organic compounds
3,9-Dimethyl-2,3-dihydrophenanthro[1,2-b]furan-4,5-dione
aCollege of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022, People's Republic of China, and bLuoyang Zisheng Science & Technology Co Ltd, Luoyang 471000, People's Republic of China
*Correspondence e-mail: yjc@lynu.edu.cn
The title compound, C18H14O3, consists of a four-ring system which contains three six-membered rings forming a phenanthrenedione system and a five-membered 1,2-dihydromethylfuran ring. A three-dimensional supramolecular framework is formed via non-classical intermolecular C—H⋯O hydrogen bonds.
Related literature
For tanshinone compounds, see: Chang et al. (1991); Ryu et al. (1997); Xue et al. (1999); Yagi et al. (1989); Zhang et al. (2005); Zhu & Luo (2004).
Experimental
Crystal data
|
Refinement
|
Data collection: SMART (Bruker, 2004); cell SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.
Supporting information
10.1107/S1600536809047667/rk2163sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809047667/rk2163Isup2.hkl
All reagents were of AR grade and were used without further purification. Dried powder of Salvia miltiorrhiza Bunge was exacted with EtOH and the extract was concentrated in vacuo. The residue was subjected to silica gel coloumn
Elution with petroleum ether–ethyl acetate (9:1 v/v) yielded the title compound. Elemental analysis - found: C, 77.68 %; H, 5.07 %; calc. for C18H14O3: C, 77.14 %; H, 5.05 %.All H atoms attached to C atoms were treated as riding, with C—H = 0.9300Å for aromatic H, C—H = 0.9700Å for methylene group, C—H = 0.9800Å for methyne group and C—H = 0.9600Å for methyl group with Uiso(H) = 1.2Ueq(C) of the carrier atoms to which they are attached and Uiso(H) = 1.5Ueq(C) for the methyl groups. 1004 Friedel pairs were merged.
Data collection: SMART (Bruker, 2004); cell
SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).C18H14O3 | F(000) = 584 |
Mr = 278.29 | Dx = 1.381 Mg m−3 |
Orthorhombic, P212121 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2ac 2ab | Cell parameters from 634 reflections |
a = 4.6415 (10) Å | θ = 2.5–18.2° |
b = 14.692 (3) Å | µ = 0.09 mm−1 |
c = 19.633 (4) Å | T = 295 K |
V = 1338.8 (5) Å3 | Block, yellow |
Z = 4 | 0.25 × 0.10 × 0.05 mm |
Bruker SMART APEX diffractometer | 2502 independent reflections |
Radiation source: fine-focus sealed tube | 1140 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.079 |
ϕ and ω scans | θmax = 25.5°, θmin = 2.8° |
Absorption correction: multi-scan (SADABS; Bruker, 2004) | h = −5→5 |
Tmin = 0.977, Tmax = 0.995 | k = −16→17 |
6925 measured reflections | l = −23→21 |
