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Acta Crystallogr Sect E Struct Rep Online. 2010 December 1; 66(Pt 12): o3331–o3332.
Published online 2010 November 27. doi:  10.1107/S1600536810048592
PMCID: PMC3011782

12-Acetyl-6-hy­droxy-3,3,9,9-tetra­methyl­furo[3,4-b]pyrano[3,2-h]xanthene-7,11(3H,9H)-dione

Abstract

The title compound, Artonol B, C24H20O7, isolated from the stem bark of Artocarpus kemando, consists of four six-membered rings and one five-membered ring. The tricyclic xanthone ring system is almost planar [maximum deviation 0.115 (5) Å], whereas the pyran­oid ring is in a distorted boat conformation·The furan ring is almost coplanar with the fused aromatic ring, making a dihedral angle of 3.76 (9)°. The phenol ring serves as a intra­molecular hydrogen-bond donor to the adjacent carbonyl group and also acts as an inter­molecular hydrogen-bond acceptor for the methyl groups of adjacent mol­ecules, forming a three-dimensional network in the crystal.

Related literature

For bond-length data, see Allen et al. (1987 [triangle]). For related structures, see: Doriguetto et al. (2001 [triangle]); Marek et al. (2003 [triangle]); Boonnak et al. (2007 [triangle]). For the biological activity of flavonoids from Artocarpus kemando and other species of Artocarpus, see: Burkill (1935 [triangle]); Makmur et al. (1999 [triangle]); Wei et al. (2005 [triangle]); Toshio et al. (2003 [triangle]); Lin et al. (1996 [triangle]); Shimizu et al. (2000 [triangle]); Patil et al. (2002 [triangle]); Tati et al. (2001 [triangle]). For a description of the Cambridge Structural Database, see: Allen (2002 [triangle]).

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Object name is e-66-o3331-scheme1.jpg

Experimental

Crystal data

  • C24H20O7
  • M r = 420.42
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o3331-efi1.jpg
  • a = 36.511 (2) Å
  • b = 5.3275 (2) Å
  • c = 20.0218 (8) Å
  • β = 96.318 (5)°
  • V = 3870.8 (3) Å3
  • Z = 8
  • Cu Kα radiation
  • μ = 0.89 mm−1
  • T = 150 K
  • 0.30 × 0.28 × 0.04 mm

Data collection

  • Oxford Diffraction Gemini E diffractometer
  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006 [triangle]) T min = 0.780, T max = 0.965
  • 17338 measured reflections
  • 3813 independent reflections
  • 3383 reflections with I > 2.0σ(I)
  • R int = 0.018

Refinement

  • R[F 2 > 2σ(F 2)] = 0.039
  • wR(F 2) = 0.110
  • S = 0.99
  • 3813 reflections
  • 280 parameters
  • H-atom parameters constrained
  • Δρmax = 0.32 e Å−3
  • Δρmin = −0.21 e Å−3

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 [triangle]); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 2006 [triangle]); program(s) used to solve structure: SIR92 (Altomare et al., 1994 [triangle]); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003 [triangle]); molecular graphics: Mercury (Macrae et al., 2006 [triangle]); software used to prepare material for publication: CRYSTALS.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810048592/kp2279sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810048592/kp2279Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors would like to acknowledge Ministry of Science, Technology and Innovation (MOSTI) for the e-science funding provided.

supplementary crystallographic information

Comment

Flavonoids are polyphenolic compounds which are important for human health. Previous studies on flavonoids from this plant and other species of Artocarpus have revealed their wide range of pharmacological activities (Wei, et al., 2005; Toshio, et al., 2003; Lin et al., 1996; Shimizu et al., 2000; Patil et al., 2002; Tati et al., 2001). Artocarpus kemando, a tree of the forests and swamps is distributed in Thailand, Peninsular Malaysia, Sumatra and Borneo island (Burkill, 1935). In our continuing search for anti-cancer hit compounds we decided to look at Artocarpus kemando. We found that the chloroform extract of the stem bark of Artocarpus kemando displayed significant growth inhibition activities towards HL-60 cell lines and obtained Artonol B (I).

