Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536802006074/dn6028sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536802006074/dn6028Isup2.hkl |
CCDC reference: 185777
Key indicators
- Single-crystal X-ray study
- T = 296 K
- Mean (C-C) = 0.002 Å
- R factor = 0.061
- wR factor = 0.191
- Data-to-parameter ratio = 20.5
checkCIF results
No syntax errors found ADDSYM reports no extra symmetry
The synthesis of (I) has been described by Gaillard et al. (1996), who also published 1H and 13C NMR data for the substance. Crystals suitable for X-ray analysis were obtained from benzene (m.p. 490–491 K).
H atoms were constrained to ideal geometry using an appropriate riding model. For methyl groups, the C—H distances (0.96 Å) and C–C–H angles (109.5°) were kept fixed, while the torsion angles were allowed to refine with the starting position based on the threefold averaged circular Fourier synthesis.
Data collection: SMART (Siemens, 1995); cell refinement: SAINT (Siemens, 1995); data reduction: SAINT and SADABS (Sheldrick, 2001); program(s) used to solve structure: SHELXTL (Bruker, 1997); program(s) used to refine structure: SHELXTL; molecular graphics: DIAMOND (Brandenburg, 2000); software used to prepare material for publication: SHELXTL.
C21H22O6 | F(000) = 1568 |
Mr = 370.39 | Dx = 1.339 Mg m−3 |
Monoclinic, C2/c | Melting point: 490–491 K K |
Hall symbol: -C 2yc | Mo Kα radiation, λ = 0.71073 Å |
a = 19.3584 (2) Å | Cell parameters from 5905 reflections |
b = 7.6117 (1) Å | θ = 1.6–30.5° |
c = 26.1758 (4) Å | µ = 0.10 mm−1 |
β = 107.700 (1)° | T = 296 K |
V = 3674.43 (8) Å3 | Irregular, colorless |
Z = 8 | 0.53 × 0.44 × 0.35 mm |
Siemens SMART CCD diffractometer | 5565 independent reflections |
Radiation source: fine-focus sealed tube | 4109 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.037 |
ω scans | θmax = 30.5°, θmin = 1.6° |
Absorption correction: multi-scan (SADABS; Sheldrick, 2001) | h = −27→27 |
Tmin = 0.950, Tmax = 0.967 | k = −10→10 |
23515 measured reflections | l = −37→37 |
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)] = 0.061 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.191 | H-atom parameters constrained |
S = 1.02 | w = 1/[σ2(Fo2) + (0.1046P)2 + 2.3577P] where P = (Fo2 + 2Fc2)/3 |
5565 reflections | (Δ/σ)max < 0.001 |
272 parameters | Δρmax = 0.32 e Å−3 |
0 restraints | Δρmin = −0.37 e Å−3 |
C21H22O6 | V = 3674.43 (8) Å3 |
Mr = 370.39 | Z = 8 |
