organic compounds
5,7-Dihydroxy-2-(3-hydroxy-4,5-dimethoxyphenyl)-6-methoxy-4H-chromen-4-one
aS. Yunusov Institute of the Chemistry of Plant Substances, Academy of Sciences of Uzbekistan, Mirzo Ulugbek Str. 77, Tashkent 100170, Uzbekistan
*Correspondence e-mail: adizovshahobiddin@yahoo.com
The title compound, C18H16O8, was isolated from the plant Artemisia baldshuanica Krasch et Zarp. The molecule is approximately planar, with the exception of the terminal methyl groups, the C atoms of which devitate from their attached ring planes by 1.243 (5) and 1.168 (5) Å. The dihedral angle between the substituted benzopyran and benzene rings is 5.8 (1)°; this near planarity could be due to conjugation or a packing effect. Intramolecular O—H⋯O and C—H⋯O hydrogen bonds occur. In the crystal, molecules are connected by O—H⋯O hydrogen bonds involving the hydroxy and carbonyl groups, forming hydrogen-bonded chains along [001] and [1-10]. The chains are linked by C—H⋯O interactions.
Related literature
For the biological activity of et al. (2011); Veitch & Grayer (2011). For related structures, see: Martinez-Vazquez et al. (1993).
see: BodewesExperimental
Crystal data
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Refinement
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Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: publCIF (Westrip, 2010).
Supporting information
10.1107/S1600536813007381/zp2001sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536813007381/zp2001Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536813007381/zp2001Isup3.cml
Air dry powdered aerial part of Artemisia baldshuanica, collected prebudding period four time extracted with ethanol. The combined extracts were concentrated under vacuum on a rotary evaporator. Concentrated extract was fractionated with benzene, chloroform, ethylacetate and ethanol. Chloroformic fraction was chromatographed on a silica gel column. Eluting the column with chloroform-ethanol (50:1) was isolated dark-yellow crystals with m.p 244-245 ° C. Crystals suitable for X-ray diffraction were obtained by slow evaporation of a solution of the compound in ethanol.
All H atoms were placed geometrically and treated as riding on their parent atoms with C–H = 0.96 Å (methyl) or 0.93 Å (aromatic) and O-H=0.82 Å with Uiso(H) = 1.5Ueq(C) (methyl), Uiso(H) = 1.2Ueq(C) (aromatic) and Uiso(H) = 1.5Ueq(O). In the absence of significant
effects Friedel pairs have been merged.Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell
CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: publCIF (Westrip, 2010).Fig. 1. Molecular structure of the title compound, displacement ellipsoids are drawn at the 50% probability level. |
