The asymmetric unit of ludongnin consists of two molecules of C20H24O6. The hydroxyl group of each molecule participates in a hydrogen bond with the carbonyl oxygen of the δ-lactone moiety of a translationally related molecule, thus giving rise to the two symmetry-independent sets of infinite chains in the crystal, one of which is stretched along the c and another along the a axis of the crystal.
Supporting information
CCDC reference: 170889
Key indicators
- Single-crystal X-ray study
- T = 291 K
- Mean (C-C) = 0.005 Å
- R factor = 0.038
- wR factor = 0.081
- Data-to-parameter ratio = 7.3
checkCIF results
No syntax errors found
ADDSYM reports no extra symmetry
Alert Level C:
STRVAL_01
From the CIF: _refine_ls_abs_structure_Flack -0.400
From the CIF: _refine_ls_abs_structure_Flack_su 1.100
Alert C Flack parameter is too small
General Notes
REFLT_03
From the CIF: _diffrn_reflns_theta_max 26.00
From the CIF: _reflns_number_total 3474
Count of symmetry unique reflns 3478
Completeness (_total/calc) 99.88%
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
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.
0 Alert Level A = Potentially serious problem
0 Alert Level B = Potential problem
1 Alert Level C = Please check
2 kg of dried powder of the whole herb of Rabdosia var lophanthoides were soaked
three times with 95% EtOH at room temperature. The ethanolic extracts were
evaporated under reduced pressure, the residue was successively fractioned
with petroleum ether, EtOAc and n-BuOH. The residue of EtOAc fraction was
subjected to column chromatography over silica gel. The column was eluted with
a petroleum ether–EtOAc mixture; the acetone–chloroform mixture was used for
recrystallization of the title compound. Its purity was checked by 1H NMR
spectroscopy. α12D - 138° (c = 1, pyridine); UVλmax (95%EtOH): 230 nm
(ε 7130). Crystals suitable for X-ray structure analysis were obtained by
slow evaporation from an aqueous solution containing chloroform and methanol
in a 1:1 ratio at room temperature.
H atoms were placed in geometrically calculated positions and included in the
final refinement in the riding-model approximation with the displacement
parameters Uiso set equal to 1.2Ueq of the corresponding
carrier atom. As one would expect, both independent molecules have the same
configuration. Lack of the anomalous scatterers and, hence, high s.u. of the
Flack parameter, -0.4 (11), do not permit to make unambiguous assignment of the
absolute configuration of the title compound.
Data collection: XSCANS (Siemens, 1994); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP in SHELXTL/PC (Siemens, 1991); software used to prepare material for publication: SHELXTL97.
octahydro-5'-hydroxy-7a-methyl-8'- methylene-spiro [isobenzofuran-4 (1H), 4'
(3'H) - [1
H-7, 9a] methanocyclohepta[
c]pyran] -1', 3, 9' (3aH,
4'aH) -trione
top
Crystal data top
C20H24O6 | Dx = 1.368 Mg m−3 |
Mr = 360.39 | Melting point = 538–540 K |
Monoclinic, P21 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.2397 (13) Å | Cell parameters from 18 reflections |
b = 36.724 (8) Å | θ = 3.1–14.2° |
c = 7.304 (2) Å | µ = 0.10 mm−1 |
β = 115.69 (2)° | T = 291 K |
V = 1749.9 (7) Å3 | Prism, colorless |
Z = 4 | 0.52 × 0.44 × 0.42 mm |
F(000) = 768 | |
Data collection top
Siemens P4 diffractometer | Rint = 0.017 |
Radiation source: normal-focus sealed tube | θmax = 26.0°, θmin = 2.2° |
Graphite monochromator | h = 0→8 |
ω scans | k = 0→45 |
3894 measured reflections | l = −9→8 |
3474 independent reflections | 3 standard reflections every 97 reflections |
2512 reflections with I > 2σ(I) | intensity decay: 3.6% |
Refinement top
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.038 | w = 1/[σ2(Fo2) + (0.0428P)2] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.081 | (Δ/σ)max = 0.001 |
