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ISSN: 2056-9890

2-Hydr­­oxy-1-meth­oxy­anthra­quinone monohydrate

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[Kim, I. T., Park, H. J., Nam, J. H., Park, Y. M., Won, J. H., Choi, J., Choe, B. K. & Lee, K. T. (2005). J. Pharm. Pharmacol. 57, 607-615.]) and of 1-meth­oxy-2-hydroxy­anthraquinone, see: Ali et al. (2000[Ali, A. M., Ismail, N. H., Mackeen, M. M., Yazan, L. S., Mohamed, S. M., Ho, A. S. H. & Lajis, N. H. (2000). Pharm. Biol. 38, 298-301.]); Jia et al. (2007[Jia, Z. B., Tao, F., Guo, L., Tao, G. L. & Ding, X. L. (2007). LWT Food Sci. Technol. 40, 1072-1077.]); Wu et al. (2003[Wu, T. S., Lin, D. M., Shi, L. S., Damu, A. G., Kuo, P. C. & Kuo, Y. H. (2003). Chem. Pharm. Bull. 51, 948-950.]). For related structures, see: Boonnak et al. (2005[Boonnak, N., Chantrapromma, S., Fun, H.-K., Anjum, S., Ali, S., Atta-ur-Rahman & Karalai, C. (2005). Acta Cryst. E61, o410-o412.]); Ng et al. (2005[Ng, S.-L., Razak, I. A., Fun, H.-K., Boonsri, S., Chantrapromma, S. & Prawat, U. (2005). Acta Cryst. E61, o3656-o3658.]). For the structure of another compound isolated from Morinda officinalis How., see: Xu et al. (2009[Xu, Y.-J., Yang, X.-X. & Zhao, H.-B. (2009). Acta Cryst. E65, o1524.]). For reference structural data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Jin, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C15H10O4·H2O

  • Mr = 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[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.973, Tmax = 0.986

  • 3218 measured reflections

  • 2198 independent reflections

  • 1488 reflections with I > 2σ(I)

  • Rint = 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

  • Δρmax = 0.27 e Å−3

  • Δρmin = −0.17 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA 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[Bruker (2004). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2004[Bruker (2004). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXL97.

Supporting information


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.

Refinement top

H atoms not pertaining to water molecules were placed at calculated positions and treated as riding on the parent atoms with C—H = 0.93–0.97 and O—H = 0.82 Å, and with Uiso(H) = 1.2 or 1.5 Ueq(C, O). The water hydrogen atoms were found from the Fourier maps and refined with restrained O-H=0.86 (3)Å and free Uiso(H).