Monoclinic, C2/c | Mo Kα radiation |
a = 19.3584 (2) Å | µ = 0.10 mm−1 |
b = 7.6117 (1) Å | T = 296 K |
c = 26.1758 (4) Å | 0.53 × 0.44 × 0.35 mm |
β = 107.700 (1)° |
Siemens SMART CCD diffractometer | 5565 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 2001) | 4109 reflections with I > 2σ(I) |
Tmin = 0.950, Tmax = 0.967 | Rint = 0.037 |
23515 measured reflections |
R[F2 > 2σ(F2)] = 0.061 | 0 restraints |
wR(F2) = 0.191 | H-atom parameters constrained |
S = 1.02 | Δρmax = 0.32 e Å−3 |
5565 reflections | Δρmin = −0.37 e Å−3 |
272 parameters |
Experimental. Data were collected at room temperature using a Siemens SMART CCD diffractometer. A full sphere of reciprocal space was scanned by 0.3° steps in ω with a crystal–to–detector distance of 3.97 cm, 30 s per frame. Preliminary orientation matrix was obtained from the first 100 frames using SMART (Siemens, 1995). The collected frames were integrated using the preliminary orientation matrix which was updated every 100 frames. Final cell parameters were obtained by refinement on the position of 5905 reflections with I>10σ(I) after integration of all the frames data using SAINT (Siemens, 1995). |
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. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.02601 (7) | 0.2857 (2) | −0.13252 (4) | 0.0500 (3) | |
O2 | 0.26710 (7) | 0.5218 (2) | −0.05331 (5) | 0.0489 (3) | |
O3 | 0.12825 (6) | 0.36546 (17) | 0.05651 (4) | 0.0376 (3) | |
O4 | −0.05017 (6) | 0.2213 (2) | −0.06501 (5) | 0.0505 (3) | |
O5 | 0.16114 (9) | 0.5776 (2) | 0.24443 (5) | 0.0591 (4) | |
O6 | 0.13327 (8) | 0.3019 (2) | 0.29255 (5) | 0.0541 (4) | |
C1 | 0.08198 (8) | 0.3412 (2) | −0.09004 (6) | 0.0356 (3) | |
C2 | 0.14577 (8) | 0.4071 (2) | −0.09608 (6) | 0.0370 (3) | |
H2 | 0.1511 | 0.4175 | −0.1301 | 0.047 (6)* | |
C3 | 0.20247 (8) | 0.4581 (2) | −0.05061 (6) | 0.0357 (3) | |
C4 | 0.19638 (8) | 0.4465 (2) | 0.00096 (6) | 0.0342 (3) | |
C5 | 0.13115 (8) | 0.3780 (2) | 0.00500 (5) | 0.0313 (3) | |
C6 | 0.07243 (8) | 0.3248 (2) | −0.03855 (6) | 0.0315 (3) | |
C7 | 0.03012 (11) | 0.3202 (3) | −0.18467 (7) | 0.0558 (5) | |
H7A | 0.0384 | 0.4433 | −0.1882 | 0.057 (7)* | |
H7B | −0.0146 | 0.2866 | −0.2107 | 0.093 (9)* | |
H7C | 0.0693 | 0.2541 | −0.1904 | 0.069 (7)* | |
C8 | 0.28177 (10) | 0.5211 (3) | −0.10355 (8) | 0.0532 (5) | |
H8A | 0.2777 | 0.4034 | −0.1173 | 0.055 (6)* | |
H8B | 0.3300 | 0.5640 | −0.0987 | 0.073 (7)* | |