S = 0.91 | Δρmax = 0.17 e Å−3 |
3474 reflections | Δρmin = −0.14 e Å−3 |
474 parameters | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
1 restraint | Extinction coefficient: 0.0135 (12) |
Primary atom site location: structure-invariant direct methods | Absolute structure: Flack (1983) |
Secondary atom site location: difference Fourier map | Absolute structure parameter: −0.4 (11) |
Crystal data top
C20H24O6 | V = 1749.9 (7) Å3 |
Mr = 360.39 | Z = 4 |
Monoclinic, P21 | Mo Kα radiation |
a = 7.2397 (13) Å | µ = 0.10 mm−1 |
b = 36.724 (8) Å | T = 291 K |
c = 7.304 (2) Å | 0.52 × 0.44 × 0.42 mm |
β = 115.69 (2)° | |
Data collection top
Siemens P4 diffractometer | Rint = 0.017 |
3894 measured reflections | 3 standard reflections every 97 reflections |
3474 independent reflections | intensity decay: 3.6% |
2512 reflections with I > 2σ(I) | |
Refinement top
R[F2 > 2σ(F2)] = 0.038 | H-atom parameters constrained |
wR(F2) = 0.081 | Δρmax = 0.17 e Å−3 |
S = 0.91 | Δρmin = −0.14 e Å−3 |
3474 reflections | Absolute structure: Flack (1983) |
474 parameters | Absolute structure parameter: −0.4 (11) |
1 restraint | |
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 | x | y | z | Uiso*/Ueq | |
O1 | 0.3281 (4) | 0.21845 (8) | 0.3993 (4) | 0.0600 (7) | |
H1A | 0.3138 | 0.2270 | 0.2902 | 0.090* | |
O2 | 0.6199 (4) | 0.25371 (7) | 1.1879 (3) | 0.0514 (7) | |
O3 | 0.1614 (4) | 0.24262 (8) | 0.9923 (4) | 0.0585 (7) | |
O4 | 0.0682 (3) | 0.26942 (7) | 0.7008 (4) | 0.0479 (6) | |
O5 | 0.3429 (5) | 0.38238 (7) | 0.8393 (5) | 0.0696 (8) | |
O6 | 0.0656 (4) | 0.35278 (8) | 0.6352 (5) | 0.0805 (10) | |
C1 | 0.3685 (5) | 0.30797 (10) | 0.4311 (5) | 0.0439 (9) | |
H1B | 0.3496 | 0.2888 | 0.3333 | 0.053* | |
H1C | 0.2632 | 0.3262 | 0.3653 | 0.053* | |
C2 | 0.5779 (6) | 0.32529 (10) | 0.4931 (5) | 0.0502 (9) | |
H2A | 0.6835 | 0.3070 | 0.5546 | 0.060* | |
H2B | 0.5878 | 0.3346 | 0.3734 | 0.060* | |
C3 | 0.6129 (6) | 0.35612 (10) | 0.6426 (6) | 0.0508 (10) | |
H3A | 0.5105 | 0.3749 | 0.5790 | 0.061* | |
H3B | 0.7467 | 0.3668 | 0.6781 | 0.061* | |
C4 | 0.6011 (5) | 0.34284 (9) | 0.8365 (5) | 0.0429 (9) | |
C5 | 0.4000 (5) | 0.32149 (9) | 0.7821 (5) | 0.0375 (8) | |
H5A | 0.4122 | 0.3093 | 0.9061 | 0.045* | |
C6 | 0.2460 (7) | 0.35231 (10) | 0.7390 (7) | 0.0535 (10) | |
C7 | 0.2028 (5) | 0.24993 (10) | 0.8529 (5) | 0.0408 (8) | |
C8 | 0.3906 (5) | 0.23568 (9) | 0.8393 (4) | 0.0339 (7) | |
C9 | 0.4739 (5) | 0.25749 (9) | 0.7041 (4) | 0.0330 (7) | |
H9A | 0.6088 | 0.2666 | 0.7991 | 0.040* | |
C10 | 0.3422 (5) | 0.29189 (9) | 0.6134 (5) | 0.0336 (7) | |
C11 | 0.5155 (6) | 0.23190 (9) | 0.5589 (5) | 0.0421 (8) | |
H11A | 0.5906 | 0.2455 | 0.4972 | 0.051* | |
C12 | 0.6456 (6) | 0.19966 (10) | 0.6745 (5) | 0.0516 (10) | |
H12A | 0.7875 | 0.2074 | 0.7439 | 0.062* | |
H12B | 0.6374 | 0.1808 | 0.5781 | 0.062* | |
C13 | 0.5798 (5) | 0.18343 (9) | 0.8314 (5) | 0.0473 (9) | |
H13A | 0.5937 | 0.1569 | 0.8375 | 0.057* | |
C14 | 0.3601 (5) | 0.19488 (9) | 0.7802 (5) | 0.0428 (8) | |
H14A | 0.3053 | 0.1815 | 0.8602 | 0.051* | |
H14B | 0.2707 | 0.1916 | 0.6369 | 0.051* | |
C15 | 0.5757 (5) | 0.23262 (9) | 1.0485 (5) | 0.0373 (8) | |
C16 | 0.6929 (5) | 0.20013 (10) | 1.0379 (5) | 0.0457 (9) | |
C17 | 0.8627 (6) | 0.18976 (12) | 1.1911 (7) | 0.0714 (13) | |
H17A | 0.9138 | 0.2029 | 1.3119 | 0.086* | |
H17B | 0.9321 | 0.1693 | 1.1790 | 0.086* | |
C18 | 0.8024 (6) | 0.32473 (11) | 0.9816 (6) | 0.0596 (11) | |
H18A | 0.9047 | 0.3431 | 1.0455 | 0.089* | |
H18B | 0.8477 | 0.3084 | 0.9066 | 0.089* | |
H18C | 0.7809 | 0.3113 | 1.0836 | 0.089* | |
C19 | 0.5605 (7) | 0.37542 (11) | 0.9432 (7) | 0.0649 (12) | |
H19A | 0.6004 | 0.3699 | 1.0853 | 0.078* | |
H19B | 0.6373 | 0.3965 | 0.9347 | 0.078* | |
C20 | 0.1186 (5) | 0.27993 (10) | 0.5349 (5) | 0.0440 (9) | |