C18H16O8 | F(000) = 376 |
Mr = 360.31 | Dx = 1.528 Mg m−3 |
Monoclinic, Pc | Melting point: 517(1) K |
Hall symbol: P -2yc | Cu Kα radiation, λ = 1.54184 Å |
a = 11.5837 (6) Å | Cell parameters from 1516 reflections |
b = 4.4677 (3) Å | θ = 3.9–75.1° |
c = 15.5521 (8) Å | µ = 1.04 mm−1 |
β = 103.310 (6)° | T = 300 K |
V = 783.23 (8) Å3 | Prismatic, yellow |
Z = 2 | 0.60 × 0.40 × 0.20 mm |
Oxford Diffraction Xcalibur Ruby diffractometer | 1841 independent reflections |
Radiation source: Enhance (Cu) X-ray Source | 1632 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.018 |
Detector resolution: 10.2576 pixels mm-1 | θmax = 72.0°, θmin = 3.9° |
ω scans | h = −11→14 |
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009) | k = −3→5 |
Tmin = 0.638, Tmax = 0.813 | l = −19→19 |
2540 measured reflections |
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)] = 0.042 | H-atom parameters constrained |
wR(F2) = 0.126 | w = 1/[σ2(Fo2) + (0.0802P)2 + 0.1369P] where P = (Fo2 + 2Fc2)/3 |
S = 1.07 | (Δ/σ)max = 0.001 |
1841 reflections | Δρmax = 0.16 e Å−3 |
242 parameters | Δρmin = −0.19 e Å−3 |
2 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.008 (2) |
C18H16O8 | V = 783.23 (8) Å3 |
Mr = 360.31 | Z = 2 |
Monoclinic, Pc | Cu Kα radiation |
a = 11.5837 (6) Å | µ = 1.04 mm−1 |
b = 4.4677 (3) Å | T = 300 K |
c = 15.5521 (8) Å | 0.60 × 0.40 × 0.20 mm |
β = 103.310 (6)° |
Oxford Diffraction Xcalibur Ruby diffractometer | 1841 independent reflections |
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009) | 1632 reflections with I > 2σ(I) |
Tmin = 0.638, Tmax = 0.813 | Rint = 0.018 |
2540 measured reflections |
R[F2 > 2σ(F2)] = 0.042 | 2 restraints |
wR(F2) = 0.126 | H-atom parameters constrained |
S = 1.07 | Δρmax = 0.16 e Å−3 |
1841 reflections | Δρmin = −0.19 e Å−3 |
242 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > 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 | 0.4704 (2) | 0.1567 (6) | 0.32058 (17) | 0.0446 (6) | |
O5 | 0.2167 (2) | 0.7371 (7) | 0.19407 (19) | 0.0537 (7) | |
O4 | 0.1091 (2) | 0.6830 (6) | 0.32115 (18) | 0.0499 (6) | |
H4A | 0.1203 | 0.7391 | 0.2735 | 0.075* | |
O3 | 0.1066 (2) | 0.4181 (6) | 0.48320 (16) | 0.0507 (7) | |
O2 | 0.2852 (2) | 0.0185 (7) | 0.55401 (18) | 0.0544 (7) | |
H2A | 0.2481 | 0.1197 | 0.5825 | 0.082* | |
C2 | 0.4798 (3) | 0.2888 (8) | 0.2441 (2) | 0.0391 (7) | |
C3 | 0.3979 (3) | 0.4806 (9) | 0.2006 (2) | 0.0443 (8) | |
H3A | 0.4071 | 0.5636 | 0.1478 | 0.053* | |
C4 | 0.2961 (3) | 0.5607 (8) | 0.2339 (2) | 0.0405 (7) | |
C5 | 0.1957 (3) | 0.4917 (8) | 0.3591 (2) | 0.0395 (7) | |
