The structures and absolute stereochemistries of two chamigrene-type metabolites (spiro[5.5]undecane derivatives) isolated from the red algae Laurencia scoparia are described. One, a non-sesquiterpene named mailione (8-bromo-9-hydroxy-7,7-dimethyl-11-methylenespiro[5.5]undec-1-en-3-one), C14H19BrO2, was detected previously in Laurencia cartilaginea, while the other, the sesquiterpene isorigidol (8-bromo-3,7,7-trimethyl-11-methylenespiro[5.5]-undec-1-ene-3,9-diol), C15H23BrO2, is a new isomer of rigidol, first isolated from Laurencia rigida. The A rings of these spirocyclic compounds show the same carbon skeleton. However, the relative stereochemistry of the 8-Br and 9-OH substituents is different. While mailione displays the usual syn (or cis) relative stereochemistry of the bromohydroxy vicinal group, isorigidol shows an anti (or trans) arrangement. The 8-Br and 9-OH groups are both in equatorial positions in isorigidol, while the 9-OH group is axial in mailione, as in most chamigrenes. The absolute configurations of the chiral centers were determined as 6S, 8S and 9R in mailione, and 3R, 6S, 8S and 9S in isorigidol.
Supporting information
CCDC references: 162566; 162567
The air-dried algae were extracted three times with dichloromethane over a
period of 1 d each time. Solvents were removed by evaporation at reduced
pressure. The residue was fractioned on silica gel 60 flash chromatography
column, with polarity-increasing mixtures of n-hexane–EtOAc–MeOH as eluent.
Some fractions were further purified using a Sephadex LH-20 column with
n-hexane–CHCl3–MeOH (1:1:1). The crude compounds were purified by
medium-pressure liquid chromatography on silica gel 100 with n-hexane–EtOAc
mixtures to obtain pure compounds. Compounds (IV) and (V) were
spectroscopically characterized before recrystallization. Single crystals of
maílione were obtained by slow evaporation of a mixture of
n-hexane–CH2Cl2 at room temperature, while single crystals of isorigidol
were obtained by slow evaporation of n-hexane at 268 (2) K.
In both compounds, all H atoms were clearly visible in difference maps and these
were then allowed for as riding atoms in the final refinement cycles, with
O—H = 0.82 Å and C—H in the range 0.93–0.98 Å. In the refinement of
(IV), there were 1765 unique reflections and 240 Friedel pairs; the
corresponding numbers in the refinement of (V) are 3919 and 606, respectively.
The values of the Flack parameters (see tabular material) establish
unequivocally the absolute configurations of (IV) and (V).
For both compounds, data collection: MSC/AFC Diffractometer Control Software (Molecular Structure Corporation, 1993); cell refinement: MSC/AFC Diffractometer Control Software; data reduction: MSC/AFC Diffractometer Control Software; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ZORTEP (Zsolnai & Pritzkow, 1995); software used to prepare material for publication: PLATON98 (Spek, 1990).
Crystal data top
C14H19BrO2 | Dx = 1.503 Mg m−3 |
Mr = 299.20 | Mo Kα radiation, λ = 0.71069 Å |
Orthorhombic, P212121 | Cell parameters from 24 reflections |
a = 9.9411 (16) Å | θ = 10.2–22.1° |
b = 18.0364 (14) Å | µ = 3.10 mm−1 |
c = 7.3758 (18) Å | T = 273 K |
V = 1322.5 (4) Å3 | Prism, colourless |
Z = 4 | 0.22 × 0.15 × 0.12 mm |
F(000) = 616 | |
Data collection top
Rigaku AFC-7S diffractometer | 1106 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.042 |
Graphite monochromator | θmax = 27.5°, θmin = 2.3° |
θ/2θ scans | h = −4→12 |
Absorption correction: y scan (North et al., 1968; Molecular Structure Corporation, 1993) | k = −17→23 |
Tmin = 0.549, Tmax = 0.708 | l = −7→9 |
2172 measured reflections | 3 standard reflections every 150 reflections |
2005 independent reflections | intensity decay: none |
Refinement top
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.044 | w = 1/[σ2(Fo2) + (0.0766P)2] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.128 | (Δ/σ)max < 0.001 |
S = 0.94 | Δρmax = 0.70 e Å−3 |
2005 reflections | Δρmin = −0.74 e Å−3 |
158 parameters | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
0 restraints | Extinction coefficient: 0.0053 (14) |
Primary atom site location: structure-invariant direct methods | Absolute structure: Flack (1983) |
Secondary atom site location: difference Fourier map | Absolute structure parameter: −0.03 (2) |
Crystal data top
C14H19BrO2 | V = 1322.5 (4) Å3 |
Mr = 299.20 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 9.9411 (16) Å | µ = 3.10 mm−1 |
b = 18.0364 (14) Å | T = 273 K |
c = 7.3758 (18) Å | 0.22 × 0.15 × 0.12 mm |
Data collection top
Rigaku AFC-7S diffractometer | 1106 reflections with I > 2σ(I) |