H20A | 0.0298 | 0.2997 | 0.4590 | 0.053* | |
H20B | 0.0939 | 0.2595 | 0.4433 | 0.053* | |
O1' | −0.3955 (3) | 0.58886 (7) | 0.1686 (4) | 0.0527 (7) | |
H1'A | −0.5010 | 0.5770 | 0.1377 | 0.079* | |
O2' | 0.3896 (3) | 0.54835 (7) | 0.4384 (3) | 0.0478 (6) | |
O3' | 0.1919 (4) | 0.56283 (8) | −0.0129 (4) | 0.0552 (7) | |
O4' | −0.1052 (3) | 0.53694 (7) | −0.1068 (3) | 0.0463 (6) | |
O5' | 0.0239 (5) | 0.42278 (7) | 0.1509 (4) | 0.0660 (8) | |
O6' | −0.1798 (5) | 0.45366 (8) | −0.1190 (4) | 0.0742 (9) | |
C1' | −0.3756 (5) | 0.49813 (10) | 0.1919 (5) | 0.0405 (8) | |
H1'B | −0.4719 | 0.5176 | 0.1758 | 0.049* | |
H1'C | −0.4449 | 0.4803 | 0.0861 | 0.049* | |
C2' | −0.3138 (5) | 0.48014 (9) | 0.3990 (5) | 0.0449 (9) | |
H2'A | −0.2480 | 0.4979 | 0.5059 | 0.054* | |
H2'B | −0.4350 | 0.4712 | 0.4092 | 0.054* | |
C3' | −0.1683 (5) | 0.44896 (9) | 0.4252 (5) | 0.0449 (9) | |
H3'A | −0.2368 | 0.4310 | 0.3203 | 0.054* | |
H3'B | −0.1330 | 0.4375 | 0.5558 | 0.054* | |
C4' | 0.0288 (5) | 0.46125 (9) | 0.4137 (5) | 0.0427 (8) | |
C5' | −0.0268 (5) | 0.48378 (9) | 0.2165 (5) | 0.0366 (8) | |
H5'A | 0.0991 | 0.4958 | 0.2294 | 0.044* | |
C6' | −0.0730 (6) | 0.45338 (10) | 0.0600 (6) | 0.0513 (10) | |
C7' | 0.0517 (5) | 0.55599 (9) | 0.0281 (5) | 0.0400 (8) | |
C8' | 0.0432 (4) | 0.56942 (9) | 0.2179 (4) | 0.0327 (7) | |
C9' | −0.0943 (4) | 0.54763 (8) | 0.3002 (5) | 0.0318 (7) | |
H9'A | 0.0014 | 0.5378 | 0.4321 | 0.038* | |
C10' | −0.1931 (5) | 0.51372 (8) | 0.1640 (5) | 0.0319 (7) | |
C11' | −0.2352 (5) | 0.57350 (9) | 0.3464 (5) | 0.0404 (8) | |
H11B | −0.2980 | 0.5598 | 0.4200 | 0.048* | |
C12' | −0.1095 (5) | 0.60452 (9) | 0.4824 (6) | 0.0463 (9) | |
H12C | −0.0376 | 0.5956 | 0.6205 | 0.056* | |
H12D | −0.2021 | 0.6236 | 0.4825 | 0.056* | |
C13' | 0.0478 (5) | 0.62090 (9) | 0.4159 (5) | 0.0422 (8) | |
H13B | 0.0567 | 0.6474 | 0.4337 | 0.051* | |
C14' | −0.0106 (5) | 0.61039 (9) | 0.1943 (5) | 0.0406 (8) | |
H14C | 0.0700 | 0.6237 | 0.1396 | 0.049* | |
H14D | −0.1552 | 0.6144 | 0.1088 | 0.049* | |
C15' | 0.2536 (5) | 0.57060 (9) | 0.3983 (5) | 0.0360 (7) | |
C16' | 0.2567 (5) | 0.60343 (10) | 0.5193 (5) | 0.0439 (9) | |
C17' | 0.4243 (6) | 0.61465 (11) | 0.6755 (6) | 0.0631 (11) | |
H17C | 0.5464 | 0.6019 | 0.7136 | 0.076* | |
H17D | 0.4202 | 0.6353 | 0.7474 | 0.076* | |
C18' | 0.1781 (6) | 0.47852 (11) | 0.6149 (5) | 0.0597 (11) | |
H18D | 0.2360 | 0.4599 | 0.7160 | 0.090* | |
H18E | 0.1060 | 0.4958 | 0.6587 | 0.090* | |
H18F | 0.2857 | 0.4907 | 0.5958 | 0.090* | |
C19' | 0.1308 (6) | 0.42868 (11) | 0.3676 (6) | 0.0606 (11) | |
H19C | 0.2747 | 0.4336 | 0.4071 | 0.073* | |
H19D | 0.1200 | 0.4074 | 0.4408 | 0.073* | |
C20' | −0.2718 (5) | 0.52686 (10) | −0.0559 (5) | 0.0436 (9) | |
H20C | −0.3524 | 0.5077 | −0.1468 | 0.052* | |
H20D | −0.3607 | 0.5477 | −0.0760 | 0.052* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
O1 | 0.0748 (19) | 0.0685 (18) | 0.0303 (13) | −0.0124 (15) | 0.0169 (14) | −0.0058 (13) |
O2 | 0.0602 (16) | 0.0631 (17) | 0.0293 (13) | −0.0091 (14) | 0.0180 (12) | −0.0050 (13) |
O3 | 0.0533 (16) | 0.083 (2) | 0.0500 (15) | −0.0010 (14) | 0.0324 (13) | 0.0143 (14) |
O4 | 0.0352 (13) | 0.0572 (16) | 0.0518 (14) | 0.0037 (12) | 0.0194 (12) | 0.0180 (12) |
O5 | 0.077 (2) | 0.0399 (16) | 0.107 (2) | 0.0044 (15) | 0.054 (2) | −0.0053 (16) |
O6 | 0.0490 (18) | 0.0619 (19) | 0.136 (3) | 0.0156 (16) | 0.0452 (19) | 0.017 (2) |
C1 | 0.052 (2) | 0.047 (2) | 0.0352 (19) | 0.0036 (18) | 0.0210 (17) | 0.0121 (16) |
C2 | 0.057 (2) | 0.054 (2) | 0.051 (2) | 0.0043 (19) | 0.033 (2) | 0.0153 (19) |
C3 | 0.045 (2) | 0.046 (2) | 0.067 (3) | 0.0016 (18) | 0.030 (2) | 0.014 (2) |
C4 | 0.044 (2) | 0.0344 (19) | 0.048 (2) | −0.0049 (16) | 0.0175 (18) | 0.0012 (16) |
C5 | 0.0406 (19) | 0.0372 (19) | 0.0410 (19) | 0.0003 (16) | 0.0237 (16) | 0.0070 (15) |
