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Acta Crystallogr Sect E Struct Rep Online. 2010 July 1; 66(Pt 7): o1811–o1812.
Published online 2010 June 26. doi:  10.1107/S160053681002369X
PMCID: PMC3006713

6-(4-Amino­phen­yl)-2-eth­oxy-4-(2-thien­yl)nicotinonitrile

Abstract

In the title nicotinonitrile derivative, C18H15N3OS, the central pyridyl ring makes dihedral angles of 25.22 (10) and 24.80 (16)° with the 4-amino­phenyl and thio­phene rings, respectively. The thio­phene ring is disordered over two orientations by rotation around the C(thio­phene)—C(pyridine) bond; the occupancies are 0.858 (2) and 0.142 (2). The eth­oxy group is slightly twisted from the attached pyridyl ring [C—O—C—C torsion angle = 171.13 (16)°]. In the crystal structure, mol­ecules are linked by N—H(...)N hydrogen bonds into chains along [010]. These chains are stacked along the a axis. C—H(...)π weak inter­actions involving the thio­phene ring are observed.

Related literature

For reference bond-length data, see: Allen et al. (1987 [triangle]). For the synthesis and applications of nicotinonitrile derivatives, see: Amr & Abdulla (2006 [triangle]); Borgna et al. (1993 [triangle]); Fun et al. (2009 [triangle]); Goda et al. (2004 [triangle]); Kamal et al. (2007 [triangle]); Malinka et al. (1998 [triangle]). For related structures, see: Chantrapromma et al. (2009 [triangle], 2010 [triangle]); Fun et al. (2009 [triangle]). For the stability of the temperature controller used in the data collection, see Cosier & Glazer (1986 [triangle]).

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Object name is e-66-o1811-scheme1.jpg

Experimental

Crystal data

  • C18H15N3OS
  • M r = 321.38
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1811-efi1.jpg
  • a = 7.0751 (12) Å
  • b = 20.843 (4) Å
  • c = 20.983 (4) Å
  • V = 3094.3 (9) Å3
  • Z = 8
  • Mo Kα radiation
  • μ = 0.22 mm−1
  • T = 100 K
  • 0.35 × 0.11 × 0.04 mm

Data collection

  • Bruker APEXII DUO CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2009 [triangle]) T min = 0.928, T max = 0.992
  • 34805 measured reflections
  • 3045 independent reflections
  • 2188 reflections with I > 2σ(I)
  • R int = 0.092

Refinement

  • R[F 2 > 2σ(F 2)] = 0.038
  • wR(F 2) = 0.085
  • S = 1.05
  • 3045 reflections
  • 233 parameters
  • 88 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.21 e Å−3
  • Δρmin = −0.32 e Å−3

Data collection: APEX2 (Bruker, 2009 [triangle]); cell refinement: SAINT (Bruker, 2009 [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/S160053681002369X/wn2394sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053681002369X/wn2394Isup2.hkl

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

Acknowledgments

The authors thank the Thailand Research Fund (TRF) and Prince of Songkla University for a research grant. AMI is grateful to the Head of the Department of Chemistry and the Director, NITK-Surathkal, India, for providing research facilities. The authors also thank Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012.

supplementary crystallographic information

Comment

Heterocyclic compounds containing the pyridine ring are reported to possess a diverse range of biological activities such as antimicrobial, antitumor and anti-inflammatory (Amr & Abdulla, 2006; Borgna et al., 1993; Goda et al., 2004; Kamal et al., 2007; Malinka et al., 1998) properties. Our research is aimed at the synthesis and preliminary biological (in vitro) and pharmacological (in vivo) screening, together with enzyme inhibitory activity, of the nicotinonitrile derivatives. The title compound, which is a substituted pyridine compound, was synthesized by cyclization of our previous chalcone derivative (Fun et al., 2009) and malononitrile.

The molecule of the title compound, C18H15N3OS, is not planar (Fig. 1). The central pyridyl ring is inclined to the 4-aminophenyl and thiophene rings with dihedral angles of 25.22 (10)° and 24.80 (16)°, respectively. The thiophene ring is disordered over two orientations by rotation around the C4—C5 bond, with occupancies of 0.858 (2) and 0.142 (1). The ethoxy group is twisted slightly from the attached pyridyl ring, as indicated by the torsion angles C14—O1—C16—C17 = 171.13 (16)° and C16—O1—C14—C15 = 179.01 (16) °. The bond distances agree with the literature values (Allen et al., 1987) and are comparable with those for related structures (Chantrapromma et al., 2009; 2010).