H8C | 0.2475 | 0.5953 | −0.1285 | 0.069 (7)* | |
C9 | 0.25620 (9) | 0.5078 (3) | 0.04922 (7) | 0.0457 (4) | |
H9A | 0.3021 | 0.4713 | 0.0460 | 0.114 (12)* | |
H9B | 0.2496 | 0.4575 | 0.0810 | 0.095 (10)* | |
H9C | 0.2550 | 0.6336 | 0.0514 | 0.124 (13)* | |
C10 | 0.06792 (8) | 0.2979 (2) | 0.06699 (6) | 0.0336 (3) | |
C11 | 0.00769 (8) | 0.2495 (2) | 0.02784 (6) | 0.0337 (3) | |
C12 | 0.00543 (8) | 0.2621 (2) | −0.02897 (6) | 0.0337 (3) | |
C13 | −0.06062 (9) | 0.1872 (3) | 0.03847 (7) | 0.0430 (4) | |
H13A | −0.0619 | 0.0611 | 0.0381 | 0.103 (11)* | |
H13B | −0.1021 | 0.2318 | 0.0112 | 0.069 (7)* | |
H13C | −0.0614 | 0.2291 | 0.0729 | 0.070 (7)* | |
C14 | 0.08178 (8) | 0.2926 (2) | 0.12599 (6) | 0.0358 (3) | |
C15 | 0.11390 (9) | 0.4397 (2) | 0.15624 (6) | 0.0399 (4) | |
H15 | 0.1241 | 0.5386 | 0.1390 | 0.048 (6)* | |
C16 | 0.13061 (9) | 0.4390 (2) | 0.21174 (6) | 0.0405 (4) | |
C17 | 0.11490 (9) | 0.2895 (3) | 0.23781 (6) | 0.0400 (4) | |
C18 | 0.08389 (10) | 0.1441 (3) | 0.20786 (7) | 0.0435 (4) | |
H18 | 0.0740 | 0.0449 | 0.2251 | 0.052 (6)* | |
C19 | 0.06718 (10) | 0.1443 (3) | 0.15176 (6) | 0.0413 (4) | |
H19 | 0.0465 | 0.0457 | 0.1320 | 0.045 (5)* | |
C20 | 0.18819 (16) | 0.7187 (4) | 0.22090 (12) | 0.0722 (7) | |
H20A | 0.2214 | 0.6744 | 0.2033 | 0.095 (10)* | |
H20B | 0.2128 | 0.8006 | 0.2483 | 0.092 (10)* | |
H20C | 0.1486 | 0.7769 | 0.1952 | 0.111 (12)* | |
C21 | 0.12001 (13) | 0.1539 (4) | 0.32130 (8) | 0.0650 (6) | |
H21A | 0.0691 | 0.1274 | 0.3098 | 0.091 (9)* | |
H21B | 0.1354 | 0.1796 | 0.3590 | 0.093 (9)* | |
H21C | 0.1466 | 0.0547 | 0.3146 | 0.067 (8)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0401 (6) | 0.0810 (10) | 0.0253 (5) | −0.0161 (6) | 0.0047 (5) | −0.0017 (5) |
O2 | 0.0333 (6) | 0.0723 (9) | 0.0422 (6) | −0.0116 (6) | 0.0133 (5) | 0.0019 (6) |
O3 | 0.0320 (5) | 0.0548 (7) | 0.0251 (5) | −0.0059 (5) | 0.0075 (4) | −0.0002 (5) |
O4 | 0.0328 (6) | 0.0807 (10) | 0.0334 (6) | −0.0161 (6) | 0.0034 (5) | 0.0002 (6) |
O5 | 0.0696 (9) | 0.0648 (9) | 0.0418 (7) | −0.0186 (7) | 0.0154 (6) | −0.0145 (6) |
O6 | 0.0572 (8) | 0.0766 (10) | 0.0261 (5) | −0.0075 (7) | 0.0089 (5) | 0.0002 (6) |
C1 | 0.0317 (7) | 0.0456 (9) | 0.0270 (6) | −0.0017 (6) | 0.0049 (5) | 0.0007 (6) |
C2 | 0.0338 (7) | 0.0489 (9) | 0.0291 (7) | −0.0014 (6) | 0.0107 (6) | 0.0023 (6) |
C3 | 0.0277 (7) | 0.0441 (9) | 0.0359 (7) | −0.0018 (6) | 0.0106 (6) | 0.0023 (6) |
C4 | 0.0274 (6) | 0.0415 (8) | 0.0314 (7) | −0.0020 (6) | 0.0056 (5) | 0.0006 (6) |