C6 | 0.058 (3) | 0.037 (2) | 0.085 (3) | 0.005 (2) | 0.049 (2) | 0.010 (2) |
C7 | 0.0369 (19) | 0.044 (2) | 0.0406 (19) | −0.0105 (17) | 0.0163 (17) | 0.0026 (17) |
C8 | 0.0353 (18) | 0.0375 (17) | 0.0287 (16) | −0.0019 (15) | 0.0136 (15) | 0.0080 (14) |
C9 | 0.0325 (17) | 0.0403 (19) | 0.0261 (16) | −0.0039 (15) | 0.0125 (14) | 0.0015 (14) |
C10 | 0.0287 (17) | 0.0387 (18) | 0.0300 (18) | 0.0019 (15) | 0.0096 (15) | 0.0053 (14) |
C11 | 0.052 (2) | 0.042 (2) | 0.0359 (18) | −0.0039 (18) | 0.0219 (17) | −0.0026 (16) |
C12 | 0.059 (2) | 0.044 (2) | 0.054 (2) | 0.0054 (19) | 0.027 (2) | −0.0071 (18) |
C13 | 0.051 (2) | 0.0302 (19) | 0.056 (2) | 0.0018 (17) | 0.0183 (19) | 0.0008 (16) |
C14 | 0.045 (2) | 0.0371 (19) | 0.0415 (19) | −0.0080 (17) | 0.0139 (16) | 0.0028 (16) |
C15 | 0.038 (2) | 0.0417 (19) | 0.0315 (18) | −0.0102 (16) | 0.0147 (15) | 0.0059 (16) |
C16 | 0.043 (2) | 0.042 (2) | 0.046 (2) | −0.0008 (17) | 0.0135 (18) | 0.0128 (17) |
C17 | 0.058 (3) | 0.060 (3) | 0.071 (3) | 0.006 (2) | 0.005 (2) | 0.017 (2) |
C18 | 0.050 (2) | 0.052 (2) | 0.059 (2) | −0.011 (2) | 0.007 (2) | −0.001 (2) |
C19 | 0.081 (3) | 0.045 (2) | 0.071 (3) | −0.008 (2) | 0.035 (3) | −0.008 (2) |
C20 | 0.040 (2) | 0.049 (2) | 0.039 (2) | 0.0025 (17) | 0.0137 (17) | 0.0127 (17) |
O1' | 0.0290 (13) | 0.0479 (15) | 0.0725 (18) | 0.0016 (11) | 0.0138 (13) | 0.0106 (13) |
O2' | 0.0318 (13) | 0.0583 (16) | 0.0522 (15) | 0.0030 (13) | 0.0171 (12) | 0.0036 (13) |
O3' | 0.0458 (15) | 0.082 (2) | 0.0449 (14) | −0.0119 (14) | 0.0262 (12) | 0.0014 (14) |
O4' | 0.0484 (14) | 0.0579 (16) | 0.0319 (12) | −0.0129 (13) | 0.0168 (11) | 0.0010 (11) |
O5' | 0.099 (2) | 0.0388 (15) | 0.076 (2) | 0.0060 (15) | 0.0525 (18) | −0.0044 (15) |
O6' | 0.123 (3) | 0.0601 (18) | 0.0429 (16) | −0.0122 (19) | 0.0390 (18) | −0.0123 (14) |
C1' | 0.0336 (18) | 0.0372 (18) | 0.046 (2) | −0.0055 (16) | 0.0130 (16) | −0.0008 (16) |
C2' | 0.049 (2) | 0.042 (2) | 0.054 (2) | −0.0097 (18) | 0.0333 (19) | −0.0002 (17) |
C3' | 0.063 (2) | 0.0356 (19) | 0.040 (2) | −0.0060 (18) | 0.0262 (18) | 0.0029 (15) |
C4' | 0.047 (2) | 0.0353 (19) | 0.044 (2) | −0.0023 (17) | 0.0178 (18) | 0.0042 (16) |
C5' | 0.0383 (19) | 0.0343 (18) | 0.0414 (19) | −0.0041 (15) | 0.0214 (16) | −0.0005 (15) |
C6' | 0.071 (3) | 0.036 (2) | 0.061 (3) | −0.008 (2) | 0.042 (2) | −0.0043 (19) |
C7' | 0.0353 (19) | 0.045 (2) | 0.0391 (19) | −0.0038 (16) | 0.0158 (17) | 0.0084 (16) |
C8' | 0.0291 (17) | 0.0338 (17) | 0.0347 (17) | −0.0040 (15) | 0.0136 (14) | 0.0015 (15) |
C9' | 0.0275 (16) | 0.0315 (17) | 0.0368 (17) | −0.0020 (14) | 0.0144 (14) | 0.0043 (14) |
C10' | 0.0301 (17) | 0.0323 (17) | 0.0322 (17) | −0.0023 (14) | 0.0125 (14) | 0.0026 (14) |
C11' | 0.0353 (18) | 0.0374 (19) | 0.051 (2) | 0.0007 (16) | 0.0213 (17) | 0.0038 (17) |
C12' | 0.047 (2) | 0.0371 (19) | 0.058 (2) | −0.0004 (17) | 0.0250 (19) | −0.0022 (18) |
C13' | 0.041 (2) | 0.0291 (17) | 0.054 (2) | −0.0029 (15) | 0.0178 (18) | −0.0007 (16) |
C14' | 0.0357 (18) | 0.0378 (19) | 0.046 (2) | −0.0049 (16) | 0.0158 (16) | 0.0096 (16) |
C15' | 0.0270 (17) | 0.0389 (18) | 0.0454 (19) | 0.0005 (16) | 0.0189 (15) | 0.0068 (16) |
C16' | 0.040 (2) | 0.042 (2) | 0.042 (2) | −0.0050 (17) | 0.0112 (17) | −0.0020 (16) |
C17' | 0.062 (3) | 0.049 (2) | 0.057 (2) | 0.004 (2) | 0.005 (2) | −0.006 (2) |
C18' | 0.064 (3) | 0.050 (2) | 0.044 (2) | 0.002 (2) | 0.004 (2) | 0.0097 (19) |
C19' | 0.061 (3) | 0.045 (2) | 0.074 (3) | 0.013 (2) | 0.028 (2) | 0.008 (2) |
C20' | 0.0348 (18) | 0.053 (2) | 0.0358 (18) | −0.0054 (17) | 0.0087 (15) | 0.0053 (17) |
Geometric parameters (Å, º) top
O1—C11 | 1.439 (4) | O1'—C11' | 1.430 (4) |
O1—H1A | 0.8200 | O1'—H1'A | 0.8200 |
O2—C15 | 1.207 (4) | O2'—C15' | 1.213 (4) |
O3—C7 | 1.210 (4) | O3'—C7' | 1.204 (4) |
O4—C7 | 1.326 (4) | O4'—C7' | 1.334 (4) |
