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Acta Crystallogr Sect E Struct Rep Online. Jun 1, 2012; 68(Pt 6): o1863.
Published online May 23, 2012. doi:  10.1107/S1600536812022192
PMCID: PMC3379429
Ethyl 2-(4-chloro­phen­yl)-1-phenyl-1H-benzimidazole-5-carboxyl­ate
Yeong Keng Yoon,a Elumalai Manogaran,b Tan Soo Choon,a Suhana Arshad,c and Ibrahim Abdul Razakc*
aInstitute for Research in Molecular Medicine, Universiti Sains Malaysia, Minden 11800, Penang, Malaysia
bDepartment of Pharmaceutical Sciences, UCSI University, Kuala Lumpur, Cheras 56000, Malaysia
cSchool of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
Correspondence e-mail: arazaki/at/usm.my
Thomson Reuters ResearcherID: A-5599-2009.
Received May 7, 2012; Accepted May 16, 2012.
Abstract
In the title compound, C22H17ClN2O2, the essentially planar benzimidazole ring system [maximum deviation = 0.012 (2) Å] forms dihedral angles of 28.69 (6) and 63.65 (7)°, respectively, with the phenyl and chloro-substituted benzene rings. The dihedral angle between the phenyl and benzene rings is 64.23 (8)°. In the crystal, mol­ecules are linked into a zigzag chain along the a axis by inter­molecular C—H(...)O hydrogen bonds. C—H(...)π inter­actions are also present.
Related literature  
For applications of benzimidazoles, see: Tanious et al. (2004 [triangle]); Townsend & Revankar (1970 [triangle]). For related structures, see: Yoon et al. (2011 [triangle], 2012 [triangle]); Kassim et al. (2012 [triangle]). For stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 [triangle]).
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Object name is e-68-o1863-scheme1.jpg Object name is e-68-o1863-scheme1.jpg
Crystal data  
  • C22H17ClN2O2
  • M r = 376.83
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-68-o1863-efi1.jpg
  • a = 9.3357 (2) Å
  • b = 9.7982 (2) Å
  • c = 11.7718 (4) Å
  • α = 107.502 (2)°
  • β = 102.106 (2)°
  • γ = 109.539 (1)°
  • V = 908.31 (4) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.23 mm−1
  • T = 100 K
  • 0.38 × 0.29 × 0.24 mm
Data collection  
  • Bruker SMART APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2009 [triangle]) T min = 0.917, T max = 0.946
  • 18472 measured reflections
  • 5326 independent reflections
  • 4233 reflections with I > 2σ(I)
  • R int = 0.033
Refinement  
  • R[F 2 > 2σ(F 2)] = 0.048
  • wR(F 2) = 0.127
  • S = 1.04
  • 5326 reflections
  • 245 parameters
  • H-atom parameters constrained
  • Δρmax = 0.57 e Å−3
  • Δρmin = −0.31 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
Table 1
Hydrogen-bond geometry (Å, °)
Supplementary Material
Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536812022192/is5137sup1.cif
Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812022192/is5137Isup2.hkl
Supplementary material file. DOI: 10.1107/S1600536812022192/is5137Isup3.cml
Additional supplementary materials: crystallographic information; 3D view; checkCIF report
Acknowledgments
The authors thank the Malaysian Government and Universiti Sains Malaysia (USM) for the Research University Grant Nos.1001/PFIZIK/811151 and 1001/PSK/8620012. The authors also wish to express their thanks to the Pharmacogenetic and Novel Therapeutic Research, Institute for Research in Mol­ecular Medicine, Universiti Sains Malaysia. SA also thanks the Malaysian Government and USM for an Academic Staff Training Scheme (ASTS) fellowship.
supplementary crystallographic information
Comment
Substituted benzimidazoles are proven important drug leads. Substituted benzimidazole is the key building block for numerous compounds which plays crucial roles in the function of biologically important molecules (Tanious et al., 2004). In particular, 2-substituted benzimidazoles are recognized as potential anticancer agents (Townsend & Revankar, 1970). As part of our ongoing structural studies of benzimidazole derivatives (Yoon et al., 2011), we now report the structure of the title compound.