C6 | 0.1942 (3) | 0.3556 (8) | 0.4387 (2) | 0.0412 (7) | |
C7 | 0.2850 (3) | 0.1563 (8) | 0.4774 (2) | 0.0426 (8) | |
C8 | 0.3774 (3) | 0.0899 (9) | 0.4375 (2) | 0.0454 (8) | |
H8A | 0.4373 | −0.0424 | 0.4635 | 0.054* | |
C9 | 0.3774 (3) | 0.2264 (8) | 0.3583 (2) | 0.0385 (7) | |
C10 | 0.2897 (3) | 0.4242 (8) | 0.3162 (2) | 0.0378 (7) | |
O8 | 0.7492 (3) | 0.3071 (7) | 0.03979 (19) | 0.0587 (8) | |
O7 | 0.9075 (2) | −0.0387 (6) | 0.1554 (2) | 0.0518 (7) | |
O6 | 0.8517 (2) | −0.2462 (7) | 0.3062 (2) | 0.0561 (7) | |
H6A | 0.9159 | −0.2482 | 0.2925 | 0.084* | |
C1' | 0.5891 (3) | 0.1945 (8) | 0.2175 (2) | 0.0397 (7) | |
C2' | 0.6697 (3) | 0.0105 (8) | 0.2724 (2) | 0.0420 (8) | |
H2'A | 0.6530 | −0.0633 | 0.3241 | 0.050* | |
C3' | 0.7758 (3) | −0.0643 (8) | 0.2503 (2) | 0.0432 (8) | |
C4' | 0.8016 (3) | 0.0457 (8) | 0.1735 (2) | 0.0413 (8) | |
C5' | 0.7192 (3) | 0.2219 (9) | 0.1170 (2) | 0.0443 (8) | |
C6' | 0.6126 (3) | 0.3017 (8) | 0.1387 (2) | 0.0445 (8) | |
H6'A | 0.5582 | 0.4241 | 0.1014 | 0.053* | |
C11 | 0.0019 (4) | 0.2442 (10) | 0.4528 (3) | 0.0587 (10) | |
H11A | −0.0520 | 0.2790 | 0.4903 | 0.088* | |
H11B | 0.0225 | 0.0358 | 0.4544 | 0.088* | |
H11C | −0.0351 | 0.3008 | 0.3933 | 0.088* | |
C12 | 0.9874 (4) | 0.2038 (10) | 0.1495 (4) | 0.0619 (11) | |
H12A | 1.0519 | 0.1304 | 0.1262 | 0.093* | |
H12B | 1.0180 | 0.2864 | 0.2073 | 0.093* | |
H12C | 0.9455 | 0.3563 | 0.1112 | 0.093* | |
C13 | 0.6770 (4) | 0.5095 (10) | −0.0170 (3) | 0.0563 (10) | |
H13A | 0.7116 | 0.5524 | −0.0661 | 0.085* | |
H13B | 0.6701 | 0.6913 | 0.0143 | 0.085* | |
H13C | 0.5997 | 0.4236 | −0.0382 | 0.085* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0371 (12) | 0.0586 (14) | 0.0446 (12) | 0.0102 (11) | 0.0227 (10) | 0.0024 (11) |
O5 | 0.0449 (14) | 0.0703 (16) | 0.0533 (14) | 0.0189 (13) | 0.0266 (12) | 0.0137 (13) |
O4 | 0.0382 (12) | 0.0658 (15) | 0.0526 (14) | 0.0148 (12) | 0.0246 (11) | 0.0045 (12) |
O3 | 0.0449 (13) | 0.0656 (15) | 0.0509 (15) | 0.0012 (13) | 0.0304 (11) | −0.0103 (12) |
O2 | 0.0553 (16) | 0.0686 (17) | 0.0462 (14) | 0.0087 (14) | 0.0258 (12) | 0.0061 (12) |
C2 | 0.0319 (16) | 0.0484 (17) | 0.0413 (17) | 0.0022 (14) | 0.0170 (13) | −0.0078 (14) |
C3 | 0.0415 (17) | 0.055 (2) | 0.0429 (18) | 0.0064 (17) | 0.0233 (15) | 0.0006 (15) |
C4 | 0.0316 (15) | 0.0505 (18) | 0.0423 (18) | 0.0038 (15) | 0.0146 (14) | −0.0026 (15) |
C5 | 0.0321 (15) | 0.0503 (17) | 0.0409 (16) | 0.0003 (14) | 0.0183 (13) | −0.0065 (14) |
C6 | 0.0329 (16) | 0.0533 (17) | 0.0421 (16) | 0.0009 (14) | 0.0184 (13) | −0.0092 (15) |
C7 | 0.0464 (19) | 0.0498 (17) | 0.0359 (17) | −0.0032 (16) | 0.0181 (14) | −0.0067 (14) |
