2-Hydr­oxy-1-methoxy­anthraquinone monohydrate

Liu, Z.-M.; Jiao, Y.-Q.

doi:10.1107/S1600536809021254

organic compounds

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ISSN: 2056-9890

Volume 65| Part 7| July 2009| Page o1523

doi:10.1107/S1600536809021254

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2-Hydroxy-1-methoxyanthraquinone monohydrate

Zhi-Meng Liu ^a ^* and Yuan-Qi Jiao ^a

^aSchool of Materials Science and Engineering, South China University of Technology, Guangzhou 510641, People's Republic of China
^*Correspondence e-mail: liuzmeng2009@yahoo.com.cn

(Received 4 May 2009; accepted 4 June 2009; online 6 June 2009)

The title compound, C₁₅H₁₀O₄·H₂O, also known as alizarin 1-methyl ether monohydrate, was isolated from Morinda officinalis How. The anthraquinone ring system is almost planar, the dihedral angle between the two outer benzene rings being 3.07 (4)°. In the crystal structure, O—H⋯O hydrogen bonds link the organic molecules and the water molecules, forming a three-dimensional network.

Related literature

For pharmacological properties of anthraquinone derivatives, see: Kim et al. (2005 ) and of 1-methoxy-2-hydroxyanthraquinone, see: Ali et al. (2000 ); Jia et al. (2007 ); Wu et al. (2003 ). For related structures, see: Boonnak et al. (2005 ); Ng et al. (2005 ). For the structure of another compound isolated from Morinda officinalis How., see: Xu et al. (2009 ). For reference structural data, see: Allen et al. (1987 ).

Experimental

Crystal data

C₁₅H₁₀O₄·H₂O
M_r = 272.25
Triclinic, $[P \overline 1]$
a = 7.9583 (19) Å
b = 8.269 (2) Å
c = 10.188 (2) Å
α = 102.462 (3)°
β = 102.364 (3)°
γ = 100.653 (3)°
V = 620.4 (2) Å³
Z = 2
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 298 K
0.30 × 0.20 × 0.15 mm

Data collection

Bruker APEXII area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.973, T_max = 0.986
3218 measured reflections
2198 independent reflections
1488 reflections with I > 2σ(I)
R_int = 0.013

Refinement

R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.147
S = 1.04
2198 reflections
191 parameters
3 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.27 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H1W⋯O2ⁱ	0.86 (3)	2.31 (2)	2.960 (3)	133 (3)
O1W—H2W⋯O4ⁱⁱ	0.87 (3)	2.30 (2)	3.072 (3)	149 (3)
O3—H3⋯O1W	0.82	1.87	2.687 (2)	173
Symmetry codes: (i) x, y+1, z; (ii) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2004 ); cell refinement: 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: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809021254/bg2258sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809021254/bg2258Isup2.hkl

checkCIF report

Comment top

Anthraquinone derivatives extracted from the roots of Morinda officinalis How (most common familiar name in China: Bajitian) have been used in China since ancient times to treat a wide range of symptoms including poor digestion, high blood pressure and immune deficiencies . Recent studies have demonstrated that they have multiple pharmacological actions (Kim et al., 2005). One component found in Morinda officinalis How, 1-Methoxy-2-hydroxyanthraquinone, is known as alizarin-1-methylether and exhibits a variety of potent biological effects such as antiviral and antimicrobial activities (Ali et al., 2000), antioxidant activity (Jia et al., 2007) and cyototoxic activity (Wu et al., 2003). We report here the structure of the monhydrate.

In the title compound (Fig. 1), the C-C bond lengths show normal values (Allen et al., 1987), and the C-O and C=O bond lengths are comparable to those observed in similar structures (Ng et al., 2005; Boonnak et al., 2005). The anthraquinone ring system is substantially planar, the dihedral angle between the two benzene rings being 3.07 (4)°. In the crystal structure, the crystal water connects with alizarin-1-methylether by O—H···.O hydrogen bonds.The molecules are self-assembled by O—H···.O hydrogen bonding interactions (Table 1 and Fig. 2) into a supramolecular network.

