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Acta Crystallogr Sect E Struct Rep Online. 2009 June 1; 65(Pt 6): o1439–o1440.
Published online 2009 May 29. doi:  10.1107/S1600536809019436
PMCID: PMC2969694

(E)-3-[4-(Hex­yloxy)phen­yl]-1-(4-hydroxy­phen­yl)prop-2-en-1-one

Abstract

In the title compound, C21H24O3, the enone group adopts an scis conformation. The planes of the aromatic rings are inclined at an angle of 6.1 (1)°. The alk­oxy tail is not linear, with the maximum deviation from the least-squares plane being 0.375 (2) Å. Mol­ecules are connected into extended chains along the a axis through O—H(...)Ocarbon­yl hydrogen bonds and are inter­linked via C—H(...)O inter­actions to form a two-dimensional array parallel to the ab plane.

Related literature

For the biological properties of chalcone derivatives, see: Bhat et al. (2005 [triangle]); Xue et al. (2004 [triangle]); Zhao et al. (2005 [triangle]); Satyana­rayana et al. (2004 [triangle]); Won et al. (2005 [triangle]). For related structures, see: Razak et al. (2009 [triangle]); Razak et al. (2009a [triangle],b [triangle]); Ngaini, Fadzillah et al. (2009 [triangle]); Ngaini, Rahman et al. (2009 [triangle]). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-o1439-scheme1.jpg

Experimental

Crystal data

  • C21H24O3
  • M r = 324.40
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1439-efi1.jpg
  • a = 10.0237 (2) Å
  • b = 9.7695 (2) Å
  • c = 35.3220 (6) Å
  • V = 3458.96 (12) Å3
  • Z = 8
  • Mo Kα radiation
  • μ = 0.08 mm−1
  • T = 100 K
  • 0.25 × 0.12 × 0.07 mm

Data collection

  • Bruker SMART APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2005 [triangle]) T min = 0.980, T max = 0.995
  • 25370 measured reflections
  • 5659 independent reflections
  • 3311 reflections with I > 2σ(I)
  • R int = 0.086

Refinement

  • R[F 2 > 2σ(F 2)] = 0.073
  • wR(F 2) = 0.139
  • S = 1.02
  • 5659 reflections
  • 222 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.27 e Å−3
  • Δρmin = −0.25 e Å−3

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

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809019436/tk2457sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809019436/tk2457Isup2.hkl

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

Acknowledgments

HKF and IAR thank the Malaysian Government and Universiti Sains Malaysia for a Science Fund grant (No. 305/PFIZIK/613312) and a Research University Golden Goose grant (No. 1001/PFIZIK/811012). ZN and HH thank Universiti Malaysia Sarawak for a Geran Penyelidikan Dana Khas Inovasi grant [No. DI/01/2007(01)]. NIAR thanks the Malaysian Government and Universiti Malaysia Sarawak for providing a scholarship for postgraduate studies.

supplementary crystallographic information

Comment

Chalcones derivatives are reported to demonstrate biological properties such as an anti-malarial (Xue et al., 2004), anti-cancer (Bhat et al., 2005), anti-inflammatory (Won et al., 2005), anti-platelet (Zhao et al., 2005) as well as anti-hyperglycemic (Satyanarayana et al., 2004) activities. Synthetic and naturally occurring chalcones have been extensively studied and developed as pharmaceutically important molecules. As part of our studies, we have synthesized the title chalcone derivative, (I), and tested its anti-bacterial activity against E. coli ATCC 8739; the compound showed anti-microbial activity. In this paper, we report the crystal structure of (I).

The conformation of the enone (O2/C7–C9) moiety in (I) is scis with the O2—C7—C8—C9 torsion angle being 5.7 (3)°. The mean plane through the enone moiety makes dihedral angles of 15.9 (1)° and 10.9 (1)°, with the C1–C6 and C10–C15 aromatic rings, respectively. The two aromatic rings form a dihedral angle of 6.1 (1)°.

