supplementary materials


kp2449 scheme

Acta Cryst. (2013). E69, o834    [ doi:10.1107/S1600536813011483 ]

2-Bromo-1,6,6-trimethyl-6,7,8,9-tetrahydrophenanthro[1,2-b]furan-10,11-dione

C.-P. Fan, W.-P. Yin, X.-X. Cao and J.-C. Yao

Abstract top

In the title compound, C19H17BrO3, the ring skeleton is located on a crystallographic mirror plane; two C atoms of the cyclohexene ring are disordered over the two locations to satisfy the preferred ring conformation. In the crystal, C-H...O hydrogen bonds link the molecules into chains along the a axis. [pi]-[pi] stacking interactions between benzoquinone rings, with a centroid-centroid distance of 3.7225 (4) Å, are also observed, which connect the chains into a two-dimensional networkparallel to the ab plane.

Comment top

The Chinese herbal medicine, danshen, comes from the dried root of Salvia miltiorrhiza Bunge and Salvia przewalskii Maxim(Labiatae). Tanshinone IIA is the major active component isolated from danshen, which has unique curative effect in treating coronary heart disease (Chang et al., 1991; Wang et al., 2005), antitumour (Ryu et al., 1997), myocardial infarction and angina pectoris (Xue et al., 1999). The title compound, C19H17BrO3, is derivative obtained by modification of Tanshinone IIA and may be used for obtaining molecules with higher bioactivity and better solubility.

The crystal structure of (I) contains three six-membered rings forming a phenanthrene dione system with a five-membered methylfuran ring fused to the dione ring (Fig. 1). The bond distance of C7-C8 agree with the corresponding distance of 1.564 (3) Å reported for 1,6,6-trimethyl-6,7,8,9-tetrahydrophenanthro[1,2-b]furan-10,11- -dione (Liu et al., 2007), indicating the nonconjugation system of the C3, C4, C7-C10 ring. The bond distance of Br1-C12 is 1.852 (3) Å. The ring skeleton is located at the crystallographic mirror plane except the atoms C15 and C16 which are disordered over two locations. Thus, the terminal six-membered ring is in a twist form with torsion angles C1-C2-C14-C15 = 19.8 (2)°, C1-C2-C16-C17 = 13.5 (2)°, the deviations of C15, C16, C18, C18A from the least square plane are 0.4867Å, -0.3383Å, -1.2396Å and 1.2396Å, respectively. Intermolecular C—H···O hydrogen bonds of d(O2···C6) = 3.322 (4) Å link the title molecules into a one-dimensional chain along the a axis (Table 1). The pi-pi stacking interactions between benzoquinone rings with the centroid-centroid distance of 3.7225 (4) Å [symmetry operations involved: 1-x,-1/2+y,-z;1-x,1/2+y-z;1-x,-1-y,-z;1-x,2-y,-z] are observed in the crystal structure.

Related literature top

The title compound is a derivative of Tanshinone IIA, the major active component isolated from the Chinese herbal medicine danshen, which is used in the treatment of coronary heart disease (Chang et al., 1991; Wang et al., 2005), myocardial infarction and angina pectoris (Xue et al., 1999) and has antitumour activity (Ryu et al., 1997). For the structure of 1,6,6-trimethyl-6,7,8,9-tetrahydrophenanthro[1,2-b]furan-10,11-dione, see: Liu & Gao (2007).

Experimental top

Tanshinone IIA (0.3 mmol) was added to dry dichloromethane(15 mL)in a three neck flask. The mixture was stirred and was heated to reflux temperature. And then, N-bromosuccinimide(0.36mmol) and benzoyl peroxide(0.03mmol) were dropped into the flask. After reflux reaction for 9h and left stirring about 17h at room temperature, the solvent in flask was evaporated. The residue was purified by column chromatography on silica gel with ethyl acetate/petroleum ether to afford the title compound solid (109 mg, yield 97.08%). The crimson crystals of the title compound for structure determination were obtained from recrystallization of the product from ethyl acetate at room temperature.

