7,7',8,8'-Tetra-meth-oxy-4,4'-dimethyl-3,3'-bicoumarin.

In the crystal structure, the title compound, C(24)H(22)O(8), lies on a twofold rotation axis and the asymmetric unit comprises one half-mol-ecule. The dihedral angle formed by the coumarin unit with the symmetry-related part is 74.78 (14)°. One of the meth-oxy groups attached to the coumarin unit is considerably twisted, making an angle of 87.17 (17)° with respect to the coumarin unit; the other is twisted by 0.66 (19)°. No classical hydrogen bonds are found in the sturcture; only a weak C-H⋯π inter-action and short intra-molecular O⋯O contacts [2.683 (2)-2.701 (2) Å] are observed.

Related literature

For the biological activity of coumarins, see: El-Agrody et al. (2001 ▶); El-Farargy (1991 ▶); Emmanuel-Giota et al. (2001 ▶); Ghate et al. (2005 ▶); Laakso et al. (1994 ▶); Nofal et al. (2000 ▶); Pratibha & Shreeya (1999 ▶); Shaker (1996 ▶); Yang et al. (2005 ▶). For the pharmaceutical properties of coumarin derivatives, see: Kennedy & Thornes (1997 ▶). For natural and synthetic coumarins, see: Carlton et al. (1996 ▶); Zhou et al. (2000 ▶). For related bond-length data, see: Allen et al. (1987 ▶). For stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 ▶).

Experimental

Crystal data

C24H22O8

M = 438.42

Monoclinic,

a = 21.715 (9) Å

b = 7.138 (3) Å

c = 15.511 (6) Å

β = 121.801 (5)°

V = 2043.3 (14) Å3

Z = 4

Mo Kα radiation

μ = 0.11 mm−1

T = 100 K

0.28 × 0.19 × 0.06 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (; Bruker, 2005 ▶) T min = 0.971, T max = 0.994

27961 measured reflections

3527 independent reflections

2710 reflections with I > 2σ(I)

R int = 0.065

Refinement

R[F 2 > 2σ(F 2)] = 0.059

wR(F 2) = 0.155

S = 1.08

3527 reflections

189 parameters

All H-atom parameters refined

Δρmax = 0.50 e Å−3

Δρmin = −0.21 e Å−3

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: SAINT (Bruker, 2005 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809017334/is2417sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809017334/is2417Isup2.hkl

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

C24H22O8	F(000) = 920
Mr = 438.42	Dx = 1.425 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 6562 reflections
a = 21.715 (9) Å	θ = 2.7–31.8°
b = 7.138 (3) Å	µ = 0.11 mm−1
c = 15.511 (6) Å	T = 100 K
β = 121.801 (5)°	Plate, colourless
V = 2043.3 (14) Å3	0.28 × 0.19 × 0.06 mm
Z = 4

Bruker SMART APEXII CCD area-detector diffractometer	3527 independent reflections
Radiation source: fine-focus sealed tube	2710 reflections with I > 2σ(I)
graphite	Rint = 0.065
φ and ω scans	θmax = 32.0°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −32→32
Tmin = 0.971, Tmax = 0.994	k = −10→10
27961 measured reflections	l = −23→23

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)] = 0.059	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.155	All H-atom parameters refined
S = 1.08	w = 1/[σ2(Fo2) + (0.0752P)2 + 1.2567P] where P = (Fo2 + 2Fc2)/3
3527 reflections	(Δ/σ)max < 0.001
189 parameters	Δρmax = 0.50 e Å−3
0 restraints	Δρmin = −0.21 e Å−3

Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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	0.15443 (5)	0.04445 (13)	0.38705 (7)	0.0178 (2)
O2	0.05473 (6)	−0.06775 (15)	0.37300 (8)	0.0242 (2)
O3	0.30066 (5)	0.03278 (14)	0.48961 (7)	0.0212 (2)
O4	0.37511 (5)	0.26053 (15)	0.43926 (8)	0.0221 (2)
C1	0.08045 (7)	0.05014 (19)	0.34517 (10)	0.0175 (3)
C2	0.03949 (7)	0.19639 (19)	0.27048 (10)	0.0163 (3)
C3	0.07228 (7)	0.32194 (19)	0.24158 (10)	0.0168 (3)
C4	0.15015 (7)	0.31354 (18)	0.28870 (10)	0.0161 (3)
C5	0.19034 (8)	0.44106 (19)	0.26927 (10)	0.0185 (3)
C6	0.26498 (8)	0.42852 (19)	0.31768 (11)	0.0194 (3)
C7	0.30199 (7)	0.28719 (19)	0.38881 (10)	0.0174 (3)
C8	0.26401 (7)	0.15966 (18)	0.41265 (9)	0.0164 (3)
C9	0.18892 (7)	0.17416 (18)	0.36139 (10)	0.0154 (2)
C10	0.30773 (13)	−0.1493 (2)	0.45770 (15)	0.0362 (4)
C11	0.41539 (8)	0.3869 (2)	0.41549 (13)	0.0267 (3)
C12	0.02974 (8)	0.4697 (2)	0.16315 (12)	0.0247 (3)
H5	0.1654 (10)	0.540 (3)	0.2226 (15)	0.024 (5)*
H6	0.2908 (11)	0.516 (3)	0.3016 (16)	0.033 (5)*
H10A	0.3396 (14)	−0.139 (4)	0.429 (2)	0.063 (8)*
H10B	0.3324 (13)	−0.224 (3)	0.514 (2)	0.046 (6)*
H10C	0.2573 (16)	−0.202 (4)	0.410 (2)	0.067 (8)*
H11A	0.3985 (12)	0.382 (3)	0.3405 (19)	0.044 (6)*
H11B	0.4125 (11)	0.519 (3)	0.4338 (15)	0.028 (5)*
H11C	0.4642 (10)	0.340 (3)	0.4535 (14)	0.022 (4)*
H12A	0.0472 (11)	0.483 (3)	0.1149 (17)	0.035 (5)*
H12B	0.0359 (12)	0.591 (3)	0.1955 (18)	0.041 (6)*
H12C	−0.0217 (12)	0.440 (3)	0.1264 (17)	0.036 (5)*

	U11	U22	U33	U12	U13	U23
O1	0.0162 (5)	0.0193 (5)	0.0163 (4)	0.0013 (3)	0.0074 (4)	0.0050 (4)
O2	0.0213 (5)	0.0253 (5)	0.0244 (5)	−0.0003 (4)	0.0111 (4)	0.0083 (4)
O3	0.0217 (5)	0.0219 (5)	0.0134 (4)	0.0047 (4)	0.0048 (4)	0.0029 (4)
O4	0.0144 (5)	0.0250 (5)	0.0230 (5)	−0.0015 (4)	0.0071 (4)	−0.0020 (4)
C1	0.0167 (6)	0.0199 (6)	0.0149 (6)	0.0003 (5)	0.0076 (5)	0.0008 (5)
C2	0.0155 (6)	0.0179 (6)	0.0140 (6)	0.0004 (4)	0.0067 (5)	−0.0003 (4)
C3	0.0166 (6)	0.0176 (6)	0.0145 (6)	0.0013 (4)	0.0071 (5)	0.0018 (4)
C4	0.0166 (6)	0.0174 (6)	0.0133 (5)	0.0013 (4)	0.0072 (5)	0.0009 (4)
C5	0.0199 (6)	0.0185 (6)	0.0165 (6)	0.0007 (5)	0.0091 (5)	0.0027 (5)
C6	0.0202 (6)	0.0200 (6)	0.0186 (6)	−0.0016 (5)	0.0106 (5)	−0.0002 (5)
C7	0.0142 (6)	0.0211 (6)	0.0143 (6)	−0.0007 (4)	0.0058 (5)	−0.0037 (5)
C8	0.0168 (6)	0.0176 (6)	0.0108 (5)	0.0018 (4)	0.0045 (5)	−0.0003 (4)
C9	0.0175 (6)	0.0155 (6)	0.0125 (5)	−0.0012 (4)	0.0075 (5)	−0.0006 (4)
C10	0.0564 (12)	0.0239 (8)	0.0302 (9)	0.0173 (8)	0.0241 (9)	0.0093 (7)
C11	0.0188 (7)	0.0267 (8)	0.0339 (8)	−0.0059 (6)	0.0134 (6)	−0.0047 (6)
C12	0.0183 (7)	0.0265 (7)	0.0254 (7)	0.0030 (5)	0.0089 (6)	0.0112 (6)