In the molecular structure (Fig. 1), The benzimidazole ring system (N1/N2/C1—C7) is essentially planar with a maximum deviation of 0.012 (2) Å at atom C1 and forms dihedral angles of 28.69 (6) and 63.65 (7)°, respectively, with the phenyl (C8–C13) and chloro-substituted benzene (C14–C19) ring. The dihedral angle between the phenyl ring and the chloro-substituted benzene ring is 64.23 (8)°. Bond lengths and angles are within normal ranges and are comparable to related structures (Yoon et al., 2011; Kassim et al., 2012; Yoon et al., 2012).
The crystal packing is shown in Fig. 2. The molecules are linked into a zigzag chain along the a-axis via intermolecular C15—H15A···O2 (Table 1) hydrogen bonds. The crystal structure is further stabilized by intermolecular C21—H21A···Cg1, C1—H12A···Cg2 and C19—H19A···Cg3 (Table 1) interactions (Cg1, Cg2 and Cg3 are the centroids of N1/N2/C1/C6/C7, C1–C6 and C8–C13 rings, respectively).
Experimental
Ethyl 3-amino-4-(phenyl amino) benzoate (0.84 mmol) and sodium metabisulfite adduct of chlorobenzaldehyde (1.68 mmol) were dissolved in DMF. The reaction mixture was reflux at 130 °C for 2 h. After completion, the reaction mixture was diluted in ethyl acetate (20 ml) and washed with water (20 ml). The organic layer was collected, dried over Na2SO4 and the evaporated in-vacuo to yield the product. The product was recrystallized from ethyl acetate.
Refinement
All H atoms were positioned geometrically (C—H = 0.95–0.99 Å) and refined using a riding model with Uiso(H) = 1.2 and 1.5Ueq(C). A rotating group model was applied to the methyl group.
Figures
Fig. 1.
Fig. 1.
The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme.
Fig. 2.
Fig. 2.
A crystal packing diagram of the title compound viewed along the b axis. The H atoms not involved in the intermolecular interactions (dashed lines) have been omitted for clarity.
Crystal data
C22H17ClN2O2Z = 2
Mr = 376.83F(000) = 392
Triclinic, P1Dx = 1.378 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 9.3357 (2) ÅCell parameters from 7225 reflections
b = 9.7982 (2) Åθ = 2.6–30.2°
c = 11.7718 (4) ŵ = 0.23 mm1
α = 107.502 (2)°T = 100 K
β = 102.106 (2)°Block, colourless
γ = 109.539 (1)°0.38 × 0.29 × 0.24 mm
V = 908.31 (4) Å3
Data collection
Bruker SMART APEXII CCD area-detector diffractometer5326 independent reflections
Radiation source: fine-focus sealed tube4233 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.033
[var phi] and ω scansθmax = 30.2°, θmin = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2009)h = −13→13
Tmin = 0.917, Tmax = 0.946k = −13→13
18472 measured reflectionsl = −14→16
