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Acta Crystallogr Sect E Struct Rep Online. 2009 September 1; 65(Pt 9): o2176.
Published online 2009 August 19. doi:  10.1107/S1600536809031614
PMCID: PMC2969919

Methyl 5-chloro-2-hydr­oxy-3-(4-methoxy­phen­yl)-4,6-dimethyl­benzoate

Abstract

In the title compound, C17H17ClO4, the dihedral angle between the mean planes of the two benzene rings is 65.92 (5)°. The methyl ester group lies within the ring plane [deviations of O atoms from the plane = −0.051 (2) and 0.151 (2) Å] due to an intra­molecular O—H(...)O hydrogen bond. In the crystal, mol­ecules are held together by rather weak non-classical inter­molecular C—H(...)O hydrogen bonds, resulting in dimeric units about inversion centers, forming eight- and ten-membered ring systems as R 2 2(8) and R 2 2(10) motifs.

Related literature

For the pharmacological relevance of 3-aryl­salicylates, see: Buchanan et al. (1997 [triangle]); Huang et al. (1999 [triangle]); Lin, Lin & Kuo (1997 [triangle]); Lin, Wu & Kuo (1997 [triangle]). For the synthesis, see: Adeel et al. (2009 [triangle]); For hydrogen-bond motifs, see: Bernstein et al. (1994 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-o2176-scheme1.jpg

Experimental

Crystal data

  • C17H17ClO4
  • M r = 320.76
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o2176-efi1.jpg
  • a = 6.534 (4) Å
  • b = 9.574 (6) Å
  • c = 12.694 (8) Å
  • α = 97.420 (15)°
  • β = 100.56 (2)°
  • γ = 96.042 (14)°
  • V = 767.3 (8) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.26 mm−1
  • T = 173 K
  • 0.55 × 0.27 × 0.01 mm

Data collection

  • Bruker APEXII CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 2004 [triangle]) T min = 0.868, T max = 0.997
  • 14947 measured reflections
  • 3964 independent reflections
  • 3091 reflections with I > 2σ(I)
  • R int = 0.024

Refinement

  • R[F 2 > 2σ(F 2)] = 0.040
  • wR(F 2) = 0.125
  • S = 1.09
  • 3964 reflections
  • 207 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.31 e Å−3
  • Δρmin = −0.23 e Å−3

Data collection: APEX2 (Bruker, 2003 [triangle]); cell refinement: SAINT (Bruker, 2003 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]) and DIAMOND (Brandenburg, 2005 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809031614/pv2189sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809031614/pv2189Isup2.hkl

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

Acknowledgments

Financial support for MA from the Higher Education Commission of Pakistan (HEC) under the IPFP programe is gratefully acknowledged.

supplementary crystallographic information

Comment

Functionalized biaryls containing a 3-arylsalicylate substructure occur in a variety of pharmacologically relevant natural products. The simple biaryls cynandione A—C have been isolated from many plant sources and show a considerable in vitro activity against hepatocytes, human bladder carcinoma T-24 cells, epidermoid carcinoma KB cells, and human hepatoma PLC/PRF/5 cells. For data on the pharmacological relevance of 3-arylsalicylates, see: Buchanan et al., (1997), Huang et al., (1999), Lin, Lin & Kuo (1997) and Lin, Wu & Kuo (1997). The sterically encumbered and functionalized biaryl, the title compound (I), was synthesized from 4-(4-methoxyphenyl)-1,3-bis(trimethylsilyloxy)-1,3-butadiene which is not readily available by other methods. In this paper, the crystal structure of (I) has been presented.

In the title compound (Fig. 1), the the dihedral angle between the mean planes of the two benzene rings is 65.92 (5)°. The methoxy group and the methylester group lie within the planes of the benzene rings to which they are bonded (deviation from mean planes: O2, -0.051 (2); O3, 0.151 (2); (??), 0.143 (2) Å; the torsion angles are: C2—C3—C8—O2 -174.47 (12) and C17—O4—C14—C15 -176.38 (12)°). There is an intramolecular hydrogen bond between the hydroxyl group and the carbonyl O atom of the methylester group. There are weak intramolecular interactions of the types C—H···O between atom O3 of the ester group and the adjacent methyl group (C10) and C—H···Cl between Cl1 and the adjacent methyl groups (C7/C10).

