) | |
C15 | −0.0535 (2) | 0.74388 (17) | 0.19000 (15) | 0.0228 (5) | |
H15 | −0.0891 | 0.7148 | 0.2402 | 0.027* | |
C16 | −0.1213 (3) | 0.83018 (17) | 0.16126 (16) | 0.0232 (5) | |
C17 | 0.0590 (2) | 0.84230 (16) | 0.05511 (15) | 0.0224 (5) | |
H17 | 0.0360 | 0.7910 | 0.0193 | 0.027* | |
C18 | 0.1966 (3) | 0.88937 (16) | 0.18393 (15) | 0.0233 (5) | |
H18A | 0.1428 | 0.8847 | 0.2347 | 0.035* | |
H18B | 0.1782 | 0.9470 | 0.1562 | 0.035* | |
H18C | 0.2911 | 0.8863 | 0.1986 | 0.035* | |
C19 | 0.4635 (3) | 0.54764 (16) | 0.24976 (15) | 0.0246 (5) | |
H19A | 0.5558 | 0.5324 | 0.2631 | 0.037* | |
H19B | 0.4515 | 0.5476 | 0.1891 | 0.037* | |
H19C | 0.4040 | 0.5028 | 0.2749 | 0.037* | |
C20 | 0.1080 (3) | 0.92041 (16) | −0.00073 (15) | 0.0244 (5) | |
C21 | 0.1952 (3) | 0.91246 (18) | −0.06903 (16) | 0.0278 (6) | |
H21 | 0.2367 | 0.8559 | −0.0873 | 0.033* | |
C22 | 0.0718 (3) | 1.01360 (18) | 0.00268 (17) | 0.0308 (6) | |
H22 | 0.0115 | 1.0408 | 0.0436 | 0.037* | |
C23 | 0.1346 (3) | 1.05895 (17) | −0.06020 (17) | 0.0430 (6) | 0.50 |
H23 | 0.1271 | 1.1238 | −0.0719 | 0.052* | 0.50 |
O8' | 0.1346 (3) | 1.05895 (17) | −0.06020 (17) | 0.0430 (6) | 0.50 |
C28 | 0.4863 (3) | 0.50310 (17) | 0.44778 (17) | 0.0293 (6) | |
H28A | 0.5465 | 0.4902 | 0.4013 | 0.044* | |
H28B | 0.4034 | 0.4693 | 0.4403 | 0.044* | |
H28C | 0.5283 | 0.4850 | 0.5003 | 0.044* | |
C29 | 0.3843 (3) | 0.62676 (18) | 0.53597 (14) | 0.0259 (5) | |
H29A | 0.3106 | 0.5843 | 0.5436 | 0.039* | |
H29B | 0.3501 | 0.6888 | 0.5362 | 0.039* | |
H29C | 0.4484 | 0.6193 | 0.5815 | 0.039* | |
C30 | 0.1717 (3) | 0.56622 (16) | 0.17897 (16) | 0.0261 (5) | |
H30A | 0.2167 | 0.5205 | 0.2129 | 0.039* | |
H30B | 0.2143 | 0.5696 | 0.1241 | 0.039* | |
H30C | 0.0780 | 0.5496 | 0.1722 | 0.039* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0253 (9) | 0.0231 (8) | 0.0276 (9) | −0.0041 (7) | 0.0017 (8) | 0.0018 (7) |
O3 | 0.0336 (11) | 0.0306 (9) | 0.0208 (8) | −0.0050 (9) | −0.0035 (8) | −0.0011 (8) |
O4 | 0.0292 (9) | 0.0268 (8) | 0.0193 (8) | 0.0045 (8) | 0.0042 (8) | −0.0030 (7) |
O5 | 0.0210 (9) | 0.0256 (8) | 0.0277 (9) | −0.0034 (7) | −0.0056 (8) | −0.0029 (7) |
O6 | 0.0188 (9) | 0.0282 (9) | 0.0316 (9) | 0.0038 (7) | 0.0029 (8) | 0.0060 (7) |
O7 | 0.0224 (9) | 0.0320 (10) | 0.0440 (11) | 0.0034 (8) | 0.0093 (9) | 0.0058 (9) |
O8 | 0.0243 (11) | 0.0430 (12) | 0.0288 (11) | −0.0048 (10) | −0.0028 (9) | 0.0132 (10) |
C23' | 0.0243 (11) | 0.0430 (12) | 0.0288 (11) | −0.0048 (10) | −0.0028 (9) | 0.0132 (10) |
C1 | 0.0195 (12) | 0.0271 (12) | 0.0202 (11) | 0.0031 (10) | 0.0009 (10) | −0.0004 (10) |
C2 | 0.0177 (12) | 0.0334 (13) | 0.0262 (13) | 0.0005 (11) | −0.0015 (10) | 0.0029 (10) |