Related literature top

For pharmacological properties of anthraquinone derivatives, see: Kim et al. (2005) and of 1-methoxy-2-hydroxyanthraquinone, see: Ali et al. (2000); Jia et al. (2007); Wu et al. (2003). For related structures, see: Boonnak et al. (2005); Ng et al. (2005). For the structure of another compound isolated from Morinda officinalis How., see: Xu et al. (2009). For bond-length data, see: Allen et al. (1987).

Experimental top

The roots of Morinda officinalis How (1000 g) were shattered to powder (about 30 mesh) and extracted with 85% ethanol (4000 ml) for 2 h with stirring. The extraction procedure was repeated three times. The extracts were combined and evaporated to dryness under reduced pressure at 333 K, the residue was redissolved in water (800 ml). Then the enriched extracts were extracted with chloroform three times (800 ml for each time), the chlorofrom solution were combined and evaporated to dryness under reduced pressure at 333 K. 6.80 g of crude extracts were obtained. The crude extracts were separated with n-hexane-ethyl acetate-methanol-water (6 : 4 : 5 : 5, v/v) using high-speed counter-current chromatography (HSCCC) to obtain 1-Methoxy-2-hydroxyanthraquinone (yield 90.6 mg). Single crystals suitable for X-ray analysis were obtained by slow evaporation of a methanol solution.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: 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: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure showing the atomic-numbering scheme and displacement ellipsoids drawn at the 30% probability level.
	Fig. 2. The molecular packing showing the hydrogen bonding interactions as broken lines.

2-Hydroxy-1-methoxyanthraquinone monohydrate top

Crystal data top

C₁₅H₁₀O₄·H₂O	Z = 2
M_r = 272.25	F(000) = 284.0
Triclinic, P1	D_x = 1.457 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.9583 (19) Å	Cell parameters from 1018 reflections
b = 8.269 (2) Å	θ = 2.6–26.2°
c = 10.188 (2) Å	µ = 0.11 mm⁻¹
α = 102.462 (3)°	T = 298 K
β = 102.364 (3)°	Block, yellow
γ = 100.653 (3)°	0.30 × 0.20 × 0.15 mm
V = 620.4 (2) Å³

Data collection top

Bruker APEXII area-detector diffractometer	2198 independent reflections
Radiation source: fine-focus sealed tube	1488 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.013
ϕ and ω scans	θ_max = 25.2°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −9→9
T_min = 0.973, T_max = 0.986	k = −9→9
3218 measured reflections	l = −12→9

Refinement top

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.147	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ²(F_o²) + (0.0778P)² + 0.0805P] where P = (F_o² + 2F_c²)/3
2198 reflections	(Δ/σ)_max < 0.001
191 parameters	Δρ_max = 0.27 e Å⁻³
3 restraints	Δρ_min = −0.17 e Å⁻³

Crystal data top

C₁₅H₁₀O₄·H₂O	γ = 100.653 (3)°
M_r = 272.25	V = 620.4 (2) Å³
Triclinic, P1	Z = 2
a = 7.9583 (19) Å	Mo Kα radiation
b = 8.269 (2) Å	µ = 0.11 mm⁻¹
c = 10.188 (2) Å	T = 298 K
α = 102.462 (3)°	0.30 × 0.20 × 0.15 mm
β = 102.364 (3)°