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)] = 0.052 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.077 | H-atom parameters constrained |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0115P)2] where P = (Fo2 + 2Fc2)/3 |
2502 reflections | (Δ/σ)max < 0.001 |
192 parameters | Δρmax = 0.38 e Å−3 |
0 restraints | Δρmin = −0.26 e Å−3 |
C18H14O3 | V = 1338.8 (5) Å3 |
Mr = 278.29 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 4.6415 (10) Å | µ = 0.09 mm−1 |
b = 14.692 (3) Å | T = 295 K |
c = 19.633 (4) Å | 0.25 × 0.10 × 0.05 mm |
Bruker SMART APEX diffractometer | 2502 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2004) | 1140 reflections with I > 2σ(I) |
Tmin = 0.977, Tmax = 0.995 | Rint = 0.079 |
6925 measured reflections |
R[F2 > 2σ(F2)] = 0.052 | 0 restraints |
wR(F2) = 0.077 | H-atom parameters constrained |
S = 1.03 | Δρmax = 0.38 e Å−3 |
2502 reflections | Δρmin = −0.26 e Å−3 |
192 parameters |
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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 | 0.9141 (6) | 0.38978 (16) | 0.80968 (12) | 0.0805 (9) | |
O2 | 0.5033 (6) | 0.47076 (16) | 0.73687 (12) | 0.0795 (9) | |
O3 | 0.5747 (6) | 0.72625 (16) | 0.87005 (12) | 0.0692 (8) | |
C1 | 1.4263 (9) | 0.4722 (3) | 1.04455 (18) | 0.0556 (10) | |
C2 | 1.5314 (9) | 0.3891 (3) | 1.03047 (19) | 0.0667 (12) | |
H2 | 1.6605 | 0.3621 | 1.0605 | 0.080* | |
C3 | 1.4497 (9) | 0.3423 (2) | 0.9711 (2) | 0.0657 (12) | |
H3 | 1.5261 | 0.2849 | 0.9628 | 0.079* | |
C4 | 1.2618 (8) | 0.3789 (2) | 0.92557 (19) | 0.0569 (11) | |
H4 | 1.2110 | 0.3464 | 0.8867 | 0.068* | |
C5 | 1.1438 (8) | 0.4660 (2) | 0.93705 (17) | 0.0448 (10) | |
C6 | 1.2314 (8) | 0.5139 (3) | 0.99724 (17) | 0.0467 (10) | |
C7 | 1.1235 (9) | 0.6017 (3) | 1.00860 (17) | 0.0574 (11) | |
H7 | 1.1801 | 0.6331 | 1.0475 | 0.069* | |
C8 | 0.9366 (9) | 0.6424 (2) | 0.96396 (18) | 0.0597 (12) | |
H8 | 0.8690 | 0.7009 | 0.9724 | 0.072* | |
C9 | 0.8490 (8) | 0.5959 (2) | 0.90615 (18) | 0.0485 (10) | |
C10 | 0.9455 (8) | 0.5084 (2) | 0.89194 (16) | 0.0441 (9) | |
C11 | 0.8348 (8) | 0.4632 (3) | 0.82957 (18) | 0.0508 (10) | |
C12 | 0.6103 (9) | 0.5125 (2) | 0.78450 (18) | 0.0547 (11) | |
C13 | 0.5429 (8) | 0.6037 (2) | 0.80144 (18) | 0.0482 (10) | |
C14 | 0.6529 (8) | 0.6393 (2) | 0.8583 (2) | 0.0514 (11) | |
C15 | 0.3586 (8) | 0.6724 (2) | 0.76485 (18) | 0.0610 (11) | |
H15 | 0.1590 | 0.6507 | 0.7634 | 0.073* | |
C16 | 0.3806 (9) | 0.7536 (3) | 0.81363 (19) | 0.0889 (14) | |
H16A | 0.4581 | 0.8062 | 0.7901 | 0.107* | |
H16B | 0.1917 | 0.7692 | 0.8313 | 0.107* | |