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)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.127H-atom parameters constrained
S = 1.04w = 1/[σ2(Fo2) + (0.0648P)2 + 0.3753P] where P = (Fo2 + 2Fc2)/3
5326 reflections(Δ/σ)max < 0.001
245 parametersΔρmax = 0.57 e Å3
0 restraintsΔρmin = −0.31 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
Cl1−0.66895 (5)−0.31206 (5)−0.07003 (4)0.02705 (11)
O10.66316 (12)−0.10624 (12)0.40052 (10)0.0196 (2)
O20.84606 (13)0.14573 (13)0.46871 (11)0.0229 (2)
N10.11793 (15)−0.10887 (14)0.20878 (12)0.0173 (2)
N20.16095 (14)0.14100 (14)0.23348 (12)0.0158 (2)
C10.31182 (17)0.14553 (17)0.28366 (14)0.0165 (3)
C20.46660 (18)0.26942 (17)0.34187 (14)0.0190 (3)
H2A0.48480.37440.35200.023*
C30.59248 (18)0.23218 (18)0.38427 (15)0.0201 (3)
H3A0.69970.31360.42490.024*
C40.56507 (17)0.07571 (17)0.36849 (14)0.0179 (3)
C50.41041 (18)−0.04706 (17)0.31022 (14)0.0180 (3)
H5A0.3924−0.15210.29970.022*
C60.28203 (17)−0.01073 (17)0.26755 (13)0.0165 (3)
C70.04967 (17)−0.01571 (16)0.19011 (13)0.0159 (3)
C8−0.12637 (17)−0.07740 (17)0.12872 (13)0.0158 (3)
C9−0.22379 (18)−0.21369 (17)0.13982 (14)0.0178 (3)
H9A−0.1746−0.25850.18810.021*
C10−0.39041 (19)−0.28384 (18)0.08158 (14)0.0199 (3)
H10A−0.4559−0.37390.09190.024*
C11−0.46027 (18)−0.21990 (18)0.00743 (14)0.0192 (3)
C12−0.36672 (18)−0.08703 (18)−0.00704 (14)0.0186 (3)
H12A−0.4161−0.0458−0.05880.022*
C13−0.19981 (18)−0.01465 (17)0.05489 (13)0.0171 (3)
H13A−0.13540.07790.04700.021*
C140.13273 (17)0.27784 (17)0.23909 (13)0.0163 (3)
C150.04178 (18)0.32176 (18)0.31023 (14)0.0188 (3)
H15A−0.00400.26070.35340.023*
C160.01898 (19)0.45680 (19)0.31695 (15)0.0223 (3)
H16A−0.04170.48880.36610.027*
C170.0840 (2)0.54544 (18)0.25259 (16)0.0242 (3)
H17A0.06750.63740.25770.029*
C180.1728 (2)0.49899 (19)0.18094 (16)0.0246 (3)
H18A0.21610.55860.13600.029*
C190.19904 (19)0.36522 (18)0.17450 (14)0.0204 (3)
H19A0.26140.33430.12660.024*
C200.70739 (18)0.04619 (17)0.41852 (14)0.0171 (3)
C210.79321 (18)−0.14740 (18)0.44432 (14)0.0188 (3)
H21A0.8447−0.09280.53780.023*
H21B0.8767−0.11650.40560.023*
C220.7175 (2)−0.32370 (19)0.40427 (16)0.0254 (3)
H22A0.8013−0.35780.43170.038*
H22B0.6667−0.37590.31170.038*
H22C0.6354−0.35230.44330.038*
Atomic displacement parameters (Å2)
U11U22U33U12U13U23
Cl10.01444 (18)0.0278 (2)0.0327 (2)0.00672 (15)0.00290 (15)0.01040 (16)
O10.0137 (5)0.0191 (5)0.0244 (5)0.0072 (4)0.0042 (4)0.0082 (4)
O20.0151 (5)0.0228 (5)0.0280 (6)0.0061 (5)0.0055 (4)0.0100 (5)
N10.0149 (6)0.0164 (6)0.0196 (6)0.0061 (5)0.0041 (5)0.0077 (5)
N20.0141 (6)0.0151 (5)0.0192 (6)0.0060 (5)0.0063 (5)0.0079 (5)
C10.0151 (6)0.0175 (6)0.0181 (6)0.0073 (6)0.0064 (5)0.0081 (5)
C20.0180 (7)0.0154 (6)0.0228 (7)0.0060 (6)0.0073 (6)0.0078 (6)
