10-(3,4-Dimethoxy­benzyl­idene)anthrone

Zhou, W.; Hu, W.; Xia, C.

doi:10.1107/S1600536805028278

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10-(3,4-Dimethoxybenzylidene)anthrone

W. Zhou, W. Hu and C. Xia

The title compound, C₂₃H₁₈O₃, was prepared from anthrone and 3,4-dimethoxybenzaldehyde in the presence of pyridine. X-ray analysis shows that the three rings of the anthraquinone moiety are not coplanar; the central six-membered ring assumes an asymmetric boat conformation in which the carbonyl C and the opposite C atom deviate from the plane by 0.190 (3) and 0.262 (3) Å, respectively.

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536805028278/ob6581sup1.cif Contains datablocks global, I
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536805028278/ob6581Isup2.hkl Contains datablock I

CCDC reference: 282603

checkCIF report

Key indicators

Single-crystal X-ray study
T = 295 K
Mean (C-C)= 0.003 Å
R factor = 0.035
wR factor = 0.110
Data-to-parameter ratio = 13.2

checkCIF/PLATON results

No syntax errors found


No errors found in this datablock

Comment top

10-Substituted benzylideneanthrones have been known for a long time for their widespread use as functional dyes and disperse dyes (Day, 1963). Recently, however, some 10-substituted benzylideneanthrones have been found to possess high antitumor activity (Paull et al., 1992; Prinz et al., 2003). Owing to our interest in this area, we have prepared a series of 10-substituted benzylideneanthrones and evaluated their anticancer activity. Our study on the structure–activity relationship (SAR) showed that a substitutent in the benzene moiety of the molecule affects the antitumor activity (Hu & Zhou, 2004). In a continuation of our research on SAR, we prepared the title compound, (I), and investigated its structure.

The molecular structure of (I) is illustrated in Fig. 1, and selected bond lengths and angles are listed in Table 1. The three rings of the anthraquinone moiety are not coplanar, the dihedral angle between the two outer benzene rings being 24.68 (9)°. In the central six-membered ring, atoms C11/C12/C13/C14 are planar within 0.0083 (9) Å, atoms C5 and C10 deviating from the plane by 0.262 (3) and 0.190 (3) Å, respectively; the ring assumes an asymmetric boat conformation.

Experimental top

To a mixture of anthrone (2.0 g, 10 mmol) and 3,4-dimethoxybenzaldehyde (2.0 g, 12 mmol) were added pyridine (30 ml) and piperidine (0.5 g, 6 mmol). The reaction mixture was refluxed for 6 h and thin-layer chromatography showed that the reaction was complete. The mixture was cooled to room temperature, poured into methanol (75 ml) and placed in a refrigerator overnight. The precipitate which formed was collected and recrystallized twice from glacial acetic acid to afford orange crystals of (I) (2.4 g, yield 70.2%, m.p. 453–456 K). Crystals suitable for X-ray analysis were grown from an ethanol solution by slow evaparation.

Computing details top

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS; data reduction: XCAD (McArdle, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXL97.

Figures top

Fig. 1. The structure of (I), shown with 50% probability displacement ellipsoids.

10-(3,4-Dimethoxybenzylidene)anthrone top

Crystal data top

C₂₃H₁₈O₃	F(000) = 720
M_r = 342.37	D_x = 1.305 Mg m⁻³
Monoclinic, P2₁/n	Melting point = 453–456 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 11.709 (3) Å	Cell parameters from 25 reflections
b = 10.306 (2) Å	θ = 10.7–14.0°
c = 14.847 (6) Å	µ = 0.09 mm⁻¹
β = 103.36 (3)°	T = 295 K
V = 1743.1 (9) Å³	Prismatic, orange
Z = 4	0.40 × 0.40 × 0.20 mm

Data collection top

Enraf–Nonius CAD-4 diffractometer	R_int = 0.021
Radiation source: fine-focus sealed tube	θ_max = 25.2°, θ_min = 2.0°
Graphite monochromator	h = −14→13
ω/2θ scans	k = 0→12
3529 measured reflections	l = −1→17
3136 independent reflections	3 standard reflections every 60 min
1832 reflections with I > 2σ(I)	intensity decay: none

Refinement top

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)] = 0.035	H-atom parameters constrained
wR(F²) = 0.110	w = 1/[σ²(F_o²) + (0.0484P)² + 0.3183P] where P = (F_o² + 2F_c²)/3
S = 0.99	(Δ/σ)_max < 0.001
3136 reflections	Δρ_max = 0.15 e Å⁻³
238 parameters	Δρ_min = −0.13 e Å⁻³
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0133 (12)