Data collection top

Bruker APEXII area-detector diffractometer	2198 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	1488 reflections with I > 2σ(I)
T_min = 0.973, T_max = 0.986	R_int = 0.013
3218 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	3 restraints
wR(F²) = 0.147	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	Δρ_max = 0.27 e Å⁻³
2198 reflections	Δρ_min = −0.17 e Å⁻³
191 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
C1	0.6640 (3)	0.3815 (2)	0.3121 (2)	0.0509 (5)
C2	0.7049 (3)	0.2214 (2)	0.30375 (19)	0.0476 (5)
C3	0.7720 (3)	−0.0406 (2)	0.1655 (2)	0.0485 (5)
C4	0.8497 (3)	−0.2806 (2)	0.0176 (2)	0.0555 (5)
H4	0.8772	−0.3219	0.0955	0.067*
C5	0.8632 (3)	−0.3695 (3)	−0.1086 (3)	0.0645 (6)
H5	0.8980	−0.4717	−0.1158	0.077*
C6	0.8257 (3)	−0.3093 (3)	−0.2248 (3)	0.0668 (6)
H6	0.8347	−0.3707	−0.3099	0.080*
C7	0.7746 (3)	−0.1565 (3)	−0.2142 (2)	0.0600 (6)
H7	0.7505	−0.1146	−0.2921	0.072*
C8	0.7044 (3)	0.0971 (2)	−0.07708 (19)	0.0500 (5)
C9	0.6444 (3)	0.3450 (2)	0.0710 (2)	0.0514 (5)
H9	0.6210	0.3853	−0.0078	0.062*
C10	0.6335 (3)	0.4407 (3)	0.1954 (2)	0.0542 (5)
H10	0.6054	0.5458	0.2006	0.065*
C11	0.7216 (2)	0.1254 (2)	0.17820 (19)	0.0438 (5)
C12	0.6896 (2)	0.1890 (2)	0.06001 (19)	0.0444 (5)
C13	0.7951 (2)	−0.1285 (2)	0.0293 (2)	0.0462 (5)
C14	0.7593 (2)	−0.0664 (2)	−0.08792 (19)	0.0472 (5)
C15	0.8905 (4)	0.2159 (3)	0.5181 (2)	0.0869 (8)
H15A	0.9726	0.1661	0.4763	0.130*
H15B	0.8843	0.1791	0.6005	0.130*
H15C	0.9298	0.3380	0.5425	0.130*
O1	0.6741 (2)	0.15409 (19)	−0.17812 (15)	0.0741 (5)
O2	0.7941 (3)	−0.10671 (19)	0.26171 (16)	0.0772 (5)
O3	0.6543 (2)	0.46790 (18)	0.43714 (14)	0.0679 (5)
H3	0.6315	0.5594	0.4317	0.102*
O4	0.7180 (2)	0.16259 (18)	0.42088 (14)	0.0616 (4)
O1W	0.5800 (3)	0.7728 (2)	0.44181 (19)	0.0829 (6)
H1W	0.597 (4)	0.844 (4)	0.393 (4)	0.162 (15)*
H2W	0.472 (2)	0.762 (4)	0.450 (4)	0.134 (14)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0497 (12)	0.0517 (11)	0.0508 (11)	0.0118 (9)	0.0133 (9)	0.0132 (9)
C2	0.0446 (11)	0.0537 (11)	0.0457 (11)	0.0084 (9)	0.0097 (8)	0.0211 (9)
C3	0.0464 (11)	0.0500 (11)	0.0492 (11)	0.0071 (9)	0.0100 (9)	0.0196 (9)
C4	0.0493 (12)	0.0548 (12)	0.0635 (13)	0.0132 (9)	0.0144 (10)	0.0182 (10)
C5	0.0549 (14)	0.0588 (13)	0.0799 (16)	0.0187 (10)	0.0190 (11)	0.0134 (11)
C6	0.0577 (14)	0.0715 (15)	0.0633 (14)	0.0117 (12)	0.0181 (11)	0.0030 (11)
C7	0.0561 (13)	0.0671 (14)	0.0510 (12)	0.0073 (11)	0.0120 (10)	0.0128 (10)
C8	0.0450 (11)	0.0557 (11)	0.0432 (11)	0.0020 (9)	0.0041 (8)	0.0166 (9)
C9	0.0515 (12)	0.0506 (11)	0.0516 (11)	0.0082 (9)	0.0067 (9)	0.0226 (9)
C10	0.0557 (13)	0.0504 (11)	0.0565 (12)	0.0133 (9)	0.0096 (10)	0.0191 (10)
C11	0.0370 (10)	0.0449 (10)	0.0490 (11)	0.0051 (8)	0.0090 (8)	0.0179 (8)
C12	0.0384 (10)	0.0451 (10)	0.0462 (11)	0.0028 (8)	0.0060 (8)	0.0163 (8)
C13	0.0360 (10)	0.0464 (11)	0.0533 (11)	0.0039 (8)	0.0094 (8)	0.0146 (9)
C14	0.0382 (10)	0.0504 (11)	0.0468 (11)	0.0010 (8)	0.0082 (8)	0.0115 (8)
C15	0.100 (2)	0.0976 (19)	0.0591 (15)	0.0295 (16)	−0.0015 (14)	0.0303 (14)
O1	0.1049 (13)	0.0732 (10)	0.0481 (9)	0.0260 (9)	0.0141 (8)	0.0263 (7)
O2	0.1226 (15)	0.0696 (10)	0.0615 (10)	0.0433 (10)	0.0352 (9)	0.0355 (8)
O3	0.0926 (12)	0.0649 (10)	0.0561 (9)	0.0349 (9)	0.0257 (8)	0.0172 (7)
O4	0.0760 (10)	0.0684 (9)	0.0503 (8)	0.0229 (8)	0.0207 (7)	0.0277 (7)
O1W	0.1221 (18)	0.0768 (12)	0.0776 (12)	0.0454 (11)	0.0478 (11)	0.0384 (10)