C8 | 0.0381 (17) | 0.0547 (19) | 0.0459 (18) | 0.0058 (15) | 0.0147 (14) | −0.0003 (16) |
C9 | 0.0336 (15) | 0.0479 (17) | 0.0383 (16) | 0.0012 (14) | 0.0170 (13) | −0.0071 (13) |
C10 | 0.0319 (15) | 0.0469 (16) | 0.0390 (16) | 0.0024 (13) | 0.0171 (13) | −0.0069 (13) |
O8 | 0.0532 (16) | 0.082 (2) | 0.0504 (15) | 0.0173 (15) | 0.0314 (13) | 0.0131 (14) |
O7 | 0.0425 (14) | 0.0519 (14) | 0.0716 (18) | 0.0116 (12) | 0.0354 (13) | 0.0020 (13) |
O6 | 0.0440 (14) | 0.0678 (16) | 0.0636 (16) | 0.0180 (13) | 0.0272 (12) | 0.0145 (14) |
C1' | 0.0313 (15) | 0.0485 (17) | 0.0437 (17) | −0.0019 (14) | 0.0175 (13) | −0.0074 (14) |
C2' | 0.0397 (17) | 0.0483 (17) | 0.0439 (18) | 0.0043 (15) | 0.0219 (15) | 0.0025 (14) |
C3' | 0.0368 (17) | 0.0447 (17) | 0.0509 (19) | 0.0060 (14) | 0.0155 (15) | −0.0016 (15) |
C4' | 0.0335 (16) | 0.0448 (16) | 0.0529 (19) | 0.0055 (13) | 0.0250 (15) | −0.0057 (15) |
C5' | 0.0423 (18) | 0.0553 (19) | 0.0421 (18) | 0.0015 (15) | 0.0235 (15) | −0.0037 (15) |
C6' | 0.0370 (16) | 0.0566 (19) | 0.0445 (18) | 0.0085 (16) | 0.0188 (15) | 0.0026 (15) |
C11 | 0.042 (2) | 0.076 (3) | 0.065 (2) | −0.0034 (18) | 0.0269 (18) | 0.001 (2) |
C12 | 0.0394 (19) | 0.060 (2) | 0.093 (3) | 0.0001 (17) | 0.029 (2) | 0.002 (2) |
C13 | 0.056 (2) | 0.066 (2) | 0.051 (2) | −0.0023 (19) | 0.0207 (18) | 0.0105 (18) |
O1—C2 | 1.354 (4) | O8—C13 | 1.399 (5) |
O1—C9 | 1.376 (4) | O7—C4' | 1.373 (4) |
O5—C4 | 1.260 (4) | O7—C12 | 1.441 (5) |
O4—C5 | 1.346 (4) | O6—C3' | 1.355 (5) |
O4—H4A | 0.8200 | O6—H6A | 0.8200 |
O3—C6 | 1.382 (4) | C1'—C2' | 1.382 (5) |
O3—C11 | 1.425 (5) | C1'—C6' | 1.399 (5) |
O2—C7 | 1.341 (4) | C2'—C3' | 1.391 (5) |
O2—H2A | 0.8200 | C2'—H2'A | 0.9300 |
C2—C3 | 1.340 (5) | C3'—C4' | 1.387 (5) |
C2—C1' | 1.482 (4) | C4'—C5' | 1.385 (5) |
C3—C4 | 1.438 (4) | C5'—C6' | 1.399 (5) |
C3—H3A | 0.9300 | C6'—H6'A | 0.9300 |
C4—C10 | 1.436 (5) | C11—H11A | 0.9600 |
C5—C6 | 1.383 (5) | C11—H11B | 0.9600 |
C5—C10 | 1.434 (4) | C11—H11C | 0.9600 |
C6—C7 | 1.403 (5) | C12—H12A | 0.9600 |
C7—C8 | 1.387 (5) | C12—H12B | 0.9600 |
C8—C9 | 1.374 (5) | C12—H12C | 0.9600 |
C8—H8A | 0.9300 | C13—H13A | 0.9600 |
C9—C10 | 1.391 (5) | C13—H13B | 0.9600 |
O8—C5' | 1.378 (4) | C13—H13C | 0.9600 |
C2—O1—C9 | 120.3 (3) | C2'—C1'—C2 | 119.7 (3) |
C5—O4—H4A | 109.5 | C6'—C1'—C2 | 119.9 (3) |
C6—O3—C11 | 113.0 (3) | C1'—C2'—C3' | 120.0 (3) |
C7—O2—H2A | 109.5 | C1'—C2'—H2'A | 120.0 |
C3—C2—O1 | 122.1 (3) | C3'—C2'—H2'A | 120.0 |
C3—C2—C1' | 126.3 (3) | O6—C3'—C4' | 121.9 (3) |
O1—C2—C1' | 111.6 (3) | O6—C3'—C2' | 117.7 (3) |
C2—C3—C4 | 121.4 (3) | C4'—C3'—C2' | 120.4 (3) |
C2—C3—H3A | 119.3 | O7—C4'—C5' | 123.0 (3) |
C4—C3—H3A | 119.3 | O7—C4'—C3' | 117.3 (3) |