C5 | 0.0299 (7) | 0.0386 (8) | 0.0251 (6) | 0.0003 (6) | 0.0076 (5) | 0.0019 (5) |
C6 | 0.0269 (6) | 0.0388 (8) | 0.0275 (6) | −0.0005 (5) | 0.0064 (5) | 0.0017 (5) |
C7 | 0.0461 (10) | 0.0919 (17) | 0.0270 (7) | −0.0098 (10) | 0.0075 (7) | −0.0009 (9) |
C8 | 0.0354 (8) | 0.0801 (15) | 0.0483 (10) | −0.0019 (9) | 0.0190 (7) | 0.0108 (10) |
C9 | 0.0346 (8) | 0.0598 (11) | 0.0370 (8) | −0.0113 (8) | 0.0023 (6) | −0.0029 (8) |
C10 | 0.0315 (7) | 0.0423 (8) | 0.0282 (6) | 0.0006 (6) | 0.0108 (5) | 0.0013 (6) |
C11 | 0.0298 (7) | 0.0415 (8) | 0.0302 (6) | 0.0002 (6) | 0.0097 (5) | 0.0014 (6) |
C12 | 0.0286 (7) | 0.0418 (8) | 0.0292 (6) | −0.0021 (6) | 0.0063 (5) | 0.0016 (6) |
C13 | 0.0322 (7) | 0.0571 (11) | 0.0419 (8) | −0.0012 (7) | 0.0143 (7) | 0.0032 (8) |
C14 | 0.0329 (7) | 0.0474 (9) | 0.0271 (6) | 0.0004 (6) | 0.0093 (5) | 0.0007 (6) |
C15 | 0.0413 (8) | 0.0473 (9) | 0.0317 (7) | −0.0018 (7) | 0.0120 (6) | 0.0009 (6) |
C16 | 0.0369 (8) | 0.0525 (10) | 0.0309 (7) | −0.0019 (7) | 0.0086 (6) | −0.0051 (7) |
C17 | 0.0336 (7) | 0.0597 (10) | 0.0260 (6) | 0.0020 (7) | 0.0079 (6) | 0.0014 (6) |
C18 | 0.0452 (9) | 0.0517 (10) | 0.0333 (7) | −0.0024 (8) | 0.0116 (7) | 0.0067 (7) |
C19 | 0.0432 (9) | 0.0488 (9) | 0.0310 (7) | −0.0047 (7) | 0.0099 (6) | −0.0003 (7) |
C20 | 0.0825 (18) | 0.0632 (14) | 0.0759 (16) | −0.0259 (13) | 0.0316 (15) | −0.0180 (13) |
C21 | 0.0622 (13) | 0.0956 (18) | 0.0356 (9) | −0.0084 (12) | 0.0123 (9) | 0.0140 (10) |
O1—C1 | 1.3623 (18) | C9—H9A | 0.9600 |
O1—C7 | 1.416 (2) | C9—H9B | 0.9600 |
O2—C3 | 1.3635 (18) | C9—H9C | 0.9600 |
O2—C8 | 1.427 (2) | C10—C11 | 1.349 (2) |
O3—C5 | 1.3697 (16) | C10—C14 | 1.486 (2) |
O3—C10 | 1.3779 (18) | C11—C12 | 1.4774 (19) |
O4—C12 | 1.2358 (18) | C11—C13 | 1.508 (2) |
O5—C16 | 1.373 (2) | C13—H13A | 0.9600 |
O5—C20 | 1.415 (3) | C13—H13B | 0.9600 |
O6—C17 | 1.3707 (18) | C13—H13C | 0.9600 |
O6—C21 | 1.421 (3) | C14—C19 | 1.388 (2) |
C1—C2 | 1.386 (2) | C14—C15 | 1.402 (2) |
C1—C6 | 1.4204 (19) | C15—C16 | 1.389 (2) |
C2—C3 | 1.406 (2) | C15—H15 | 0.9300 |
C2—H2 | 0.9300 | C16—C17 | 1.407 (3) |
C3—C4 | 1.393 (2) | C17—C18 | 1.383 (3) |
C4—C5 | 1.400 (2) | C18—C19 | 1.405 (2) |
C4—C9 | 1.505 (2) | C18—H18 | 0.9300 |
C5—C6 | 1.403 (2) | C19—H19 | 0.9300 |
C6—C12 | 1.474 (2) | C20—H20A | 0.9600 |
C7—H7A | 0.9600 | C20—H20B | 0.9600 |
C7—H7B | 0.9600 | C20—H20C | 0.9600 |
C7—H7C | 0.9600 | C21—H21A | 0.9600 |