Absorption correction: y scan (North et al., 1968; Molecular Structure Corporation, 1993) | Rint = 0.042 |
Tmin = 0.549, Tmax = 0.708 | 3 standard reflections every 150 reflections |
2172 measured reflections | intensity decay: none |
2005 independent reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.044 | H-atom parameters constrained |
wR(F2) = 0.128 | Δρmax = 0.70 e Å−3 |
S = 0.94 | Δρmin = −0.74 e Å−3 |
2005 reflections | Absolute structure: Flack (1983) |
158 parameters | Absolute structure parameter: −0.03 (2) |
0 restraints | |
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 | |
Br8 | 0.05566 (9) | 0.34591 (4) | 0.13905 (10) | 0.0713 (3) | |
O3 | −0.0630 (6) | −0.0922 (3) | −0.1194 (7) | 0.0851 (16) | |
O9 | 0.0501 (7) | 0.2535 (2) | 0.5094 (6) | 0.0733 (16) | |
H9 | 0.0600 | 0.2984 | 0.5194 | 0.110* | |
C1 | 0.1285 (7) | 0.0459 (3) | 0.1051 (8) | 0.0520 (17) | |
H1 | 0.2181 | 0.0528 | 0.1374 | 0.062* | |
C2 | 0.0967 (9) | −0.0168 (4) | 0.0189 (9) | 0.063 (2) | |
H2 | 0.1655 | −0.0498 | −0.0092 | 0.076* | |
C3 | −0.0372 (9) | −0.0358 (4) | −0.0322 (8) | 0.061 (2) | |
C4 | −0.1442 (8) | 0.0159 (4) | 0.0287 (10) | 0.0599 (19) | |
H4A | −0.1733 | 0.0022 | 0.1497 | 0.072* | |
H4B | −0.2210 | 0.0120 | −0.0518 | 0.072* | |
C5 | −0.0934 (7) | 0.0960 (3) | 0.0300 (9) | 0.0540 (18) | |
H5A | −0.1649 | 0.1284 | 0.0715 | 0.065* | |
H5B | −0.0701 | 0.1106 | −0.0927 | 0.065* | |
C6 | 0.0305 (6) | 0.1060 (3) | 0.1536 (8) | 0.0438 (15) | |
C7 | 0.0991 (6) | 0.1854 (3) | 0.1231 (8) | 0.0442 (15) | |
C71 | 0.1309 (9) | 0.1966 (4) | −0.0788 (9) | 0.065 (2) | |
H71A | 0.1913 | 0.2378 | −0.0926 | 0.098* | |
H71B | 0.0491 | 0.2065 | −0.1437 | 0.098* | |
H71C | 0.1721 | 0.1526 | −0.1264 | 0.098* | |
C72 | 0.2312 (8) | 0.1901 (4) | 0.2275 (11) | 0.062 (2) | |
H72A | 0.2656 | 0.2397 | 0.2212 | 0.093* | |
H72B | 0.2953 | 0.1565 | 0.1752 | 0.093* | |
H72C | 0.2160 | 0.1769 | 0.3520 | 0.093* | |
C8 | −0.0046 (7) | 0.2432 (4) | 0.1848 (7) | 0.0489 (18) | |
H8 | −0.0846 | 0.2356 | 0.1096 | 0.059* | |
C9 | −0.0516 (8) | 0.2386 (3) | 0.3813 (8) | 0.0559 (17) | |
H9A | −0.1253 | 0.2739 | 0.3994 | 0.067* | |
C10 | −0.1037 (8) | 0.1606 (3) | 0.4162 (9) | 0.0600 (18) | |
H10A | −0.1188 | 0.1547 | 0.5453 | 0.072* | |
H10B | −0.1897 | 0.1549 | 0.3558 | 0.072* | |
C11 | −0.0116 (7) | 0.1003 (3) | 0.3532 (9) | 0.0473 (16) | |
C12 | 0.0263 (8) | 0.0448 (4) | 0.4605 (9) | 0.065 (2) | |
H12A | −0.0046 | 0.0425 | 0.5794 | 0.078* | |
H12B | 0.0837 | 0.0082 | 0.4166 | 0.078* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Br8 | 0.1013 (6) | 0.0493 (4) | 0.0632 (4) | −0.0078 (4) | −0.0029 (5) | 0.0114 (4) |
O3 | 0.124 (5) | 0.063 (3) | 0.069 (3) | −0.017 (3) | −0.012 (4) | −0.014 (3) |
O9 | 0.124 (5) | 0.048 (2) | 0.047 (2) | 0.004 (4) | −0.016 (3) | −0.001 (2) |
C1 | 0.053 (4) | 0.057 (4) | 0.046 (4) | 0.011 (4) | 0.003 (4) | −0.005 (3) |
C2 | 0.074 (6) | 0.057 (4) | 0.059 (4) | 0.003 (4) | 0.003 (4) | −0.007 (4) |
C3 | 0.093 (6) | 0.048 (4) | 0.042 (3) | −0.024 (5) | −0.011 (4) | −0.005 (3) |
C4 | 0.057 (5) | 0.062 (4) | 0.061 (4) | −0.012 (4) | −0.005 (4) | −0.006 (4) |
C5 | 0.057 (5) | 0.050 (3) | 0.055 (4) | −0.002 (3) | −0.010 (4) | −0.006 (3) |
C6 | 0.049 (4) | 0.045 (3) | 0.038 (3) | 0.001 (3) | 0.002 (4) | −0.002 (3) |
C7 | 0.044 (4) | 0.054 (3) | 0.035 (3) | −0.005 (3) | −0.002 (3) | 0.005 (3) |
C71 | 0.084 (6) | 0.069 (4) | 0.043 (3) | −0.008 (5) | 0.015 (4) | −0.005 (3) |
C72 | 0.062 (5) | 0.057 (4) | 0.066 (4) | −0.013 (4) | −0.009 (4) | −0.002 (4) |
C8 | 0.055 (4) | 0.055 (4) | 0.037 (3) | 0.007 (3) | −0.004 (3) | 0.001 (3) |
C9 | 0.073 (5) | 0.042 (3) | 0.053 (4) | 0.006 (4) | 0.012 (5) | 0.004 (3) |
C10 | 0.074 (5) | 0.053 (4) | 0.053 (3) | 0.003 (4) | 0.021 (4) | −0.003 (3) |
C11 | 0.061 (4) | 0.043 (3) | 0.037 (3) | −0.010 (3) | −0.009 (4) | 0.002 (3) |
C12 | 0.090 (6) | 0.056 (4) | 0.051 (4) | −0.010 (4) | −0.005 (4) | 0.005 (3) |
Geometric parameters (Å, º) top
Br8—C8 | 1.975 (7) | C7—C8 | 1.535 (9) |
O3—C3 | 1.231 (7) | C7—C71 | 1.536 (9) |
O9—C9 | 1.409 (8) | C71—H71A | 0.96 |
O9—H9 | 0.82 | C71—H71B | 0.96 |
C1—C2 | 1.335 (9) | C71—H71C | 0.96 |
C1—C6 | 1.501 (9) | C72—H72A | 0.96 |
C1—H1 | 0.93 | C72—H72B | 0.96 |
C2—C3 | 1.426 (11) | C72—H72C | 0.96 |
C2—H2 | 0.93 | C8—C9 | 1.525 (8) |
C3—C4 | 1.484 (10) | C8—H8 | 0.98 |
C4—C5 | 1.531 (9) | C9—C10 | 1.522 (9) |
C4—H4A | 0.97 | C9—H9A | 0.98 |
C4—H4B | 0.97 | C10—C11 | 1.495 (9) |
C5—C6 | 1.543 (9) | C10—H10A | 0.97 |
C5—H5A | 0.97 | C10—H10B | 0.97 |
C5—H5B | 0.97 | C11—C12 | 1.332 (9) |
C6—C11 | 1.534 (9) | C12—H12A | 0.93 |
C6—C7 | 1.602 (9) | C12—H12B | 0.93 |
C7—C72 | 1.525 (10) | | |
| | | |
C9—O9—H9 | 109.5 | C7—C71—H71B | 109.5 |