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
[Figure 1] Fig. 1. The molecular structure showing the atomic-numbering scheme and displacement ellipsoids drawn at the 30% probability level.
[Figure 2] Fig. 2. The molecular packing showing the hydrogen bonding interactions as broken lines.
2-Hydroxy-1-methoxyanthraquinone monohydrate top
Crystal data top
C15H10O4·H2OZ = 2
Mr = 272.25F(000) = 284.0
Triclinic, P1Dx = 1.457 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.9583 (19) ÅCell parameters from 1018 reflections
b = 8.269 (2) Åθ = 2.6–26.2°
c = 10.188 (2) ŵ = 0.11 mm1
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 tube1488 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.013
ϕ and ω scansθmax = 25.2°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 99
Tmin = 0.973, Tmax = 0.986k = 99
3218 measured reflectionsl = 129
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)] = 0.046Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.147H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.0778P)2 + 0.0805P]
where P = (Fo2 + 2Fc2)/3
2198 reflections(Δ/σ)max < 0.001
191 parametersΔρmax = 0.27 e Å3
3 restraintsΔρmin = 0.17 e Å3
Crystal data top
C15H10O4·H2Oγ = 100.653 (3)°
Mr = 272.25V = 620.4 (2) Å3
Triclinic, P1Z = 2
a = 7.9583 (19) ÅMo Kα radiation
b = 8.269 (2) ŵ = 0.11 mm1
c = 10.188 (2) ÅT = 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)
Tmin = 0.973, Tmax = 0.986Rint = 0.013
3218 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0463 restraints
wR(F2) = 0.147H atoms treated by a mixture of independent and constrained refinement
S = 1.04Δρmax = 0.27 e Å3
2198 reflectionsΔρmin = 0.17 e Å3
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
xyzUiso*/Ueq
C10.6640 (3)0.3815 (2)0.3121 (2)0.0509 (5)
C20.7049 (3)0.2214 (2)0.30375 (19)0.0476 (5)
C30.7720 (3)0.0406 (2)0.1655 (2)0.0485 (5)
C40.8497 (3)0.2806 (2)0.0176 (2)0.0555 (5)
H40.87720.32190.09550.067*
C50.8632 (3)0.3695 (3)0.1086 (3)0.0645 (6)
H50.89800.47170.11580.077*
C60.8257 (3)0.3093 (3)0.2248 (3)0.0668 (6)
H60.83470.37070.30990.080*
C70.7746 (3)0.1565 (3)0.2142 (2)0.0600 (6)
H70.75050.11460.29210.072*
C80.7044 (3)0.0971 (2)0.07708 (19)0.0500 (5)
C90.6444 (3)0.3450 (2)0.0710 (2)0.0514 (5)
H90.62100.38530.00780.062*
C100.6335 (3)0.4407 (3)0.1954 (2)0.0542 (5)
H100.60540.54580.20060.065*
C110.7216 (2)0.1254 (2)0.17820 (19)0.0438 (5)
C120.6896 (2)0.1890 (2)0.06001 (19)0.0444 (5)
C130.7951 (2)0.1285 (2)0.0293 (2)0.0462 (5)
C140.7593 (2)0.0664 (2)0.08792 (19)0.0472 (5)
C150.8905 (4)0.2159 (3)0.5181 (2)0.0869 (8)
H15A0.97260.16610.47630.130*
H15B0.88430.17910.60050.130*
H15C0.92980.33800.54250.130*
O10.6741 (2)0.15409 (19)0.17812 (15)0.0741 (5)
O20.7941 (3)0.10671 (19)0.26171 (16)0.0772 (5)
O30.6543 (2)0.46790 (18)0.43714 (14)0.0679 (5)
H30.63150.55940.43170.102*
O40.7180 (2)0.16259 (18)0.42088 (14)0.0616 (4)
O1W0.5800 (3)0.7728 (2)0.44181 (19)0.0829 (6)
H1W0.597 (4)0.844 (4)0.393 (4)0.162 (15)*
H2W0.472 (2)0.762 (4)0.450 (4)0.134 (14)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0497 (12)0.0517 (11)0.0508 (11)0.0118 (9)0.0133 (9)0.0132 (9)
C20.0446 (11)0.0537 (11)0.0457 (11)0.0084 (9)0.0097 (8)0.0211 (9)
C30.0464 (11)0.0500 (11)0.0492 (11)0.0071 (9)0.0100 (9)0.0196 (9)
C40.0493 (12)0.0548 (12)0.0635 (13)0.0132 (9)0.0144 (10)0.0182 (10)
C50.0549 (14)0.0588 (13)0.0799 (16)0.0187 (10)0.0190 (11)0.0134 (11)
C60.0577 (14)0.0715 (15)0.0633 (14)0.0117 (12)0.0181 (11)0.0030 (11)
C70.0561 (13)0.0671 (14)0.0510 (12)0.0073 (11)0.0120 (10)0.0128 (10)
C80.0450 (11)0.0557 (11)0.0432 (11)0.0020 (9)0.0041 (8)0.0166 (9)
C90.0515 (12)0.0506 (11)0.0516 (11)0.0082 (9)0.0067 (9)0.0226 (9)
C100.0557 (13)0.0504 (11)0.0565 (12)0.0133 (9)0.0096 (10)0.0191 (10)
C110.0370 (10)0.0449 (10)0.0490 (11)0.0051 (8)0.0090 (8)0.0179 (8)
C120.0384 (10)0.0451 (10)0.0462 (11)0.0028 (8)0.0060 (8)0.0163 (8)
C130.0360 (10)0.0464 (11)0.0533 (11)0.0039 (8)0.0094 (8)0.0146 (9)
C140.0382 (10)0.0504 (11)0.0468 (11)0.0010 (8)0.0082 (8)0.0115 (8)
C150.100 (2)0.0976 (19)0.0591 (15)0.0295 (16)0.0015 (14)0.0303 (14)