The short H1A···H8A (2.16 Å) contact resulted in the slight widening of the C1—C6—C7 (123.0 (2)°) and C6—C7—C8 (120.7 (2)°) angles whereas the widening of C8—C9—C10 and C9—C10—C15 angles to 129.0 (2)° and 123.7 (2)° respectively, resulted from the close interatomic contact of H8A···H15A (2.34 Å). Correspondingly, the opening of the O3—C13—C12 (124.9 (2)°) angle is the consequence of strain induced by short H12A···H16A (2.28 Å) and H12A···H16B (2.38 Å) contacts. Similar features can also be found in previously reported related structures (Razak et al., 2009; Razak et al., 2009a,b; Ngaini, Fadzillah et al., 2009; Ngaini, Rahman et al., 2009).

Even though the C16—O3—C13—C12 torsion angle is 0.8 (3)°, only part of the alkoxyl tail, O3/C16–C18, is co-planar with the attached aromatic ring [maximum deviation of the least-squares plane of O3/C16–C18 is -0.002 (2) Å]. The alkoxyl chain is twisted about the C19—C20 bond as shown by the C18—C19—C20—C21 torsion angle being -73.4 (2)°. The least-squares plane through the the alkoxyl chain, O3/C16–C21, [maximum deviation of 0.375 (2) Å at C16] makes a dihedral angle of 49.1 (2)° with the attached aromatic ring.

In the crystal structure, intermolecular O1—H1O1···O2 hydrogen bonds between the hydroxy and keto groups link the molecules into extended chains along the a axis, Table 1. The chains are interlinked via C1—H1A···O1 interactions into a 2-D array parallel to the ab-plane, Table 1 and Fig. 2.

Experimental

A mixture of 4-hydroxyacetophenone (1.36 g, 10 mmol), 4-hexyloxybenzaldehyde (2.06 ml, 10 mmol) and KOH (2.02 g, 36 mmol) in methanol (30 ml) was heated at reflux for 24 h. The reaction was cooled to room temperature and acidified with cold diluted HCl (2 N). The resulting precipitate was filtered, washed and dried. After redissolving in a hexane–ethanol (7:1) solution, followed by few days of slow evaporation, crystals were collected.

Refinement

The O-bound H atom was located in a difference Fourier map and refined freely; O—H = 0.89 (3) Å. All the C-bound H atoms were positioned geometrically and refined using a riding model with C—H = 0.93–0.97 Å. The Uiso values were constrained to be 1.5Ueq (methyl-H atoms) and 1.2Ueq (other H atoms). The rotating model group was applied for the methyl group.

Figures

Fig. 1.
The molecular structure of (I), showing 50% probability displacement ellipsoids and the atom numbering scheme.
Fig. 2.
The crystal packing in (I), viewed down the a axis. Intermolecular O—H···O hydrogen bonding and C—H···O contacts are shown as dashed lines. H atoms not involved in hydrogen bondings are omitted ...

Crystal data

C21H24O3F(000) = 1392
Mr = 324.40Dx = 1.246 Mg m3
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 2200 reflections
a = 10.0237 (2) Åθ = 2.3–22.0°
b = 9.7695 (2) ŵ = 0.08 mm1
c = 35.3220 (6) ÅT = 100 K
V = 3458.96 (12) Å3Block, colourless
Z = 80.25 × 0.12 × 0.07 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer5659 independent reflections
Radiation source: sealed tube3311 reflections with I > 2σ(I)
graphiteRint = 0.086
[var phi] and ω scansθmax = 31.3°, θmin = 1.2°
Absorption correction: multi-scan (SADABS; Bruker, 2005)h = −14→14
Tmin = 0.980, Tmax = 0.995k = −14→14
25370 measured reflectionsl = −51→50

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)] = 0.073Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.139H atoms treated by a mixture of independent and constrained refinement
S = 1.02w = 1/[σ2(Fo2) + (0.0389P)2 + 1.4637P] where P = (Fo2 + 2Fc2)/3
5659 reflections(Δ/σ)max < 0.001
222 parametersΔρmax = 0.27 e Å3
0 restraintsΔρmin = −0.25 e Å3

Special details

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems 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.