C2—C1—C6 | 124.9 (7) | H71A—C71—H71B | 109.5 |
C2—C1—H1 | 117.6 | C7—C71—H71C | 109.5 |
C6—C1—H1 | 117.6 | H71A—C71—H71C | 109.5 |
C1—C2—C3 | 123.4 (8) | H71B—C71—H71C | 109.5 |
C1—C2—H2 | 118.3 | C7—C72—H72A | 109.5 |
C3—C2—H2 | 118.3 | C7—C72—H72B | 109.5 |
O3—C3—C2 | 122.1 (8) | H72A—C72—H72B | 109.5 |
O3—C3—C4 | 121.9 (8) | C7—C72—H72C | 109.5 |
C2—C3—C4 | 115.9 (5) | H72A—C72—H72C | 109.5 |
C3—C4—C5 | 111.0 (6) | H72B—C72—H72C | 109.5 |
C3—C4—H4A | 109.4 | C9—C8—C7 | 116.7 (5) |
C5—C4—H4A | 109.4 | C9—C8—Br8 | 107.8 (4) |
C3—C4—H4B | 109.4 | C7—C8—Br8 | 112.5 (4) |
C5—C4—H4B | 109.4 | C9—C8—H8 | 106.4 |
H4A—C4—H4B | 108.0 | C7—C8—H8 | 106.4 |
C4—C5—C6 | 112.2 (6) | Br8—C8—H8 | 106.4 |
C4—C5—H5A | 109.2 | O9—C9—C10 | 107.8 (5) |
C6—C5—H5A | 109.2 | O9—C9—C8 | 114.0 (6) |
C4—C5—H5B | 109.2 | C10—C9—C8 | 108.4 (5) |
C6—C5—H5B | 109.2 | O9—C9—H9A | 108.8 |
H5A—C5—H5B | 107.9 | C10—C9—H9A | 108.8 |
C1—C6—C11 | 111.0 (5) | C8—C9—H9A | 108.8 |
C1—C6—C5 | 107.0 (5) | C11—C10—C9 | 114.3 (6) |
C11—C6—C5 | 109.9 (5) | C11—C10—H10A | 108.7 |
C1—C6—C7 | 109.7 (5) | C9—C10—H10A | 108.7 |
C11—C6—C7 | 108.1 (5) | C11—C10—H10B | 108.7 |
C5—C6—C7 | 111.2 (5) | C9—C10—H10B | 108.7 |
C72—C7—C8 | 113.0 (5) | H10A—C10—H10B | 107.6 |
C72—C7—C71 | 107.8 (6) | C12—C11—C10 | 122.4 (6) |
C8—C7—C71 | 109.6 (5) | C12—C11—C6 | 122.9 (6) |
C72—C7—C6 | 110.2 (5) | C10—C11—C6 | 114.6 (5) |
C8—C7—C6 | 106.3 (5) | C11—C12—H12A | 120.0 |
C71—C7—C6 | 110.0 (5) | C11—C12—H12B | 120.0 |
C7—C71—H71A | 109.5 | H12A—C12—H12B | 120.0 |
| | | |
C6—C1—C2—C3 | −2.5 (10) | C72—C7—C8—C9 | −61.7 (8) |
C1—C2—C3—O3 | 176.3 (6) | C71—C7—C8—C9 | 178.0 (6) |
C1—C2—C3—C4 | −4.6 (10) | C6—C7—C8—C9 | 59.2 (7) |
O3—C3—C4—C5 | −146.7 (6) | C72—C7—C8—Br8 | 63.7 (6) |
C2—C3—C4—C5 | 34.2 (8) | C71—C7—C8—Br8 | −56.5 (6) |
C3—C4—C5—C6 | −58.2 (7) | C6—C7—C8—Br8 | −175.3 (4) |
C2—C1—C6—C11 | 99.9 (7) | C7—C8—C9—O9 | 65.6 (7) |
C2—C1—C6—C5 | −20.1 (9) | Br8—C8—C9—O9 | −62.2 (6) |
C2—C1—C6—C7 | −140.8 (6) | C7—C8—C9—C10 | −54.5 (8) |
C4—C5—C6—C1 | 49.1 (7) | Br8—C8—C9—C10 | 177.7 (5) |
C4—C5—C6—C11 | −71.5 (7) | O9—C9—C10—C11 | −75.4 (7) |
C4—C5—C6—C7 | 168.8 (6) | C8—C9—C10—C11 | 48.5 (8) |
C1—C6—C7—C72 | −54.4 (7) | C9—C10—C11—C12 | 128.6 (7) |
C11—C6—C7—C72 | 66.7 (7) | C9—C10—C11—C6 | −53.9 (8) |
C5—C6—C7—C72 | −172.5 (5) | C1—C6—C11—C12 | −5.6 (9) |
C1—C6—C7—C8 | −177.2 (5) | C5—C6—C11—C12 | 112.7 (7) |
C11—C6—C7—C8 | −56.1 (6) | C7—C6—C11—C12 | −125.8 (6) |
C5—C6—C7—C8 | 64.7 (6) | C1—C6—C11—C10 | 176.9 (6) |
C1—C6—C7—C71 | 64.3 (7) | C5—C6—C11—C10 | −64.9 (7) |
C11—C6—C7—C71 | −174.7 (5) | C7—C6—C11—C10 | 56.6 (7) |
C5—C6—C7—C71 | −53.9 (7) | | |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O9—H9···O3i | 0.82 | 2.11 | 2.902 (7) | 164 |
Symmetry code: (i) x+1/2, −y+1/2, −z. |
Crystal data top
C15H23BrO2 | Dx = 1.374 Mg m−3 |
Mr = 315.25 | Mo Kα radiation, λ = 0.71069 Å |
Orthorhombic, P212121 | Cell parameters from 25 reflections |
a = 11.872 (5) Å | θ = 7.5–11.4° |
b = 11.897 (4) Å | µ = 2.69 mm−1 |
c = 21.575 (4) Å | T = 273 K |
V = 3047.2 (17) Å3 | Parallelepiped, colourless |
Z = 8 | 0.23 × 0.17 × 0.13 mm |
F(000) = 1312 | |
Data collection top
Rigaku AFC-7S diffractometer | 2442 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.029 |
Graphite monochromator | θmax = 27.5°, θmin = 2.4° |
θ/2θ scans | h = −1→15 |
Absorption correction: ψ scan (North et al., 1968; Molecular Structure Corporation, 1993) | k = −1→15 |
Tmin = 0.577, Tmax = 0.721 | l = 0→28 |
4662 measured reflections | 3 standard reflections every 150 reflections |
4525 independent reflections | intensity decay: none |
Refinement top
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.034 | w = 1/[σ2(Fo2) + (0.0373P)2] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.094 | (Δ/σ)max = 0.001 |
S = 0.94 | Δρmax = 0.42 e Å−3 |
4525 reflections | Δρmin = −0.60 e Å−3 |
336 parameters | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
0 restraints | Extinction coefficient: 0.0032 (3) |
Primary atom site location: structure-invariant direct methods | Absolute structure: Flack (1983) |
Secondary atom site location: difference Fourier map | Absolute structure parameter: −0.011 (11) |
Crystal data top
C15H23BrO2 | V = 3047.2 (17) Å3 |
Mr = 315.25 | Z = 8 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 11.872 (5) Å | µ = 2.69 mm−1 |
b = 11.897 (4) Å | T = 273 K |
c = 21.575 (4) Å | 0.23 × 0.17 × 0.13 mm |
Data collection top
Rigaku AFC-7S diffractometer | 2442 reflections with I > 2σ(I) |
Absorption correction: ψ scan (North et al., 1968; Molecular Structure Corporation, 1993) | Rint = 0.029 |
Tmin = 0.577, Tmax = 0.721 | 3 standard reflections every 150 reflections |