C3 | 0.0200 (12) | 0.0303 (12) | 0.0211 (11) | 0.0023 (11) | −0.0024 (10) | 0.0019 (10) |
C4 | 0.0205 (12) | 0.0237 (11) | 0.0207 (11) | 0.0004 (10) | −0.0011 (10) | 0.0045 (9) |
C5 | 0.0189 (11) | 0.0179 (10) | 0.0184 (10) | 0.0001 (9) | −0.0010 (9) | 0.0009 (9) |
C6 | 0.0218 (12) | 0.0231 (11) | 0.0192 (11) | −0.0017 (10) | 0.0000 (10) | 0.0022 (10) |
C7 | 0.0180 (11) | 0.0206 (11) | 0.0228 (11) | −0.0019 (10) | 0.0008 (10) | 0.0004 (9) |
C8 | 0.0204 (11) | 0.0183 (10) | 0.0182 (11) | 0.0003 (10) | −0.0006 (9) | −0.0006 (9) |
C9 | 0.0208 (12) | 0.0200 (10) | 0.0169 (11) | 0.0021 (10) | 0.0011 (9) | −0.0006 (9) |
C10 | 0.0186 (12) | 0.0224 (11) | 0.0187 (11) | 0.0019 (10) | 0.0001 (9) | 0.0002 (9) |
C11 | 0.0213 (12) | 0.0311 (12) | 0.0204 (12) | 0.0033 (11) | 0.0019 (10) | 0.0038 (10) |
C12 | 0.0227 (12) | 0.0291 (12) | 0.0177 (11) | 0.0035 (10) | 0.0007 (10) | 0.0009 (9) |
C13 | 0.0193 (12) | 0.0219 (11) | 0.0190 (11) | −0.0001 (9) | −0.0001 (10) | 0.0006 (9) |
C14 | 0.0189 (11) | 0.0215 (11) | 0.0183 (11) | −0.0023 (10) | −0.0014 (9) | −0.0022 (9) |
C15 | 0.0205 (12) | 0.0244 (12) | 0.0236 (11) | −0.0014 (10) | 0.0017 (10) | 0.0011 (10) |
C16 | 0.0172 (12) | 0.0237 (12) | 0.0286 (12) | −0.0008 (10) | −0.0003 (11) | 0.0003 (10) |
C17 | 0.0187 (12) | 0.0250 (11) | 0.0235 (11) | 0.0008 (10) | 0.0017 (10) | 0.0004 (10) |
C18 | 0.0253 (13) | 0.0213 (11) | 0.0233 (11) | −0.0028 (10) | −0.0029 (10) | 0.0004 (9) |
C19 | 0.0260 (13) | 0.0242 (12) | 0.0236 (11) | 0.0040 (11) | 0.0003 (11) | −0.0004 (10) |
C20 | 0.0194 (12) | 0.0294 (12) | 0.0245 (12) | 0.0003 (10) | −0.0039 (10) | 0.0037 (10) |
C21 | 0.0267 (14) | 0.0343 (13) | 0.0223 (12) | 0.0030 (11) | 0.0003 (11) | 0.0047 (10) |
C22 | 0.0270 (14) | 0.0297 (12) | 0.0357 (13) | 0.0032 (11) | 0.0007 (11) | 0.0038 (11) |
C23 | 0.0393 (14) | 0.0399 (13) | 0.0497 (14) | −0.0050 (11) | −0.0100 (13) | 0.0178 (12) |
O8' | 0.0393 (14) | 0.0399 (13) | 0.0497 (14) | −0.0050 (11) | −0.0100 (13) | 0.0178 (12) |
C28 | 0.0302 (13) | 0.0280 (13) | 0.0295 (13) | 0.0052 (11) | −0.0020 (11) | 0.0046 (11) |
C29 | 0.0269 (13) | 0.0315 (12) | 0.0193 (11) | −0.0024 (11) | −0.0009 (10) | 0.0035 (10) |
C30 | 0.0305 (14) | 0.0212 (11) | 0.0266 (12) | 0.0002 (11) | −0.0052 (11) | −0.0045 (10) |
O1—C1 | 1.449 (3) | C10—C19 | 1.548 (3) |
O1—H1A | 0.8299 | C11—C12 | 1.541 (3) |
O3—C3 | 1.443 (3) | C11—H11A | 0.9600 |
O3—H3A | 0.8299 | C11—H11B | 0.9600 |
O4—C7 | 1.434 (3) | C12—C13 | 1.534 (3) |
O4—H4 | 0.8299 | C12—H12A | 0.9600 |
O5—C15 | 1.438 (3) | C12—H12B | 0.9600 |
O5—C14 | 1.466 (3) | C13—C14 | 1.536 (3) |
O6—C16 | 1.349 (3) | C13—C17 | 1.545 (3) |
O6—C17 | 1.478 (3) | C13—C18 | 1.551 (3) |
O7—C16 | 1.213 (3) | C14—C15 | 1.480 (3) |
O8—C23 | 1.414 (4) | C15—C16 | 1.488 (3) |