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

xyzUiso*/Ueq
O10.45711 (14)0.93154 (14)0.31262 (3)0.0203 (3)
O20.17214 (13)0.81942 (14)0.15690 (3)0.0216 (3)
O30.47446 (13)0.24927 (13)0.00413 (4)0.0207 (3)
C10.43756 (18)0.74282 (19)0.22313 (5)0.0177 (4)
H1A0.47830.66960.21090.021*
C20.47890 (19)0.77884 (18)0.25929 (5)0.0183 (4)
H2A0.54520.72860.27140.022*
C30.42085 (18)0.89013 (19)0.27736 (5)0.0172 (4)
C40.32103 (19)0.96503 (19)0.25923 (5)0.0198 (4)
H4A0.28271.04020.27120.024*
C50.27945 (18)0.92715 (19)0.22348 (5)0.0193 (4)
H5A0.21270.97730.21160.023*
C60.33582 (18)0.81466 (18)0.20480 (5)0.0163 (4)
C70.28184 (18)0.77389 (19)0.16745 (5)0.0175 (4)
C80.35542 (18)0.67861 (19)0.14301 (5)0.0177 (4)
H8A0.43360.63790.15160.021*
C90.30968 (18)0.65064 (19)0.10828 (5)0.0184 (4)
H9A0.23570.70100.10070.022*
C100.35965 (18)0.55225 (18)0.08071 (5)0.0169 (4)
C110.29114 (19)0.5369 (2)0.04661 (5)0.0201 (4)
H11A0.21970.59480.04150.024*
C120.32554 (19)0.43872 (19)0.02008 (5)0.0201 (4)
H12A0.27730.4303−0.00230.024*
C130.43319 (18)0.35286 (18)0.02730 (5)0.0176 (4)
C140.50604 (18)0.3682 (2)0.06095 (5)0.0193 (4)
H14A0.57950.31250.06550.023*
C150.46928 (18)0.46577 (19)0.08730 (5)0.0180 (4)
H15A0.51760.47430.10960.022*
C160.40164 (19)0.2288 (2)−0.03062 (5)0.0207 (4)
H16A0.40100.3125−0.04540.025*
H16B0.31010.2034−0.02510.025*
C170.47013 (19)0.11601 (19)−0.05233 (5)0.0211 (4)
H17A0.47080.0334−0.03710.025*
H17B0.56200.1420−0.05710.025*
C180.4013 (2)0.0863 (2)−0.08992 (5)0.0229 (4)
H18A0.38740.1717−0.10330.027*
H18B0.31450.0462−0.08500.027*
C190.48161 (19)−0.0107 (2)−0.11501 (5)0.0219 (4)
H19A0.4997−0.0939−0.10090.026*
H19B0.56670.0318−0.12080.026*
C200.4129 (2)−0.0490 (2)−0.15221 (5)0.0274 (5)
H20A0.37980.0336−0.16420.033*
H20B0.4781−0.0899−0.16910.033*