4662 measured reflections | intensity decay: none |
4525 independent reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.034 | H-atom parameters constrained |
wR(F2) = 0.094 | Δρmax = 0.42 e Å−3 |
S = 0.94 | Δρmin = −0.60 e Å−3 |
4525 reflections | Absolute structure: Flack (1983) |
336 parameters | Absolute structure parameter: −0.011 (11) |
0 restraints | |
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 | |
Br8A | 0.58034 (5) | 0.47646 (5) | 0.53216 (3) | 0.05415 (18) | |
O3A | 0.4047 (3) | 1.0610 (3) | 0.62965 (18) | 0.0606 (11) | |
H3A | 0.3891 | 0.9966 | 0.6403 | 0.091* | |
O9A | 0.6136 (3) | 0.6019 (3) | 0.40352 (15) | 0.0513 (10) | |
H9A | 0.6338 | 0.5360 | 0.4037 | 0.077* | |
C1A | 0.6465 (4) | 0.9110 (4) | 0.6057 (2) | 0.0428 (13) | |
H1A | 0.7082 | 0.8875 | 0.6289 | 0.051* | |
C2A | 0.5969 (4) | 1.0066 (4) | 0.6217 (2) | 0.0446 (14) | |
H2A | 0.6250 | 1.0439 | 0.6564 | 0.053* | |
C3A | 0.5005 (4) | 1.0589 (4) | 0.5890 (2) | 0.0425 (13) | |
C31A | 0.5238 (6) | 1.1842 (4) | 0.5752 (3) | 0.0680 (18) | |
H31A | 0.4624 | 1.2148 | 0.5517 | 0.102* | |
H31B | 0.5922 | 1.1909 | 0.5518 | 0.102* | |
H31C | 0.5312 | 1.2246 | 0.6135 | 0.102* | |
C4A | 0.4739 (4) | 0.9967 (4) | 0.5284 (2) | 0.0439 (13) | |
H4A | 0.3975 | 1.0138 | 0.5156 | 0.053* | |
H4B | 0.5247 | 1.0221 | 0.4961 | 0.053* | |
C5A | 0.4866 (4) | 0.8702 (4) | 0.5372 (2) | 0.0359 (11) | |
H5A | 0.4628 | 0.8320 | 0.4997 | 0.043* | |
H5B | 0.4381 | 0.8457 | 0.5707 | 0.043* | |
C6A | 0.6094 (4) | 0.8373 (4) | 0.5520 (2) | 0.0323 (11) | |
C7A | 0.6196 (4) | 0.7094 (4) | 0.57085 (19) | 0.0362 (12) | |
C71A | 0.5430 (5) | 0.6826 (5) | 0.6264 (2) | 0.0523 (15) | |
H71A | 0.5602 | 0.6088 | 0.6418 | 0.078* | |
H71B | 0.4656 | 0.6852 | 0.6135 | 0.078* | |
H71C | 0.5553 | 0.7369 | 0.6586 | 0.078* | |
C72A | 0.7412 (4) | 0.6803 (5) | 0.5899 (2) | 0.0508 (15) | |
H72A | 0.7558 | 0.7091 | 0.6307 | 0.076* | |
H72B | 0.7929 | 0.7135 | 0.5610 | 0.076* | |
H72C | 0.7507 | 0.6002 | 0.5899 | 0.076* | |
C8A | 0.5832 (5) | 0.6394 (4) | 0.51380 (19) | 0.0387 (12) | |
H8A | 0.5065 | 0.6621 | 0.5028 | 0.046* | |
C9A | 0.6568 (4) | 0.6577 (4) | 0.4577 (2) | 0.0396 (12) | |
H9C | 0.7338 | 0.6324 | 0.4662 | 0.047* | |
C10A | 0.6567 (5) | 0.7810 (4) | 0.4408 (2) | 0.0487 (14) | |
H10A | 0.5832 | 0.8008 | 0.4245 | 0.058* | |
H10B | 0.7117 | 0.7937 | 0.4083 | 0.058* | |
C11A | 0.6835 (4) | 0.8573 (4) | 0.4952 (2) | 0.0417 (13) | |
C12A | 0.7624 (5) | 0.9339 (5) | 0.4917 (3) | 0.0620 (17) | |
H12A | 0.8034 | 0.9425 | 0.4552 | 0.074* | |
H12B | 0.7774 | 0.9798 | 0.5256 | 0.074* | |
Br8B | 0.79350 (5) | 0.20618 (6) | 0.28625 (3) | 0.0665 (2) | |
O9B | 0.6791 (3) | 0.3822 (3) | 0.3761 (2) | 0.0606 (11) | |
H9B | 0.7452 | 0.3751 | 0.3659 | 0.091* | |
O3B | 0.1961 (3) | 0.1328 (4) | 0.17553 (13) | 0.0518 (10) | |
H3B | 0.2581 | 0.1164 | 0.1615 | 0.078* | |
C1B | 0.3628 (4) | 0.0498 (4) | 0.2968 (2) | 0.0405 (13) | |
H1B | 0.3908 | −0.0166 | 0.3135 | 0.049* | |
C2B | 0.2651 (4) | 0.0448 (4) | 0.2689 (2) | 0.0414 (13) | |
H2B | 0.2315 | −0.0254 | 0.2649 | 0.050* | |
C3B | 0.2037 (4) | 0.1436 (5) | 0.2432 (2) | 0.0449 (13) | |
C31B | 0.0816 (4) | 0.1442 (6) | 0.2649 (2) | 0.0638 (17) | |
H31D | 0.0459 | 0.2126 | 0.2517 | 0.096* | |
H31E | 0.0793 | 0.1393 | 0.3093 | 0.096* | |
H31F | 0.0426 | 0.0811 | 0.2473 | 0.096* | |
C4B | 0.2624 (4) | 0.2528 (5) | 0.2597 (2) | 0.0449 (14) | |
H4C | 0.2414 | 0.2749 | 0.3014 | 0.054* | |
H4D | 0.2382 | 0.3115 | 0.2316 | 0.054* | |
C5B | 0.3908 (4) | 0.2400 (4) | 0.2559 (2) | 0.0384 (12) | |
H5C | 0.4261 | 0.3123 | 0.2634 | 0.046* | |
H5D | 0.4117 | 0.2155 | 0.2146 | 0.046* | |
C6B | 0.4339 (4) | 0.1537 (4) | 0.30408 (19) | 0.0322 (11) | |
C7B | 0.5630 (4) | 0.1234 (4) | 0.2932 (2) | 0.0365 (11) | |
C71B | 0.5808 (5) | 0.0801 (4) | 0.2262 (2) | 0.0471 (13) | |
H71D | 0.6536 | 0.0452 | 0.2230 | 0.071* | |
H71E | 0.5766 | 0.1420 | 0.1977 | 0.071* | |
H71F | 0.5235 | 0.0261 | 0.2162 | 0.071* | |
C72B | 0.5992 (4) | 0.0296 (4) | 0.3382 (2) | 0.0484 (13) | |
H72D | 0.6799 | 0.0260 | 0.3398 | 0.073* | |
H72E | 0.5700 | −0.0411 | 0.3240 | 0.073* | |
H72F | 0.5703 | 0.0454 | 0.3788 | 0.073* | |
C8B | 0.6325 (4) | 0.2310 (4) | 0.3044 (2) | 0.0405 (12) | |
H8B | 0.6048 | 0.2889 | 0.2759 | 0.049* | |
C9B | 0.6225 (4) | 0.2765 (5) | 0.3699 (2) | 0.0443 (13) | |
H9D | 0.6524 | 0.2222 | 0.3998 | 0.053* | |
C10B | 0.4989 (4) | 0.3010 (5) | 0.3835 (2) | 0.0464 (14) | |
H10C | 0.4912 | 0.3200 | 0.4271 | 0.056* | |
H10D | 0.4757 | 0.3660 | 0.3596 | 0.056* | |
C11B | 0.4211 (4) | 0.2042 (4) | 0.36888 (19) | 0.0373 (11) | |
C12B | 0.3443 (4) | 0.1731 (5) | 0.4090 (2) | 0.0545 (16) | |