C30.0152 (7)0.0189 (7)0.0237 (7)0.0049 (6)0.0067 (6)0.0082 (6)
C40.0152 (7)0.0201 (7)0.0187 (7)0.0073 (6)0.0056 (5)0.0084 (6)
C50.0169 (7)0.0170 (6)0.0206 (7)0.0074 (6)0.0064 (6)0.0080 (5)
C60.0155 (6)0.0163 (6)0.0173 (6)0.0062 (6)0.0059 (5)0.0067 (5)
C70.0163 (6)0.0150 (6)0.0156 (6)0.0057 (6)0.0053 (5)0.0064 (5)
C80.0144 (6)0.0159 (6)0.0152 (6)0.0062 (5)0.0042 (5)0.0045 (5)
C90.0177 (7)0.0179 (6)0.0172 (6)0.0069 (6)0.0057 (5)0.0073 (5)
C100.0190 (7)0.0202 (7)0.0194 (7)0.0066 (6)0.0076 (6)0.0080 (6)
C110.0140 (6)0.0224 (7)0.0180 (7)0.0076 (6)0.0047 (5)0.0048 (6)
C120.0182 (7)0.0217 (7)0.0177 (7)0.0114 (6)0.0058 (5)0.0071 (5)
C130.0183 (7)0.0170 (6)0.0176 (7)0.0082 (6)0.0072 (5)0.0075 (5)
C140.0161 (6)0.0151 (6)0.0169 (6)0.0065 (6)0.0040 (5)0.0066 (5)
C150.0172 (7)0.0196 (7)0.0190 (7)0.0074 (6)0.0058 (6)0.0076 (6)
C160.0189 (7)0.0221 (7)0.0254 (8)0.0111 (6)0.0068 (6)0.0067 (6)
C170.0225 (8)0.0173 (7)0.0295 (8)0.0094 (6)0.0027 (6)0.0086 (6)
C180.0305 (8)0.0183 (7)0.0253 (8)0.0089 (7)0.0084 (7)0.0119 (6)
C190.0240 (8)0.0191 (7)0.0202 (7)0.0092 (6)0.0099 (6)0.0090 (6)
C200.0154 (6)0.0198 (7)0.0181 (7)0.0078 (6)0.0081 (5)0.0083 (5)
C210.0154 (7)0.0219 (7)0.0198 (7)0.0097 (6)0.0049 (5)0.0081 (6)
C220.0282 (8)0.0247 (8)0.0256 (8)0.0139 (7)0.0083 (7)0.0110 (6)
Geometric parameters (Å, º)
Cl1—C111.7393 (15)C10—C111.394 (2)
O1—C201.3440 (17)C10—H10A0.9500
O1—C211.4466 (17)C11—C121.386 (2)
O2—C201.2101 (18)C12—C131.391 (2)
N1—C71.3186 (18)C12—H12A0.9500
N1—C61.3858 (19)C13—H13A0.9500
N2—C11.3885 (17)C14—C191.389 (2)
N2—C71.3916 (18)C14—C151.390 (2)
N2—C141.4359 (17)C15—C161.391 (2)
C1—C21.394 (2)C15—H15A0.9500
C1—C61.4057 (19)C16—C171.390 (2)
C2—C31.383 (2)C16—H16A0.9500
C2—H2A0.9500C17—C181.386 (2)
C3—C41.413 (2)C17—H17A0.9500
C3—H3A0.9500C18—C191.395 (2)
C4—C51.389 (2)C18—H18A0.9500
C4—C201.4923 (19)C19—H19A0.9500
C5—C61.3985 (19)C21—C221.503 (2)
C5—H5A0.9500C21—H21A0.9900
C7—C81.471 (2)C21—H21B0.9900
C8—C131.3990 (19)C22—H22A0.9800
C8—C91.403 (2)C22—H22B0.9800
C9—C101.384 (2)C22—H22C0.9800
C9—H9A0.9500
C20—O1—C21115.83 (11)C11—C12—H12A120.3
C7—N1—C6105.12 (12)C13—C12—H12A120.3
C1—N2—C7106.08 (11)C12—C13—C8120.38 (14)
C1—N2—C14124.39 (12)C12—C13—H13A119.8
C7—N2—C14129.30 (12)C8—C13—H13A119.8
N2—C1—C2131.98 (13)C19—C14—C15121.23 (13)
N2—C1—C6105.41 (12)C19—C14—N2119.15 (13)
C2—C1—C6122.60 (13)C15—C14—N2119.61 (13)
C3—C2—C1116.80 (13)C14—C15—C16118.77 (14)
C3—C2—H2A121.6C14—C15—H15A120.6
C1—C2—H2A121.6C16—C15—H15A120.6
C2—C3—C4121.44 (14)C17—C16—C15120.81 (14)
C2—C3—H3A119.3C17—C16—H16A119.6
C4—C3—H3A119.3C15—C16—H16A119.6
C5—C4—C3121.36 (13)C18—C17—C16119.67 (14)
C5—C4—C20120.65 (13)C18—C17—H17A120.2