Crystal data top

C₂₃H₁₈O₃	V = 1743.1 (9) Å³
M_r = 342.37	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 11.709 (3) Å	µ = 0.09 mm⁻¹
b = 10.306 (2) Å	T = 295 K
c = 14.847 (6) Å	0.40 × 0.40 × 0.20 mm
β = 103.36 (3)°

Data collection top

Enraf–Nonius CAD-4 diffractometer	R_int = 0.021
3529 measured reflections	3 standard reflections every 60 min
3136 independent reflections	intensity decay: none
1832 reflections with I > 2σ(I)

Refinement top

R[F² > 2σ(F²)] = 0.035	0 restraints
wR(F²) = 0.110	H-atom parameters constrained
S = 0.99	Δρ_max = 0.15 e Å⁻³
3136 reflections	Δρ_min = −0.13 e Å⁻³
238 parameters

Special details top

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.

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

	x	y	z	U_iso*/U_eq
O1	−0.07769 (13)	0.91670 (16)	0.26699 (11)	0.0853 (5)
O2	0.48952 (12)	0.24924 (13)	0.60172 (9)	0.0618 (4)
O3	0.45078 (12)	0.13957 (13)	0.44370 (9)	0.0628 (4)
C1	0.07187 (19)	1.0518 (2)	0.41341 (15)	0.0614 (6)
H1	0.0141	1.1001	0.3740	0.074*
C2	0.1505 (2)	1.1133 (2)	0.48267 (16)	0.0665 (6)
H2	0.1465	1.2026	0.4902	0.080*
C3	0.2351 (2)	1.0416 (2)	0.54095 (16)	0.0669 (6)
H3	0.2884	1.0828	0.5886	0.080*
C4	0.24224 (17)	0.90959 (18)	0.52979 (15)	0.0587 (5)
H4	0.3006	0.8631	0.5701	0.070*
C5	0.17147 (15)	0.70174 (17)	0.44396 (12)	0.0448 (4)
C6	0.03917 (17)	0.5061 (2)	0.40338 (14)	0.0565 (5)
H6	0.0957	0.4547	0.4414	0.068*
C7	−0.0657 (2)	0.4513 (2)	0.35799 (16)	0.0725 (7)
H7	−0.0794	0.3636	0.3659	0.087*
C8	−0.1508 (2)	0.5259 (3)	0.30062 (17)	0.0828 (8)
H8	−0.2210	0.4883	0.2694	0.099*
C9	−0.13106 (18)	0.6547 (3)	0.29017 (16)	0.0739 (7)
H9	−0.1883	0.7047	0.2516	0.089*
C10	−0.01277 (16)	0.8539 (2)	0.32866 (14)	0.0576 (5)
C11	0.16388 (14)	0.84343 (17)	0.45934 (12)	0.0454 (5)
C12	0.06211 (15)	0.63806 (18)	0.39324 (12)	0.0451 (4)
C13	−0.02637 (15)	0.7128 (2)	0.33644 (13)	0.0523 (5)
C14	0.07668 (16)	0.91733 (18)	0.40075 (13)	0.0481 (5)
C15	0.27495 (15)	0.64083 (18)	0.47521 (14)	0.0533 (5)
H15	0.3329	0.6926	0.5114	0.064*
C16	0.31284 (15)	0.50738 (18)	0.46252 (13)	0.0489 (5)
C17	0.38052 (15)	0.44288 (18)	0.53917 (13)	0.0476 (5)
H17	0.3966	0.4832	0.5968	0.057*
C18	0.42387 (15)	0.32021 (17)	0.53070 (13)	0.0467 (5)
C19	0.40288 (16)	0.25983 (18)	0.44413 (13)	0.0494 (5)
C20	0.33782 (16)	0.3241 (2)	0.36780 (14)	0.0546 (5)
H20	0.3239	0.2850	0.3098	0.066*
