The title compound, 1-hydroxy-2,3,4,7-tetramethoxy-9H-xanthen-9-one, C17H16O7, was isolated from Swertia Chirayita and is found to be planar with only two of the methoxy substituents lying out of the plane of the molecule.
Supporting information
CCDC reference: 239289
Key indicators
- Single-crystal X-ray study
- T = 293 K
- Mean (C-C) = 0.007 Å
- R factor = 0.052
- wR factor = 0.165
- Data-to-parameter ratio = 12.2
checkCIF/PLATON results
No syntax errors found
Alert level B
PLAT026_ALERT_3_B Ratio Observed / Unique Reflections too Low .... 35 Perc.
PLAT027_ALERT_3_B _diffrn_reflns_theta_full (too) Low ............ 24.98 Deg.
Alert level C
PLAT031_ALERT_4_C Refined Extinction Parameter within Range ...... 2.67 Sigma
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ... 7
0 ALERT level A = In general: serious problem
2 ALERT level B = Potentially serious problem
2 ALERT level C = Check and explain
0 ALERT level G = General alerts; check
0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
0 ALERT type 2 Indicator that the structure model may be wrong or deficient
3 ALERT type 3 Indicator that the structure quality may be low
1 ALERT type 4 Improvement, methodology, query or suggestion
Data collection: CAD-4 SDP/VAX(Enraf-Nonius, 1989); cell refinement: CAD-4 SDP/VAX; data reduction: MolEN/PC (Fair, 1990); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL7 (Sheldrick, 1997); molecular graphics: SHELXTL/PC (Siemens, 1994); software used to prepare material for publication: SHELXTL/PC.
1-hydroxy-2,3,4,7-tetramethoxy-9
H-xanthen-9-one
top
Crystal data top
C17H16O7 | F(000) = 696 |
Mr = 332.30 | Dx = 1.460 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 25 reflections |
a = 7.151 (1) Å | θ = 10–20° |
b = 13.229 (3) Å | µ = 0.12 mm−1 |
c = 16.044 (3) Å | T = 293 K |
β = 95.18 (3)° | Block, colourless |
V = 1511.6 (5) Å3 | 0.4 × 0.3 × 0.3 mm |
Z = 4 | |
Data collection top
Enraf–Nonius CAD-4 diffractometer | Rint = 0.063 |
Radiation source: fine-focus sealed tube | θmax = 25.0°, θmin = 2.0° |
Graphite monochromator | h = 0→8 |
ω/2θ scans | k = 0→15 |
2885 measured reflections | l = −19→18 |
2661 independent reflections | 3 standard reflections every 60 min |
923 reflections with I > 2σ(I) | intensity decay: 0.2% |
Refinement top
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.052 | H-atom parameters constrained |