H12C | 0.3377 | 0.2107 | 0.4467 | 0.065* | |
H12D | 0.2965 | 0.1135 | 0.3999 | 0.065* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Br8A | 0.0738 (4) | 0.0342 (3) | 0.0544 (3) | 0.0041 (3) | −0.0034 (3) | 0.0022 (3) |
O3A | 0.056 (3) | 0.055 (2) | 0.071 (3) | 0.018 (2) | 0.017 (2) | −0.003 (2) |
O9A | 0.066 (3) | 0.051 (2) | 0.0367 (18) | −0.003 (2) | −0.0029 (19) | −0.0173 (18) |
C1A | 0.035 (3) | 0.046 (3) | 0.047 (3) | 0.003 (3) | −0.006 (3) | −0.008 (3) |
C2A | 0.042 (3) | 0.045 (3) | 0.047 (3) | −0.002 (3) | 0.001 (3) | −0.014 (2) |
C3A | 0.044 (3) | 0.029 (3) | 0.054 (3) | 0.006 (3) | 0.010 (3) | 0.000 (3) |
C31A | 0.086 (5) | 0.034 (3) | 0.084 (4) | −0.006 (4) | −0.005 (4) | −0.002 (3) |
C4A | 0.042 (3) | 0.043 (3) | 0.047 (3) | 0.010 (3) | −0.005 (3) | 0.000 (3) |
C5A | 0.037 (3) | 0.030 (3) | 0.041 (3) | 0.001 (2) | −0.006 (2) | −0.009 (3) |
C6A | 0.031 (3) | 0.031 (3) | 0.036 (2) | −0.003 (2) | −0.002 (2) | −0.005 (2) |
C7A | 0.038 (3) | 0.044 (3) | 0.027 (2) | 0.008 (3) | −0.004 (2) | 0.002 (2) |
C71A | 0.070 (4) | 0.049 (3) | 0.038 (3) | 0.000 (3) | 0.006 (3) | −0.003 (3) |
C72A | 0.051 (3) | 0.056 (4) | 0.046 (3) | 0.022 (3) | −0.015 (3) | −0.007 (3) |
C8A | 0.047 (3) | 0.032 (3) | 0.037 (3) | 0.002 (3) | 0.002 (2) | 0.001 (2) |
C9A | 0.037 (3) | 0.044 (3) | 0.038 (3) | 0.000 (3) | 0.004 (2) | −0.012 (2) |
C10A | 0.071 (4) | 0.041 (3) | 0.034 (2) | −0.007 (3) | 0.014 (3) | −0.002 (2) |
C11A | 0.039 (3) | 0.034 (3) | 0.051 (3) | 0.001 (3) | 0.007 (2) | −0.002 (3) |
C12A | 0.059 (4) | 0.056 (4) | 0.071 (4) | −0.012 (4) | 0.018 (3) | −0.011 (3) |
Br8B | 0.0401 (3) | 0.0769 (5) | 0.0825 (4) | −0.0080 (4) | 0.0145 (3) | −0.0286 (4) |
O9B | 0.047 (2) | 0.052 (2) | 0.083 (3) | −0.022 (2) | 0.018 (2) | −0.031 (2) |
O3B | 0.045 (2) | 0.077 (3) | 0.0330 (17) | −0.002 (2) | −0.0003 (17) | −0.0043 (19) |
C1B | 0.048 (3) | 0.033 (3) | 0.041 (3) | −0.010 (3) | −0.006 (3) | 0.009 (2) |
C2B | 0.047 (3) | 0.039 (3) | 0.038 (3) | −0.012 (3) | −0.001 (2) | −0.003 (2) |
C3B | 0.038 (3) | 0.063 (4) | 0.033 (3) | −0.002 (3) | 0.000 (2) | −0.008 (3) |
C31B | 0.041 (3) | 0.100 (5) | 0.051 (3) | 0.000 (4) | 0.009 (3) | −0.007 (3) |
C4B | 0.044 (3) | 0.045 (3) | 0.046 (3) | 0.007 (3) | −0.006 (2) | 0.003 (3) |
C5B | 0.042 (3) | 0.034 (3) | 0.039 (2) | 0.000 (3) | −0.007 (2) | 0.005 (2) |
C6B | 0.036 (3) | 0.026 (2) | 0.035 (2) | −0.009 (2) | −0.001 (2) | 0.006 (2) |
C7B | 0.042 (3) | 0.028 (2) | 0.040 (3) | −0.002 (2) | 0.000 (2) | −0.004 (2) |
C71B | 0.056 (3) | 0.042 (3) | 0.043 (3) | 0.003 (3) | 0.007 (3) | −0.009 (2) |
C72B | 0.052 (3) | 0.037 (3) | 0.057 (3) | 0.007 (3) | −0.013 (3) | 0.004 (3) |
C8B | 0.037 (3) | 0.038 (3) | 0.047 (3) | −0.005 (3) | 0.007 (2) | −0.008 (2) |
C9B | 0.038 (3) | 0.047 (3) | 0.049 (3) | −0.004 (3) | −0.001 (2) | −0.013 (3) |
C10B | 0.047 (3) | 0.054 (4) | 0.038 (3) | −0.018 (3) | 0.012 (2) | −0.016 (3) |
C11B | 0.037 (3) | 0.037 (3) | 0.037 (2) | −0.004 (3) | 0.002 (2) | 0.002 (2) |
C12B | 0.056 (3) | 0.067 (4) | 0.041 (3) | −0.023 (3) | 0.008 (3) | −0.001 (3) |
Geometric parameters (Å, º) top
Br8A—C8A | 1.978 (5) | Br8B—C8B | 1.973 (5) |
O3A—C3A | 1.437 (6) | O9B—C9B | 1.432 (6) |
O3A—H3A | 0.82 | O9B—H9B | 0.82 |
O9A—C9A | 1.438 (5) | O3B—C3B | 1.468 (5) |
O9A—H9A | 0.82 | O3B—H3B | 0.82 |
C1A—C2A | 1.327 (7) | C1B—C2B | 1.308 (7) |
C1A—C6A | 1.517 (6) | C1B—C6B | 1.505 (6) |
C1A—H1A | 0.93 | C1B—H1B | 0.93 |
C2A—C3A | 1.482 (7) | C2B—C3B | 1.490 (7) |
C2A—H2A | 0.93 | C2B—H2B | 0.93 |
C3A—C4A | 1.535 (7) | C3B—C4B | 1.517 (7) |
C3A—C31A | 1.544 (7) | C3B—C31B | 1.524 (7) |
C31A—H31A | 0.96 | C31B—H31D | 0.96 |
C31A—H31B | 0.96 | C31B—H31E | 0.96 |
C31A—H31C | 0.96 | C31B—H31F | 0.96 |
C4A—C5A | 1.525 (6) | C4B—C5B | 1.534 (7) |
C4A—H4A | 0.97 | C4B—H4C | 0.97 |
C4A—H4B | 0.97 | C4B—H4D | 0.97 |
C5A—C6A | 1.543 (6) | C5B—C6B | 1.547 (6) |
C5A—H5A | 0.97 | C5B—H5C | 0.97 |
C5A—H5B | 0.97 | C5B—H5D | 0.97 |
C6A—C11A | 1.527 (6) | C6B—C11B | 1.529 (6) |
C6A—C7A | 1.580 (7) | C6B—C7B | 1.593 (7) |
C7A—C71A | 1.538 (6) | C7B—C72B | 1.540 (6) |
C7A—C72A | 1.541 (7) | C7B—C8B | 1.542 (6) |
C7A—C8A | 1.548 (6) | C7B—C71B | 1.549 (6) |
C71A—H71A | 0.96 | C71B—H71D | 0.96 |
C71A—H71B | 0.96 | C71B—H71E | 0.96 |
C71A—H71C | 0.96 | C71B—H71F | 0.96 |
C72A—H72A | 0.96 | C72B—H72D | 0.96 |
C72A—H72B | 0.96 | C72B—H72E | 0.96 |
C72A—H72C | 0.96 | C72B—H72F | 0.96 |
C8A—C9A | 1.509 (6) | C8B—C9B | 1.518 (6) |
C8A—H8A | 0.98 | C8B—H8B | 0.98 |
C9A—C10A | 1.512 (7) | C9B—C10B | 1.524 (7) |
C9A—H9C | 0.98 | C9B—H9D | 0.98 |
C10A—C11A | 1.518 (7) | C10B—C11B | 1.509 (7) |
C10A—H10A | 0.97 | C10B—H10C | 0.97 |
C10A—H10B | 0.97 | C10B—H10D | 0.97 |