C21	0.29319 (17)	0.4466 (2)	0.37722 (14)	0.0570 (5)
H21	0.2492	0.4887	0.3253	0.068*
C22	0.5087 (2)	0.3023 (2)	0.69236 (13)	0.0698 (6)
H22A	0.5503	0.3829	0.6946	0.105*
H22B	0.5542	0.2426	0.7359	0.105*
H22C	0.4346	0.3172	0.7078	0.105*
C23	0.4107 (2)	0.0596 (2)	0.36466 (14)	0.0699 (6)
H23A	0.3265	0.0549	0.3507	0.105*
H23B	0.4429	−0.0260	0.3771	0.105*
H23C	0.4356	0.0958	0.3128	0.105*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0625 (9)	0.1013 (13)	0.0794 (11)	0.0244 (9)	−0.0095 (8)	0.0270 (9)
O2	0.0731 (9)	0.0504 (8)	0.0519 (8)	0.0149 (7)	−0.0063 (7)	0.0021 (6)
O3	0.0668 (9)	0.0524 (9)	0.0625 (9)	0.0157 (7)	0.0013 (7)	−0.0076 (7)
C1	0.0639 (13)	0.0565 (13)	0.0679 (14)	0.0192 (11)	0.0233 (12)	0.0193 (11)
C2	0.0793 (15)	0.0455 (12)	0.0806 (16)	0.0017 (11)	0.0310 (13)	0.0040 (12)
C3	0.0685 (14)	0.0534 (13)	0.0768 (15)	−0.0080 (11)	0.0126 (12)	−0.0049 (11)
C4	0.0511 (11)	0.0513 (13)	0.0680 (14)	0.0001 (10)	0.0022 (10)	0.0022 (10)
C5	0.0391 (10)	0.0456 (11)	0.0468 (10)	0.0013 (8)	0.0038 (8)	0.0056 (8)
C6	0.0514 (11)	0.0573 (12)	0.0617 (13)	−0.0074 (10)	0.0146 (10)	−0.0070 (10)
C7	0.0646 (14)	0.0737 (15)	0.0836 (16)	−0.0243 (13)	0.0260 (13)	−0.0247 (13)
C8	0.0466 (12)	0.108 (2)	0.0897 (18)	−0.0194 (15)	0.0080 (12)	−0.0369 (17)
C9	0.0409 (11)	0.105 (2)	0.0680 (15)	0.0044 (13)	−0.0044 (10)	−0.0178 (14)
C10	0.0402 (10)	0.0776 (15)	0.0537 (13)	0.0170 (11)	0.0084 (9)	0.0113 (11)
C11	0.0383 (9)	0.0463 (11)	0.0506 (11)	0.0025 (9)	0.0082 (8)	0.0060 (9)
C12	0.0369 (9)	0.0536 (12)	0.0439 (10)	0.0004 (9)	0.0078 (8)	−0.0030 (9)
C13	0.0367 (10)	0.0701 (14)	0.0479 (11)	0.0040 (9)	0.0054 (9)	−0.0040 (10)
C14	0.0424 (10)	0.0509 (12)	0.0523 (11)	0.0096 (9)	0.0135 (9)	0.0089 (9)
C15	0.0420 (10)	0.0475 (12)	0.0626 (13)	0.0007 (9)	−0.0040 (9)	0.0010 (9)
C16	0.0373 (9)	0.0460 (11)	0.0589 (12)	0.0030 (8)	0.0016 (9)	0.0040 (9)
C17	0.0412 (10)	0.0457 (11)	0.0512 (11)	0.0002 (8)	0.0010 (8)	−0.0023 (9)
C18	0.0391 (9)	0.0438 (11)	0.0524 (11)	0.0016 (8)	0.0003 (8)	0.0034 (9)
C19	0.0433 (10)	0.0477 (11)	0.0550 (12)	0.0048 (9)	0.0071 (9)	0.0010 (9)
C20	0.0519 (11)	0.0604 (13)	0.0475 (11)	0.0054 (10)	0.0029 (9)	−0.0025 (10)
C21	0.0492 (11)	0.0601 (13)	0.0552 (12)	0.0092 (10)	−0.0012 (9)	0.0093 (11)
C22	0.0871 (16)	0.0647 (14)	0.0482 (12)	0.0083 (12)	−0.0040 (11)	0.0039 (11)
C23	0.0906 (17)	0.0575 (13)	0.0605 (14)	0.0118 (12)	0.0149 (12)	−0.0117 (11)