O5—C4—C10 | 121.5 (3) | C5'—C4'—C3' | 119.6 (3) |
O5—C4—C3 | 123.1 (3) | O8—C5'—C4' | 115.8 (3) |
C10—C4—C3 | 115.5 (3) | O8—C5'—C6' | 123.6 (3) |
O4—C5—C6 | 120.7 (3) | C4'—C5'—C6' | 120.6 (3) |
O4—C5—C10 | 119.9 (3) | C5'—C6'—C1' | 119.0 (3) |
C6—C5—C10 | 119.4 (3) | C5'—C6'—H6'A | 120.5 |
O3—C6—C5 | 121.4 (3) | C1'—C6'—H6'A | 120.5 |
O3—C6—C7 | 118.6 (3) | O3—C11—H11A | 109.5 |
C5—C6—C7 | 120.0 (3) | O3—C11—H11B | 109.5 |
O2—C7—C8 | 117.1 (3) | H11A—C11—H11B | 109.5 |
O2—C7—C6 | 121.3 (3) | O3—C11—H11C | 109.5 |
C8—C7—C6 | 121.6 (3) | H11A—C11—H11C | 109.5 |
C9—C8—C7 | 117.7 (3) | H11B—C11—H11C | 109.5 |
C9—C8—H8A | 121.1 | O7—C12—H12A | 109.5 |
C7—C8—H8A | 121.1 | O7—C12—H12B | 109.5 |
C8—C9—O1 | 116.3 (3) | H12A—C12—H12B | 109.5 |
C8—C9—C10 | 123.6 (3) | O7—C12—H12C | 109.5 |
O1—C9—C10 | 120.1 (3) | H12A—C12—H12C | 109.5 |
C9—C10—C5 | 117.7 (3) | H12B—C12—H12C | 109.5 |
C9—C10—C4 | 120.5 (3) | O8—C13—H13A | 109.5 |
C5—C10—C4 | 121.7 (3) | O8—C13—H13B | 109.5 |
C5'—O8—C13 | 119.7 (3) | H13A—C13—H13B | 109.5 |
C4'—O7—C12 | 115.0 (3) | O8—C13—H13C | 109.5 |
C3'—O6—H6A | 109.5 | H13A—C13—H13C | 109.5 |
C2'—C1'—C6' | 120.4 (3) | H13B—C13—H13C | 109.5 |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2A···O3 | 0.82 | 2.38 | 2.762 (4) | 109 |
O2—H2A···O5i | 0.82 | 1.96 | 2.713 (4) | 152 |
O4—H4A···O5 | 0.82 | 1.85 | 2.579 (4) | 148 |
O6—H6A···O4ii | 0.82 | 2.20 | 2.954 (3) | 153 |
O6—H6A···O7 | 0.82 | 2.31 | 2.734 (4) | 113 |
C2′—H2′A···O1 | 0.93 | 2.32 | 2.667 (4) | 101 |
C3—H3A···O2iii | 0.93 | 2.58 | 3.246 (5) | 129 |
C12—H12B···O4iv | 0.96 | 2.55 | 3.459 (6) | 157 |
C12—H12C···O8 | 0.96 | 2.32 | 2.927 (6) | 122 |
Symmetry codes: (i) x, −y+1, z+1/2; (ii) x+1, y−1, z; (iii) x, −y+1, z−1/2; (iv) x+1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C18H16O8 |
Mr | 360.31 |
Crystal system, space group | Monoclinic, Pc |
Temperature (K) | 300 |
a, b, c (Å) | 11.5837 (6), 4.4677 (3), 15.5521 (8) |
β (°) | 103.310 (6) |
V (Å3) | 783.23 (8) |
Z | 2 |
Radiation type | Cu Kα |
µ (mm−1) | 1.04 |
Crystal size (mm) | 0.60 × 0.40 × 0.20 |
Data collection | |
Diffractometer | Oxford Diffraction Xcalibur Ruby diffractometer |
Absorption correction | Multi-scan (CrysAlis PRO; Oxford Diffraction, 2009) |
Tmin, Tmax | 0.638, 0.813 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2540, 1841, 1632 |
Rint | 0.018 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.042, 0.126, 1.07 |
No. of reflections | 1841 |
No. of parameters | 242 |
No. of restraints | 2 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.16, −0.19 |
Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick, 2008), publCIF (Westrip, 2010).