In the crystal structure, (Fig. 2), the molecules are linked by weak intermolecular N2—H1N2···N3 hydrogen bond (Table 1) into chains along [010]. These chains are stacked along the a axis. The crystal structure is further stabilized by C—H···π interactions (Table 1); Cg1 is the centroid of the C1–C4/S1 ring (major disorder component).

Experimental

(2E)-1-(4-Aminophenyl)-3-(2-thienyl)prop-2-en-1-one (0.34 g, 0.0015 mole) which was synthesized according to a previous procedure (Fun et al., 2009) was added with continuous stirring to a freshly prepared sodium alkoxide solution (0.0014 mole of sodium in 100 ml of ethanol). Malononitrile (1.30 g, 0.02 mol) was then added with continuous stirring at room temperature until the precipitate separated out. The resulting solid was filtered (yield 68%). Yellow plate-shaped single crystals of the title compound suitable for X-ray structure determination were recrystalized from ethanol by the slow evaporation of the solvent at room temperature over several days. Mp. 470–471 K.

Refinement

The amino H atoms were located in difference maps and refined isotropically. The remaining H atoms were positioned geometrically and allowed to ride on their parent atoms, with d(C—H) = 0.93 Å for aromatic, 0.97 for CH2 and 0.96 Å for CH3 atoms. The Uiso values were constrained to be 1.5Ueq of the carrier atom for methyl H atoms and 1.2Ueq for the remaining carbon-bound H atoms. A rotating group model was used for the methyl groups. Atoms S1, C1, C2, C3 of the thiophene ring are disordered over two positions by rotation about the C4—C5 bond; the occupancies are 0.858 (2) and 0.142 (2).

Figures

Fig. 1.
The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme. Hydrogen atoms are shown as spheres of arbitrary radius. The major and minor components of the disorder are shown by shaded and ...
Fig. 2.
The crystal packing of the title compound, viewed approximately along the c axis, showing chains along [010]. Hydrogen bonds are shown as dashed lines. Only the major disorder components are shown.

Crystal data

C18H15N3OSDx = 1.380 Mg m3
Mr = 321.38Melting point = 470–471 K
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 3045 reflections
a = 7.0751 (12) Åθ = 1.9–26.0°
b = 20.843 (4) ŵ = 0.22 mm1
c = 20.983 (4) ÅT = 100 K
V = 3094.3 (9) Å3Plate, yellow
Z = 80.35 × 0.11 × 0.04 mm
F(000) = 1344

Data collection

Bruker APEXII DUO CCD area-detector diffractometer3045 independent reflections
Radiation source: sealed tube2188 reflections with I > 2σ(I)
graphiteRint = 0.092
[var phi] and ω scansθmax = 26.0°, θmin = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2009)h = −8→8
Tmin = 0.928, Tmax = 0.992k = −25→24
34805 measured reflectionsl = −25→25