C17 | 1.5136 (8) | 0.5226 (3) | 1.10832 (15) | 0.0772 (13) | |
H17A | 1.3472 | 0.5322 | 1.1365 | 0.116* | |
H17B | 1.5959 | 0.5803 | 1.0962 | 0.116* | |
H17C | 1.6532 | 0.4873 | 1.1329 | 0.116* | |
C18 | 0.4609 (9) | 0.6927 (2) | 0.69344 (17) | 0.0875 (15) | |
H18A | 0.6569 | 0.7135 | 0.6949 | 0.131* | |
H18B | 0.3414 | 0.7391 | 0.6737 | 0.131* | |
H18C | 0.4494 | 0.6385 | 0.6663 | 0.131* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.106 (2) | 0.0545 (17) | 0.0810 (19) | 0.0212 (18) | −0.0224 (18) | −0.0241 (15) |
O2 | 0.096 (2) | 0.0665 (18) | 0.0754 (19) | −0.0015 (18) | −0.0249 (18) | −0.0080 (16) |
O3 | 0.089 (2) | 0.0457 (16) | 0.0727 (18) | 0.0135 (17) | −0.0073 (16) | −0.0040 (14) |
C1 | 0.053 (3) | 0.065 (3) | 0.049 (3) | −0.011 (3) | 0.000 (2) | −0.001 (2) |
C2 | 0.064 (3) | 0.074 (3) | 0.062 (3) | 0.004 (3) | −0.005 (2) | 0.007 (3) |
C3 | 0.070 (3) | 0.053 (3) | 0.073 (3) | 0.010 (3) | −0.002 (3) | −0.002 (2) |
C4 | 0.063 (3) | 0.047 (3) | 0.061 (3) | 0.005 (2) | −0.001 (2) | −0.003 (2) |
C5 | 0.044 (2) | 0.044 (2) | 0.047 (2) | −0.008 (2) | 0.009 (2) | 0.001 (2) |
C6 | 0.047 (2) | 0.047 (3) | 0.045 (2) | −0.008 (2) | 0.009 (2) | −0.001 (2) |
C7 | 0.068 (3) | 0.053 (3) | 0.052 (3) | −0.009 (3) | 0.004 (2) | −0.015 (2) |
C8 | 0.075 (3) | 0.045 (2) | 0.059 (3) | 0.000 (2) | 0.000 (3) | −0.012 (2) |
C9 | 0.054 (3) | 0.040 (2) | 0.052 (3) | −0.003 (2) | 0.006 (2) | 0.001 (2) |
C10 | 0.049 (2) | 0.042 (2) | 0.041 (2) | −0.005 (2) | 0.009 (2) | −0.004 (2) |
C11 | 0.052 (3) | 0.044 (2) | 0.056 (3) | 0.002 (2) | 0.004 (2) | 0.000 (2) |
C12 | 0.060 (3) | 0.050 (3) | 0.054 (3) | −0.009 (2) | 0.000 (2) | 0.000 (2) |
C13 | 0.055 (3) | 0.041 (2) | 0.049 (2) | −0.005 (2) | 0.007 (2) | 0.005 (2) |
C14 | 0.060 (3) | 0.032 (2) | 0.063 (3) | 0.002 (2) | 0.016 (2) | 0.000 (2) |
C15 | 0.058 (3) | 0.058 (3) | 0.067 (3) | 0.003 (2) | 0.001 (2) | 0.007 (2) |
C16 | 0.111 (4) | 0.065 (3) | 0.091 (3) | 0.029 (3) | −0.024 (3) | 0.004 (3) |
C17 | 0.078 (3) | 0.099 (3) | 0.055 (2) | −0.002 (3) | −0.010 (2) | −0.008 (2) |
C18 | 0.113 (4) | 0.078 (3) | 0.071 (3) | 0.024 (3) | 0.020 (3) | 0.023 (2) |
O1—C11 | 1.205 (4) | C8—H8 | 0.9300 |
O2—C12 | 1.223 (3) | C9—C10 | 1.390 (4) |
O3—C14 | 1.347 (3) | C9—C14 | 1.455 (5) |
O3—C16 | 1.483 (4) | C10—C11 | 1.485 (4) |
C1—C2 | 1.344 (4) | C11—C12 | 1.547 (5) |
C1—C6 | 1.434 (4) | C12—C13 | 1.416 (4) |
C1—C17 | 1.510 (4) | C13—C14 | 1.335 (4) |
C2—C3 | 1.405 (4) | C13—C15 | 1.505 (4) |
C2—H2 | 0.9300 | C15—C18 | 1.510 (4) |
C3—C4 | 1.360 (4) | C15—C16 | 1.533 (4) |
C3—H3 | 0.9300 | C15—H15 | 0.9800 |
C4—C5 | 1.410 (4) | C16—H16A | 0.9700 |