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2A···O3 | 0.82 | 2.38 | 2.762 (4) | 109.0 |
O2—H2A···O5i | 0.82 | 1.96 | 2.713 (4) | 152.0 |
O4—H4A···O5 | 0.82 | 1.85 | 2.579 (4) | 148.0 |
O6—H6A···O4ii | 0.82 | 2.20 | 2.954 (3) | 153.0 |
O6—H6A···O7 | 0.82 | 2.31 | 2.734 (4) | 113.0 |
C3—H3A···O2iii | 0.93 | 2.58 | 3.246 (5) | 129.0 |
C12—H12B···O4iv | 0.96 | 2.55 | 3.459 (6) | 157.0 |
C12—H12C···O8 | 0.96 | 2.32 | 2.927 (6) | 122.0 |
Symmetry codes: (i) x, −y+1, z+1/2; (ii) x+1, y−1, z; (iii) x, −y+1, z−1/2; (iv) x+1, y, z. |
Acknowledgements
We thank the Academy of Sciences of the Republic of Uzbekistan for supporting this study (grant No. FA-F7-T185)
References
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Among of biologically active natural compounds of plant origin flavonoids occupy an important place. Most important for practical medicine are flavonoids with antioxidant, antiinflammatory, antispasmodic and anticancer activity (Bodewes et al., 2011; Veitch et al., 2011).
Artemisia baldshuanica Krasch. et Zarp. (Asteraceae) - is a widespread in centralasia species of Artemisia and juice of leaves possesses a antihelmintic activity. The title compound, 5,7,3'-trihydroxy-6,4',5'-trimethoxyflavone (also named as 5,7,-dihydroxy-2-(3-hydroxy-4,5-dimethoxyphenyl)-6-methoxy-4H- chromen-4-one) was isolated from the ethanol extract of above-ground part of Artemisia baldshuanica.
The molecule is nearly planar with exception of H3C11- and H3C12- terminal methyl groups. Substituted benzopyran and phenyl rings are planar with r.m.s. deviations of 0.020 Å and 0.026 Å, respectivily. The angle between ring planes equals to 5.8 (1)° thanks to conjugation of π-electronic systems of cycles. Terminal methyl group carbon atoms (C11 and C12) are deviated from their ring planes to 1.243 (5) Å and 1.168 (5) Å, respectively.
The molecule has intramolecular hydrogen bond where O4-H4A···O5 hydroxylic and ketonic groups form six membered pseudocycle. (Table 1). Also it are observed O2-H2A···O3-CH3 and O6-H6A···O7-CH3 intramolecular hydrogen bonds between hydroxyl and methoxyl groups. In the crystal, molecules are interconnected via O2-H2A···O5 and O6-H6A···O4 hydrogen bonds observed between hydroxyl and carbonyl groups forming three dimensional H-bond chains. The molecules are further linked by a weak C2'-H2'A···O1, C3-H3A···O2, C12-H12B···O4 and C12-H12C···O8 intermolecular interactions (Table 1).