Geometric parameters (Å, º) top

C1—O3	1.345 (2)	C8—O1	1.218 (2)
C1—C10	1.373 (3)	C8—C12	1.479 (3)
C1—C2	1.410 (3)	C8—C14	1.486 (3)
C2—O4	1.374 (2)	C9—C10	1.371 (3)
C2—C11	1.399 (3)	C9—C12	1.390 (3)
C3—O2	1.218 (2)	C9—H9	0.9300
C3—C13	1.487 (3)	C10—H10	0.9300
C3—C11	1.487 (3)	C11—C12	1.408 (2)
C4—C5	1.373 (3)	C13—C14	1.395 (3)
C4—C13	1.394 (3)	C15—O4	1.437 (3)
C4—H4	0.9300	C15—H15A	0.9600
C5—C6	1.377 (3)	C15—H15B	0.9600
C5—H5	0.9300	C15—H15C	0.9600
C6—C7	1.387 (3)	O3—H3	0.8200
C6—H6	0.9300	O1W—H1W	0.86 (3)
C7—C14	1.382 (3)	O1W—H2W	0.87 (3)
C7—H7	0.9300

O3—C1—C10	123.24 (18)	C12—C9—H9	119.2
O3—C1—C2	116.77 (17)	C9—C10—C1	120.01 (18)
C10—C1—C2	119.98 (18)	C9—C10—H10	120.0
O4—C2—C11	122.55 (17)	C1—C10—H10	120.0
O4—C2—C1	117.08 (17)	C2—C11—C12	118.56 (17)
C11—C2—C1	120.29 (16)	C2—C11—C3	122.38 (16)
O2—C3—C13	119.21 (18)	C12—C11—C3	119.06 (17)
O2—C3—C11	122.56 (18)	C9—C12—C11	119.58 (18)
C13—C3—C11	118.22 (16)	C9—C12—C8	117.85 (17)
C5—C4—C13	120.20 (19)	C11—C12—C8	122.57 (17)
C5—C4—H4	119.9	C4—C13—C14	118.95 (18)
C13—C4—H4	119.9	C4—C13—C3	118.85 (17)
C4—C5—C6	120.9 (2)	C14—C13—C3	122.18 (17)
C4—C5—H5	119.6	C7—C14—C13	120.27 (19)
C6—C5—H5	119.6	C7—C14—C8	119.88 (18)
C5—C6—C7	119.6 (2)	C13—C14—C8	119.85 (18)
C5—C6—H6	120.2	O4—C15—H15A	109.5
C7—C6—H6	120.2	O4—C15—H15B	109.5
C14—C7—C6	120.1 (2)	H15A—C15—H15B	109.5
C14—C7—H7	120.0	O4—C15—H15C	109.5
C6—C7—H7	119.9	H15A—C15—H15C	109.5
O1—C8—C12	121.26 (19)	H15B—C15—H15C	109.5
O1—C8—C14	120.74 (18)	C1—O3—H3	109.5
C12—C8—C14	117.99 (16)	C2—O4—C15	115.30 (16)
C10—C9—C12	121.52 (18)	H1W—O1W—H2W	107.3 (16)
C10—C9—H9	119.2