C1—C2 | 1.534 (3) | C15—H15 | 0.9600 |
C1—C10 | 1.554 (3) | C17—C20 | 1.511 (3) |
C1—H1 | 0.9600 | C17—H17 | 0.9600 |
C2—C3 | 1.524 (3) | C18—H18A | 0.9599 |
C2—H2A | 0.9600 | C18—H18B | 0.9599 |
C2—H2B | 0.9600 | C18—H18C | 0.9599 |
C3—C4 | 1.542 (3) | C19—H19A | 0.9599 |
C3—H3 | 0.9600 | C19—H19B | 0.9599 |
C4—C28 | 1.541 (3) | C19—H19C | 0.9599 |
C4—C29 | 1.544 (3) | C20—C21 | 1.380 (4) |
C4—C5 | 1.553 (3) | C20—C22 | 1.398 (4) |
C5—C6 | 1.528 (3) | C21—H21 | 0.9600 |
C5—C10 | 1.565 (3) | C22—C23 | 1.338 (4) |
C5—H5 | 0.9600 | C22—H22 | 0.9600 |
C6—C7 | 1.522 (3) | C23—H23 | 0.9600 |
C6—H6A | 0.9600 | C28—H28A | 0.9599 |
C6—H6B | 0.9600 | C28—H28B | 0.9599 |
C7—C8 | 1.543 (3) | C28—H28C | 0.9599 |
C7—H7 | 0.9600 | C29—H29A | 0.9599 |
C8—C30 | 1.541 (3) | C29—H29B | 0.9599 |
C8—C9 | 1.558 (3) | C29—H29C | 0.9599 |
C8—C14 | 1.558 (3) | C30—H30A | 0.9599 |
C9—C11 | 1.538 (3) | C30—H30B | 0.9599 |
C9—C10 | 1.565 (3) | C30—H30C | 0.9599 |
C9—H9 | 0.9600 | ||
C1—O1—H1A | 109.5 | C13—C12—H12A | 109.0 |
C3—O3—H3A | 109.5 | C11—C12—H12A | 109.0 |
C7—O4—H4 | 109.5 | C13—C12—H12B | 109.0 |
C15—O5—C14 | 61.25 (15) | C11—C12—H12B | 109.0 |
C16—O6—C17 | 119.54 (19) | H12A—C12—H12B | 107.8 |
O1—C1—C2 | 108.9 (2) | C12—C13—C14 | 106.65 (19) |
O1—C1—C10 | 110.14 (19) | C12—C13—C17 | 108.64 (19) |
C2—C1—C10 | 112.32 (19) | C14—C13—C17 | 106.97 (19) |
O1—C1—H1 | 108.5 | C12—C13—C18 | 113.6 (2) |
C2—C1—H1 | 108.5 | C14—C13—C18 | 111.05 (19) |
C10—C1—H1 | 108.5 | C17—C13—C18 | 109.66 (19) |
C3—C2—C1 | 112.9 (2) | O5—C14—C15 | 58.47 (15) |
C3—C2—H2A | 109.0 | O5—C14—C13 | 112.40 (18) |
C1—C2—H2A | 109.0 | C15—C14—C13 | 114.7 (2) |
C3—C2—H2B | 109.0 | O5—C14—C8 | 113.67 (18) |
C1—C2—H2B | 109.0 | C15—C14—C8 | 122.4 (2) |
H2A—C2—H2B | 107.8 | C13—C14—C8 | 119.2 (2) |
O3—C3—C2 | 110.0 (2) | O5—C15—C14 | 60.28 (15) |
O3—C3—C4 | 110.86 (19) | O5—C15—C16 | 113.5 (2) |
C2—C3—C4 | 113.0 (2) | C14—C15—C16 | 119.7 (2) |
O3—C3—H3 | 107.6 | O5—C15—H15 | 117.0 |
C2—C3—H3 | 107.6 | C14—C15—H15 | 117.0 |
C4—C3—H3 | 107.6 | C16—C15—H15 | 117.0 |
C28—C4—C3 | 109.3 (2) | O7—C16—O6 | 119.1 (2) |
C28—C4—C29 | 106.9 (2) | O7—C16—C15 | 122.6 (2) |
C3—C4—C29 | 107.9 (2) | O6—C16—C15 | 118.3 (2) |
C28—C4—C5 | 115.2 (2) | O6—C17—C20 | 105.21 (19) |
C3—C4—C5 | 107.97 (18) | O6—C17—C13 | 110.83 (18) |
C29—C4—C5 | 109.42 (19) | C20—C17—C13 | 115.5 (2) |
C6—C5—C4 | 113.95 (19) | O6—C17—H17 | 108.4 |
C6—C5—C10 | 110.27 (19) | C20—C17—H17 | 108.4 |
C4—C5—C10 | 116.80 (19) | C13—C17—H17 | 108.4 |
C6—C5—H5 | 104.8 | C13—C18—H18A | 109.5 |
C4—C5—H5 | 104.8 | C13—C18—H18B | 109.5 |
C10—C5—H5 | 104.8 | H18A—C18—H18B | 109.5 |
C7—C6—C5 | 112.69 (19) | C13—C18—H18C | 109.5 |