C3—C4—C20117.98 (13)C16—C17—H17A120.2
C4—C5—C6117.73 (13)C17—C18—C19120.38 (15)
C4—C5—H5A121.1C17—C18—H18A119.8
C6—C5—H5A121.1C19—C18—H18A119.8
N1—C6—C5129.46 (13)C14—C19—C18119.13 (14)
N1—C6—C1110.46 (12)C14—C19—H19A120.4
C5—C6—C1120.07 (13)C18—C19—H19A120.4
N1—C7—N2112.93 (12)O2—C20—O1123.55 (13)
N1—C7—C8121.50 (13)O2—C20—C4124.85 (13)
N2—C7—C8125.57 (12)O1—C20—C4111.60 (12)
C13—C8—C9118.95 (13)O1—C21—C22106.27 (12)
C13—C8—C7124.14 (13)O1—C21—H21A110.5
C9—C8—C7116.79 (12)C22—C21—H21A110.5
C10—C9—C8121.07 (13)O1—C21—H21B110.5
C10—C9—H9A119.5C22—C21—H21B110.5
C8—C9—H9A119.5H21A—C21—H21B108.7
C9—C10—C11118.76 (14)C21—C22—H22A109.5
C9—C10—H10A120.6C21—C22—H22B109.5
C11—C10—H10A120.6H22A—C22—H22B109.5
C12—C11—C10121.37 (14)C21—C22—H22C109.5
C12—C11—Cl1119.89 (11)H22A—C22—H22C109.5
C10—C11—Cl1118.73 (12)H22B—C22—H22C109.5
C11—C12—C13119.42 (13)
C7—N2—C1—C2−178.88 (15)C13—C8—C9—C10−1.5 (2)
C14—N2—C1—C2−4.0 (2)C7—C8—C9—C10−177.72 (13)
C7—N2—C1—C6−0.11 (15)C8—C9—C10—C112.2 (2)
C14—N2—C1—C6174.80 (13)C9—C10—C11—C12−1.1 (2)
N2—C1—C2—C3178.50 (15)C9—C10—C11—Cl1177.86 (11)
C6—C1—C2—C3−0.1 (2)C10—C11—C12—C13−0.8 (2)
C1—C2—C3—C40.3 (2)Cl1—C11—C12—C13−179.71 (11)
C2—C3—C4—C5−0.3 (2)C11—C12—C13—C81.5 (2)
C2—C3—C4—C20−179.22 (14)C9—C8—C13—C12−0.4 (2)
C3—C4—C5—C6−0.1 (2)C7—C8—C13—C12175.52 (13)
C20—C4—C5—C6178.85 (13)C1—N2—C14—C1965.11 (19)
C7—N1—C6—C5179.06 (15)C7—N2—C14—C19−121.21 (16)
C7—N1—C6—C1−0.26 (16)C1—N2—C14—C15−114.00 (16)
C4—C5—C6—N1−178.95 (14)C7—N2—C14—C1559.7 (2)
C4—C5—C6—C10.3 (2)C19—C14—C15—C16−0.6 (2)
N2—C1—C6—N10.23 (16)N2—C14—C15—C16178.49 (13)
C2—C1—C6—N1179.15 (13)C14—C15—C16—C170.8 (2)
N2—C1—C6—C5−179.16 (13)C15—C16—C17—C18−0.1 (2)
C2—C1—C6—C5−0.2 (2)C16—C17—C18—C19−0.8 (2)
C6—N1—C7—N20.19 (16)C15—C14—C19—C18−0.3 (2)
C6—N1—C7—C8179.89 (13)N2—C14—C19—C18−179.41 (14)
C1—N2—C7—N1−0.05 (16)C17—C18—C19—C141.0 (2)
C14—N2—C7—N1−174.62 (13)C21—O1—C20—O2−0.5 (2)
C1—N2—C7—C8−179.73 (13)C21—O1—C20—C4179.16 (12)
C14—N2—C7—C85.7 (2)C5—C4—C20—O2178.84 (15)
N1—C7—C8—C13−149.37 (15)C3—C4—C20—O2−2.2 (2)
N2—C7—C8—C1330.3 (2)C5—C4—C20—O1−0.83 (19)
N1—C7—C8—C926.6 (2)C3—C4—C20—O1178.10 (13)
N2—C7—C8—C9−153.74 (14)C20—O1—C21—C22−175.16 (12)
Hydrogen-bond geometry (Å, º)
Cg1, Cg2 and Cg3 are the centroids of the N1/C7/N2/C1/C6, C1–C6 and C8–C13 rings, respectively.
D—H···AD—HH···AD···AD—H···A
C15—H15A···O2i0.952.393.324 (2)166
C21—H21A···Cg1ii0.992.633.5183 (16)149
C12—H12A···Cg2iii0.952.963.5940 (16)125
C19—H19A···Cg3iii0.952.603.4770 (18)153
Symmetry codes: (i) x−1, y, z; (ii) −x+1, −y, −z+1; (iii) −x, −y, −z.
Footnotes
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: IS5137).
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