C210.2977 (2)−0.1482 (2)−0.14688 (6)0.0286 (5)
H21A0.2614−0.1722−0.17110.043*
H21B0.2297−0.1057−0.13170.043*
H21C0.3291−0.2292−0.13440.043*
H1O10.529 (3)0.886 (3)0.3205 (7)0.057 (8)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0221 (7)0.0227 (7)0.0162 (6)0.0010 (6)−0.0029 (6)−0.0022 (6)
O20.0217 (7)0.0263 (7)0.0169 (6)0.0043 (6)−0.0023 (5)−0.0003 (6)
O30.0243 (7)0.0219 (7)0.0160 (6)0.0026 (6)−0.0010 (5)−0.0046 (5)
C10.0195 (9)0.0155 (9)0.0182 (9)−0.0003 (8)0.0009 (8)−0.0010 (7)
C20.0206 (10)0.0158 (9)0.0184 (9)0.0010 (8)−0.0036 (8)0.0011 (7)
C30.0191 (9)0.0193 (9)0.0132 (8)−0.0041 (7)−0.0003 (7)0.0001 (7)
C40.0196 (9)0.0177 (9)0.0221 (9)0.0013 (8)0.0019 (8)−0.0025 (8)
C50.0192 (9)0.0193 (9)0.0194 (9)0.0008 (8)−0.0023 (7)−0.0002 (8)
C60.0179 (9)0.0163 (8)0.0148 (8)−0.0011 (7)0.0003 (7)0.0014 (7)
C70.0199 (9)0.0173 (9)0.0153 (9)−0.0027 (8)0.0010 (7)0.0023 (7)
C80.0172 (9)0.0183 (9)0.0175 (9)0.0012 (8)0.0004 (7)0.0023 (7)
C90.0179 (9)0.0194 (9)0.0178 (9)−0.0005 (7)0.0020 (7)0.0020 (8)
C100.0189 (9)0.0177 (9)0.0141 (8)−0.0026 (7)0.0012 (7)0.0015 (7)
C110.0201 (10)0.0217 (10)0.0184 (9)0.0016 (8)−0.0006 (8)0.0025 (8)
C120.0228 (10)0.0239 (10)0.0135 (8)−0.0005 (8)−0.0026 (8)−0.0007 (8)
C130.0211 (9)0.0161 (9)0.0155 (9)−0.0023 (7)0.0032 (7)0.0018 (7)
C140.0167 (9)0.0218 (9)0.0195 (9)0.0001 (8)0.0001 (7)0.0021 (8)
C150.0198 (9)0.0214 (9)0.0128 (8)−0.0032 (8)0.0001 (7)0.0017 (7)
C160.0235 (10)0.0228 (10)0.0157 (9)−0.0004 (8)−0.0013 (8)0.0010 (8)
C170.0238 (10)0.0208 (9)0.0188 (9)0.0022 (8)0.0017 (8)−0.0009 (8)
C180.0270 (11)0.0223 (10)0.0194 (9)0.0038 (8)0.0010 (8)−0.0017 (8)
C190.0253 (10)0.0203 (9)0.0201 (9)−0.0005 (8)0.0050 (8)−0.0014 (8)
C200.0399 (13)0.0245 (10)0.0178 (10)−0.0012 (10)0.0031 (9)−0.0018 (8)
C210.0344 (12)0.0286 (11)0.0228 (10)0.0021 (10)−0.0038 (9)−0.0021 (9)