C8—H8A | 0.9600 | C21—H21B | 0.9600 |
C8—H8B | 0.9600 | C21—H21C | 0.9600 |
C8—H8C | 0.9600 | ||
C1—O1—C7 | 117.75 (14) | O3—C10—C14 | 108.72 (12) |
C3—O2—C8 | 119.27 (14) | C10—C11—C12 | 120.08 (13) |
C5—O3—C10 | 120.85 (12) | C10—C11—C13 | 123.34 (14) |
C16—O5—C20 | 117.24 (16) | C12—C11—C13 | 116.54 (13) |
C17—O6—C21 | 117.92 (16) | O4—C12—C6 | 123.97 (13) |
O1—C1—C2 | 122.29 (13) | O4—C12—C11 | 120.29 (13) |
O1—C1—C6 | 116.53 (13) | C6—C12—C11 | 115.73 (12) |
C2—C1—C6 | 121.17 (13) | C11—C13—H13A | 109.5 |
C1—C2—C3 | 119.79 (13) | C11—C13—H13B | 109.5 |
C1—C2—H2 | 120.1 | H13A—C13—H13B | 109.5 |
C3—C2—H2 | 120.1 | C11—C13—H13C | 109.5 |
O2—C3—C4 | 114.96 (13) | H13A—C13—H13C | 109.5 |
O2—C3—C2 | 123.15 (13) | H13B—C13—H13C | 109.5 |
C4—C3—C2 | 121.89 (13) | C19—C14—C15 | 119.73 (14) |
C3—C4—C5 | 116.16 (13) | C19—C14—C10 | 121.87 (15) |
C3—C4—C9 | 121.57 (14) | C15—C14—C10 | 118.32 (14) |
C5—C4—C9 | 122.25 (14) | C16—C15—C14 | 120.67 (16) |
O3—C5—C6 | 120.95 (13) | C16—C15—H15 | 119.7 |
O3—C5—C4 | 114.09 (13) | C14—C15—H15 | 119.7 |
C6—C5—C4 | 124.95 (13) | O5—C16—C15 | 124.63 (17) |
C5—C6—C1 | 116.03 (13) | O5—C16—C17 | 115.76 (14) |
C5—C6—C12 | 119.54 (12) | C15—C16—C17 | 119.60 (16) |
C1—C6—C12 | 124.41 (13) | O6—C17—C18 | 125.26 (16) |
O1—C7—H7A | 109.5 | O6—C17—C16 | 115.20 (16) |
O1—C7—H7B | 109.5 | C18—C17—C16 | 119.54 (14) |
H7A—C7—H7B | 109.5 | C17—C18—C19 | 120.95 (16) |
O1—C7—H7C | 109.5 | C17—C18—H18 | 119.5 |
H7A—C7—H7C | 109.5 | C19—C18—H18 | 119.5 |
H7B—C7—H7C | 109.5 | C14—C19—C18 | 119.50 (16) |
O2—C8—H8A | 109.5 | C14—C19—H19 | 120.2 |
O2—C8—H8B | 109.5 | C18—C19—H19 | 120.2 |
H8A—C8—H8B | 109.5 | O5—C20—H20A | 109.5 |
O2—C8—H8C | 109.5 | O5—C20—H20B | 109.5 |
H8A—C8—H8C | 109.5 | H20A—C20—H20B | 109.5 |
H8B—C8—H8C | 109.5 | O5—C20—H20C | 109.5 |
C4—C9—H9A | 109.5 | H20A—C20—H20C | 109.5 |
C4—C9—H9B | 109.5 | H20B—C20—H20C | 109.5 |
H9A—C9—H9B | 109.5 | O6—C21—H21A | 109.5 |
C4—C9—H9C | 109.5 | O6—C21—H21B | 109.5 |
H9A—C9—H9C | 109.5 | H21A—C21—H21B | 109.5 |
H9B—C9—H9C | 109.5 | O6—C21—H21C | 109.5 |
C11—C10—O3 | 122.68 (13) | H21A—C21—H21C | 109.5 |
C11—C10—C14 | 128.59 (14) | H21B—C21—H21C | 109.5 |
C7—O1—C1—C2 | −8.9 (3) | C14—C10—C11—C13 | 3.4 (3) |
C7—O1—C1—C6 | 172.34 (17) | C5—C6—C12—O4 | 176.11 (17) |
O1—C1—C2—C3 | −178.35 (16) | C1—C6—C12—O4 | −1.9 (3) |
C6—C1—C2—C3 | 0.3 (3) | C5—C6—C12—C11 | −3.9 (2) |
C8—O2—C3—C4 | 173.28 (16) | C1—C6—C12—C11 | 178.06 (15) |