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)] = 0.038Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.085H atoms treated by a mixture of independent and constrained refinement
S = 1.05w = 1/[σ2(Fo2) + (0.0278P)2 + 1.8001P] where P = (Fo2 + 2Fc2)/3
3045 reflections(Δ/σ)max < 0.001
233 parametersΔρmax = 0.21 e Å3
88 restraintsΔρmin = −0.32 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*/UeqOcc. (<1)
O10.56053 (19)0.37231 (6)0.25979 (6)0.0190 (3)
N10.5847 (2)0.26630 (7)0.22980 (7)0.0163 (4)
N20.6671 (3)0.01670 (9)0.05279 (9)0.0245 (4)
N30.5866 (2)0.39328 (8)0.41791 (8)0.0245 (4)
C40.6016 (3)0.21000 (9)0.42677 (9)0.0167 (4)
S10.68410 (11)0.13404 (3)0.44617 (3)0.01858 (19)0.8583 (19)
C10.6115 (5)0.14171 (15)0.52389 (16)0.0192 (7)0.8583 (19)
H1A0.62700.11010.55470.023*0.8583 (19)
C20.5284 (8)0.1996 (2)0.53499 (16)0.0168 (8)0.8583 (19)
H2A0.48070.21240.57430.020*0.8583 (19)
C30.5240 (8)0.2374 (2)0.4797 (2)0.0231 (10)0.8583 (19)
H3A0.47180.27830.47910.028*0.8583 (19)
S1X0.5077 (14)0.2515 (4)0.4850 (4)0.0200 (18)*0.1417 (19)
C1X0.560 (5)0.1904 (12)0.5376 (10)0.021 (8)*0.1417 (19)
H1XA0.53490.19190.58100.025*0.1417 (19)
C2X0.643 (3)0.1399 (10)0.5079 (8)0.012 (5)*0.1417 (19)
H2XA0.67190.10110.52740.014*0.1417 (19)
C3X0.679 (3)0.1544 (8)0.4425 (9)0.0231 (10)0.14
H3XA0.74700.12840.41490.028*0.1417 (19)
C50.6017 (3)0.23136 (9)0.36009 (9)0.0163 (4)
C60.6082 (3)0.18612 (9)0.31136 (9)0.0176 (4)
H6A0.61970.14290.32170.021*
C70.5978 (3)0.20381 (9)0.24772 (9)0.0164 (4)
C80.6032 (3)0.15594 (9)0.19636 (9)0.0158 (4)
C90.5488 (3)0.09205 (9)0.20666 (9)0.0203 (4)
H9A0.50160.08000.24630.024*
C100.5641 (3)0.04666 (9)0.15893 (9)0.0201 (4)
H10A0.52530.00470.16660.024*
C110.6372 (3)0.06310 (9)0.09920 (9)0.0178 (4)
C120.6864 (3)0.12704 (9)0.08808 (9)0.0181 (4)
H12A0.73190.13920.04830.022*
C130.6680 (3)0.17231 (9)0.13553 (9)0.0171 (4)
H13A0.69950.21470.12690.021*
C140.5779 (3)0.30963 (9)0.27536 (9)0.0168 (4)
C150.5874 (3)0.29610 (9)0.34132 (9)0.0163 (4)
C160.5537 (3)0.38737 (9)0.19226 (9)0.0197 (4)
H16A0.45940.36110.17120.024*
H16B0.67540.37910.17270.024*
C170.5035 (3)0.45707 (9)0.18628 (10)0.0248 (5)
H17A0.50120.46890.14210.037*
H17B0.59610.48250.20820.037*
H17C0.38130.46440.20470.037*
C180.5861 (3)0.34927 (9)0.38470 (9)0.0181 (4)
H1N20.586 (3)−0.0177 (12)0.0555 (11)0.039 (7)*
H2N20.678 (3)0.0308 (10)0.0137 (11)0.029 (6)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0293 (7)0.0135 (7)0.0143 (7)0.0002 (6)0.0006 (6)0.0000 (6)
N10.0175 (8)0.0123 (9)0.0191 (9)−0.0004 (7)0.0020 (7)−0.0014 (7)
N20.0355 (10)0.0196 (10)0.0184 (9)−0.0040 (8)−0.0002 (9)−0.0040 (8)
N30.0352 (10)0.0189 (10)0.0195 (9)0.0024 (8)0.0004 (8)0.0006 (8)
C40.0162 (9)0.0156 (10)0.0182 (10)0.0001 (8)−0.0005 (8)0.0003 (8)
S10.0220 (3)0.0159 (4)0.0179 (3)0.0049 (3)0.0012 (2)0.0032 (3)
C10.0239 (16)0.0225 (16)0.0113 (15)0.0003 (12)0.0022 (13)0.0024 (13)
C20.015 (2)0.0202 (19)0.0150 (15)0.0005 (13)0.0000 (11)0.0003 (10)
C30.0245 (19)0.019 (2)0.025 (2)−0.0002 (17)0.0011 (13)−0.0016 (17)
C3X0.0245 (19)0.019 (2)0.025 (2)−0.0002 (17)0.0011 (13)−0.0016 (17)
C50.0132 (9)0.0181 (10)0.0177 (10)0.0004 (8)0.0000 (8)0.0014 (8)
C60.0178 (9)0.0123 (10)0.0227 (11)0.0007 (8)0.0019 (8)0.0005 (8)
C70.0136 (9)0.0154 (10)0.0202 (10)−0.0013 (8)0.0019 (8)−0.0003 (9)
C80.0157 (9)0.0144 (10)0.0172 (10)0.0012 (8)0.0009 (8)0.0002 (8)
C90.0222 (10)0.0195 (11)0.0192 (10)−0.0001 (9)0.0026 (8)0.0016 (9)
C100.0247 (10)0.0138 (10)0.0217 (11)−0.0015 (8)−0.0007 (9)0.0009 (8)
C110.0179 (10)0.0191 (10)0.0163 (10)0.0024 (8)−0.0038 (8)−0.0024 (8)
C120.0171 (9)0.0217 (11)0.0156 (10)−0.0017 (9)−0.0013 (8)0.0029 (8)
C130.0161 (9)0.0160 (10)0.0193 (10)−0.0005 (8)−0.0008 (8)0.0015 (8)
C140.0152 (9)0.0145 (11)0.0207 (10)0.0007 (8)0.0010 (8)0.0009 (8)
C150.0146 (9)0.0169 (10)0.0174 (10)0.0003 (8)0.0020 (8)−0.0015 (8)
C160.0265 (10)0.0186 (11)0.0141 (10)−0.0010 (9)0.0004 (8)0.0002 (8)
C170.0347 (12)0.0198 (11)0.0200 (11)0.0012 (9)0.0033 (9)0.0007 (9)
C180.0197 (10)0.0173 (11)0.0173 (10)0.0019 (8)0.0009 (8)0.0048 (9)