In the crystal structure, the molecules of (I) are held together by rather weak intermolecular C—H···O type non-classical hydrogen bonds resulting in dimeric units about inversion centers, forming eight and ten membered ring systems which may be described in terms of graph set notations (Bernstein et al. 1994) as R22(8) and R22(10) motifs for the hydrogen bonds: C15–H15···O4ii and C9–H9A···O2i, respectively (details are given in Table 1 and Figure 2); leading to a zigzag chain arrangement.

Experimental

The title compound was prepared according to a previously published procedure (Adeel et al., 2009) using 3-chloro-4-trimethylsiloxy-pent-3-en-2-one (450 mg, 2.2 mmol), 4-(4-methoxyphenyl)-1,3-bis(silyloxy)-1,3-diene (806 mg, 2.2 mmol), and TiCl4 (0.241 ml, 2.2 mmol). (I) was isolated as a colourless crystalline solid. Re-crystallization from a saturated dichloromethane/methanol (9:1) solution at ambient temperature gave colourless crystals suitable for crystallographic studies.

Refinement

The H atom bonded to O1 was located in a difference map and refined freely. Other H atoms were positioned geometrically and refined using a riding model, with C—H = 0.98 (methyl groups) or 0.95 Å (aryl CH) and with Uiso(H) = 1.5 times Ueq(C) (methyl groups) or with Uiso(H) = 1.2 times Ueq(C) (aryl CH). Torsion angles of all methyl groups were allowed to refine.

Figures

Fig. 1.
Molecular structure of (I), showing the atomic numbering scheme and displacement ellipsoids drawn at the 50% probability level.
Fig. 2.
Part of the packing diagram of (I). Unique O—H···O, C—H···O and C—H···Cl interactions represented by dashed lines are shown.

Crystal data

C17H17ClO4Z = 2
Mr = 320.76F(000) = 336
Triclinic, P1Dx = 1.388 Mg m3
Hall symbol: -P 1Melting point: 367 K
a = 6.534 (4) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.574 (6) ÅCell parameters from 7750 reflections
c = 12.694 (8) Åθ = 6.4–59.5°
α = 97.420 (15)°µ = 0.26 mm1
β = 100.56 (2)°T = 173 K
γ = 96.042 (14)°Plate, colourless
V = 767.3 (8) Å30.55 × 0.27 × 0.01 mm

Data collection

Bruker APEXII CCD diffractometer3964 independent reflections
Radiation source: sealed tube3091 reflections with I > 2σ(I)
graphiteRint = 0.024
ω scansθmax = 29.0°, θmin = 4.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)h = −8→8
Tmin = 0.868, Tmax = 0.997k = −13→13
14947 measured reflectionsl = −17→17

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.125H atoms treated by a mixture of independent and constrained refinement
S = 1.09w = 1/[σ2(Fo2) + (0.073P)2 + 0.0592P] where P = (Fo2 + 2Fc2)/3
3964 reflections(Δ/σ)max < 0.001
207 parametersΔρmax = 0.31 e Å3
0 restraintsΔρmin = −0.23 e Å3

Special details

Experimental. Yield: 241 mg, 38%. m.p. = 367 (2) K. 1H NMR (250 MHz, CDCl3): δ = 2.10 (s, 3H, CH3), 2.56 (s, 3H, CH3), 3.77 (s, 3H, OCH3), 3.89 (s, 3H, OCH3), 6.89 (d, 2H, J = 8.8 Hz, ArH), 7.03 (d, 2H, J = 8.8 Hz, ArH), 10.54 (s, 1 H, OH). 13C NMR (62 MHz, CDCl3): δ = 19.0, 19.4 (CH3), 51.4, 54.2 (OCH3), 111.5 (C), 112.9 (2 C, CH), 126.8, 127.6, 128.3 (C), 129.9 (2 C, CH), 135.3, 140.8, 156.1, 157.8 (C), 170.5 (C=O). IR (KBr, cm -1): ~ν = 3430 (m), 3050 (w), 3002 (w), 2959 (m), 2931 (m), 2837 (m), 1653 (s), 1607 (m), 1572 (w), 1514 (s), 1444 (s), 1373 (m), 1361 (s), 1297 (s), 1253 (s), 1220 (s), 1176 (m), 1092 (m), 1036 (m) 810 (m), 686 (m). GC—MS (EI, 70 eV): m/z (%): 322 (M+, 37Cl, 16), 320 (M+, 47), 288 (100), 260 (11), 245 (27), 225 (29), 181 (7), 152 (12). HRMS (EI, 70 eV): calcd for C17H17O4Cl [M, 35Cl]: 320.08099; found 320.08088.
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes.Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)- 3.7416 (0.0035) x + 4.8249 (0.0051) y - 7.9961 (0.0069) z = 2.4746 (0.0052)* 0.0019 (0.0009) C1 * -0.0098 (0.0009) C2 * 0.0101 (0.0008) C3 * -0.0023 (0.0008) C4 * -0.0059 (0.0008) C5 * 0.0061 (0.0008) C6 0.0307 (0.0018) C8 - 0.0505 (0.0021) O2 0.1508 (0.0021) O3 0.1865 (0.0030) C9Rms deviation of fitted atoms = 0.00683.1094 (0.0040) x + 6.1432 (0.0055) y - 9.0638 (0.0075) z = 4.7524 (0.0041)Angle to previous plane (with approximate su) = 65.92 (0.05)* 0.0117 (0.0009) C11 * -0.0089 (0.0009) C12 * -0.0016 (0.0009) C13 * 0.0091 (0.0009) C14 * -0.0060 (0.0010) C15 * -0.0043 (0.0010) C16 0.0476 (0.0018) O4 0.1434 (0.0024) C17Rms deviation of fitted atoms = 0.0077
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 > 2σ(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)