Refinement top

H1W and H2W were located by a difference map and refined isotropically. All of the remaining H atoms were positioned geometrically and treated as riding, with C—H bonding lengths constrained to 0.93 Å (aromatic CH) or 0.97 Å (methylene CH2), and with Uiso(H) = 1.2Ueq(C) or 1.5Ueq (methylene C).The carbon atoms of C15 and C16 located from the terminal cyclohexene ring and five hydrogen atoms H13a, H13b, H13c, H14a, H14b were observed disordered at two close positions with the half occupancy, respectively.

Computing details top

Data collection: SMART (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); 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).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), with atom labels and 50% probability displacement ellipsoids for non-H atoms. C15, C16 atoms are in disorder over two locations but one for each atom is shown. Symmetry code used for (C18a): x,-y+3/2,z.
2-Bromo-1,6,6-trimethyl-6,7,8,9-tetrahydrophenanthro[1,2-b]furan-10,11-dione top
Crystal data top
C19H17BrO3F(000) = 380
Mr = 373.24Dx = 1.541 Mg m3
Monoclinic, P21/mMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybCell parameters from 2150 reflections
a = 9.6063 (12) Åθ = 2.6–23.0°
b = 7.0457 (9) ŵ = 2.57 mm1
c = 11.9688 (15) ÅT = 296 K
β = 96.723 (1)°Block, brown
V = 804.52 (18) Å30.48 × 0.15 × 0.12 mm
Z = 2
Data collection top
Bruker SMART CCD area-detector
diffractometer
1634 independent reflections
Radiation source: fine-focus sealed tube1177 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.046
phi and ω scansθmax = 25.5°, θmin = 2.6°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
h = 1111
Tmin = 0.372, Tmax = 0.748k = 88
6178 measured reflectionsl = 1414
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.033Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.087H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0469P)2]
where P = (Fo2 + 2Fc2)/3
1634 reflections(Δ/σ)max < 0.001
144 parametersΔρmax = 0.22 e Å3
0 restraintsΔρmin = 0.41 e Å3
Crystal data top
C19H17BrO3V = 804.52 (18) Å3
Mr = 373.24Z = 2
Monoclinic, P21/mMo Kα radiation
a = 9.6063 (12) ŵ = 2.57 mm1
b = 7.0457 (9) ÅT = 296 K
c = 11.9688 (15) Å0.48 × 0.15 × 0.12 mm
β = 96.723 (1)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
1634 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
1177 reflections with I > 2σ(I)
Tmin = 0.372, Tmax = 0.748Rint = 0.046
6178 measured reflectionsθmax = 25.5°
Refinement top
R[F2 > 2σ(F2)] = 0.033H-atom parameters constrained
wR(F2) = 0.087Δρmax = 0.22 e Å3
S = 1.02Δρmin = 0.41 e Å3
1634 reflectionsAbsolute structure: ?
144 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes)

are estimated using the full covariance matrix. The cell esds are taken

into account individually in the estimation of esds in distances, angles

and torsion angles; correlations between esds in cell parameters are only

used when they are defined by crystal symmetry. An approximate (isotropic)