The molecular structure of (I) (Fig. 1) with the xanthone skeleton (ring B, C and D) is nearly planar with the exception of the atom C8 with the deviation from planarity of 0.115 Å. Rings A, B, C and D are individually almost planar, including the O5, O15 abd O22 atoms that are linked to them. The largest deviations from the individiual least-squares planes are 0.030 Å, 0.023 Å, 0.037 Å and 0.019 Å for ring A, B, C and D, respectively. Rings A and B form a dihedral angle of 3.06°, those of B and C ring form an angle of 4.23° and rings C and D form an dihedral angle of 3.42°. The planes of rings B and D intersect on a line which is approximately through the middle of ring C and gives rise to a dihedral angle of 7.65°. The mean torsion angle of ring D is 16.26° and it adopts a conformation half way between an envolope and a half-boat. The major pucking is in ring D at C28, owing to the constraint of the double bond between C26 and C27.

Bond distances and angles in the titled compound are in normal range (Allen et al., 1987). The average value of C—O1 bond lengths in pyranoid ring C is 1.368 Å and the observed geometries of pyranoid ring C are comparable to other reported pyranoxanthone geometries (Doriguetto et al., 2001; Marek et al.,2003; Boonnak et al., 2007). The crystal structure is stabilised by intra- and intermolecular O—H···O and C—H···O hydrogen bonding. The titled molecules exhibit a moderate intramolecular hydrogen bond O22—H221···O5, with O···O = 2.5922 (19) Å. Meanwhile, the H atom of the C31 methyl group forms a hydrogen bond with O22 at (-x, -y + 2, -z) [the C···O distance is 3.5170 (19) Å]. The H atom at C27 forms a hydrogen bond with O5 at (x, -y + 1, z - 1/2)[the C···O distance is 3.4923 (19) Å](Table 1).

The cystallographic data of this crystal structure has been deposited at Cambridge Crystallographic Data Center with deposition number CCDC 796169 (Allen, 2002).

Experimental

The powdered stem bark (4.7 kg) of Artocarpus kemando were defatted with n-hexane and sequentially extracted using methanol at room temperature for more than 48 h. This resulted in 198.5 g of methanol extract. The methanol extract was dissolved in a water-acetone mixture (1: 3, 500 mL) and the soluble portion was partitioned using chloroform (CHCl3) (3 × 400 mL) to afford a crude chloroform extract (20 g). Repeated silica gel column chromatographic separation on the chloroform extract (20 g) (hexane, hexane-chloroform, chloroform-ethyl acetate, ethyl acetate-methanol and methanol in order of increasing polarity) followed by radial chromatography yielded pure artonol B (I), fine yellow solid with melting point 462-467 K. Good single crystals for X-ray diffraction were prepared by slow evaporation and diffusion of diethyl ether into a solution of (I) in chloroform at room temperature.

Refinement

The H atoms were all located in a difference map, but those attached to carbon atoms were repositioned geometrically. The H atoms were initially refined with soft restraints on the bond lengths and angles to regularize their geometry (C—H in the range 0.93-0.98, N—H in the range 0.86–0.89 N—H to 0.86 O—H = 0.82Å) and Uiso(H) (in the range 1.2–1.5 times Ueq of the parent atom), after which the positions were refined with riding constraints.

Figures

Fig. 1.
Structure and the labeling scheme for 12-acetyl-6-hydroxy-3,3,9,9-tetramethylfuro[3,4-b]pyrano[3,2-h]xanthene-7,11(3H,9H)-dione. Displacement ellipsoids are drawn at the 50% probability level.

Crystal data

C24H20O7F(000) = 1760
Mr = 420.42Dx = 1.443 Mg m3
Monoclinic, C2/cMelting point: 189 K
Hall symbol: -C 2ycCu Kα radiation, λ = 1.54184 Å
a = 36.511 (2) ÅCell parameters from 8995 reflections
b = 5.3275 (2) Åθ = 72.0–3.5°
c = 20.0218 (8) ŵ = 0.89 mm1
β = 96.318 (5)°T = 150 K
V = 3870.8 (3) Å3Plate, yellow
Z = 80.30 × 0.28 × 0.04 mm

Data collection

Oxford Diffraction Gemini E diffractometer3813 independent reflections
Radiation source: sealed x-ray tube3383 reflections with I > 2.0σ(I)
graphiteRint = 0.018
ω/2θ scansθmax = 72.1°, θmin = 4.4°
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)h = −44→41
Tmin = 0.780, Tmax = 0.965k = −6→6
17338 measured reflectionsl = −15→24