xyzUiso*/Ueq
O1−0.09153 (15)0.87698 (10)0.26779 (8)0.0377 (2)
H1−0.175 (3)0.892 (2)0.3196 (17)0.067 (6)*
O2−0.25708 (18)0.99014 (12)0.41459 (9)0.0505 (3)
O3−0.16796 (18)1.21628 (12)0.48417 (9)0.0491 (3)
O40.23627 (16)0.52864 (10)−0.09022 (8)0.0405 (2)
Cl10.48249 (6)1.39934 (4)0.30599 (3)0.05110 (15)
C10.3067 (2)1.24545 (14)0.29830 (10)0.0313 (3)
C20.1636 (2)1.24546 (14)0.36668 (10)0.0310 (3)
C30.02086 (19)1.11978 (13)0.35519 (9)0.0279 (3)
C40.03415 (19)1.00141 (13)0.27908 (10)0.0272 (3)
C50.18323 (18)1.00544 (13)0.21221 (9)0.0265 (3)
C60.32076 (19)1.12961 (13)0.22127 (9)0.0282 (3)
C70.4785 (2)1.14192 (16)0.14895 (11)0.0386 (3)
H7A0.45381.05720.09370.058*
H7B0.62071.15010.19250.058*
H7C0.46371.22650.11360.058*
C8−0.1451 (2)1.10217 (14)0.41965 (10)0.0318 (3)
C9−0.3311 (3)1.20118 (19)0.54694 (14)0.0515 (4)
H9A−0.46731.17100.49780.077*
H9B−0.33461.29250.59100.077*
H9C−0.30181.12980.59450.077*
C100.1683 (3)1.37309 (18)0.45028 (13)0.0513 (4)
H10A0.29951.43670.45760.077*
H10B0.15991.34210.52020.077*
H10C0.04871.42350.42750.077*
C110.18957 (19)0.87662 (13)0.13357 (9)0.0277 (3)
C120.0254 (2)0.82784 (14)0.04645 (10)0.0310 (3)
H12−0.09620.87500.03890.037*
C130.0333 (2)0.71183 (14)−0.03026 (10)0.0320 (3)
H13−0.08050.6811−0.08990.038*
C140.2094 (2)0.64160 (13)−0.01864 (10)0.0312 (3)
C150.3732 (2)0.68633 (15)0.06955 (11)0.0366 (3)
H150.49270.63720.07850.044*
C160.3628 (2)0.80242 (15)0.14448 (11)0.0348 (3)
H160.47600.83220.20460.042*
C170.0787 (3)0.48428 (16)−0.18492 (11)0.0427 (3)
H17A−0.05370.4516−0.16440.064*
H17B0.12130.4064−0.23060.064*
H17C0.05960.5642−0.22520.064*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0325 (5)0.0332 (5)0.0465 (5)−0.0037 (4)0.0149 (4)−0.0005 (4)
O20.0459 (6)0.0494 (7)0.0592 (7)−0.0045 (5)0.0307 (5)−0.0012 (5)
O30.0522 (7)0.0473 (6)0.0545 (6)0.0061 (5)0.0337 (5)−0.0003 (5)
O40.0479 (6)0.0350 (5)0.0402 (5)0.0133 (4)0.0143 (4)−0.0022 (4)
Cl10.0526 (3)0.0427 (2)0.0526 (2)−0.01755 (17)0.02060 (18)−0.00782 (16)
C10.0298 (6)0.0316 (7)0.0294 (6)−0.0037 (5)0.0050 (5)0.0013 (5)
C20.0305 (7)0.0336 (7)0.0270 (6)0.0029 (5)0.0054 (5)−0.0007 (5)
C30.0247 (6)0.0327 (6)0.0268 (6)0.0058 (5)0.0056 (5)0.0045 (5)
C40.0221 (6)0.0296 (6)0.0289 (6)0.0029 (5)0.0032 (4)0.0039 (4)
C50.0236 (6)0.0299 (6)0.0256 (5)0.0056 (5)0.0030 (4)0.0034 (4)
C60.0246 (6)0.0345 (7)0.0246 (5)0.0022 (5)0.0042 (4)0.0040 (5)
C70.0358 (7)0.0452 (8)0.0354 (7)−0.0010 (6)0.0149 (6)0.0024 (6)
C80.0274 (6)0.0408 (7)0.0293 (6)0.0080 (6)0.0074 (5)0.0075 (5)
C90.0509 (9)0.0617 (11)0.0531 (9)0.0171 (8)0.0336 (8)0.0092 (7)
C100.0572 (10)0.0446 (9)0.0485 (8)−0.0076 (7)0.0249 (7)−0.0150 (7)
C110.0268 (6)0.0287 (6)0.0282 (6)0.0045 (5)0.0072 (5)0.0032 (5)
C120.0291 (6)0.0308 (6)0.0325 (6)0.0086 (5)0.0040 (5)0.0023 (5)
C130.0337 (7)0.0318 (7)0.0292 (6)0.0058 (5)0.0038 (5)0.0016 (5)
C140.0370 (7)0.0267 (6)0.0336 (6)0.0071 (5)0.0152 (5)0.0046 (5)
C150.0317 (7)0.0418 (8)0.0401 (7)0.0154 (6)0.0108 (6)0.0061 (6)
C160.0274 (7)0.0412 (8)0.0348 (6)0.0082 (6)0.0038 (5)0.0027 (5)
C170.0569 (9)0.0345 (7)0.0368 (7)0.0054 (6)0.0154 (6)−0.0030 (5)