O10.1049 (13)0.0732 (10)0.0481 (9)0.0260 (9)0.0141 (8)0.0263 (7)
O20.1226 (15)0.0696 (10)0.0615 (10)0.0433 (10)0.0352 (9)0.0355 (8)
O30.0926 (12)0.0649 (10)0.0561 (9)0.0349 (9)0.0257 (8)0.0172 (7)
O40.0760 (10)0.0684 (9)0.0503 (8)0.0229 (8)0.0207 (7)0.0277 (7)
O1W0.1221 (18)0.0768 (12)0.0776 (12)0.0454 (11)0.0478 (11)0.0384 (10)
Geometric parameters (Å, º) top
C1—O31.345 (2)C8—O11.218 (2)
C1—C101.373 (3)C8—C121.479 (3)
C1—C21.410 (3)C8—C141.486 (3)
C2—O41.374 (2)C9—C101.371 (3)
C2—C111.399 (3)C9—C121.390 (3)
C3—O21.218 (2)C9—H90.9300
C3—C131.487 (3)C10—H100.9300
C3—C111.487 (3)C11—C121.408 (2)
C4—C51.373 (3)C13—C141.395 (3)
C4—C131.394 (3)C15—O41.437 (3)
C4—H40.9300C15—H15A0.9600
C5—C61.377 (3)C15—H15B0.9600
C5—H50.9300C15—H15C0.9600
C6—C71.387 (3)O3—H30.8200
C6—H60.9300O1W—H1W0.86 (3)
C7—C141.382 (3)O1W—H2W0.87 (3)
C7—H70.9300
O3—C1—C10123.24 (18)C12—C9—H9119.2
O3—C1—C2116.77 (17)C9—C10—C1120.01 (18)
C10—C1—C2119.98 (18)C9—C10—H10120.0
O4—C2—C11122.55 (17)C1—C10—H10120.0
O4—C2—C1117.08 (17)C2—C11—C12118.56 (17)
C11—C2—C1120.29 (16)C2—C11—C3122.38 (16)
O2—C3—C13119.21 (18)C12—C11—C3119.06 (17)
O2—C3—C11122.56 (18)C9—C12—C11119.58 (18)
C13—C3—C11118.22 (16)C9—C12—C8117.85 (17)
C5—C4—C13120.20 (19)C11—C12—C8122.57 (17)
C5—C4—H4119.9C4—C13—C14118.95 (18)
C13—C4—H4119.9C4—C13—C3118.85 (17)
C4—C5—C6120.9 (2)C14—C13—C3122.18 (17)
C4—C5—H5119.6C7—C14—C13120.27 (19)
C6—C5—H5119.6C7—C14—C8119.88 (18)
C5—C6—C7119.6 (2)C13—C14—C8119.85 (18)
C5—C6—H6120.2O4—C15—H15A109.5
C7—C6—H6120.2O4—C15—H15B109.5
C14—C7—C6120.1 (2)H15A—C15—H15B109.5
C14—C7—H7120.0O4—C15—H15C109.5
C6—C7—H7119.9H15A—C15—H15C109.5
O1—C8—C12121.26 (19)H15B—C15—H15C109.5
O1—C8—C14120.74 (18)C1—O3—H3109.5
C12—C8—C14117.99 (16)C2—O4—C15115.30 (16)
C10—C9—C12121.52 (18)H1W—O1W—H2W107.3 (16)
C10—C9—H9119.2
O3—C1—C2—O44.7 (3)C3—C11—C12—C80.1 (3)
C10—C1—C2—O4174.23 (17)O1—C8—C12—C91.6 (3)
O3—C1—C2—C11178.49 (17)C14—C8—C12—C9177.72 (16)
C10—C1—C2—C112.6 (3)O1—C8—C12—C11179.19 (17)
C13—C4—C5—C61.0 (3)C14—C8—C12—C111.5 (3)
C4—C5—C6—C70.3 (3)C5—C4—C13—C141.7 (3)
C5—C6—C7—C140.7 (3)C5—C4—C13—C3176.53 (17)
C12—C9—C10—C11.3 (3)O2—C3—C13—C43.0 (3)
O3—C1—C10—C9179.48 (18)C11—C3—C13—C4177.29 (16)
C2—C1—C10—C90.6 (3)O2—C3—C13—C14175.24 (18)
O4—C2—C11—C12174.08 (16)C11—C3—C13—C144.5 (3)
C1—C2—C11—C122.5 (3)C6—C7—C14—C130.1 (3)
O4—C2—C11—C36.0 (3)C6—C7—C14—C8179.97 (18)
C1—C2—C11—C3177.34 (16)C4—C13—C14—C71.3 (3)
O2—C3—C11—C23.3 (3)C3—C13—C14—C7176.93 (17)
C13—C3—C11—C2176.94 (16)C4—C13—C14—C8178.80 (17)
O2—C3—C11—C12176.78 (18)C3—C13—C14—C83.0 (3)
C13—C3—C11—C122.9 (3)O1—C8—C14—C70.7 (3)
C10—C9—C12—C111.3 (3)C12—C8—C14—C7179.92 (16)
C10—C9—C12—C8177.90 (17)O1—C8—C14—C13179.34 (18)
C2—C11—C12—C90.6 (3)C12—C8—C14—C130.0 (3)
C3—C11—C12—C9179.25 (16)C11—C2—O4—C1595.3 (2)
C2—C11—C12—C8179.82 (16)C1—C2—O4—C1587.9 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1W···O2i0.86 (3)2.31 (2)2.960 (3)133 (3)
O1W—H2W···O4ii0.87 (3)2.30 (2)3.072 (3)149 (3)
O3—H3···O1W0.821.872.687 (2)173
Symmetry codes: (i) x, y+1, z; (ii) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC15H10O4·H2O
Mr272.25
Crystal system, space groupTriclinic, 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)
V3)620.4 (2)
Z2
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.30 × 0.20 × 0.15
Data collection
DiffractometerBruker APEXII area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.973, 0.986
No. of measured, independent and
observed [I > 2σ(I)] reflections
3218, 2198, 1488
Rint0.013
(sin θ/λ)max1)0.599
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.046, 0.147, 1.04
No. of reflections2198
No. of parameters191
No. of restraints3
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)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···AD—HH···AD···AD—H···A
O1W—H1W···O2i0.86 (3)2.31 (2)2.960 (3)133 (3)
O1W—H2W···O4ii0.87 (3)2.30 (2)3.072 (3)149 (3)
O3—H3···O1W0.821.872.687 (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.

References

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