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.039H-atom parameters constrained
wR(F2) = 0.110w = 1/[σ2(F2) + (0.07P)2 + 3.68P], where P = [max(Fo2,0) + 2Fc2]/3
S = 0.99(Δ/σ)max = 0.0003
3813 reflectionsΔρmax = 0.32 e Å3
280 parametersΔρmin = −0.21 e Å3
0 restraints

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

xyzUiso*/Ueq
O10.12808 (2)0.38440 (18)0.09348 (4)0.0198
C20.10246 (3)0.5702 (2)0.07942 (6)0.0185
C30.09197 (4)0.7295 (2)0.12975 (6)0.0191
C40.10576 (4)0.6903 (3)0.19901 (6)0.0202
O50.09659 (3)0.82336 (19)0.24578 (5)0.0261
C60.13177 (3)0.4810 (2)0.21237 (6)0.0195
C70.14301 (4)0.3455 (3)0.15819 (6)0.0190
C80.16981 (4)0.1566 (3)0.16701 (7)0.0197
C90.18272 (4)0.0989 (2)0.23308 (7)0.0201
C100.17096 (4)0.2259 (3)0.28733 (6)0.0204
C110.14611 (4)0.4195 (3)0.27803 (7)0.0205
H1110.13860.50960.31440.0256*
C120.18915 (4)0.1142 (3)0.35190 (7)0.0224
O130.21047 (3)−0.09518 (18)0.32781 (5)0.0251
C140.20880 (4)−0.1013 (3)0.25958 (7)0.0223
O150.22540 (3)−0.2519 (2)0.23027 (5)0.0287
C160.21617 (4)0.2917 (3)0.39064 (7)0.0288
H1630.20330.43530.40630.0429*
H1620.22890.20590.43010.0439*
H1610.23420.34940.36240.0428*
C170.16119 (4)0.0067 (3)0.39501 (7)0.0277
H1710.14810.13950.41450.0409*
H1720.1737−0.09250.43160.0407*
H1730.1438−0.09780.36810.0410*
C180.18478 (4)0.0411 (3)0.10628 (7)0.0213
O190.17671 (3)−0.1689 (2)0.08765 (6)0.0334
C200.20997 (4)0.2106 (3)0.07285 (7)0.0271
H2030.21850.12770.03390.0398*
H2020.23060.26080.10470.0413*
H2010.19670.36040.05750.0414*
C210.06673 (4)0.9261 (2)0.11022 (7)0.0208
O220.05637 (3)1.08580 (19)0.15665 (5)0.0275
H2210.06741.03160.19530.0432*
C230.05232 (4)0.9535 (3)0.04379 (7)0.0221
C240.06218 (4)0.7823 (2)−0.00367 (6)0.0198
C250.08781 (4)0.5891 (2)0.01261 (6)0.0194
C260.09776 (4)0.4252 (3)−0.04086 (7)0.0215
C270.07852 (4)0.4357 (3)−0.10100 (7)0.0225
C280.04539 (4)0.6033 (3)−0.11489 (6)0.0220
O290.04714 (3)0.81622 (18)−0.06783 (5)0.0252
C300.04382 (5)0.7261 (3)−0.18347 (7)0.0318
H3010.02290.8361−0.19020.0461*
H3020.06630.8214−0.18640.0468*
H3030.04180.6015−0.21760.0477*
C310.01040 (4)0.4563 (3)−0.10626 (8)0.0307
H3110.01150.3962−0.06030.0455*
H313−0.01110.5621−0.11610.0455*
H3120.00840.3170−0.13660.0447*