Geometric parameters (Å, °)

O1—C41.3495 (17)C7—H7C0.9800
O1—H10.94 (2)C9—H9A0.9800
O2—C81.2205 (18)C9—H9B0.9800
O3—C81.3170 (18)C9—H9C0.9800
O3—C91.4496 (19)C10—H10A0.9800
O4—C141.3678 (16)C10—H10B0.9800
O4—C171.4169 (19)C10—H10C0.9800
Cl1—C11.7510 (16)C11—C121.3850 (18)
C1—C21.3870 (19)C11—C161.3937 (19)
C1—C61.4033 (18)C12—C131.3914 (18)
C2—C31.417 (2)C12—H120.9500
C2—C101.505 (2)C13—C141.3869 (19)
C3—C41.4121 (18)C13—H130.9500
C3—C81.4821 (19)C14—C151.387 (2)
C4—C51.4052 (18)C15—C161.382 (2)
C5—C61.3913 (19)C15—H150.9500
C5—C111.4925 (18)C16—H160.9500
C6—C71.5061 (19)C17—H17A0.9800
C7—H7A0.9800C17—H17B0.9800
C7—H7B0.9800C17—H17C0.9800
C4—O1—H1104.4 (13)O3—C9—H9C109.5
C8—O3—C9116.73 (12)H9A—C9—H9C109.5
C14—O4—C17118.03 (11)H9B—C9—H9C109.5
C2—C1—C6124.48 (12)C2—C10—H10A109.5
C2—C1—Cl1118.94 (10)C2—C10—H10B109.5
C6—C1—Cl1116.58 (10)H10A—C10—H10B109.5
C1—C2—C3116.76 (12)C2—C10—H10C109.5
C1—C2—C10120.28 (13)H10A—C10—H10C109.5
C3—C2—C10122.94 (12)H10B—C10—H10C109.5
C4—C3—C2119.62 (12)C12—C11—C16117.68 (12)
C4—C3—C8116.31 (12)C12—C11—C5121.30 (11)
C2—C3—C8124.06 (12)C16—C11—C5121.01 (11)
O1—C4—C5115.99 (11)C11—C12—C13121.91 (12)
O1—C4—C3122.28 (12)C11—C12—H12119.0
C5—C4—C3121.72 (12)C13—C12—H12119.0
C6—C5—C4118.97 (11)C14—C13—C12119.20 (12)
C6—C5—C11121.90 (11)C14—C13—H13120.4
C4—C5—C11119.13 (11)C12—C13—H13120.4
C5—C6—C1118.42 (12)O4—C14—C15115.94 (12)
C5—C6—C7121.32 (12)O4—C14—C13124.23 (12)
C1—C6—C7120.25 (12)C15—C14—C13119.83 (12)
C6—C7—H7A109.5C16—C15—C14120.05 (12)
C6—C7—H7B109.5C16—C15—H15120.0
H7A—C7—H7B109.5C14—C15—H15120.0
C6—C7—H7C109.5C15—C16—C11121.29 (12)
H7A—C7—H7C109.5C15—C16—H16119.4
H7B—C7—H7C109.5C11—C16—H16119.4
O2—C8—O3120.57 (12)O4—C17—H17A109.5
O2—C8—C3123.38 (12)O4—C17—H17B109.5