Geometric parameters (Å, °)

O1—C141.352 (2)C3X—H3XA0.9300
O1—C161.452 (2)C5—C61.392 (3)
N1—C141.316 (2)C5—C151.409 (3)
N1—C71.359 (2)C6—C71.387 (3)
N2—C111.389 (2)C6—H6A0.9300
N2—H1N20.92 (2)C7—C81.469 (3)
N2—H2N20.87 (2)C8—C131.398 (3)
N3—C181.152 (2)C8—C91.403 (3)
C4—C3X1.323 (14)C9—C101.382 (3)
C4—C31.364 (5)C9—H9A0.9300
C4—C51.468 (3)C10—C111.399 (3)
C4—S1X1.638 (8)C10—H10A0.9300
C4—S11.736 (2)C11—C121.397 (3)
S1—C11.717 (3)C12—C131.378 (3)
C1—C21.361 (4)C12—H12A0.9300
C1—H1A0.9300C13—H13A0.9300
C2—C31.404 (6)C14—C151.414 (3)
C2—H2A0.9300C15—C181.434 (3)
C3—H3A0.9300C16—C171.501 (3)
S1X—C1X1.725 (17)C16—H16A0.9700
C1X—C2X1.355 (16)C16—H16B0.9700
C1X—H1XA0.9300C17—H17A0.9600
C2X—C3X1.427 (17)C17—H17B0.9600
C2X—H2XA0.9300C17—H17C0.9600
C14—O1—C16116.59 (14)N1—C7—C8116.73 (17)
C14—N1—C7117.34 (16)C6—C7—C8121.62 (17)
C11—N2—H1N2113.9 (15)C13—C8—C9117.52 (17)
C11—N2—H2N2116.0 (14)C13—C8—C7120.83 (17)
H1N2—N2—H2N2112 (2)C9—C8—C7121.63 (17)
C3X—C4—C3109.2 (9)C10—C9—C8121.11 (18)
C3X—C4—C5120.2 (8)C10—C9—H9A119.4
C3—C4—C5130.5 (3)C8—C9—H9A119.4
C3X—C4—S1X116.3 (8)C9—C10—C11120.71 (18)
C5—C4—S1X123.5 (3)C9—C10—H10A119.6
C3—C4—S1109.1 (2)C11—C10—H10A119.6
C5—C4—S1119.99 (14)N2—C11—C12120.63 (18)
S1X—C4—S1116.3 (3)N2—C11—C10120.94 (18)
C1—S1—C492.13 (12)C12—C11—C10118.39 (17)
C2—C1—S1112.0 (3)C13—C12—C11120.61 (18)
C2—C1—H1A124.0C13—C12—H12A119.7
S1—C1—H1A124.0C11—C12—H12A119.7
C1—C2—C3111.5 (3)C12—C13—C8121.57 (18)
C1—C2—H2A124.3C12—C13—H13A119.2
C3—C2—H2A124.3C8—C13—H13A119.2
C4—C3—C2115.4 (4)N1—C14—O1119.39 (17)
C4—C3—H3A122.3N1—C14—C15124.92 (17)
C2—C3—H3A122.3O1—C14—C15115.69 (16)
C4—S1X—C1X90.0 (8)C5—C15—C14117.90 (17)
C2X—C1X—S1X111.9 (15)C5—C15—C18124.26 (17)
C2X—C1X—H1XA124.1C14—C15—C18117.83 (17)
S1X—C1X—H1XA124.1O1—C16—C17107.39 (15)
C1X—C2X—C3X110.7 (16)O1—C16—H16A110.2
C1X—C2X—H2XA124.6C17—C16—H16A110.2
C3X—C2X—H2XA124.6O1—C16—H16B110.2
C4—C3X—C2X110.6 (14)C17—C16—H16B110.2
C4—C3X—H3XA124.7H16A—C16—H16B108.5
C2X—C3X—H3XA124.7C16—C17—H17A109.5
C6—C5—C15116.48 (17)C16—C17—H17B109.5