O4—C20 | 1.461 (4) | O4'—C20' | 1.456 (4) |
O5—C6 | 1.343 (5) | O5'—C6' | 1.339 (5) |
O5—C19 | 1.444 (5) | O5'—C19' | 1.445 (4) |
O6—C6 | 1.193 (5) | O6'—C6' | 1.196 (5) |
C1—C2 | 1.521 (5) | C1'—C2' | 1.529 (5) |
C1—C10 | 1.542 (4) | C1'—C10' | 1.532 (4) |
C1—H1B | 0.9700 | C1'—H1'B | 0.9700 |
C1—H1C | 0.9700 | C1'—H1'C | 0.9700 |
C2—C3 | 1.516 (5) | C2'—C3' | 1.511 (5) |
C2—H2A | 0.9700 | C2'—H2'A | 0.9700 |
C2—H2B | 0.9700 | C2'—H2'B | 0.9700 |
C3—C4 | 1.535 (5) | C3'—C4' | 1.533 (5) |
C3—H3A | 0.9700 | C3'—H3'A | 0.9700 |
C3—H3B | 0.9700 | C3'—H3'B | 0.9700 |
C4—C19 | 1.524 (5) | C4'—C19' | 1.519 (5) |
C4—C18 | 1.533 (5) | C4'—C18' | 1.534 (5) |
C4—C5 | 1.546 (5) | C4'—C5' | 1.556 (5) |
C5—C6 | 1.523 (5) | C5'—C6' | 1.527 (5) |
C5—C10 | 1.558 (5) | C5'—C10' | 1.551 (4) |
C5—H5A | 0.9800 | C5'—H5'A | 0.9800 |
C7—C8 | 1.499 (5) | C7'—C8' | 1.497 (5) |
C8—C15 | 1.539 (4) | C8'—C15' | 1.523 (4) |
C8—C14 | 1.549 (5) | C8'—C14' | 1.545 (5) |
C8—C9 | 1.581 (4) | C8'—C9' | 1.585 (4) |
C9—C11 | 1.541 (4) | C9'—C11' | 1.535 (4) |
C9—C10 | 1.548 (4) | C9'—C10' | 1.560 (4) |
C9—H9A | 0.9800 | C9'—H9'A | 0.9800 |
C10—C20 | 1.528 (4) | C10'—C20' | 1.531 (4) |
C11—C12 | 1.521 (5) | C11'—C12' | 1.526 (5) |
C11—H11A | 0.9800 | C11'—H11B | 0.9800 |
C12—C13 | 1.539 (5) | C12'—C13' | 1.541 (5) |
C12—H12A | 0.9700 | C12'—H12C | 0.9700 |
C12—H12B | 0.9700 | C12'—H12D | 0.9700 |
C13—C16 | 1.500 (5) | C13'—C16' | 1.510 (5) |
C13—C14 | 1.527 (5) | C13'—C14' | 1.534 (5) |
C13—H13A | 0.9800 | C13'—H13B | 0.9800 |
C14—H14A | 0.9700 | C14'—H14C | 0.9700 |
C14—H14B | 0.9700 | C14'—H14D | 0.9700 |
C15—C16 | 1.486 (5) | C15'—C16' | 1.489 (5) |
C16—C17 | 1.310 (5) | C16'—C17' | 1.320 (5) |
C17—H17A | 0.9300 | C17'—H17C | 0.9300 |
C17—H17B | 0.9300 | C17'—H17D | 0.9300 |
C18—H18A | 0.9600 | C18'—H18D | 0.9600 |
C18—H18B | 0.9600 | C18'—H18E | 0.9600 |
C18—H18C | 0.9600 | C18'—H18F | 0.9600 |
C19—H19A | 0.9700 | C19'—H19C | 0.9700 |
C19—H19B | 0.9700 | C19'—H19D | 0.9700 |
C20—H20A | 0.9700 | C20'—H20C | 0.9700 |
C20—H20B | 0.9700 | C20'—H20D | 0.9700 |
| | | |
C11—O1—H1A | 109.5 | C11'—O1'—H1'A | 109.5 |
C7—O4—C20 | 118.7 (3) | C7'—O4'—C20' | 118.6 (3) |
C6—O5—C19 | 109.5 (3) | C6'—O5'—C19' | 109.5 (3) |
C2—C1—C10 | 112.5 (3) | C2'—C1'—C10' | 113.2 (3) |
C2—C1—H1B | 109.1 | C2'—C1'—H1'B | 108.9 |
C10—C1—H1B | 109.1 | C10'—C1'—H1'B | 108.9 |
C2—C1—H1C | 109.1 | C2'—C1'—H1'C | 108.9 |
C10—C1—H1C | 109.1 | C10'—C1'—H1'C | 108.9 |
H1B—C1—H1C | 107.8 | H1'B—C1'—H1'C | 107.8 |
C3—C2—C1 | 111.2 (3) | C3'—C2'—C1' | 110.0 (3) |
C3—C2—H2A | 109.4 | C3'—C2'—H2'A | 109.7 |
C1—C2—H2A | 109.4 | C1'—C2'—H2'A | 109.7 |
C3—C2—H2B | 109.4 | C3'—C2'—H2'B | 109.7 |
C1—C2—H2B | 109.4 | C1'—C2'—H2'B | 109.7 |
H2A—C2—H2B | 108.0 | H2'A—C2'—H2'B | 108.2 |
C2—C3—C4 | 111.6 (3) | C2'—C3'—C4' | 112.6 (3) |
C2—C3—H3A | 109.3 | C2'—C3'—H3'A | 109.1 |
C4—C3—H3A | 109.3 | C4'—C3'—H3'A | 109.1 |
C2—C3—H3B | 109.3 | C2'—C3'—H3'B | 109.1 |
C4—C3—H3B | 109.3 | C4'—C3'—H3'B | 109.1 |
H3A—C3—H3B | 108.0 | H3'A—C3'—H3'B | 107.8 |
C19—C4—C18 | 108.9 (3) | C19'—C4'—C3' | 109.5 (3) |
C19—C4—C3 | 108.8 (3) | C19'—C4'—C18' | 109.2 (3) |
C18—C4—C3 | 111.0 (3) | C3'—C4'—C18' | 110.8 (3) |
C19—C4—C5 | 99.2 (3) | C19'—C4'—C5' | 99.7 (3) |
C18—C4—C5 | 117.7 (3) | C3'—C4'—C5' | 109.5 (3) |
C3—C4—C5 | 110.3 (3) | C18'—C4'—C5' | 117.3 (3) |
C6—C5—C4 | 101.5 (3) | C6'—C5'—C10' | 116.0 (3) |
C6—C5—C10 | 115.7 (3) | C6'—C5'—C4' | 100.9 (3) |
C4—C5—C10 | 117.2 (3) | C10'—C5'—C4' | 117.9 (3) |
C6—C5—H5A | 107.3 | C6'—C5'—H5'A | 107.1 |
C4—C5—H5A | 107.3 | C10'—C5'—H5'A | 107.1 |
C10—C5—H5A | 107.3 | C4'—C5'—H5'A | 107.1 |
O6—C6—O5 | 120.3 (4) | O6'—C6'—O5' | 120.1 (4) |
O6—C6—C5 | 130.1 (4) | O6'—C6'—C5' | 129.8 (4) |
O5—C6—C5 | 109.6 (3) | O5'—C6'—C5' | 110.2 (3) |
O3—C7—O4 | 117.7 (3) | O3'—C7'—O4' | 117.7 (3) |