O1—C9	1.3750 (16)	C5—H5	0.952 (19)
O1—C1	1.3801 (17)	C6—C7	1.395 (2)
O2—C1	1.2085 (17)	C6—H6	0.96 (2)
O3—C8	1.3701 (16)	C7—C8	1.4025 (19)
O3—C10	1.428 (2)	C8—C9	1.3912 (19)
O4—C7	1.3640 (17)	C10—H10A	1.01 (3)
O4—C11	1.4334 (19)	C10—H10B	0.92 (3)
C1—C2	1.4618 (19)	C10—H10C	1.02 (3)
C2—C3	1.3592 (19)	C11—H11A	1.02 (2)
C2—C2i	1.482 (3)	C11—H11B	1.00 (2)
C3—C4	1.4472 (19)	C11—H11C	0.963 (19)
C3—C12	1.5036 (19)	C12—H12A	1.01 (2)
C4—C5	1.3993 (19)	C12—H12B	0.97 (2)
C4—C9	1.4034 (18)	C12—H12C	0.97 (2)
C5—C6	1.384 (2)
C9—O1—C1	121.36 (10)	O3—C8—C9	121.00 (12)
C8—O3—C10	114.77 (12)	O3—C8—C7	120.42 (12)
C7—O4—C11	116.63 (12)	C9—C8—C7	118.42 (12)
O2—C1—O1	116.99 (12)	O1—C9—C8	115.95 (11)
O2—C1—C2	125.28 (13)	O1—C9—C4	121.49 (12)
O1—C1—C2	117.72 (11)	C8—C9—C4	122.56 (12)
C3—C2—C1	121.77 (12)	O3—C10—H10A	108.3 (16)
C3—C2—C2i	123.20 (11)	O3—C10—H10B	108.3 (15)
C1—C2—C2i	115.03 (10)	H10A—C10—H10B	106 (2)
C2—C3—C4	118.80 (12)	O3—C10—H10C	108.6 (16)
C2—C3—C12	121.60 (13)	H10A—C10—H10C	115 (2)
C4—C3—C12	119.59 (12)	H10B—C10—H10C	110 (2)
C5—C4—C9	117.13 (12)	O4—C11—H11A	111.7 (13)
C5—C4—C3	124.03 (12)	O4—C11—H11B	112.6 (11)
C9—C4—C3	118.80 (12)	H11A—C11—H11B	108.8 (17)
C6—C5—C4	121.74 (13)	O4—C11—H11C	104.2 (11)
C6—C5—H5	119.7 (11)	H11A—C11—H11C	107.7 (16)
C4—C5—H5	118.6 (11)	H11B—C11—H11C	111.8 (16)
C5—C6—C7	119.83 (13)	C3—C12—H12A	111.0 (12)
C5—C6—H6	119.7 (13)	C3—C12—H12B	110.3 (14)
C7—C6—H6	120.5 (13)	H12A—C12—H12B	107.2 (17)
O4—C7—C6	124.46 (12)	C3—C12—H12C	110.3 (12)
O4—C7—C8	115.26 (12)	H12A—C12—H12C	110.5 (18)
C6—C7—C8	120.28 (13)	H12B—C12—H12C	107.4 (17)
C9—O1—C1—O2	−179.03 (12)	C5—C6—C7—O4	178.75 (12)
C9—O1—C1—C2	1.45 (18)	C5—C6—C7—C8	−1.0 (2)
O2—C1—C2—C3	−178.65 (14)	C10—O3—C8—C9	87.17 (17)
O1—C1—C2—C3	0.83 (19)	C10—O3—C8—C7	−97.47 (17)
O2—C1—C2—C2i	1.3 (2)	O4—C7—C8—O3	6.82 (18)
O1—C1—C2—C2i	−179.20 (11)	C6—C7—C8—O3	−173.39 (12)
C1—C2—C3—C4	−2.0 (2)	O4—C7—C8—C9	−177.70 (11)
C2i—C2—C3—C4	178.01 (13)	C6—C7—C8—C9	2.09 (19)
C1—C2—C3—C12	178.72 (13)	C1—O1—C9—C8	176.73 (11)
C2i—C2—C3—C12	−1.3 (2)	C1—O1—C9—C4	−2.48 (18)
C2—C3—C4—C5	−176.43 (13)	O3—C8—C9—O1	−5.18 (18)
C12—C3—C4—C5	2.8 (2)	C7—C8—C9—O1	179.37 (11)
C2—C3—C4—C9	1.01 (19)	O3—C8—C9—C4	174.02 (12)
C12—C3—C4—C9	−179.71 (13)	C7—C8—C9—C4	−1.42 (19)
C9—C4—C5—C6	1.4 (2)	C5—C4—C9—O1	178.84 (11)
C3—C4—C5—C6	178.94 (13)	C3—C4—C9—O1	1.22 (19)
C4—C5—C6—C7	−0.8 (2)	C5—C4—C9—C8	−0.32 (19)
C11—O4—C7—C6	−0.66 (19)	C3—C4—C9—C8	−177.94 (12)
C11—O4—C7—C8	179.12 (12)

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···Cg1ii	0.96 (2)	2.86 (2)	3.676 (2)	143.5 (18)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C6—H6⋯Cg1i	0.96 (2)	2.86 (2)	3.676 (2)	143.5 (18)

Symmetry code: (i) . Cg1 is the centroid of the C4–C9 ring.