treatment of cell esds is used for estimating esds 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 > 2sigma(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
xyzUiso*/UeqOcc. (<1)
Br10.50666 (4)0.75000.40805 (3)0.0774 (2)
C10.9138 (3)0.75000.2002 (2)0.0392 (7)
C20.7711 (3)0.75000.2173 (2)0.0365 (7)
C30.6680 (3)0.75000.1229 (2)0.0354 (7)
C40.7082 (3)0.75000.0134 (2)0.0371 (7)
C50.8494 (3)0.75000.0014 (3)0.0462 (8)
H50.87660.75000.07340.055*
C60.9483 (3)0.75000.0909 (3)0.0471 (8)
H61.04250.75000.07980.057*
C70.5146 (3)0.75000.1357 (3)0.0456 (8)
C80.4040 (3)0.75000.0286 (3)0.0440 (8)
C90.4585 (3)0.75000.0783 (3)0.0405 (8)
C100.5998 (3)0.75000.0809 (3)0.0387 (7)
C110.3933 (3)0.75000.1926 (3)0.0435 (8)
C120.5002 (4)0.75000.2540 (3)0.0490 (8)
C130.2392 (4)0.75000.2319 (3)0.0590 (10)
H13A0.20170.87440.22220.088*0.50
H13B0.19300.66010.18860.088*0.50
H13C0.22440.71550.31000.088*0.50
C140.7287 (4)0.75000.3362 (3)0.0513 (9)
H14A0.71330.62520.33530.062*0.50
H14B0.64360.82370.35300.062*0.50
C150.8496 (5)0.8191 (7)0.4235 (4)0.0587 (15)0.50
H15B0.87510.95090.41440.070*0.50
H15A0.82190.80360.49830.070*0.50
C160.9772 (5)0.7020 (8)0.4095 (3)0.058 (2)0.50
H16A0.94940.56960.40790.070*0.50
H16B1.04970.72070.47210.070*0.50
C171.0334 (3)0.75000.2971 (3)0.0495 (8)
C181.1253 (3)0.5741 (4)0.2885 (2)0.0726 (8)
H18A1.19980.57400.34940.109*
H18B1.16410.57600.21820.109*
H18C1.06940.46190.29250.109*
O10.4673 (3)0.75000.2239 (2)0.0881 (10)
O20.2812 (3)0.75000.0408 (2)0.0763 (8)
O30.6299 (2)0.75000.18897 (17)0.0468 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0776 (4)0.1056 (4)0.0470 (3)0.0000.0020 (2)0.000
C10.0356 (18)0.0377 (18)0.0443 (18)0.0000.0051 (14)0.000
C20.0394 (18)0.0273 (16)0.0436 (18)0.0000.0093 (14)0.000
C30.0328 (17)0.0327 (16)0.0422 (17)0.0000.0107 (14)0.000
C40.0293 (17)0.0391 (17)0.0435 (17)0.0000.0072 (14)0.000
C50.0348 (19)0.063 (2)0.0420 (18)0.0000.0106 (15)0.000
C60.0283 (17)0.064 (2)0.050 (2)0.0000.0080 (14)0.000
C70.0374 (19)0.0464 (19)0.0548 (19)0.0000.0126 (16)0.000
C80.0323 (19)0.0402 (18)0.060 (2)0.0000.0093 (16)0.000
C90.0304 (18)0.0346 (17)0.056 (2)0.0000.0041 (15)0.000
C100.0386 (19)0.0378 (17)0.0401 (18)0.0000.0062 (14)0.000
C110.0397 (19)0.0343 (18)0.055 (2)0.0000.0023 (16)0.000
C120.046 (2)0.051 (2)0.048 (2)0.0000.0043 (17)0.000
C130.045 (2)0.047 (2)0.080 (3)0.0000.0106 (19)0.000
C140.048 (2)0.061 (2)0.0461 (19)0.0000.0119 (16)0.000
C150.069 (3)0.066 (4)0.042 (3)0.001 (2)0.012 (2)0.005 (2)
C160.060 (3)0.069 (8)0.042 (2)0.004 (3)0.008 (2)0.006 (2)