O3—C7—C8 | 122.7 (3) | O3'—C7'—C8' | 122.6 (3) |
O4—C7—C8 | 119.5 (3) | O4'—C7'—C8' | 119.6 (3) |
C7—C8—C15 | 112.6 (3) | C7'—C8'—C15' | 112.5 (3) |
C7—C8—C14 | 109.4 (3) | C7'—C8'—C14' | 109.1 (3) |
C15—C8—C14 | 99.4 (3) | C15'—C8'—C14' | 100.3 (3) |
C7—C8—C9 | 117.8 (3) | C7'—C8'—C9' | 118.0 (3) |
C15—C8—C9 | 104.7 (2) | C15'—C8'—C9' | 104.1 (2) |
C14—C8—C9 | 111.3 (3) | C14'—C8'—C9' | 111.4 (3) |
C11—C9—C10 | 118.1 (2) | C11'—C9'—C10' | 118.0 (2) |
C11—C9—C8 | 111.2 (3) | C11'—C9'—C8' | 110.9 (2) |
C10—C9—C8 | 110.5 (2) | C10'—C9'—C8' | 110.5 (2) |
C11—C9—H9A | 105.3 | C11'—C9'—H9'A | 105.4 |
C10—C9—H9A | 105.3 | C10'—C9'—H9'A | 105.4 |
C8—C9—H9A | 105.3 | C8'—C9'—H9'A | 105.4 |
C20—C10—C1 | 107.1 (2) | C20'—C10'—C1' | 107.9 (2) |
C20—C10—C9 | 106.4 (3) | C20'—C10'—C5' | 112.3 (3) |
C1—C10—C9 | 113.5 (3) | C1'—C10'—C5' | 108.9 (3) |
C20—C10—C5 | 112.0 (3) | C20'—C10'—C9' | 106.1 (2) |
C1—C10—C5 | 108.9 (3) | C1'—C10'—C9' | 113.4 (3) |
C9—C10—C5 | 109.1 (2) | C5'—C10'—C9' | 108.4 (2) |
O1—C11—C12 | 108.8 (3) | O1'—C11'—C12' | 108.5 (3) |
O1—C11—C9 | 111.7 (3) | O1'—C11'—C9' | 113.5 (3) |
C12—C11—C9 | 110.6 (3) | C12'—C11'—C9' | 109.9 (3) |
O1—C11—H11A | 108.6 | O1'—C11'—H11B | 108.3 |
C12—C11—H11A | 108.6 | C12'—C11'—H11B | 108.3 |
C9—C11—H11A | 108.6 | C9'—C11'—H11B | 108.3 |
C11—C12—C13 | 113.5 (3) | C11'—C12'—C13' | 113.6 (3) |
C11—C12—H12A | 108.9 | C11'—C12'—H12C | 108.9 |
C13—C12—H12A | 108.9 | C13'—C12'—H12C | 108.9 |
C11—C12—H12B | 108.9 | C11'—C12'—H12D | 108.9 |
C13—C12—H12B | 108.9 | C13'—C12'—H12D | 108.9 |
H12A—C12—H12B | 107.7 | H12C—C12'—H12D | 107.7 |
C16—C13—C14 | 101.0 (3) | C16'—C13'—C14' | 100.3 (3) |
C16—C13—C12 | 112.3 (3) | C16'—C13'—C12' | 113.2 (3) |
C14—C13—C12 | 109.7 (3) | C14'—C13'—C12' | 109.3 (3) |
C16—C13—H13A | 111.1 | C16'—C13'—H13B | 111.2 |
C14—C13—H13A | 111.1 | C14'—C13'—H13B | 111.2 |
C12—C13—H13A | 111.1 | C12'—C13'—H13B | 111.2 |
C13—C14—C8 | 101.0 (3) | C13'—C14'—C8' | 100.7 (2) |
C13—C14—H14A | 111.6 | C13'—C14'—H14C | 111.6 |
C8—C14—H14A | 111.6 | C8'—C14'—H14C | 111.6 |
C13—C14—H14B | 111.6 | C13'—C14'—H14D | 111.6 |
C8—C14—H14B | 111.6 | C8'—C14'—H14D | 111.6 |
H14A—C14—H14B | 109.4 | H14C—C14'—H14D | 109.4 |
O2—C15—C16 | 127.7 (3) | O2'—C15'—C16' | 126.9 (3) |
O2—C15—C8 | 126.1 (3) | O2'—C15'—C8' | 126.3 (3) |
C16—C15—C8 | 106.1 (3) | C16'—C15'—C8' | 106.8 (3) |
C17—C16—C15 | 122.3 (4) | C17'—C16'—C15' | 122.5 (3) |
C17—C16—C13 | 129.9 (4) | C17'—C16'—C13' | 130.2 (4) |
C15—C16—C13 | 107.8 (3) | C15'—C16'—C13' | 107.1 (3) |
C16—C17—H17A | 120.0 | C16'—C17'—H17C | 120.0 |
C16—C17—H17B | 120.0 | C16'—C17'—H17D | 120.0 |
H17A—C17—H17B | 120.0 | H17C—C17'—H17D | 120.0 |
C4—C18—H18A | 109.5 | C4'—C18'—H18D | 109.5 |
C4—C18—H18B | 109.5 | C4'—C18'—H18E | 109.5 |
H18A—C18—H18B | 109.5 | H18D—C18'—H18E | 109.5 |
C4—C18—H18C | 109.5 | C4'—C18'—H18F | 109.5 |
H18A—C18—H18C | 109.5 | H18D—C18'—H18F | 109.5 |
H18B—C18—H18C | 109.5 | H18E—C18'—H18F | 109.5 |
O5—C19—C4 | 106.2 (3) | O5'—C19'—C4' | 106.3 (3) |
O5—C19—H19A | 110.5 | O5'—C19'—H19C | 110.5 |
C4—C19—H19A | 110.5 | C4'—C19'—H19C | 110.5 |
O5—C19—H19B | 110.5 | O5'—C19'—H19D | 110.5 |
C4—C19—H19B | 110.5 | C4'—C19'—H19D | 110.5 |
H19A—C19—H19B | 108.7 | H19C—C19'—H19D | 108.7 |
O4—C20—C10 | 111.7 (2) | O4'—C20'—C10' | 112.0 (2) |
O4—C20—H20A | 109.3 | O4'—C20'—H20C | 109.2 |
C10—C20—H20A | 109.3 | C10'—C20'—H20C | 109.2 |
O4—C20—H20B | 109.3 | O4'—C20'—H20D | 109.2 |
C10—C20—H20B | 109.3 | C10'—C20'—H20D | 109.2 |
H20A—C20—H20B | 107.9 | H20C—C20'—H20D | 107.9 |
| | | |
C10—C1—C2—C3 | −60.1 (4) | C10'—C1'—C2'—C3' | −60.3 (4) |
C1—C2—C3—C4 | 59.7 (4) | C1'—C2'—C3'—C4' | 60.1 (4) |
C2—C3—C4—C19 | −159.9 (3) | C2'—C3'—C4'—C19' | −160.4 (3) |
C2—C3—C4—C18 | 80.3 (4) | C2'—C3'—C4'—C18' | 79.0 (4) |
C2—C3—C4—C5 | −52.0 (4) | C2'—C3'—C4'—C5' | −52.0 (4) |