C7—C6—H6A | 109.1 | H18A—C18—H18C | 109.5 |
C5—C6—H6A | 109.1 | H18B—C18—H18C | 109.5 |
C7—C6—H6B | 109.1 | C10—C19—H19A | 109.5 |
C5—C6—H6B | 109.1 | C10—C19—H19B | 109.5 |
H6A—C6—H6B | 107.8 | H19A—C19—H19B | 109.5 |
O4—C7—C6 | 110.56 (19) | C10—C19—H19C | 109.5 |
O4—C7—C8 | 107.90 (18) | H19A—C19—H19C | 109.5 |
C6—C7—C8 | 112.57 (19) | H19B—C19—H19C | 109.5 |
O4—C7—H7 | 108.6 | C21—C20—C22 | 105.6 (2) |
C6—C7—H7 | 108.6 | C21—C20—C17 | 126.0 (2) |
C8—C7—H7 | 108.6 | C22—C20—C17 | 128.3 (2) |
C30—C8—C7 | 108.73 (19) | C20—C21—H21 | 124.7 |
C30—C8—C9 | 113.84 (19) | C23—C22—C20 | 109.2 (3) |
C7—C8—C9 | 108.21 (18) | C23—C22—H22 | 125.4 |
C30—C8—C14 | 107.14 (19) | C20—C22—H22 | 125.4 |
C7—C8—C14 | 110.29 (19) | C22—C23—O8 | 108.3 (2) |
C9—C8—C14 | 108.62 (18) | C22—C23—H23 | 125.9 |
C11—C9—C8 | 112.40 (19) | O8—C23—H23 | 125.9 |
C11—C9—C10 | 113.09 (19) | C4—C28—H28A | 109.5 |
C8—C9—C10 | 115.76 (18) | C4—C28—H28B | 109.5 |
C11—C9—H9 | 104.7 | H28A—C28—H28B | 109.5 |
C8—C9—H9 | 104.7 | C4—C28—H28C | 109.5 |
C10—C9—H9 | 104.7 | H28A—C28—H28C | 109.5 |
C19—C10—C1 | 105.88 (18) | H28B—C28—H28C | 109.5 |
C19—C10—C9 | 113.17 (18) | C4—C29—H29A | 109.5 |
C1—C10—C9 | 109.50 (18) | C4—C29—H29B | 109.5 |
C19—C10—C5 | 114.09 (18) | H29A—C29—H29B | 109.5 |
C1—C10—C5 | 108.49 (18) | C4—C29—H29C | 109.5 |
C9—C10—C5 | 105.62 (18) | H29A—C29—H29C | 109.5 |
C9—C11—C12 | 114.7 (2) | H29B—C29—H29C | 109.5 |
C9—C11—H11A | 108.6 | C8—C30—H30A | 109.5 |
C12—C11—H11A | 108.6 | C8—C30—H30B | 109.5 |
C9—C11—H11B | 108.6 | H30A—C30—H30B | 109.5 |
C12—C11—H11B | 108.6 | C8—C30—H30C | 109.5 |
H11A—C11—H11B | 107.6 | H30A—C30—H30C | 109.5 |
C13—C12—C11 | 112.88 (19) | H30B—C30—H30C | 109.5 |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1A···O7i | 0.83 | 2.24 | 3.015 (3) | 155 |
O4—H4···O3ii | 0.83 | 1.98 | 2.800 (2) | 171 |
Symmetry codes: (i) x+1, y, z; (ii) x−1/2, −y+3/2, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C26H36O7 |
Mr | 460.55 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 153 |
a, b, c (Å) | 9.856 (2), 14.492 (3), 15.714 (3) |
V (Å3) | 2244.5 (8) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.41 × 0.41 × 0.31 |
Data collection | |
Diffractometer | Riguka Mercury CCD diffractometer |
Absorption correction | Multi-scan (Rigaku/MSC, 2006) |
Tmin, Tmax | 0.961, 0.970 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 16840, 2222, 2133 |
Rint | 0.037 |
(sin θ/λ)max (Å−1) | 0.596 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.037, 0.094, 1.07 |
No. of reflections | 2222 |
No. of parameters | 306 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.19, −0.16 |
Computer programs: CrystalClear (Rigaku/MSC, 2006), SHELXTL (Bruker, 2000), PLATON (Spek, 2003).