C4—H4 | 0.9300 | C16—H16B | 0.9700 |
C5—C10 | 1.421 (4) | C17—H17A | 0.9600 |
C5—C6 | 1.435 (4) | C17—H17B | 0.9600 |
C6—C7 | 1.401 (4) | C17—H17C | 0.9600 |
C7—C8 | 1.371 (4) | C18—H18A | 0.9600 |
C7—H7 | 0.9300 | C18—H18B | 0.9600 |
C8—C9 | 1.386 (4) | C18—H18C | 0.9600 |
C14—O3—C16 | 107.0 (3) | O2—C12—C13 | 124.4 (4) |
C2—C1—C6 | 118.9 (4) | O2—C12—C11 | 118.4 (3) |
C2—C1—C17 | 121.2 (4) | C13—C12—C11 | 117.2 (4) |
C6—C1—C17 | 119.8 (3) | C14—C13—C12 | 118.9 (4) |
C1—C2—C3 | 121.2 (4) | C14—C13—C15 | 110.7 (3) |
C1—C2—H2 | 119.4 | C12—C13—C15 | 130.4 (4) |
C3—C2—H2 | 119.4 | C13—C14—O3 | 114.3 (4) |
C4—C3—C2 | 121.7 (4) | C13—C14—C9 | 127.4 (4) |
C4—C3—H3 | 119.2 | O3—C14—C9 | 118.3 (4) |
C2—C3—H3 | 119.2 | C13—C15—C18 | 113.4 (3) |
C3—C4—C5 | 120.2 (4) | C13—C15—C16 | 100.7 (3) |
C3—C4—H4 | 119.9 | C18—C15—C16 | 113.9 (3) |
C5—C4—H4 | 119.9 | C13—C15—H15 | 109.5 |
C4—C5—C10 | 123.4 (4) | C18—C15—H15 | 109.5 |
C4—C5—C6 | 117.9 (3) | C16—C15—H15 | 109.5 |
C10—C5—C6 | 118.8 (3) | O3—C16—C15 | 107.2 (3) |
C7—C6—C1 | 121.0 (4) | O3—C16—H16A | 110.3 |
C7—C6—C5 | 118.8 (3) | C15—C16—H16A | 110.3 |
C1—C6—C5 | 120.2 (3) | O3—C16—H16B | 110.3 |
C8—C7—C6 | 121.8 (4) | C15—C16—H16B | 110.3 |
C8—C7—H7 | 119.1 | H16A—C16—H16B | 108.5 |
C6—C7—H7 | 119.1 | C1—C17—H17A | 109.5 |
C7—C8—C9 | 119.6 (4) | C1—C17—H17B | 109.5 |
C7—C8—H8 | 120.2 | H17A—C17—H17B | 109.5 |
C9—C8—H8 | 120.2 | C1—C17—H17C | 109.5 |
C8—C9—C10 | 121.7 (4) | H17A—C17—H17C | 109.5 |
C8—C9—C14 | 119.7 (4) | H17B—C17—H17C | 109.5 |
C10—C9—C14 | 118.5 (4) | C15—C18—H18A | 109.5 |
C9—C10—C5 | 119.3 (3) | C15—C18—H18B | 109.5 |
C9—C10—C11 | 117.9 (4) | H18A—C18—H18B | 109.5 |
C5—C10—C11 | 122.8 (3) | C15—C18—H18C | 109.5 |
O1—C11—C10 | 124.2 (4) | H18A—C18—H18C | 109.5 |
O1—C11—C12 | 116.1 (3) | H18B—C18—H18C | 109.5 |
C10—C11—C12 | 119.7 (3) | ||
C6—C1—C2—C3 | −1.1 (6) | C5—C10—C11—O1 | −4.4 (6) |
C17—C1—C2—C3 | 179.9 (3) | C9—C10—C11—C12 | −2.3 (5) |
C1—C2—C3—C4 | 0.0 (6) | C5—C10—C11—C12 | 177.7 (3) |
C2—C3—C4—C5 | 0.2 (6) | O1—C11—C12—O2 | 8.4 (5) |
C3—C4—C5—C10 | −179.7 (3) | C10—C11—C12—O2 | −173.6 (3) |
C3—C4—C5—C6 | 0.7 (5) | O1—C11—C12—C13 | −171.5 (4) |
C2—C1—C6—C7 | −177.9 (4) | C10—C11—C12—C13 | 6.5 (5) |
C17—C1—C6—C7 | 1.1 (5) | O2—C12—C13—C14 | 173.8 (4) |
C2—C1—C6—C5 | 2.0 (5) | C11—C12—C13—C14 | −6.4 (5) |
C17—C1—C6—C5 | −179.0 (3) | O2—C12—C13—C15 | −6.3 (6) |
C4—C5—C6—C7 | 178.1 (3) | C11—C12—C13—C15 | 173.6 (3) |
C10—C5—C6—C7 | −1.5 (4) | C12—C13—C14—O3 | −179.6 (3) |
C4—C5—C6—C1 | −1.8 (5) | C15—C13—C14—O3 | 0.4 (4) |
C10—C5—C6—C1 | 178.6 (3) | C12—C13—C14—C9 | 2.3 (6) |