C19—C4—C5—C6 | 34.6 (3) | C19'—C4'—C5'—C6' | 33.8 (3) |
C18—C4—C5—C6 | 151.7 (3) | C3'—C4'—C5'—C6' | −81.0 (3) |
C3—C4—C5—C6 | −79.5 (3) | C18'—C4'—C5'—C6' | 151.5 (3) |
C19—C4—C5—C10 | 161.6 (3) | C19'—C4'—C5'—C10' | 161.2 (3) |
C18—C4—C5—C10 | −81.3 (4) | C3'—C4'—C5'—C10' | 46.4 (4) |
C3—C4—C5—C10 | 47.5 (4) | C18'—C4'—C5'—C10' | −81.1 (4) |
C19—O5—C6—O6 | −176.6 (4) | C19'—O5'—C6'—O6' | −176.0 (4) |
C19—O5—C6—C5 | 3.3 (4) | C19'—O5'—C6'—C5' | 2.8 (4) |
C4—C5—C6—O6 | 154.6 (4) | C10'—C5'—C6'—O6' | 25.8 (6) |
C10—C5—C6—O6 | 26.6 (6) | C4'—C5'—C6'—O6' | 154.4 (4) |
C4—C5—C6—O5 | −25.2 (4) | C10'—C5'—C6'—O5' | −152.8 (3) |
C10—C5—C6—O5 | −153.2 (3) | C4'—C5'—C6'—O5' | −24.2 (4) |
C20—O4—C7—O3 | 177.4 (3) | C20'—O4'—C7'—O3' | 177.1 (3) |
C20—O4—C7—C8 | −6.9 (5) | C20'—O4'—C7'—C8' | −5.7 (4) |
O3—C7—C8—C15 | −35.4 (5) | O3'—C7'—C8'—C15' | −35.5 (5) |
O4—C7—C8—C15 | 149.1 (3) | O4'—C7'—C8'—C15' | 147.4 (3) |
O3—C7—C8—C14 | 74.1 (4) | O3'—C7'—C8'—C14' | 74.8 (4) |
O4—C7—C8—C14 | −101.3 (3) | O4'—C7'—C8'—C14' | −102.2 (3) |
O3—C7—C8—C9 | −157.5 (3) | O3'—C7'—C8'—C9' | −156.8 (3) |
O4—C7—C8—C9 | 27.1 (4) | O4'—C7'—C8'—C9' | 26.1 (4) |
C7—C8—C9—C11 | −131.1 (3) | C7'—C8'—C9'—C11' | −130.7 (3) |
C15—C8—C9—C11 | 102.9 (3) | C15'—C8'—C9'—C11' | 103.8 (3) |
C14—C8—C9—C11 | −3.6 (4) | C14'—C8'—C9'—C11' | −3.4 (3) |
C7—C8—C9—C10 | 2.1 (4) | C7'—C8'—C9'—C10' | 2.2 (4) |
C15—C8—C9—C10 | −123.9 (3) | C15'—C8'—C9'—C10' | −123.3 (3) |
C14—C8—C9—C10 | 129.6 (3) | C14'—C8'—C9'—C10' | 129.5 (3) |
C2—C1—C10—C20 | 172.9 (3) | C2'—C1'—C10'—C20' | 173.6 (3) |
C2—C1—C10—C9 | −70.1 (4) | C2'—C1'—C10'—C5' | 51.5 (4) |
C2—C1—C10—C5 | 51.6 (4) | C2'—C1'—C10'—C9' | −69.3 (4) |
C11—C9—C10—C20 | 84.9 (3) | C6'—C5'—C10'—C20' | −45.6 (4) |
C8—C9—C10—C20 | −44.7 (3) | C4'—C5'—C10'—C20' | −165.3 (3) |
C11—C9—C10—C1 | −32.5 (4) | C6'—C5'—C10'—C1' | 73.8 (3) |
C8—C9—C10—C1 | −162.1 (3) | C4'—C5'—C10'—C1' | −46.0 (4) |
C11—C9—C10—C5 | −154.1 (3) | C6'—C5'—C10'—C9' | −162.4 (3) |
C8—C9—C10—C5 | 76.3 (3) | C4'—C5'—C10'—C9' | 77.8 (3) |
C6—C5—C10—C20 | −45.3 (4) | C11'—C9'—C10'—C20' | 84.9 (3) |
C4—C5—C10—C20 | −165.1 (3) | C8'—C9'—C10'—C20' | −44.2 (3) |
C6—C5—C10—C1 | 72.9 (3) | C11'—C9'—C10'—C1' | −33.2 (4) |
C4—C5—C10—C1 | −46.9 (4) | C8'—C9'—C10'—C1' | −162.4 (3) |
C6—C5—C10—C9 | −162.8 (3) | C11'—C9'—C10'—C5' | −154.3 (3) |
C4—C5—C10—C9 | 77.5 (3) | C8'—C9'—C10'—C5' | 76.5 (3) |
C10—C9—C11—O1 | −58.3 (4) | C10'—C9'—C11'—O1' | −58.8 (4) |
C8—C9—C11—O1 | 70.9 (3) | C8'—C9'—C11'—O1' | 70.2 (3) |
C10—C9—C11—C12 | −179.6 (3) | C10'—C9'—C11'—C12' | 179.5 (3) |
C8—C9—C11—C12 | −50.4 (4) | C8'—C9'—C11'—C12' | −51.5 (3) |
O1—C11—C12—C13 | −80.4 (4) | O1'—C11'—C12'—C13' | −80.3 (3) |
C9—C11—C12—C13 | 42.6 (4) | C9'—C11'—C12'—C13' | 44.4 (4) |
C11—C12—C13—C16 | −91.7 (4) | C11'—C12'—C13'—C16' | −92.5 (4) |
C11—C12—C13—C14 | 19.7 (4) | C11'—C12'—C13'—C14' | 18.4 (4) |
C16—C13—C14—C8 | 46.6 (3) | C16'—C13'—C14'—C8' | 47.6 (3) |
C12—C13—C14—C8 | −72.1 (3) | C12'—C13'—C14'—C8' | −71.6 (3) |
C7—C8—C14—C13 | −165.1 (3) | C7'—C8'—C14'—C13' | −164.7 (2) |
C15—C8—C14—C13 | −46.9 (3) | C15'—C8'—C14'—C13' | −46.3 (3) |
C9—C8—C14—C13 | 62.9 (3) | C9'—C8'—C14'—C13' | 63.4 (3) |
C7—C8—C15—O2 | −37.8 (4) | C7'—C8'—C15'—O2' | −38.8 (4) |
C14—C8—C15—O2 | −153.5 (3) | C14'—C8'—C15'—O2' | −154.6 (3) |
C9—C8—C15—O2 | 91.4 (4) | C9'—C8'—C15'—O2' | 90.1 (4) |
C7—C8—C15—C16 | 145.6 (3) | C7'—C8'—C15'—C16' | 143.3 (3) |
C14—C8—C15—C16 | 29.9 (3) | C14'—C8'—C15'—C16' | 27.6 (3) |
C9—C8—C15—C16 | −85.2 (3) | C9'—C8'—C15'—C16' | −87.8 (3) |
O2—C15—C16—C17 | 2.7 (6) | O2'—C15'—C16'—C17' | 9.2 (6) |
C8—C15—C16—C17 | 179.2 (4) | C8'—C15'—C16'—C17' | −172.9 (3) |
O2—C15—C16—C13 | −178.0 (3) | O2'—C15'—C16'—C13' | −176.0 (3) |
C8—C15—C16—C13 | −1.5 (3) | C8'—C15'—C16'—C13' | 1.9 (3) |
C14—C13—C16—C17 | 151.1 (4) | C14'—C13'—C16'—C17' | 143.5 (4) |