C170.0395 (19)0.059 (2)0.049 (2)0.0000.0007 (15)0.000
C180.0569 (17)0.0664 (19)0.089 (2)0.0088 (14)0.0157 (14)0.0102 (15)
O10.0423 (15)0.174 (3)0.0517 (16)0.0000.0206 (13)0.000
O20.0311 (15)0.124 (2)0.0759 (18)0.0000.0144 (13)0.000
O30.0378 (13)0.0616 (15)0.0409 (13)0.0000.0045 (10)0.000
Geometric parameters (Å, º) top
Br1—C121.852 (3)C13—H13A0.9600
C1—C61.386 (4)C13—H13B0.9600
C1—C21.410 (4)C13—H13C0.9600
C1—C171.534 (4)C14—C15i1.547 (5)
C2—C31.412 (4)C14—C151.547 (5)
C2—C141.526 (4)C14—H14A0.8918
C3—C41.409 (4)C14—H14B1.0084
C3—C71.499 (4)C15—C15i0.973 (9)
C4—C51.388 (4)C15—C16i1.265 (6)
C4—C101.444 (4)C15—C161.503 (6)
C5—C61.371 (4)C15—H15B0.9700
C5—H50.9300C15—H15A0.9700
C6—H60.9300C16—C16i0.677 (12)
C7—O11.197 (4)C16—C15i1.265 (6)
C7—C81.566 (5)C16—C171.545 (5)
C8—O21.205 (4)C16—H16A0.9700
C8—C91.439 (4)C16—H16B0.9700
C9—C101.361 (4)C17—C18i1.532 (3)
C9—C111.436 (4)C17—C181.532 (3)
C10—O31.358 (3)C17—C16i1.545 (5)
C11—C121.331 (5)C18—H18A0.9600
C11—C131.499 (4)C18—H18B0.9600
C12—O31.389 (4)C18—H18C0.9600
C6—C1—C2118.7 (3)C15—C14—H14B105.4
C6—C1—C17118.2 (3)H14A—C14—H14B111.9
C2—C1—C17123.1 (3)C15i—C15—C16i83.3 (3)
C1—C2—C3119.2 (3)C15i—C15—C1656.7 (3)
C1—C2—C14120.3 (3)C16i—C15—C1626.6 (5)
C3—C2—C14120.5 (3)C15i—C15—C1471.66 (18)
C4—C3—C2120.0 (3)C16i—C15—C14122.4 (4)
C4—C3—C7118.4 (3)C16—C15—C14108.0 (3)
C2—C3—C7121.6 (3)C15i—C15—H15B163.3
C5—C4—C3119.8 (3)C16i—C15—H15B80.6
C5—C4—C10121.8 (3)C16—C15—H15B107.0
C3—C4—C10118.4 (3)C14—C15—H15B113.9
C6—C5—C4119.5 (3)C15i—C15—H15A83.5
C6—C5—H5120.2C16i—C15—H15A118.9
C4—C5—H5120.2C16—C15—H15A110.9
C5—C6—C1122.7 (3)C14—C15—H15A108.8
C5—C6—H6118.6H15B—C15—H15A108.2
C1—C6—H6118.6C16i—C16—C15i96.7 (3)
O1—C7—C3124.7 (3)C16i—C16—C1556.7 (3)
O1—C7—C8115.5 (3)C15i—C16—C1540.0 (4)
C3—C7—C8119.8 (3)C16i—C16—C1777.4 (2)
O2—C8—C9124.8 (3)C15i—C16—C17125.7 (4)
O2—C8—C7118.7 (3)C15—C16—C17110.5 (4)
C9—C8—C7116.4 (3)C16i—C16—H16A164.1
C10—C9—C11107.7 (3)C15i—C16—H16A67.7
C10—C9—C8119.2 (3)C15—C16—H16A107.7
C11—C9—C8133.1 (3)C17—C16—H16A108.5
O3—C10—C9110.2 (3)C16i—C16—H16B82.2
O3—C10—C4122.0 (3)C15i—C16—H16B122.2
C9—C10—C4127.8 (3)C15—C16—H16B111.1
C12—C11—C9104.3 (3)C17—C16—H16B110.5
C12—C11—C13128.6 (3)H16A—C16—H16B108.5
C9—C11—C13127.1 (3)C18i—C17—C18108.0 (3)
C11—C12—O3112.9 (3)C18i—C17—C1109.60 (18)
C11—C12—Br1131.9 (3)C18—C17—C1109.60 (18)
O3—C12—Br1115.2 (2)C18i—C17—C16i98.3 (3)
C11—C13—H13A109.5C18—C17—C16i119.9 (3)
C11—C13—H13B109.5C1—C17—C16i110.6 (3)
H13A—C13—H13B109.5C18i—C17—C16119.9 (3)