Geometric parameters (Å, º) top

O1—C10	1.230 (2)	C9—C13	1.394 (3)
O2—C18	1.365 (2)	C9—H9	0.9300
O2—C22	1.421 (2)	C10—C14	1.467 (3)
O3—C19	1.361 (2)	C10—C13	1.471 (3)
O3—C23	1.422 (2)	C11—C14	1.403 (2)
C1—C2	1.367 (3)	C12—C13	1.405 (2)
C1—C14	1.401 (3)	C15—C16	1.471 (3)
C1—H1	0.9300	C15—H15	0.9300
C2—C3	1.371 (3)	C16—C21	1.384 (3)
C2—H2	0.9300	C16—C17	1.396 (2)
C3—C4	1.376 (3)	C17—C18	1.379 (2)
C3—H3	0.9300	C17—H17	0.9300
C4—C11	1.399 (3)	C18—C19	1.398 (3)
C4—H4	0.9300	C19—C20	1.380 (3)
C5—C15	1.348 (2)	C20—C21	1.386 (3)
C5—C12	1.480 (2)	C20—H20	0.9300
C5—C11	1.484 (3)	C21—H21	0.9300
C6—C7	1.378 (3)	C22—H22A	0.9599
C6—C12	1.401 (3)	C22—H22B	0.9599
C6—H6	0.9300	C22—H22C	0.9599
C7—C8	1.385 (3)	C23—H23A	0.9599
C7—H7	0.9300	C23—H23B	0.9599
C8—C9	1.362 (3)	C23—H23C	0.9599
C8—H8	0.9300

C18—O2—C22	117.57 (15)	C9—C13—C10	118.97 (19)
C19—O3—C23	118.29 (15)	C12—C13—C10	120.73 (17)
C2—C1—C14	121.2 (2)	C1—C14—C11	119.97 (19)
C2—C1—H1	119.4	C1—C14—C10	119.62 (18)
C14—C1—H1	119.4	C11—C14—C10	120.35 (17)
C1—C2—C3	119.2 (2)	C5—C15—C16	131.69 (18)
C1—C2—H2	120.4	C5—C15—H15	114.2
C3—C2—H2	120.4	C16—C15—H15	114.2
C2—C3—C4	120.8 (2)	C21—C16—C17	118.28 (17)
C2—C3—H3	119.6	C21—C16—C15	123.32 (17)
C4—C3—H3	119.6	C17—C16—C15	118.17 (18)
C3—C4—C11	121.65 (19)	C18—C17—C16	120.92 (18)
C3—C4—H4	119.2	C18—C17—H17	119.5
C11—C4—H4	119.2	C16—C17—H17	119.5
C15—C5—C12	124.86 (17)	O2—C18—C17	125.05 (17)
C15—C5—C11	119.09 (16)	O2—C18—C19	114.82 (16)
C12—C5—C11	116.04 (15)	C17—C18—C19	120.12 (17)
C7—C6—C12	121.1 (2)	O3—C19—C20	125.66 (18)
C7—C6—H6	119.4	O3—C19—C18	115.12 (16)
C12—C6—H6	119.4	C20—C19—C18	119.21 (18)
C6—C7—C8	120.4 (2)	C19—C20—C21	120.25 (19)
C6—C7—H7	119.8	C19—C20—H20	119.9
C8—C7—H7	119.8	C21—C20—H20	119.9
C9—C8—C7	119.6 (2)	C16—C21—C20	121.20 (18)
C9—C8—H8	120.2	C16—C21—H21	119.4
C7—C8—H8	120.2	C20—C21—H21	119.4
C8—C9—C13	121.0 (2)	O2—C22—H22A	109.5
C8—C9—H9	119.5	O2—C22—H22B	109.5
C13—C9—H9	119.5	H22A—C22—H22B	109.5
O1—C10—C14	121.6 (2)	O2—C22—H22C	109.5
O1—C10—C13	121.3 (2)	H22A—C22—H22C	109.5
C14—C10—C13	117.08 (16)	H22B—C22—H22C	109.5
C4—C11—C14	117.16 (17)	O3—C23—H23A	109.5
C4—C11—C5	122.85 (16)	O3—C23—H23B	109.5
C14—C11—C5	119.97 (16)	H23A—C23—H23B	109.5
C6—C12—C13	117.61 (18)	O3—C23—H23C	109.5
C6—C12—C5	122.71 (17)	H23A—C23—H23C	109.5
C13—C12—C5	119.57 (17)	H23B—C23—H23C	109.5
C9—C13—C12	120.2 (2)