wR(F2) = 0.165 | w = 1/[σ2(Fo2) + (0.0547P)2] where P = (Fo2 + 2Fc2)/3 |
S = 0.98 | (Δ/σ)max < 0.001 |
2661 reflections | Δρmax = 0.22 e Å−3 |
218 parameters | Δρmin = −0.28 e Å−3 |
0 restraints | Extinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0024 (9) |
Special details top
Experimental. General procedures: Melting point was performed on an XRC1 micro-melting
point apparatus and was uncorrected. NMR experiment was carried out on Varian
INOVA-400 MHz s pectrometer. Chemical shifts(Δ) were given with TMS as an
internal standard. EIMS was taken on a VG Auto Spec-3000 instrument. IR
spectra were recorded on a Nicolet-Nexus 670-FT—IR spectrometer with KBr
pellets. UV spectra were obtained on a UV-2001 spectrometer. Column
chromatography was realised on silica gel (200–300 mesh, Qingdao Marine
Chemical Inc., China). |
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 | 0.0973 (5) | 0.3180 (2) | 0.3868 (2) | 0.0671 (10) | |
O2 | 0.2618 (4) | 0.0110 (2) | 0.61283 (17) | 0.0476 (8) | |
O3 | 0.2537 (4) | −0.0606 (2) | 0.36408 (19) | 0.0591 (10) | |
O4 | 0.3341 (4) | −0.2452 (2) | 0.40539 (18) | 0.0582 (10) | |
H4A | 0.3098 | −0.1945 | 0.3737 | 0.080* | |
O5 | 0.3204 (4) | −0.1269 (3) | 0.73401 (17) | 0.0569 (9) | |
O6 | 0.4087 (5) | −0.3157 (3) | 0.69958 (19) | 0.0676 (10) | |
O7 | 0.4167 (4) | −0.3822 (2) | 0.52787 (19) | 0.0590 (10) | |
C1 | 0.0824 (7) | 0.3002 (4) | 0.2991 (3) | 0.0684 (16) | |
H1A | 0.0520 | 0.3621 | 0.2697 | 0.080* | |
H1B | 0.1998 | 0.2748 | 0.2832 | 0.080* | |
H1C | −0.0146 | 0.2513 | 0.2852 | 0.080* | |
C2 | 0.1707 (6) | 0.1404 (4) | 0.4101 (3) | 0.0485 (12) | |
H2A | 0.1629 | 0.1260 | 0.3513 | 0.080* | |
C3 | 0.1403 (6) | 0.2365 (4) | 0.4374 (3) | 0.0514 (13) | |
C4 | 0.1527 (6) | 0.2565 (4) | 0.5234 (3) | 0.0531 (13) | |
H4B | 0.1328 | 0.3242 | 0.5422 | 0.080* | |
C5 | 0.1933 (6) | 0.1814 (4) | 0.5808 (3) | 0.0491 (13) | |
H5A | 0.1998 | 0.1951 | 0.6398 | 0.080* | |
C6 | 0.2235 (6) | 0.0837 (4) | 0.5528 (3) | 0.0435 (12) | |
C7 | 0.2144 (6) | 0.0618 (4) | 0.4675 (3) | 0.0407 (11) | |
C8 | 0.2543 (6) | −0.0392 (4) | 0.4398 (3) | 0.0456 (12) | |
C9 | 0.2942 (6) | −0.1130 (3) | 0.5051 (3) | 0.0412 (11) | |
C10 | 0.3331 (6) | −0.2140 (4) | 0.4859 (3) | 0.0448 (12) | |
C11 | 0.3702 (6) | −0.2854 (4) | 0.5489 (3) | 0.0458 (12) | |