C6—C5—C4119.64 (17)H17A—C17—H17B109.5
C15—C5—C4123.82 (17)C16—C17—H17C109.5
C7—C6—C5121.69 (18)H17A—C17—H17C109.5
C7—C6—H6A119.2H17B—C17—H17C109.5
C5—C6—H6A119.2N3—C18—C15177.8 (2)
N1—C7—C6121.64 (17)
C3X—C4—S1—C193 (10)C14—N1—C7—C6−1.5 (3)
C3—C4—S1—C10.1 (3)C14—N1—C7—C8179.37 (16)
C5—C4—S1—C1−172.59 (18)C5—C6—C7—N11.4 (3)
S1X—C4—S1—C11.6 (4)C5—C6—C7—C8−179.56 (17)
C4—S1—C1—C2−0.2 (3)N1—C7—C8—C1325.1 (3)
S1—C1—C2—C30.2 (5)C6—C7—C8—C13−154.02 (19)
C3X—C4—C3—C2−5.3 (12)N1—C7—C8—C9−156.59 (17)
C5—C4—C3—C2171.7 (3)C6—C7—C8—C924.3 (3)
S1X—C4—C3—C2−170 (5)C13—C8—C9—C101.9 (3)
S1—C4—C3—C2−0.1 (5)C7—C8—C9—C10−176.49 (18)
C1—C2—C3—C4−0.1 (7)C8—C9—C10—C111.0 (3)
C3X—C4—S1X—C1X−3(2)C9—C10—C11—N2174.78 (18)
C3—C4—S1X—C1X14 (4)C9—C10—C11—C12−2.9 (3)
C5—C4—S1X—C1X176.6 (14)N2—C11—C12—C13−175.82 (17)
S1—C4—S1X—C1X2.6 (15)C10—C11—C12—C131.8 (3)
C4—S1X—C1X—C2X−2(3)C11—C12—C13—C81.1 (3)
S1X—C1X—C2X—C3X6(4)C9—C8—C13—C12−2.9 (3)
C3—C4—C3X—C2X4(2)C7—C8—C13—C12175.46 (17)
C5—C4—C3X—C2X−173.0 (13)C7—N1—C14—O1−178.52 (15)
S1X—C4—C3X—C2X6(2)C7—N1—C14—C151.5 (3)
S1—C4—C3X—C2X−85 (10)C16—O1—C14—N1−1.0 (2)
C1X—C2X—C3X—C4−8(3)C16—O1—C14—C15179.01 (16)
C3X—C4—C5—C626.4 (13)C6—C5—C15—C140.9 (3)
C3—C4—C5—C6−150.2 (4)C4—C5—C15—C14−176.28 (17)
S1X—C4—C5—C6−153.1 (5)C6—C5—C15—C18−177.58 (17)
S1—C4—C5—C620.7 (2)C4—C5—C15—C185.2 (3)
C3X—C4—C5—C15−156.5 (12)N1—C14—C15—C5−1.2 (3)
C3—C4—C5—C1526.9 (4)O1—C14—C15—C5178.77 (16)
S1X—C4—C5—C1524.1 (5)N1—C14—C15—C18177.37 (17)
S1—C4—C5—C15−162.13 (15)O1—C14—C15—C18−2.6 (3)
C15—C5—C6—C7−1.0 (3)C14—O1—C16—C17171.13 (16)
C4—C5—C6—C7176.29 (17)

Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the major disorder component of the thiophene ring.
D—H···AD—HH···AD···AD—H···A
N2—H1N2···N3i0.92 (2)2.29 (2)3.197 (3)168.2 (19)
C3—H3A···Cg1ii0.932.933.566 (6)127
C12—H12A···Cg1iii0.932.783.430 (3)128

Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) −x−1, y+1/2, −z+3/2; (iii) x−1/2, y, −z−1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: WN2394).

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