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1A···O7i | 0.83 | 2.24 | 3.015 (3) | 155.2 |
O4—H4···O3ii | 0.83 | 1.98 | 2.800 (2) | 171.2 |
Symmetry codes: (i) x+1, y, z; (ii) x−1/2, −y+3/2, −z+1. |
1,3,7-trideacetylkhivorin, a D-seco limonoid, has been isolated by trichloromethane extract of the stem bark of African mahogany Khaya senegalensis belonging to the Meliaceae family. Our previous study showed the stem bark extract displayed anti-proliferative effects on HT-29, HCT-15, and HCA-7 cells (Androulakis et al., 2006). In addition, a major D-seco tetranortriterpenoid, 3,7-dideacetylkhivorin, isolated from the same extract, exhibited growth inhibitory activities against MCF-7, SiHa, and Caco-2 cells with IC50 values in the range of 35–69 µg/ml (Zhang, Wang et al., 2007). In our furthur investigations of the anti-tumor constituents of this African mahogany, another minor tetranortriterpenoid, the title compound, named 14,15β:21,23-diepoxy-1α,3α,7α-trihydroxy-4,4,8-trimethyl-D-homo-24-nor-17-oxochola-20,22-diene-16-one, was purified from the plant extract for the first time. It was reported as a synthetic derivative by basic hydrolysis of khivorin (Bevan et al., 1963) and isolated as a natural product from Khaya ivorensis recently (Abdelgaleil et al., 2005). In our preliminary in vitro anti-cancer bioassay, the title compound showed similar bioactivies to those of two other D-seco limonoids, 3,7-dideacetyl khivorin and gedunin (Uddin et al., 2007). Herein, the X-ray crystal analysis of the title compound was undertaken to establish its structure and relative stereochemistry, which will benefit further work on structure–activity relationships of anti-tumor bioactivities of D-seco limonoids.
Fig. 1 is a thermal ellipsoid plot with atomic labeling of the title compound. The structure contains four six-membered rings A–D, one three-membered ring E, and one furan ring F linked to ring D through a C—C bond in an equatorial position, known as a D-seco limonoid. The ring junctions A/B, B/C and C/D are all trans, while D/E is cis. The six-membered rings A–D adopt chair, chair, twist boat and half-chair conformations, while rings E and F are essentially planar. The five-membered furan ring is disordered by a 180° rotation about the C17—C20 bond.
All the bond lengths and angles are close to their expected values and the data are comparable with the corresponding values in those of gedunin (Toscano et al., 1996) and 3,7-dideacetylkhivorin (Zhang, VanDerveer et al., 2007).
The title compound exhibits strong classical intermolecular O1—H1A···O7, O4—H4···O3 hydrogen bond interactions (Table 1), which link the molecules together to form a stablized network.