C12 | 0.3722 (6) | −0.2552 (4) | 0.6320 (3) | 0.0453 (12) | |
C13 | 0.3326 (6) | −0.1551 (4) | 0.6519 (3) | 0.0418 (12) | |
C14 | 0.2970 (6) | −0.0857 (3) | 0.5888 (3) | 0.0424 (11) | |
C15 | 0.4946 (7) | −0.0997 (4) | 0.7787 (3) | 0.0722 (17) | |
H15A | 0.4756 | −0.0803 | 0.8350 | 0.080* | |
H15B | 0.5771 | −0.1571 | 0.7798 | 0.080* | |
H15C | 0.5496 | −0.0444 | 0.7509 | 0.080* | |
C16 | 0.4285 (9) | −0.4203 (4) | 0.6965 (3) | 0.0858 (19) | |
H16A | 0.4525 | −0.4461 | 0.7524 | 0.080* | |
H16B | 0.3154 | −0.4500 | 0.6705 | 0.080* | |
H16C | 0.5317 | −0.4368 | 0.6647 | 0.080* | |
C17 | 0.2627 (7) | −0.4419 (4) | 0.4919 (3) | 0.0788 (18) | |
H17A | 0.3063 | −0.5084 | 0.4793 | 0.080* | |
H17B | 0.1702 | −0.4469 | 0.5315 | 0.080* | |
H17C | 0.2078 | −0.4106 | 0.4415 | 0.080* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
O1 | 0.080 (2) | 0.057 (2) | 0.065 (2) | 0.007 (2) | 0.0123 (19) | 0.011 (2) |
O2 | 0.052 (2) | 0.052 (2) | 0.0386 (18) | 0.0056 (17) | 0.0046 (15) | −0.0039 (17) |
O3 | 0.078 (3) | 0.058 (2) | 0.0406 (19) | 0.0020 (19) | 0.0054 (18) | 0.0011 (17) |
O4 | 0.072 (2) | 0.060 (2) | 0.042 (2) | 0.0013 (18) | 0.0019 (17) | −0.0050 (17) |
O5 | 0.061 (2) | 0.075 (2) | 0.0353 (19) | 0.0071 (19) | 0.0057 (16) | −0.0022 (17) |
O6 | 0.087 (3) | 0.061 (3) | 0.054 (2) | 0.017 (2) | 0.0031 (19) | 0.011 (2) |
O7 | 0.057 (2) | 0.056 (2) | 0.063 (2) | 0.0091 (19) | −0.0004 (18) | −0.0084 (19) |
C1 | 0.075 (4) | 0.069 (4) | 0.063 (4) | 0.014 (3) | 0.018 (3) | 0.017 (3) |
C2 | 0.047 (3) | 0.051 (3) | 0.047 (3) | −0.002 (3) | 0.007 (2) | 0.008 (3) |
C3 | 0.044 (3) | 0.049 (4) | 0.062 (4) | 0.004 (2) | 0.010 (3) | 0.013 (3) |
C4 | 0.054 (3) | 0.048 (3) | 0.058 (3) | 0.000 (3) | 0.013 (3) | 0.001 (3) |
C5 | 0.046 (3) | 0.049 (3) | 0.052 (3) | 0.000 (3) | 0.007 (2) | −0.005 (3) |
C6 | 0.036 (3) | 0.047 (3) | 0.047 (3) | −0.004 (2) | 0.002 (2) | −0.001 (3) |
C7 | 0.035 (3) | 0.050 (3) | 0.038 (3) | −0.002 (2) | 0.008 (2) | −0.001 (2) |
C8 | 0.044 (3) | 0.056 (4) | 0.037 (3) | −0.013 (3) | 0.009 (2) | −0.009 (3) |
C9 | 0.038 (3) | 0.046 (3) | 0.040 (3) | −0.004 (2) | 0.007 (2) | 0.003 (2) |
C10 | 0.035 (3) | 0.060 (4) | 0.039 (3) | 0.002 (2) | 0.000 (2) | −0.010 (3) |
C11 | 0.039 (3) | 0.040 (3) | 0.057 (3) | 0.004 (2) | −0.002 (2) | −0.003 (3) |
C12 | 0.037 (3) | 0.058 (4) | 0.040 (3) | 0.008 (2) | −0.001 (2) | 0.005 (3) |