O3—C8—C3116.05 (12)H17A—C17—H17B109.5
O3—C9—H9A109.5O4—C17—H17C109.5
O3—C9—H9B109.5H17A—C17—H17C109.5
H9A—C9—H9B109.5H17B—C17—H17C109.5
C6—C1—C2—C3−1.3 (2)Cl1—C1—C6—C7−1.06 (16)
Cl1—C1—C2—C3178.26 (9)C9—O3—C8—O2−0.3 (2)
C6—C1—C2—C10177.07 (13)C9—O3—C8—C3179.38 (12)
Cl1—C1—C2—C10−3.41 (19)C4—C3—C8—O24.94 (19)
C1—C2—C3—C41.98 (18)C2—C3—C8—O2−174.47 (12)
C10—C2—C3—C4−176.30 (12)C4—C3—C8—O3−174.73 (10)
C1—C2—C3—C8−178.63 (11)C2—C3—C8—O35.86 (19)
C10—C2—C3—C83.1 (2)C6—C5—C11—C12−113.50 (15)
C2—C3—C4—O1177.11 (11)C4—C5—C11—C1266.49 (17)
C8—C3—C4—O1−2.32 (17)C6—C5—C11—C1665.53 (17)
C2—C3—C4—C5−1.34 (18)C4—C5—C11—C16−114.48 (14)
C8—C3—C4—C5179.22 (10)C16—C11—C12—C13−2.1 (2)
O1—C4—C5—C6−178.70 (10)C5—C11—C12—C13176.99 (12)
C3—C4—C5—C6−0.15 (18)C11—C12—C13—C140.9 (2)
O1—C4—C5—C111.31 (16)C17—O4—C14—C15−176.38 (12)
C3—C4—C5—C11179.86 (10)C17—O4—C14—C132.97 (19)
C4—C5—C6—C10.91 (17)C12—C13—C14—O4−178.45 (11)
C11—C5—C6—C1−179.10 (10)C12—C13—C14—C150.87 (19)
C4—C5—C6—C7−177.74 (11)O4—C14—C15—C16178.07 (12)
C11—C5—C6—C72.25 (18)C13—C14—C15—C16−1.3 (2)
C2—C1—C6—C5−0.19 (19)C14—C15—C16—C110.0 (2)
Cl1—C1—C6—C5−179.72 (9)C12—C11—C16—C151.6 (2)
C2—C1—C6—C7178.47 (12)C5—C11—C16—C15−177.44 (12)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O1—H1···O20.94 (2)1.63 (2)2.5061 (18)153 (2)
C7—H7C···Cl10.982.742.957 (2)93
C10—H10A···Cl10.982.453.003 (2)115
C10—H10B···O30.982.282.662 (2)102
C10—H10C···O30.982.572.662 (2)85
C9—H9A···O2i0.982.733.242 (3)113
C9—H9C···O2i0.982.963.242 (3)98
C15—H15···O4ii0.952.503.437 (2)170

Symmetry codes: (i) −x−1, −y+2, −z+1; (ii) −x+1, −y+1, −z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: PV2189).

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