C8—O2—C3—C2 | −6.6 (3) | C10—C11—C12—O4 | −178.48 (17) |
C1—C2—C3—O2 | 179.10 (16) | C13—C11—C12—O4 | −0.6 (2) |
C1—C2—C3—C4 | −0.8 (3) | C10—C11—C12—C6 | 1.5 (2) |
O2—C3—C4—C5 | −178.68 (15) | C13—C11—C12—C6 | 179.41 (15) |
C2—C3—C4—C5 | 1.2 (2) | C11—C10—C14—C19 | 48.6 (3) |
O2—C3—C4—C9 | 2.5 (2) | O3—C10—C14—C19 | −132.30 (16) |
C2—C3—C4—C9 | −177.65 (17) | C11—C10—C14—C15 | −134.66 (19) |
C10—O3—C5—C6 | 1.0 (2) | O3—C10—C14—C15 | 44.47 (19) |
C10—O3—C5—C4 | −179.00 (14) | C19—C14—C15—C16 | −0.6 (3) |
C3—C4—C5—O3 | 178.63 (14) | C10—C14—C15—C16 | −177.49 (15) |
C9—C4—C5—O3 | −2.5 (2) | C20—O5—C16—C15 | −10.9 (3) |
C3—C4—C5—C6 | −1.3 (2) | C20—O5—C16—C17 | 170.2 (2) |
C9—C4—C5—C6 | 177.53 (16) | C14—C15—C16—O5 | −179.08 (17) |
O3—C5—C6—C1 | −179.02 (14) | C14—C15—C16—C17 | −0.2 (3) |
C4—C5—C6—C1 | 0.9 (2) | C21—O6—C17—C18 | 0.4 (3) |
O3—C5—C6—C12 | 2.8 (2) | C21—O6—C17—C16 | −178.85 (18) |
C4—C5—C6—C12 | −177.28 (15) | O5—C16—C17—O6 | −0.9 (2) |
O1—C1—C6—C5 | 178.38 (15) | C15—C16—C17—O6 | −179.86 (15) |
C2—C1—C6—C5 | −0.4 (2) | O5—C16—C17—C18 | 179.82 (16) |
O1—C1—C6—C12 | −3.5 (2) | C15—C16—C17—C18 | 0.9 (3) |
C2—C1—C6—C12 | 177.71 (16) | O6—C17—C18—C19 | −179.84 (16) |
C5—O3—C10—C11 | −3.5 (2) | C16—C17—C18—C19 | −0.6 (3) |
C5—O3—C10—C14 | 177.27 (13) | C15—C14—C19—C18 | 0.9 (3) |
O3—C10—C11—C12 | 2.1 (2) | C10—C14—C19—C18 | 177.59 (15) |
C14—C10—C11—C12 | −178.83 (15) | C17—C18—C19—C14 | −0.2 (3) |
O3—C10—C11—C13 | −175.59 (15) |
D—H···A | D—H | H···A | D···A | D—H···A |
C8—H8B···O4i | 0.96 | 2.52 | 3.454 (2) | 164 |
C9—H9B···O3 | 0.96 | 2.35 | 2.762 (2) | 106 |
Symmetry code: (i) x+1/2, y+1/2, z. |
Experimental details
Crystal data | |
Chemical formula | C21H22O6 |
Mr | 370.39 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 296 |
a, b, c (Å) | 19.3584 (2), 7.6117 (1), 26.1758 (4) |
β (°) | 107.700 (1) |
V (Å3) | 3674.43 (8) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.53 × 0.44 × 0.35 |
Data collection | |
Diffractometer | Siemens SMART CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 2001) |
Tmin, Tmax | 0.950, 0.967 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 23515, 5565, 4109 |
Rint | 0.037 |
(sin θ/λ)max (Å−1) | 0.713 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.061, 0.191, 1.02 |
No. of reflections | 5565 |
No. of parameters | 272 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.32, −0.37 |