C13 | 0.040 (3) | 0.054 (3) | 0.032 (3) | 0.006 (2) | 0.006 (2) | 0.002 (2) |
C14 | 0.034 (3) | 0.047 (3) | 0.045 (3) | 0.001 (2) | 0.001 (2) | −0.003 (3) |
C15 | 0.081 (4) | 0.074 (4) | 0.058 (3) | 0.007 (3) | −0.008 (3) | −0.009 (3) |
C16 | 0.130 (5) | 0.062 (4) | 0.063 (4) | −0.010 (4) | −0.004 (4) | 0.012 (3) |
C17 | 0.085 (4) | 0.054 (4) | 0.094 (4) | 0.011 (3) | −0.014 (4) | −0.020 (3) |
Geometric parameters (Å, º) top
O1—C3 | 1.368 (5) | C4—H4B | 0.9599 |
O1—C1 | 1.421 (5) | C5—C6 | 1.391 (6) |
O2—C14 | 1.365 (5) | C5—H5A | 0.9602 |
O2—C6 | 1.372 (5) | C6—C7 | 1.394 (5) |
O3—C8 | 1.247 (5) | C7—C8 | 1.444 (6) |
O4—C10 | 1.357 (5) | C8—C9 | 1.442 (6) |
O4—H4A | 0.8499 | C9—C14 | 1.389 (5) |
O5—C13 | 1.379 (5) | C9—C10 | 1.404 (6) |
O5—C15 | 1.426 (5) | C10—C11 | 1.391 (6) |
O6—C12 | 1.354 (5) | C11—C12 | 1.389 (6) |
O6—C16 | 1.392 (5) | C12—C13 | 1.397 (6) |
O7—C11 | 1.373 (5) | C13—C14 | 1.375 (6) |
O7—C17 | 1.434 (5) | C15—H15A | 0.9601 |
C1—H1A | 0.9598 | C15—H15B | 0.9600 |
C1—H1B | 0.9600 | C15—H15C | 0.9599 |
C1—H1C | 0.9600 | C16—H16A | 0.9600 |
C2—C3 | 1.368 (6) | C16—H16B | 0.9600 |
C2—C7 | 1.406 (6) | C16—H16C | 0.9599 |
C2—H2A | 0.9602 | C17—H17A | 0.9601 |
C3—C4 | 1.400 (6) | C17—H17B | 0.9600 |
C4—C5 | 1.368 (6) | C17—H17C | 0.9601 |
| | | |
C3—O1—C1 | 116.8 (4) | C10—C9—C8 | 121.0 (4) |
C14—O2—C6 | 119.3 (3) | O4—C10—C11 | 117.9 (4) |
C10—O4—H4A | 108.2 | O4—C10—C9 | 121.1 (4) |
C13—O5—C15 | 114.9 (3) | C11—C10—C9 | 121.0 (4) |
C12—O6—C16 | 124.9 (4) | O7—C11—C12 | 121.5 (4) |
C11—O7—C17 | 114.8 (4) | O7—C11—C10 | 119.3 (4) |
O1—C1—H1A | 109.8 | C12—C11—C10 | 119.1 (4) |
O1—C1—H1B | 109.3 | O6—C12—C11 | 125.7 (5) |
H1A—C1—H1B | 109.5 | O6—C12—C13 | 113.9 (4) |
O1—C1—H1C | 109.3 | C11—C12—C13 | 120.5 (4) |
H1A—C1—H1C | 109.5 | C14—C13—O5 | 119.9 (4) |
H1B—C1—H1C | 109.5 | C14—C13—C12 | 119.5 (4) |
C3—C2—C7 | 120.7 (5) | O5—C13—C12 | 120.5 (4) |
C3—C2—H2A | 120.2 | O2—C14—C13 | 116.4 (4) |
C7—C2—H2A | 119.1 | O2—C14—C9 | 122.0 (4) |
C2—C3—O1 | 125.2 (5) | C13—C14—C9 | 121.6 (4) |
C2—C3—C4 | 119.6 (5) | O5—C15—H15A | 110.4 |
O1—C3—C4 | 115.2 (5) | O5—C15—H15B | 108.5 |
C5—C4—C3 | 121.1 (5) | H15A—C15—H15B | 109.5 |
C5—C4—H4B | 119.7 | O5—C15—H15C | 109.5 |
C3—C4—H4B | 119.2 | H15A—C15—H15C | 109.5 |
C4—C5—C6 | 119.1 (5) | H15B—C15—H15C | 109.5 |
C4—C5—H5A | 121.0 | O6—C16—H16A | 109.3 |