Geometric parameters (Å, °)

O1—C31.359 (2)C12—C131.390 (3)
O1—H1O10.89 (3)C12—H12A0.9300
O2—C71.243 (2)C13—C141.403 (2)
O3—C131.366 (2)C14—C151.382 (3)
O3—C161.442 (2)C14—H14A0.9300
C1—C21.388 (2)C15—H15A0.9300
C1—C61.397 (2)C16—C171.508 (3)
C1—H1A0.9300C16—H16A0.9700
C2—C31.389 (2)C16—H16B0.9700
C2—H2A0.9300C17—C181.524 (3)
C3—C41.395 (3)C17—H17A0.9700
C4—C51.380 (2)C17—H17B0.9700
C4—H4A0.9300C18—C191.526 (3)
C5—C61.401 (2)C18—H18A0.9700
C5—H5A0.9300C18—H18B0.9700
C6—C71.481 (2)C19—C201.530 (3)
C7—C81.468 (3)C19—H19A0.9700
C8—C91.338 (2)C19—H19B0.9700
C8—H8A0.9300C20—C211.519 (3)
C9—C101.457 (2)C20—H20A0.9700
C9—H9A0.9300C20—H20B0.9700
C10—C111.394 (2)C21—H21A0.9600
C10—C151.405 (3)C21—H21B0.9600
C11—C121.385 (3)C21—H21C0.9600
C11—H11A0.9300
C3—O1—H1O1110.8 (17)C15—C14—H14A119.8
C13—O3—C16117.35 (14)C13—C14—H14A119.8
C2—C1—C6121.13 (17)C14—C15—C10120.75 (17)
C2—C1—H1A119.4C14—C15—H15A119.6
C6—C1—H1A119.4C10—C15—H15A119.6
C1—C2—C3119.76 (17)O3—C16—C17107.68 (15)
C1—C2—H2A120.1O3—C16—H16A110.2
C3—C2—H2A120.1C17—C16—H16A110.2
O1—C3—C2122.84 (16)O3—C16—H16B110.2
O1—C3—C4117.15 (16)C17—C16—H16B110.2
C2—C3—C4120.01 (16)H16A—C16—H16B108.5
C5—C4—C3119.72 (17)C16—C17—C18112.12 (16)
C5—C4—H4A120.1C16—C17—H17A109.2
C3—C4—H4A120.1C18—C17—H17A109.2
C4—C5—C6121.30 (17)C16—C17—H17B109.2
C4—C5—H5A119.4C18—C17—H17B109.2
C6—C5—H5A119.4H17A—C17—H17B107.9
C1—C6—C5118.05 (16)C17—C18—C19112.69 (16)
C1—C6—C7123.00 (16)C17—C18—H18A109.1
C5—C6—C7118.90 (16)C19—C18—H18A109.1
O2—C7—C8119.66 (16)C17—C18—H18B109.1
O2—C7—C6119.61 (16)C19—C18—H18B109.1
C8—C7—C6120.73 (16)H18A—C18—H18B107.8
C9—C8—C7119.77 (17)C18—C19—C20114.40 (17)
C9—C8—H8A120.1C18—C19—H19A108.7
C7—C8—H8A120.1C20—C19—H19A108.7
C8—C9—C10129.03 (18)C18—C19—H19B108.7
C8—C9—H9A115.5C20—C19—H19B108.7
C10—C9—H9A115.5H19A—C19—H19B107.6
C11—C10—C15117.62 (17)C21—C20—C19113.07 (16)
C11—C10—C9118.60 (17)C21—C20—H20A109.0
C15—C10—C9123.68 (16)C19—C20—H20A109.0
C12—C11—C10122.42 (18)C21—C20—H20B109.0
C12—C11—H11A118.8C19—C20—H20B109.0
C10—C11—H11A118.8H20A—C20—H20B107.8
C11—C12—C13119.14 (17)C20—C21—H21A109.5
C11—C12—H12A120.4C20—C21—H21B109.5
C13—C12—H12A120.4H21A—C21—H21B109.5
O3—C13—C12124.91 (16)C20—C21—H21C109.5
O3—C13—C14115.42 (16)H21A—C21—H21C109.5
C12—C13—C14119.66 (17)H21B—C21—H21C109.5
C15—C14—C13120.37 (18)
C6—C1—C2—C3−1.6 (3)C8—C9—C10—C150.9 (3)
C1—C2—C3—O1−179.56 (16)C15—C10—C11—C121.6 (3)
C1—C2—C3—C40.2 (3)C9—C10—C11—C12−174.97 (17)
O1—C3—C4—C5−179.55 (16)C10—C11—C12—C13−0.8 (3)
C2—C3—C4—C50.7 (3)C16—O3—C13—C120.8 (3)
C3—C4—C5—C6−0.2 (3)C16—O3—C13—C14179.42 (15)
C2—C1—C6—C52.0 (3)C11—C12—C13—O3177.71 (17)
C2—C1—C6—C7−175.46 (17)C11—C12—C13—C14−0.9 (3)
C4—C5—C6—C1−1.1 (3)O3—C13—C14—C15−177.06 (16)
C4—C5—C6—C7176.46 (17)C12—C13—C14—C151.7 (3)
C1—C6—C7—O2162.42 (17)C13—C14—C15—C10−0.8 (3)
C5—C6—C7—O2−15.0 (3)C11—C10—C15—C14−0.8 (3)
C1—C6—C7—C8−16.6 (3)C9—C10—C15—C14175.58 (17)
C5—C6—C7—C8165.93 (16)C13—O3—C16—C17176.52 (15)
O2—C7—C8—C95.7 (3)O3—C16—C17—C18−179.69 (15)
C6—C7—C8—C9−175.26 (17)C16—C17—C18—C19170.71 (16)
C7—C8—C9—C10−174.51 (17)C17—C18—C19—C20177.08 (17)
C8—C9—C10—C11177.22 (19)C18—C19—C20—C21−73.4 (2)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O1—H1O1···O2i0.89 (3)1.77 (3)2.6466 (19)169 (2)
C1—H1A···O1ii0.932.553.458 (2)164

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: TK2457).

References

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