C11A—C12A | 1.309 (7) | C11B—C12B | 1.311 (6) |
C12A—H12A | 0.93 | C12B—H12C | 0.93 |
C12A—H12B | 0.93 | C12B—H12D | 0.93 |
| | | |
C3A—O3A—H3A | 109.5 | C9B—O9B—H9B | 109.5 |
C9A—O9A—H9A | 109.5 | C3B—O3B—H3B | 109.5 |
C2A—C1A—C6A | 124.4 (5) | C2B—C1B—C6B | 125.6 (5) |
C2A—C1A—H1A | 117.8 | C2B—C1B—H1B | 117.2 |
C6A—C1A—H1A | 117.8 | C6B—C1B—H1B | 117.2 |
C1A—C2A—C3A | 125.3 (5) | C1B—C2B—C3B | 124.7 (5) |
C1A—C2A—H2A | 117.3 | C1B—C2B—H2B | 117.6 |
C3A—C2A—H2A | 117.3 | C3B—C2B—H2B | 117.6 |
O3A—C3A—C2A | 109.2 (4) | O3B—C3B—C2B | 109.4 (4) |
O3A—C3A—C4A | 111.4 (4) | O3B—C3B—C4B | 109.7 (5) |
C2A—C3A—C4A | 111.2 (4) | C2B—C3B—C4B | 111.3 (4) |
O3A—C3A—C31A | 104.1 (4) | O3B—C3B—C31B | 104.3 (4) |
C2A—C3A—C31A | 111.1 (5) | C2B—C3B—C31B | 110.8 (5) |
C4A—C3A—C31A | 109.7 (4) | C4B—C3B—C31B | 111.1 (5) |
C3A—C31A—H31A | 109.5 | C3B—C31B—H31D | 109.5 |
C3A—C31A—H31B | 109.5 | C3B—C31B—H31E | 109.5 |
H31A—C31A—H31B | 109.5 | H31D—C31B—H31E | 109.5 |
C3A—C31A—H31C | 109.5 | C3B—C31B—H31F | 109.5 |
H31A—C31A—H31C | 109.5 | H31D—C31B—H31F | 109.5 |
H31B—C31A—H31C | 109.5 | H31E—C31B—H31F | 109.5 |
C5A—C4A—C3A | 110.5 (4) | C3B—C4B—C5B | 111.0 (4) |
C5A—C4A—H4A | 109.5 | C3B—C4B—H4C | 109.4 |
C3A—C4A—H4A | 109.5 | C5B—C4B—H4C | 109.4 |
C5A—C4A—H4B | 109.5 | C3B—C4B—H4D | 109.4 |
C3A—C4A—H4B | 109.5 | C5B—C4B—H4D | 109.4 |
H4A—C4A—H4B | 108.1 | H4C—C4B—H4D | 108.0 |
C4A—C5A—C6A | 111.7 (4) | C4B—C5B—C6B | 111.0 (4) |
C4A—C5A—H5A | 109.3 | C4B—C5B—H5C | 109.4 |
C6A—C5A—H5A | 109.3 | C6B—C5B—H5C | 109.4 |
C4A—C5A—H5B | 109.3 | C4B—C5B—H5D | 109.4 |
C6A—C5A—H5B | 109.3 | C6B—C5B—H5D | 109.4 |
H5A—C5A—H5B | 107.9 | H5C—C5B—H5D | 108.0 |
C1A—C6A—C11A | 110.8 (4) | C1B—C6B—C11B | 111.3 (4) |
C1A—C6A—C5A | 106.7 (4) | C1B—C6B—C5B | 106.9 (4) |
C11A—C6A—C5A | 109.8 (4) | C11B—C6B—C5B | 108.7 (4) |
C1A—C6A—C7A | 109.8 (4) | C1B—C6B—C7B | 109.7 (4) |
C11A—C6A—C7A | 108.2 (4) | C11B—C6B—C7B | 108.6 (4) |
C5A—C6A—C7A | 111.7 (4) | C5B—C6B—C7B | 111.7 (4) |
C71A—C7A—C72A | 107.4 (4) | C72B—C7B—C8B | 110.7 (4) |
C71A—C7A—C8A | 110.1 (4) | C72B—C7B—C71B | 108.0 (4) |
C72A—C7A—C8A | 110.6 (4) | C8B—C7B—C71B | 110.5 (4) |
C71A—C7A—C6A | 110.8 (4) | C72B—C7B—C6B | 109.9 (4) |
C72A—C7A—C6A | 110.9 (4) | C8B—C7B—C6B | 107.7 (4) |
C8A—C7A—C6A | 107.0 (3) | C71B—C7B—C6B | 110.2 (4) |
C7A—C71A—H71A | 109.5 | C7B—C71B—H71D | 109.5 |
C7A—C71A—H71B | 109.5 | C7B—C71B—H71E | 109.5 |
H71A—C71A—H71B | 109.5 | H71D—C71B—H71E | 109.5 |
C7A—C71A—H71C | 109.5 | C7B—C71B—H71F | 109.5 |
H71A—C71A—H71C | 109.5 | H71D—C71B—H71F | 109.5 |
H71B—C71A—H71C | 109.5 | H71E—C71B—H71F | 109.5 |
C7A—C72A—H72A | 109.5 | C7B—C72B—H72D | 109.5 |
C7A—C72A—H72B | 109.5 | C7B—C72B—H72E | 109.5 |
H72A—C72A—H72B | 109.5 | H72D—C72B—H72E | 109.5 |
C7A—C72A—H72C | 109.5 | C7B—C72B—H72F | 109.5 |
H72A—C72A—H72C | 109.5 | H72D—C72B—H72F | 109.5 |
H72B—C72A—H72C | 109.5 | H72E—C72B—H72F | 109.5 |
C9A—C8A—C7A | 113.5 (4) | C9B—C8B—C7B | 113.6 (4) |
C9A—C8A—Br8A | 108.2 (3) | C9B—C8B—Br8B | 108.3 (3) |
C7A—C8A—Br8A | 111.9 (3) | C7B—C8B—Br8B | 111.3 (3) |
C9A—C8A—H8A | 107.7 | C9B—C8B—H8B | 107.8 |
C7A—C8A—H8A | 107.7 | C7B—C8B—H8B | 107.8 |
Br8A—C8A—H8A | 107.7 | Br8B—C8B—H8B | 107.8 |
O9A—C9A—C8A | 112.3 (4) | O9B—C9B—C8B | 111.4 (4) |
O9A—C9A—C10A | 104.6 (4) | O9B—C9B—C10B | 105.4 (4) |
C8A—C9A—C10A | 109.4 (4) | C8B—C9B—C10B | 108.9 (4) |
O9A—C9A—H9C | 110.1 | O9B—C9B—H9D | 110.4 |
C8A—C9A—H9C | 110.1 | C8B—C9B—H9D | 110.4 |
C10A—C9A—H9C | 110.1 | C10B—C9B—H9D | 110.4 |
C9A—C10A—C11A | 113.2 (4) | C11B—C10B—C9B | 113.8 (4) |
C9A—C10A—H10A | 108.9 | C11B—C10B—H10C | 108.8 |
C11A—C10A—H10A | 108.9 | C9B—C10B—H10C | 108.8 |
C9A—C10A—H10B | 108.9 | C11B—C10B—H10D | 108.8 |
C11A—C10A—H10B | 108.9 | C9B—C10B—H10D | 108.8 |
H10A—C10A—H10B | 107.7 | H10C—C10B—H10D | 107.7 |
C12A—C11A—C10A | 121.4 (5) | C12B—C11B—C10B | 120.2 (4) |
C12A—C11A—C6A | 124.6 (5) | C12B—C11B—C6B | 124.2 (5) |
C10A—C11A—C6A | 114.0 (4) | C10B—C11B—C6B | 115.5 (4) |
C11A—C12A—H12A | 120.0 | C11B—C12B—H12C | 120.0 |
C11A—C12A—H12B | 120.0 | C11B—C12B—H12D | 120.0 |
H12A—C12A—H12B | 120.0 | H12C—C12B—H12D | 120.0 |
| | | |
C6A—C1A—C2A—C3A | −2.2 (8) | C6B—C1B—C2B—C3B | −4.3 (8) |
C1A—C2A—C3A—O3A | 115.8 (6) | C1B—C2B—C3B—O3B | 114.9 (5) |
C1A—C2A—C3A—C4A | −7.5 (7) | C1B—C2B—C3B—C4B | −6.5 (7) |
C1A—C2A—C3A—C31A | −130.0 (6) | C1B—C2B—C3B—C31B | −130.7 (5) |
O3A—C3A—C4A—C5A | −82.9 (5) | O3B—C3B—C4B—C5B | −82.0 (5) |
C2A—C3A—C4A—C5A | 39.2 (6) | C2B—C3B—C4B—C5B | 39.2 (6) |
C31A—C3A—C4A—C5A | 162.4 (5) | C31B—C3B—C4B—C5B | 163.1 (4) |
C3A—C4A—C5A—C6A | −64.2 (6) | C3B—C4B—C5B—C6B | −63.7 (5) |
C2A—C1A—C6A—C11A | 99.8 (6) | C2B—C1B—C6B—C11B | 100.6 (5) |