C11—C13—H13C109.5C18—C17—C1698.3 (3)
H13A—C13—H13C109.5C1—C17—C16110.6 (3)
H13B—C13—H13C109.5C16i—C17—C1625.3 (4)
C2—C14—C15i111.7 (3)C17—C18—H18A109.5
C2—C14—C15111.7 (3)C17—C18—H18B109.5
C15i—C14—C1536.7 (4)H18A—C18—H18B109.5
C2—C14—H14A92.9C17—C18—H18C109.5
C15i—C14—H14A79.0H18A—C18—H18C109.5
C15—C14—H14A115.4H18B—C18—H18C109.5
C2—C14—H14B119.8C10—O3—C12104.9 (2)
C15i—C14—H14B126.1
C6—C1—C2—C30.0C13—C11—C12—O3180.0
C17—C1—C2—C3180.0C9—C11—C12—Br1180.0
C6—C1—C2—C14180.0C13—C11—C12—Br10.0
C17—C1—C2—C140.0C1—C2—C14—C15i19.8 (2)
C1—C2—C3—C40.0C3—C2—C14—C15i160.2 (2)
C14—C2—C3—C4180.0C1—C2—C14—C1519.8 (2)
C1—C2—C3—C7180.0C3—C2—C14—C15160.2 (2)
C14—C2—C3—C70.0C2—C14—C15—C15i97.56 (14)
C2—C3—C4—C50.000 (1)C2—C14—C15—C16i28.5 (5)
C7—C3—C4—C5180.0C15i—C14—C15—C16i69.1 (5)
C2—C3—C4—C10180.0C2—C14—C15—C1653.3 (4)
C7—C3—C4—C100.0C15i—C14—C15—C1644.3 (3)
C3—C4—C5—C60.000 (1)C15i—C15—C16—C16i180.000 (2)
C10—C4—C5—C6180.0C14—C15—C16—C16i127.6 (4)
C4—C5—C6—C10.0C16i—C15—C16—C15i180.000 (1)
C2—C1—C6—C50.0C14—C15—C16—C15i52.4 (4)
C17—C1—C6—C5180.0C15i—C15—C16—C17121.6 (4)
C4—C3—C7—O1180.0C16i—C15—C16—C1758.4 (4)
C2—C3—C7—O10.0C14—C15—C16—C1769.2 (4)
C4—C3—C7—C80.0C6—C1—C17—C18i59.21 (19)
C2—C3—C7—C8180.0C2—C1—C17—C18i120.79 (19)
O1—C7—C8—O20.0C6—C1—C17—C1859.21 (19)
C3—C7—C8—O2180.0C2—C1—C17—C18120.79 (19)
O1—C7—C8—C9180.0C6—C1—C17—C16i166.5 (2)
C3—C7—C8—C90.0C2—C1—C17—C16i13.5 (2)
O2—C8—C9—C10180.0C6—C1—C17—C16166.5 (2)
C7—C8—C9—C100.0C2—C1—C17—C1613.5 (2)
O2—C8—C9—C110.0C16i—C16—C17—C18i34.1 (2)
C7—C8—C9—C11180.0C15i—C16—C17—C18i123.4 (5)
C11—C9—C10—O30.0C15—C16—C17—C18i81.0 (4)
C8—C9—C10—O3180.0C16i—C16—C17—C18150.55 (19)
C11—C9—C10—C4180.0C15i—C16—C17—C18120.2 (6)
C8—C9—C10—C40.0C15—C16—C17—C18162.6 (3)
C5—C4—C10—O30.0C16i—C16—C17—C194.83 (11)
C3—C4—C10—O3180.0C15i—C16—C17—C15.6 (6)
C5—C4—C10—C9180.0C15—C16—C17—C148.0 (4)
C3—C4—C10—C90.0C15i—C16—C17—C16i89.2 (6)
C10—C9—C11—C120.0C15—C16—C17—C16i46.8 (4)
C8—C9—C11—C12180.0C9—C10—O3—C120.0
C10—C9—C11—C13180.0C4—C10—O3—C12180.0
C8—C9—C11—C130.0C11—C12—O3—C100.0
C9—C11—C12—O30.0Br1—C12—O3—C10180.0
Symmetry code: (i) x, y+3/2, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···O2ii0.932.393.322 (4)177
Symmetry code: (ii) x+1, y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···O2i0.932.393.322 (4)177.0
Symmetry code: (i) x+1, y, z.
Acknowledgements top

We are grateful for financial support from the Natural Science Foundation of Henan Province of China (092102310075).

references
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