C1—C6—C7—C8 | −179.9 (3) | C15—C13—C14—C9 | −177.7 (3) |
C5—C6—C7—C8 | 0.2 (5) | C16—O3—C14—C13 | 0.8 (4) |
C6—C7—C8—C9 | 0.5 (6) | C16—O3—C14—C9 | 179.1 (3) |
C7—C8—C9—C10 | 0.1 (5) | C8—C9—C14—C13 | −178.3 (4) |
C7—C8—C9—C14 | −179.4 (3) | C10—C9—C14—C13 | 2.2 (6) |
C8—C9—C10—C5 | −1.3 (5) | C8—C9—C14—O3 | 3.7 (5) |
C14—C9—C10—C5 | 178.1 (3) | C10—C9—C14—O3 | −175.8 (3) |
C8—C9—C10—C11 | 178.7 (3) | C14—C13—C15—C18 | 120.7 (3) |
C14—C9—C10—C11 | −1.9 (5) | C12—C13—C15—C18 | −59.3 (5) |
C4—C5—C10—C9 | −177.5 (3) | C14—C13—C15—C16 | −1.4 (4) |
C6—C5—C10—C9 | 2.0 (4) | C12—C13—C15—C16 | 178.7 (4) |
C4—C5—C10—C11 | 2.5 (5) | C14—O3—C16—C15 | −1.7 (4) |
C6—C5—C10—C11 | −178.0 (3) | C13—C15—C16—O3 | 1.8 (4) |
C9—C10—C11—O1 | 175.6 (4) | C18—C15—C16—O3 | −120.0 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
C18—H18B···O1i | 0.96 | 2.53 | 3.379 (4) | 147 |
C16—H16A···O2i | 0.97 | 2.48 | 3.384 (5) | 155 |
C17—H17A···O2ii | 0.96 | 2.56 | 3.484 (4) | 162 |
C17—H17C···O2iii | 0.96 | 2.66 | 3.377 (4) | 132 |
C7—H7···O3iv | 0.93 | 2.67 | 3.481 (4) | 146 |
Symmetry codes: (i) −x+1, y+1/2, −z+3/2; (ii) −x+3/2, −y+1, z+1/2; (iii) −x+5/2, −y+1, z+1/2; (iv) x+1/2, −y+3/2, −z+2. |
Experimental details
Crystal data | |
Chemical formula | C18H14O3 |
Mr | 278.29 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 295 |
a, b, c (Å) | 4.6415 (10), 14.692 (3), 19.633 (4) |
V (Å3) | 1338.8 (5) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.25 × 0.10 × 0.05 |
Data collection | |
Diffractometer | Bruker SMART APEX diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2004) |
Tmin, Tmax | 0.977, 0.995 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6925, 2502, 1140 |
Rint | 0.079 |
(sin θ/λ)max (Å−1) | 0.606 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.052, 0.077, 1.03 |
No. of reflections | 2502 |
No. of parameters | 192 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.38, −0.26 |
Computer programs: SMART (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
C18—H18B···O1i | 0.96 | 2.53 | 3.379 (4) | 147.1 |
C16—H16A···O2i | 0.97 | 2.48 | 3.384 (5) | 154.8 |
C17—H17A···O2ii | 0.96 | 2.56 | 3.484 (4) | 162.4 |
C17—H17C···O2iii | 0.96 | 2.66 | 3.377 (4) | 131.6 |
C7—H7···O3iv | 0.93 | 2.67 | 3.481 (4) | 146.1 |
Symmetry codes: (i) −x+1, y+1/2, −z+3/2; (ii) −x+3/2, −y+1, z+1/2; (iii) −x+5/2, −y+1, z+1/2; (iv) x+1/2, −y+3/2, −z+2. |
Acknowledgements
This work was supported by the Natural Science Foundation of Henan Province (No. 092102310075) and the Education Chamber of Henan Province (No. 2008B150013 ), which are gratefully acknowledged.