C2A—C1A—C6A—C5A | −19.7 (7) | C2B—C1B—C6B—C5B | −18.0 (6) |
C2A—C1A—C6A—C7A | −140.8 (5) | C2B—C1B—C6B—C7B | −139.2 (5) |
C4A—C5A—C6A—C1A | 51.6 (5) | C4B—C5B—C6B—C1B | 50.1 (5) |
C4A—C5A—C6A—C11A | −68.5 (5) | C4B—C5B—C6B—C11B | −70.1 (5) |
C4A—C5A—C6A—C7A | 171.5 (4) | C4B—C5B—C6B—C7B | 170.1 (4) |
C1A—C6A—C7A—C71A | 61.3 (5) | C1B—C6B—C7B—C72B | −56.5 (5) |
C11A—C6A—C7A—C71A | −177.7 (4) | C11B—C6B—C7B—C72B | 65.3 (5) |
C5A—C6A—C7A—C71A | −56.8 (5) | C5B—C6B—C7B—C72B | −174.9 (4) |
C1A—C6A—C7A—C72A | −57.9 (5) | C1B—C6B—C7B—C8B | −177.2 (4) |
C11A—C6A—C7A—C72A | 63.1 (5) | C11B—C6B—C7B—C8B | −55.3 (5) |
C5A—C6A—C7A—C72A | −176.0 (4) | C5B—C6B—C7B—C8B | 64.5 (5) |
C1A—C6A—C7A—C8A | −178.7 (4) | C1B—C6B—C7B—C71B | 62.3 (5) |
C11A—C6A—C7A—C8A | −57.7 (5) | C11B—C6B—C7B—C71B | −175.8 (4) |
C5A—C6A—C7A—C8A | 63.2 (5) | C5B—C6B—C7B—C71B | −56.0 (5) |
C71A—C7A—C8A—C9A | −178.0 (4) | C72B—C7B—C8B—C9B | −58.5 (6) |
C72A—C7A—C8A—C9A | −59.4 (6) | C71B—C7B—C8B—C9B | −178.1 (4) |
C6A—C7A—C8A—C9A | 61.5 (5) | C6B—C7B—C8B—C9B | 61.6 (5) |
C71A—C7A—C8A—Br8A | −55.2 (5) | C72B—C7B—C8B—Br8B | 64.0 (5) |
C72A—C7A—C8A—Br8A | 63.4 (5) | C71B—C7B—C8B—Br8B | −55.5 (5) |
C6A—C7A—C8A—Br8A | −175.7 (3) | C6B—C7B—C8B—Br8B | −175.9 (3) |
C7A—C8A—C9A—O9A | −173.2 (4) | C7B—C8B—C9B—O9B | −174.1 (4) |
Br8A—C8A—C9A—O9A | 61.9 (5) | Br8B—C8B—C9B—O9B | 61.7 (5) |
C7A—C8A—C9A—C10A | −57.5 (6) | C7B—C8B—C9B—C10B | −58.3 (6) |
Br8A—C8A—C9A—C10A | 177.6 (4) | Br8B—C8B—C9B—C10B | 177.5 (4) |
O9A—C9A—C10A—C11A | 171.6 (4) | O9B—C9B—C10B—C11B | 170.2 (4) |
C8A—C9A—C10A—C11A | 51.1 (6) | C8B—C9B—C10B—C11B | 50.6 (6) |
C9A—C10A—C11A—C12A | 128.1 (6) | C9B—C10B—C11B—C12B | 133.1 (5) |
C9A—C10A—C11A—C6A | −53.1 (6) | C9B—C10B—C11B—C6B | −51.0 (6) |
C1A—C6A—C11A—C12A | −5.1 (7) | C1B—C6B—C11B—C12B | −11.0 (7) |
C5A—C6A—C11A—C12A | 112.4 (6) | C5B—C6B—C11B—C12B | 106.4 (6) |
C7A—C6A—C11A—C12A | −125.5 (5) | C7B—C6B—C11B—C12B | −131.9 (5) |
C1A—C6A—C11A—C10A | 176.1 (4) | C1B—C6B—C11B—C10B | 173.2 (4) |
C5A—C6A—C11A—C10A | −66.3 (5) | C5B—C6B—C11B—C10B | −69.4 (5) |
C7A—C6A—C11A—C10A | 55.8 (5) | C7B—C6B—C11B—C10B | 52.3 (5) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O3A—H3A···O3Bi | 0.82 | 1.99 | 2.779 (6) | 160 |
O3B—H3B···O9Aii | 0.82 | 2.08 | 2.855 (5) | 158 |
O9A—H9A···O9B | 0.82 | 2.00 | 2.790 (5) | 162 |
O9B—H9B···O3Aiii | 0.82 | 2.04 | 2.765 (5) | 147 |
O9B—H9B···Br8B | 0.82 | 2.70 | 3.160 (4) | 117 |
Symmetry codes: (i) −x+1/2, −y+1, z+1/2; (ii) x+3/2, −y−1/2, −z; (iii) −x, y+3/2, −z+3/2. |
Experimental details
| (IV) | (V) |
Crystal data |
Chemical formula | C14H19BrO2 | C15H23BrO2 |
Mr | 299.20 | 315.25 |
Crystal system, space group | Orthorhombic, P212121 | Orthorhombic, P212121 |
Temperature (K) | 273 | 273 |
a, b, c (Å) | 9.9411 (16), 18.0364 (14), 7.3758 (18) | 11.872 (5), 11.897 (4), 21.575 (4) |
V (Å3) | 1322.5 (4) | 3047.2 (17) |
Z | 4 | 8 |
Radiation type | Mo Kα | Mo Kα |
µ (mm−1) | 3.10 | 2.69 |
Crystal size (mm) | 0.22 × 0.15 × 0.12 | 0.23 × 0.17 × 0.13 |
|
Data collection |
Diffractometer | Rigaku AFC-7S diffractometer | Rigaku AFC-7S diffractometer |
Absorption correction | Y scan (North et al., 1968; Molecular Structure Corporation, 1993) | ψ scan (North et al., 1968; Molecular Structure Corporation, 1993) |
Tmin, Tmax | 0.549, 0.708 | 0.577, 0.721 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2172, 2005, 1106 | 4662, 4525, 2442 |
Rint | 0.042 | 0.029 |
(sin θ/λ)max (Å−1) | 0.649 | 0.650 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.044, 0.128, 0.94 | 0.034, 0.094, 0.94 |
No. of reflections | 2005 | 4525 |
No. of parameters | 158 | 336 |
H-atom treatment | H-atom parameters constrained | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.70, −0.74 | 0.42, −0.60 |
Absolute structure | Flack (1983) | Flack (1983) |
Absolute structure parameter | −0.03 (2) | −0.011 (11) |
Hydrogen-bond geometry (Å, º) for (IV) top
D—H···A | D—H | H···A | D···A | D—H···A |
O9—H9···O3i | 0.82 | 2.11 | 2.902 (7) | 164 |
Symmetry code: (i) x+1/2, −y+1/2, −z. |
Selected torsion angles (°) for molecules (IV), (VA) and (VB) topMolecule (IV) is maílione, and molecules (VA) and (VB) are isorigidol. |
| (IV) | (VA) | (VB) |
Br8-C8-C9-O9 | -62.2 (6) | 61.9 (5) | 61.7 (5) |
C7-C8-C9-O9 | 65.6 (7) | -173.2 (4) | -174.1 (4) |
O9-C9-C10-C11 | -75.4 (8) | 171.6 (4) | 170.2 (4) |
C1-C2-C3-O3 | 176.3 (6) | 115.8 (6) | 114.9 (5) |
O3-C3-C4-C5 | -146.7 (6) | -82.9 (5) | -82.0 (5) |
Hydrogen-bond geometry (Å, º) for (V) top
D—H···A | D—H | H···A | D···A | D—H···A |
O3A—H3A···O3Bi | 0.82 | 1.99 | 2.779 (6) | 160 |
O3B—H3B···O9Aii | 0.82 | 2.08 | 2.855 (5) | 158 |
O9A—H9A···O9B | 0.82 | 2.00 | 2.790 (5) | 162 |