C14—C1—C2—C3	−0.3 (3)	C4—C11—C14—C1	0.9 (3)
C1—C2—C3—C4	0.6 (3)	C5—C11—C14—C1	−177.93 (17)
C2—C3—C4—C11	−0.2 (3)	C4—C11—C14—C10	−176.50 (17)
C12—C6—C7—C8	0.4 (3)	C5—C11—C14—C10	4.7 (3)
C6—C7—C8—C9	−0.9 (4)	O1—C10—C14—C1	14.9 (3)
C7—C8—C9—C13	0.0 (4)	C13—C10—C14—C1	−161.51 (17)
C3—C4—C11—C14	−0.6 (3)	O1—C10—C14—C11	−167.72 (18)
C3—C4—C11—C5	178.21 (19)	C13—C10—C14—C11	15.9 (3)
C15—C5—C11—C4	−22.9 (3)	C12—C5—C15—C16	6.5 (3)
C12—C5—C11—C4	157.81 (17)	C11—C5—C15—C16	−172.7 (2)
C15—C5—C11—C14	155.82 (18)	C5—C15—C16—C21	48.2 (3)
C12—C5—C11—C14	−23.5 (2)	C5—C15—C16—C17	−137.3 (2)
C7—C6—C12—C13	1.0 (3)	C21—C16—C17—C18	−1.9 (3)
C7—C6—C12—C5	177.26 (18)	C15—C16—C17—C18	−176.59 (16)
C15—C5—C12—C6	26.4 (3)	C22—O2—C18—C17	4.1 (3)
C11—C5—C12—C6	−154.39 (17)	C22—O2—C18—C19	−176.72 (18)
C15—C5—C12—C13	−157.46 (19)	C16—C17—C18—O2	−179.21 (17)
C11—C5—C12—C13	21.8 (2)	C16—C17—C18—C19	1.6 (3)
C8—C9—C13—C12	1.5 (3)	C23—O3—C19—C20	−15.3 (3)
C8—C9—C13—C10	−175.3 (2)	C23—O3—C19—C18	164.97 (18)
C6—C12—C13—C9	−2.0 (3)	O2—C18—C19—O3	0.1 (2)
C5—C12—C13—C9	−178.32 (17)	C17—C18—C19—O3	179.34 (16)
C6—C12—C13—C10	174.80 (17)	O2—C18—C19—C20	−179.68 (17)
C5—C12—C13—C10	−1.5 (3)	C17—C18—C19—C20	−0.4 (3)
O1—C10—C13—C9	−17.1 (3)	O3—C19—C20—C21	179.76 (18)
C14—C10—C13—C9	159.28 (18)	C18—C19—C20—C21	−0.5 (3)
O1—C10—C13—C12	166.05 (18)	C17—C16—C21—C20	0.9 (3)
C14—C10—C13—C12	−17.5 (3)	C15—C16—C21—C20	175.36 (18)
C2—C1—C14—C11	−0.5 (3)	C19—C20—C21—C16	0.2 (3)
C2—C1—C14—C10	176.92 (18)

Experimental details

Crystal data
Chemical formula	C₂₃H₁₈O₃
M_r	342.37
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	295
a, b, c (Å)	11.709 (3), 10.306 (2), 14.847 (6)
β (°)	103.36 (3)
V (Å³)	1743.1 (9)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.40 × 0.40 × 0.20

Data collection
Diffractometer	Enraf–Nonius CAD-4 diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	3529, 3136, 1832
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.598

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.035, 0.110, 0.99
No. of reflections	3136
No. of parameters	238
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.15, −0.13

Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1994), CAD-4 EXPRESS, XCAD (McArdle, 2000), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEP-3 for Windows (Farrugia, 1997), SHELXL97.

Selected geometric parameters (Å, º) top

O1—C10	1.230 (2)	C10—C14	1.467 (3)
C5—C15	1.348 (2)	C10—C13	1.471 (3)
C5—C12	1.480 (2)	C11—C14	1.403 (2)
C5—C11	1.484 (3)	C12—C13	1.405 (2)

C15—C5—C12	124.86 (17)	C21—C16—C15	123.32 (17)
C15—C5—C11	119.09 (16)	C17—C16—C15	118.17 (18)
C5—C15—C16	131.69 (18)

C11—C5—C12—C13	21.8 (2)	C5—C11—C14—C10	4.7 (3)
C5—C12—C13—C10	−1.5 (3)	C12—C5—C15—C16	6.5 (3)
C14—C10—C13—C12	−17.5 (3)	C5—C15—C16—C21	48.2 (3)

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