Computer programs: SMART (Siemens, 1995), SAINT (Siemens, 1995), SAINT and SADABS (Sheldrick, 2001), SHELXTL (Bruker, 1997), SHELXTL, DIAMOND (Brandenburg, 2000).
D—H···A | D—H | H···A | D···A | D—H···A |
C8—H8B···O4i | 0.96 | 2.52 | 3.454 (2) | 164.3 |
C9—H9B···O3 | 0.96 | 2.35 | 2.762 (2) | 105.6 |
Symmetry code: (i) x+1/2, y+1/2, z. |
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Certain flavonoids are known to display cardiac effects (Laekeman et al., 1986; Cheav et al., 1989). Their presence, for instance, in regularly consumed foods may reduce the risk of death from coronary heart desease in elderly men (Hertog et al., 1993). In particular, the potential cardiovascular effects of luteolin may be attributed to the inhibition of phosphodiesterase (PDE) hydrolyzing the cyclic nucleotide cAMP (cyclic adenosine monophosphate) (Abdalla et al., 1994). In an investigation of the selective inhibition of rat heart cAMP phosphodiesterases by lipophilic C-methyl-2-phenyl-4H-1-benzopyran-4-ones (C-methylflavones), the inhibition effect of eight flavones was studied, seven of them being methyl ethers of mono- or di-C-methylluteolin (Gaillard et al., 1996). Two of the eight flavones were described for the first time. One of these was chosen for the present X-ray investigation, namely 5,7-dimethoxy-2-(3,4-dimethoxyphenyl)-3,8-dimethyl-4H-1-benzopyran-4-one, (I).
A perspective view of (I), together with the atom-numbering scheme, is shown in Fig. 1. In the benzopyran ring system, pyran ring C5/C6/C12/C11/C10/O3 forms an angle of 1.58 (6)° with the C1–C6 benzene ring plane. The pyran ring is slightly puckered (r.m.s. deviation of fitted atoms is 0.017 Å). The keto atom O4 and the methyl atom C13 are twisted out of the pyran ring plane by 0.068 (2) and 0.059 (3) Å, respectively. The C14–C19 benzene ring plane forms an angle of 47.13 (6)° with the pyran ring plane. Three of the four methoxy groups are situated significantly out of the respective benzene ring plane [torsion angles: C2—C1—O1—C7 - 8.9 (3)°, C2—C3—O2—C8 - 6.6 (3)°, C15—C16—O5—C20 - 10.9 (3)° and C18—C17—O6—C21 0.4 (3)°]. The structure is stabilized by weak C—H···O hydrogen bonds (Table 1 and Fig. 2). Apart from the intramolecular contact, the molecules form a chain [C1,1(9) in terms of graph-set theory (Bernstein et al., 1995)]. Moreover, there is a π–π interaction between parallel pyran rings (symmetry related by an inverse centre), see Fig. 3, with a perpendicular distance of 3.506 (2) Å.