C12—C13—C16—C17 | −92.1 (5) | C12'—C13'—C16'—C17' | −100.1 (5) |
C14—C13—C16—C15 | −28.1 (3) | C14'—C13'—C16'—C15' | −30.7 (3) |
C12—C13—C16—C15 | 88.7 (3) | C12'—C13'—C16'—C15' | 85.6 (3) |
C6—O5—C19—C4 | 20.8 (4) | C6'—O5'—C19'—C4' | 20.9 (4) |
C18—C4—C19—O5 | −158.1 (3) | C3'—C4'—C19'—O5' | 80.7 (3) |
C3—C4—C19—O5 | 80.7 (4) | C18'—C4'—C19'—O5' | −157.8 (3) |
C5—C4—C19—O5 | −34.5 (4) | C5'—C4'—C19'—O5' | −34.2 (4) |
C7—O4—C20—C10 | −41.5 (4) | C7'—O4'—C20'—C10' | −42.5 (4) |
C1—C10—C20—O4 | −171.2 (3) | C1'—C10'—C20'—O4' | −171.0 (3) |
C9—C10—C20—O4 | 67.2 (3) | C5'—C10'—C20'—O4' | −51.1 (4) |
C5—C10—C20—O4 | −51.8 (4) | C9'—C10'—C20'—O4' | 67.2 (3) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1A···O3i | 0.82 | 2.05 | 2.824 (4) | 157 |
O1′—H1′A···O3′ii | 0.82 | 2.07 | 2.856 (3) | 159 |
Symmetry codes: (i) x, y, z−1; (ii) x−1, y, z. |
Experimental details
Crystal data |
Chemical formula | C20H24O6 |
Mr | 360.39 |
Crystal system, space group | Monoclinic, P21 |
Temperature (K) | 291 |
a, b, c (Å) | 7.2397 (13), 36.724 (8), 7.304 (2) |
β (°) | 115.69 (2) |
V (Å3) | 1749.9 (7) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.52 × 0.44 × 0.42 |
|
Data collection |
Diffractometer | Siemens P4 diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3894, 3474, 2512 |
Rint | 0.017 |
(sin θ/λ)max (Å−1) | 0.617 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.038, 0.081, 0.91 |
No. of reflections | 3474 |
No. of parameters | 474 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.17, −0.14 |
Absolute structure | Flack (1983) |
Absolute structure parameter | −0.4 (11) |
Selected geometric parameters (Å, º) topO2—C15 | 1.207 (4) | O2'—C15' | 1.213 (4) |
O3—C7 | 1.210 (4) | O3'—C7' | 1.204 (4) |
O6—C6 | 1.193 (5) | O6'—C6' | 1.196 (5) |
C16—C17 | 1.310 (5) | C16'—C17' | 1.320 (5) |
| | | |
C20—C10—C9 | 106.4 (3) | C20'—C10'—C5' | 112.3 (3) |
C1—C10—C9 | 113.5 (3) | C1'—C10'—C5' | 108.9 (3) |
O1—C11—C9 | 111.7 (3) | O1'—C11'—C9' | 113.5 (3) |
| | | |
O2—C15—C16—C17 | 2.7 (6) | O2'—C15'—C16'—C17' | 9.2 (6) |
C8—C15—C16—C17 | 179.2 (4) | C8'—C15'—C16'—C17' | −172.9 (3) |
C14—C13—C16—C17 | 151.1 (4) | C14'—C13'—C16'—C17' | 143.5 (4) |
C12—C13—C16—C17 | −92.1 (5) | C12'—C13'—C16'—C17' | −100.1 (5) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1A···O3i | 0.82 | 2.05 | 2.824 (4) | 157.2 |
O1'—H1'A···O3'ii | 0.82 | 2.07 | 2.856 (3) | 159.2 |
Symmetry codes: (i) x, y, z−1; (ii) x−1, y, z. |
The diterpenoid ludongnin, (I), has been previously isolated from Rabdosia rubescens Hara (Ruan et al., 1986; Sun et al., 1988; Zheng et al., 1984, 1986) and its structure was established from the spectral and chemical evidence. Recently, it was for the first time isolated from Rabdosia var lophanthoides Hara, and its structure was confirmed by the X-ray diffraction study (Fig. 1).
In both molecules, the B ring adopts a chair, whereas the D ring shows a boat conformation. The isobenzofuran ring system couples orthogonally to the methanocyclohepta[c]pyran moiety through a spiro C atom. The differences in the geometrical parameters between two independent molecules are in fact inessential; the most notable discrepancies, as one would expect, have to do with the values of the torsion angles: C12—C13—C16—C17 - 92.1 (5), C12'-C13'-C16'-C17' -100.1 (5), C14—C13—C16—C17 151.1 (4) and C14'-C13'-C16'-C17' 143.5 (4)°.
The hydroxyl group of each of the independent molecules participates in the hydrogen bond with the carbonyl oxygen of the δ-lactone moiety of the same molecule as transformed by the c or a translation [O···O 2.824 (4) and 2.856 (3) Å, respectively]. Thus, two independent molecules give rise to two sets of infinite chains in the crystal, one of which is stretched along the z and another along the x axis of the crystal (Fig. 2).