H2710.08450.3337−0.13660.0260*
H2610.11760.3146−0.03170.0269*
H2310.03541.08440.03130.0277*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0208 (5)0.0204 (5)0.0177 (4)0.0048 (4)−0.0006 (3)−0.0008 (3)
C20.0172 (6)0.0169 (6)0.0212 (6)0.0004 (5)0.0018 (5)0.0013 (5)
C30.0189 (6)0.0175 (6)0.0208 (6)−0.0001 (5)0.0021 (5)0.0000 (5)
C40.0210 (6)0.0188 (6)0.0209 (6)0.0001 (5)0.0029 (5)−0.0002 (5)
O50.0325 (5)0.0262 (5)0.0197 (5)0.0085 (4)0.0024 (4)−0.0030 (4)
C60.0189 (6)0.0183 (6)0.0212 (6)−0.0004 (5)0.0016 (5)0.0001 (5)
C70.0196 (6)0.0184 (6)0.0184 (6)−0.0014 (5)−0.0003 (5)0.0008 (5)
C80.0188 (6)0.0177 (6)0.0224 (6)−0.0007 (5)0.0012 (5)−0.0005 (5)
C90.0183 (6)0.0179 (6)0.0239 (6)−0.0017 (5)0.0007 (5)0.0016 (5)
C100.0197 (6)0.0202 (6)0.0208 (6)−0.0036 (5)−0.0001 (5)0.0019 (5)
C110.0223 (6)0.0197 (6)0.0194 (6)−0.0015 (5)0.0024 (5)−0.0011 (5)
C120.0235 (7)0.0204 (7)0.0225 (6)0.0008 (5)−0.0003 (5)0.0025 (5)
O130.0259 (5)0.0233 (5)0.0252 (5)0.0044 (4)−0.0011 (4)0.0042 (4)
C140.0204 (6)0.0206 (7)0.0254 (7)−0.0017 (5)−0.0008 (5)0.0028 (5)
O150.0273 (5)0.0257 (5)0.0332 (5)0.0074 (4)0.0034 (4)0.0004 (4)
C160.0289 (7)0.0285 (8)0.0274 (7)−0.0030 (6)−0.0047 (6)0.0012 (6)
C170.0302 (7)0.0287 (7)0.0242 (7)−0.0029 (6)0.0023 (6)0.0047 (6)
C180.0184 (6)0.0217 (7)0.0227 (6)0.0049 (5)−0.0027 (5)−0.0015 (5)
O190.0353 (6)0.0259 (6)0.0398 (6)−0.0016 (5)0.0080 (5)−0.0107 (5)
C200.0250 (7)0.0298 (8)0.0269 (7)0.0021 (6)0.0044 (5)−0.0014 (6)
C210.0221 (6)0.0178 (6)0.0227 (6)0.0005 (5)0.0029 (5)−0.0008 (5)
O220.0335 (5)0.0253 (5)0.0229 (5)0.0117 (4)−0.0007 (4)−0.0034 (4)
C230.0225 (6)0.0179 (6)0.0254 (7)0.0036 (5)−0.0001 (5)0.0024 (5)
C240.0210 (6)0.0189 (6)0.0189 (6)−0.0017 (5)−0.0001 (5)0.0028 (5)
C250.0191 (6)0.0187 (6)0.0203 (6)−0.0007 (5)0.0020 (5)0.0005 (5)
C260.0202 (6)0.0229 (7)0.0217 (6)0.0023 (5)0.0032 (5)0.0002 (5)
C270.0241 (7)0.0236 (7)0.0203 (6)−0.0002 (5)0.0047 (5)−0.0009 (5)
C280.0248 (7)0.0223 (7)0.0183 (6)−0.0003 (5)−0.0005 (5)0.0001 (5)
O290.0325 (5)0.0213 (5)0.0203 (5)0.0048 (4)−0.0042 (4)0.0008 (4)
C300.0414 (9)0.0323 (8)0.0207 (7)0.0030 (7)−0.0013 (6)0.0039 (6)
C310.0237 (7)0.0268 (8)0.0415 (8)0.0009 (6)0.0024 (6)0.0010 (6)