C6—C5—H5A | 119.9 | O6—C16—H16B | 109.8 |
O2—C6—C5 | 116.8 (4) | H16A—C16—H16B | 109.5 |
O2—C6—C7 | 122.1 (4) | O6—C16—H16C | 109.3 |
C5—C6—C7 | 121.0 (4) | H16A—C16—H16C | 109.5 |
C6—C7—C2 | 118.5 (4) | H16B—C16—H16C | 109.5 |
C6—C7—C8 | 120.1 (4) | O7—C17—H17A | 109.7 |
C2—C7—C8 | 121.4 (4) | O7—C17—H17B | 108.7 |
O3—C8—C9 | 122.5 (4) | H17A—C17—H17B | 109.5 |
O3—C8—C7 | 121.8 (4) | O7—C17—H17C | 110.0 |
C9—C8—C7 | 115.7 (4) | H17A—C17—H17C | 109.5 |
C14—C9—C10 | 118.3 (4) | H17B—C17—H17C | 109.5 |
C14—C9—C8 | 120.7 (4) | | |
| | | |
C7—C2—C3—O1 | 179.9 (4) | C17—O7—C11—C12 | 110.1 (5) |
C7—C2—C3—C4 | 0.0 (7) | C17—O7—C11—C10 | −74.5 (5) |
C1—O1—C3—C2 | 0.4 (7) | O4—C10—C11—O7 | 3.7 (6) |
C1—O1—C3—C4 | −179.6 (4) | C9—C10—C11—O7 | −176.8 (4) |
C2—C3—C4—C5 | −0.6 (7) | O4—C10—C11—C12 | 179.2 (4) |
O1—C3—C4—C5 | 179.5 (4) | C9—C10—C11—C12 | −1.3 (7) |
C3—C4—C5—C6 | 0.3 (7) | C16—O6—C12—C11 | −8.0 (8) |
C14—O2—C6—C5 | −178.5 (4) | C16—O6—C12—C13 | 171.4 (5) |
C14—O2—C6—C7 | 1.7 (6) | O7—C11—C12—O6 | −3.6 (7) |
C4—C5—C6—O2 | −179.3 (4) | C10—C11—C12—O6 | −179.0 (4) |
C4—C5—C6—C7 | 0.5 (6) | O7—C11—C12—C13 | 177.1 (4) |
O2—C6—C7—C2 | 178.8 (4) | C10—C11—C12—C13 | 1.7 (7) |
C5—C6—C7—C2 | −1.1 (6) | C15—O5—C13—C14 | −96.4 (5) |
O2—C6—C7—C8 | −2.9 (6) | C15—O5—C13—C12 | 86.7 (5) |
C5—C6—C7—C8 | 177.3 (4) | O6—C12—C13—C14 | 178.7 (4) |
C3—C2—C7—C6 | 0.8 (6) | C11—C12—C13—C14 | −1.9 (7) |
C3—C2—C7—C8 | −177.5 (4) | O6—C12—C13—O5 | −4.4 (6) |
C6—C7—C8—O3 | −177.5 (4) | C11—C12—C13—O5 | 175.0 (4) |
C2—C7—C8—O3 | 0.8 (7) | C6—O2—C14—C13 | −179.4 (4) |
C6—C7—C8—C9 | 2.6 (6) | C6—O2—C14—C9 | −0.4 (6) |
C2—C7—C8—C9 | −179.1 (4) | O5—C13—C14—O2 | 3.9 (6) |
O3—C8—C9—C14 | 178.7 (4) | C12—C13—C14—O2 | −179.2 (4) |
C7—C8—C9—C14 | −1.3 (6) | O5—C13—C14—C9 | −175.2 (4) |
O3—C8—C9—C10 | −0.6 (7) | C12—C13—C14—C9 | 1.8 (7) |
C7—C8—C9—C10 | 179.3 (4) | C10—C9—C14—O2 | 179.6 (4) |
C14—C9—C10—O4 | −179.4 (4) | C8—C9—C14—O2 | 0.3 (6) |
C8—C9—C10—O4 | 0.0 (6) | C10—C9—C14—C13 | −1.4 (6) |
C14—C9—C10—C11 | 1.1 (6) | C8—C9—C14—C13 | 179.2 (4) |
C8—C9—C10—C11 | −179.5 (4) | | |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H4A···O3 | 0.85 | 1.82 | 2.582 (4) | 148 |
C16—H16C···O7 | 0.96 | 2.39 | 2.746 (6) | 102 |
C17—H17A···O7i | 0.96 | 2.46 | 3.302 (6) | 146 |
C17—H17C···O4 | 0.96 | 2.46 | 3.014 (6) | 117 |
Symmetry code: (i) −x+1, −y−1, −z+1. |