References
Bruker (2004). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Chang, H.-M., Chui, K.-Y., Tan, F. W. L., Yang, Y., Zhong, Z.-P., Lee, C.-M., Sham, H.-L. & Wong, H. N. C. (1991). J. Med. Chem. 34, 1675–1692. CrossRef PubMed CAS Web of Science Google Scholar
Ryu, S. Y., Lee, C. O. & Choi, S. U. (1997). Planta Med. 63, 339–342. CrossRef CAS PubMed Web of Science Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Xue, M., Cui, Y., Wang, H.-Q., Hu, H.-Y. & Zhang, B.-J. (1999). Pharm. Biomed. Anal. 21, 207–213. Web of Science CrossRef Google Scholar
Yagi, A., Fujimoto, K., Tanonaka, K., Hirai, K. & Takeo, S. (1989). Planta Med. B55, 51–54. CrossRef Google Scholar
Zhang, L., Wang, J.-K., Qu, Y. & Nie, Q. (2005). Acta Cryst. E61, o3582–o3583. Web of Science CSD CrossRef IUCr Journals Google Scholar
Zhu, J.-R. & Luo, H.-W. (2004). J. Chin. Pharm. Univ. 35, 368–370. CAS Google Scholar
This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
The Chinese herbal medicine, Danshen, is the dried rhizome of Salviae Miltiorrhiza Bunge and Salvia Przewalskii Maxim (Labiatae). It contains two parts of efective components (liposoluble tanshinones and aqueous-soluble salvianolic acids). Up to date, 41 tanshinones and 18 salvianolic acids have been extracted and reported. Tanshinones have been widely used in China to treat coronary heart diseases (Chang et al., 1991), antibacterial (Zhu et al., 2004), antitumour (Ryu et al., 1997), angina pectoris and myocardial infarction (Xue et al., 1999), cerebrovascular and neurasthenic insomnia problems (Yagi et al., 1989).
The title compound, C18H14O3, (I) consists of a four-ring system in which contains three six-membered rings forming a phenanthrene-dione system, and a five-membered 1,2-dihydro-methylfuran ring (Fig. 1). The whole molecule is essentially planar, with a torsion angle C15—C13—C14—O3 = 0.40 (4)° in the furan ring, the torsion angles C1—C2—C3—C4 = 0.01 (6)° and C4—C5—C6—C1 = -1.80 (5)° from the terminal six-membered ring. In the structure, is similar to reported (Zhang et al., 2005) for 1,6-dimethylphenanthro[1,2-b]furan-10,11-dione, the C11—C12 bond distance agree with the corresponding distance of 1.566 (2)Å. Intermolecular C—H···O non-classical hydrogen bonds are observed in the crystal structure (Table 1), which form a three-dimensional supramolecular framework (Fig. 2).