O9B—H9B···O3Aiii | 0.82 | 2.04 | 2.765 (5) | 147 |
Symmetry codes: (i) −x+1/2, −y+1, z+1/2; (ii) x+3/2, −y−1/2, −z; (iii) −x, y+3/2, −z+3/2. |
Chamigrenes are natural sesquiterpenes isolated from red algae of the genus Laurencia and from sea hares (opistho branch mollusks of the genus Aplysia) which feed on it. They comprise a large group of bicyclic compounds with a spiro[5.5]undecane derivative carbon skeleton. The structures of two representative chamigrenes, isoobtusol, (I), and cartilagineol, (II) (González et al., 1979; Francisco et al., 1998), as well as the structure of obtusol acetate (Perales et al., 1979), have been reported. The structures of other chamigrenes, such as rigidol, (III) (König & Wright, 1997), have been determined by spectroscopic measurement, but have not been established by X-ray diffraction. The structures of maílione, (IV), and isorigidol, (V), described in this manuscript, are compared with the proposed stereochemistry of rigidol (König & Wright, 1997).
In accord with the literature, the six-membered rings of the spironic system are labelled A and B as shown in the scheme. Ring A (C6–C11) shows the same hydrocarbon skeleton and substitution pattern (8-bromo-3-hydroxy) in compounds (I)–(V). The second ring, B (C1–C6), has different substituents and can include a double bond. The most significant difference is the presence of a methyl group substituent at C3 in (I)–(III) and (V) (sesquiterpenes). This group is replaced by a carbonyl group in maílione (nonsesquiterpene). Compound (V) crystallizes with two molecules per asymmetric unit which are labelled (VA) and (VB). Molecular dimensions in (IV) and both molecules of (V) are as expected.
The results reported here establish unequivocally the absolute configurations of (IV) and (V) and especially the stereochemistry of the 8-bromo-9-hydroxy vicinal groups. While compounds (I)–(IV) display the usual syn (or cis) configuration (typical stereochemistry observed in chamigrenes), isorigidol (V) shows an anti (or trans) arrangement. Only two other chamigrenes have been reported previously as having the hydroxy and bromine substituents in an anti configuration [(–)-10α-bromo-9β-hydroxy-α-chamigrene (König & Wright, 1997) and (1Z,8R*,9R*)-8-bromochamigra-1,11 (12)-diene-9-ol (Wright & Coll, 1990)]. In maílione, (IV), the 8-bromo group is equatorial and the 9-hydroxy group is axial (8S, 9R configuration) and in isorigidol, (V), both substituents are equatorial (8S, 9S configuration). The expected configuration for this vicinal group in rigidol, (III) (König et al., 1975) (see Scheme), is 8R, 9R. While the absolute configuration of C6 is reversed in isorigidol and maílione from that of rigidol [S in (IV) and (V), and R in (III)], C3 adopts the same R configuration in rigidol and isorigidol, as expected.
Ring A in maílione and in both independent molecules of isorigidol (VA and VB) adopts a chair conformation as can be seen in Figs. 1 and 2, and deduced from the Cremer & Pople parameters Q, θ and ϕ with values 0.568 (7) Å, 7.8 (7)° and 41 (5)° in (IV), 0.584 (5) Å, 7.5 (5)° and 61 (4)° in (VA) and 0.571 (5) Å, 8.6 (5)° and 81 (4)° in (VB) (Q = 0.6 Å and θ = 0 or 180° for the ideal cyclohexane chair). Ring B adopts an approximate half-chair puckering conformation. Q, θ and ϕ are 0.475 (7) Å, 127.0 (8)° and 48.2 (11)° in (IV), 0.511 (5) Å, 128.3 (6)° and 43.1 (7)° in (VA) and 0.511 (5) Å, 126.9 (6)° and 42.4 (7)° in (VB), while the expected θ and ϕ values for the exact half-chair conformation are 129.2 and 30°, respectively (Cremer & Pople, 1975). The conformations of both rings in the three independent molecules described here are for the most part very similar. Table 1 shows torsion angles where there are major differences between (IV) and (V). These differences arise because of the the different relative stereochemistry of the bromohydroxy vicinal groups in ring A, as well as the different hybridization at C3 (sp2 in maílione and sp3 in isorigidol).
The packing in both structures is determined by O—H···O hydrogen bonds; details are given in Tables 2 and 3. In maílione, the 9-OH group is hydrogen bonded to the oxo group (O3) of a molecule related by the twofold screw axis parallel to the b axis direction and thereby forms an infinite spiral (see Table 2). In isorigidol, the formation of a R44(8) ring between four alternate (VA) and (VB) molecules is observed (Table 3). The ring corresponds with O9A—H9A···O9B—H9B···O3Aiii—H3Aiii···O3Biv—H3Biv···O9A [symmetry codes: (iii) 0.5 + x, 1.5 - y, 1 - z; (iv) 1.5 - x, -y, 0.5 + z]. Each of the molecules participates in two of these rings, thus forming a three-dimensional network.