Geometric parameters (Å, °)

O1—C21.3696 (16)C17—H1730.962
O1—C71.3651 (15)C18—O191.2052 (18)
C2—C31.4025 (18)C18—C201.4982 (19)
C2—C251.3886 (18)C20—H2030.976
C3—C41.4375 (18)C20—H2020.968
C3—C211.4213 (18)C20—H2010.967
C4—O51.2490 (16)C21—O221.3449 (16)
C4—C61.4700 (18)C21—C231.3833 (19)
C6—C71.4016 (18)O22—H2210.880
C6—C111.3996 (18)C23—C241.3926 (19)
C7—C81.4009 (19)C23—H2310.947
C8—C91.3891 (18)C24—C251.4050 (19)
C8—C181.5175 (18)C24—O291.3524 (15)
C9—C101.3875 (19)C25—C261.4582 (18)
C9—C141.4879 (18)C26—C271.3269 (19)
C10—C111.3727 (19)C26—H2610.937
C10—C121.5093 (18)C27—C281.5048 (19)
C11—H1110.938C27—H2710.941
C12—O131.4715 (17)C28—O291.4714 (16)
C12—C161.5166 (19)C28—C301.5162 (18)
C12—C171.5196 (19)C28—C311.524 (2)
O13—C141.3610 (17)C30—H3010.960
C14—O151.1973 (17)C30—H3020.972
C16—H1630.969C30—H3030.950
C16—H1620.984C31—H3110.972
C16—H1610.962C31—H3130.970
C17—H1710.961C31—H3120.957
C17—H1720.975
C2—O1—C7119.81 (10)H172—C17—H173109.4
O1—C2—C3121.60 (11)C8—C18—O19121.81 (13)
O1—C2—C25115.63 (11)C8—C18—C20113.98 (11)
C3—C2—C25122.77 (12)O19—C18—C20124.21 (13)
C2—C3—C4120.74 (12)C18—C20—H203110.5
C2—C3—C21117.93 (12)C18—C20—H202110.0
C4—C3—C21121.32 (12)H203—C20—H202111.0
C3—C4—O5123.14 (12)C18—C20—H201109.1
C3—C4—C6115.85 (11)H203—C20—H201108.3
O5—C4—C6121.01 (12)H202—C20—H201107.9
C4—C6—C7119.24 (12)C3—C21—O22119.96 (12)
C4—C6—C11121.07 (12)C3—C21—C23120.59 (12)
C7—C6—C11119.68 (12)O22—C21—C23119.44 (12)
C6—C7—O1122.41 (12)C21—O22—H221105.3
C6—C7—C8122.17 (12)C21—C23—C24119.16 (12)
O1—C7—C8115.41 (11)C21—C23—H231120.0
C7—C8—C9116.00 (12)C24—C23—H231120.8
C7—C8—C18119.90 (11)C23—C24—C25122.48 (12)
C9—C8—C18123.96 (12)C23—C24—O29116.88 (12)
C8—C9—C10122.38 (12)C25—C24—O29120.57 (12)
C8—C9—C14129.44 (12)C24—C25—C2116.94 (12)
C10—C9—C14108.15 (12)C24—C25—C26118.80 (12)
C9—C10—C11121.15 (12)C2—C25—C26124.25 (12)
C9—C10—C12109.47 (12)C25—C26—C27119.42 (12)
C11—C10—C12129.38 (12)C25—C26—H261118.9
C6—C11—C10118.48 (12)C27—C26—H261121.7
C6—C11—H111120.0C26—C27—C28121.82 (12)
C10—C11—H111121.6C26—C27—H271121.3
C10—C12—O13102.52 (10)C28—C27—H271116.8
C10—C12—C16113.10 (12)C27—C28—O29111.21 (11)
O13—C12—C16107.61 (11)C27—C28—C30111.89 (12)
C10—C12—C17112.04 (11)O29—C28—C30104.02 (11)
O13—C12—C17108.25 (11)C27—C28—C31109.92 (12)
C16—C12—C17112.61 (12)O29—C28—C31107.55 (11)
C12—O13—C14112.35 (10)C30—C28—C31112.06 (12)
C9—C14—O13107.28 (11)C28—O29—C24119.33 (10)
C9—C14—O15130.08 (13)C28—C30—H301110.0
O13—C14—O15122.60 (12)C28—C30—H302109.4
C12—C16—H163110.2H301—C30—H302109.6
C12—C16—H162110.1C28—C30—H303110.0
H163—C16—H162108.0H301—C30—H303109.1
C12—C16—H161110.3H302—C30—H303108.8
H163—C16—H161109.0C28—C31—H311109.2
H162—C16—H161109.1C28—C31—H313110.4
C12—C17—H171110.4H311—C31—H313109.4
C12—C17—H172110.0C28—C31—H312109.4
H171—C17—H172107.9H311—C31—H312109.8
C12—C17—H173110.0H313—C31—H312108.6
H171—C17—H173109.1

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C16—H161···O15i0.962.553.4062 (19)148
C20—H202···O13i0.972.533.4918 (19)171
O22—H221···O50.881.782.5922 (19)153
C31—H313···O22ii0.972.573.5170 (19)165
C27—H271···O5iii0.942.583.4923 (19)163

Symmetry codes: (i) −x+1/2, y+1/2, −z+1/2; (ii) −x, −y+2, −z; (iii) x, −y+1, z−1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: KP2279).

References

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