O3—C1—C2—O4	4.7 (3)	C3—C11—C12—C8	−0.1 (3)
C10—C1—C2—O4	−174.23 (17)	O1—C8—C12—C9	−1.6 (3)
O3—C1—C2—C11	−178.49 (17)	C14—C8—C12—C9	177.72 (16)
C10—C1—C2—C11	2.6 (3)	O1—C8—C12—C11	179.19 (17)
C13—C4—C5—C6	1.0 (3)	C14—C8—C12—C11	−1.5 (3)
C4—C5—C6—C7	0.3 (3)	C5—C4—C13—C14	−1.7 (3)
C5—C6—C7—C14	−0.7 (3)	C5—C4—C13—C3	176.53 (17)
C12—C9—C10—C1	−1.3 (3)	O2—C3—C13—C4	−3.0 (3)
O3—C1—C10—C9	−179.48 (18)	C11—C3—C13—C4	177.29 (16)
C2—C1—C10—C9	−0.6 (3)	O2—C3—C13—C14	175.24 (18)
O4—C2—C11—C12	174.08 (16)	C11—C3—C13—C14	−4.5 (3)
C1—C2—C11—C12	−2.5 (3)	C6—C7—C14—C13	−0.1 (3)
O4—C2—C11—C3	−6.0 (3)	C6—C7—C14—C8	−179.97 (18)
C1—C2—C11—C3	177.34 (16)	C4—C13—C14—C7	1.3 (3)
O2—C3—C11—C2	3.3 (3)	C3—C13—C14—C7	−176.93 (17)
C13—C3—C11—C2	−176.94 (16)	C4—C13—C14—C8	−178.80 (17)
O2—C3—C11—C12	−176.78 (18)	C3—C13—C14—C8	3.0 (3)
C13—C3—C11—C12	2.9 (3)	O1—C8—C14—C7	−0.7 (3)
C10—C9—C12—C11	1.3 (3)	C12—C8—C14—C7	179.92 (16)
C10—C9—C12—C8	−177.90 (17)	O1—C8—C14—C13	179.34 (18)
C2—C11—C12—C9	0.6 (3)	C12—C8—C14—C13	0.0 (3)
C3—C11—C12—C9	−179.25 (16)	C11—C2—O4—C15	95.3 (2)
C2—C11—C12—C8	179.82 (16)	C1—C2—O4—C15	−87.9 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1W···O2ⁱ	0.86 (3)	2.31 (2)	2.960 (3)	133 (3)
O1W—H2W···O4ⁱⁱ	0.87 (3)	2.30 (2)	3.072 (3)	149 (3)
O3—H3···O1W	0.82	1.87	2.687 (2)	173

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

Experimental details

Crystal data
Chemical formula	C₁₅H₁₀O₄·H₂O
M_r	272.25
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	7.9583 (19), 8.269 (2), 10.188 (2)
α, β, γ (°)	102.462 (3), 102.364 (3), 100.653 (3)
V (Å³)	620.4 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.30 × 0.20 × 0.15

Data collection
Diffractometer	Bruker APEXII area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.973, 0.986
No. of measured, independent and observed [I > 2σ(I)] reflections	3218, 2198, 1488
R_int	0.013
(sin θ/λ)_max (Å⁻¹)	0.599

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.147, 1.04
No. of reflections	2198
No. of parameters	191
No. of restraints	3
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.27, −0.17

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1W···O2ⁱ	0.86 (3)	2.31 (2)	2.960 (3)	133 (3)
O1W—H2W···O4ⁱⁱ	0.87 (3)	2.30 (2)	3.072 (3)	149 (3)
O3—H3···O1W	0.82	1.87	2.687 (2)	173.2

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

Acknowledgements

The authors acknowledge South China University of Technology and Dongguan University of Technology for support of this work.

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