supplementary materials


fj2644 scheme

Acta Cryst. (2013). E69, m588-m589    [ doi:10.1107/S1600536813026883 ]

Di­chlorido­{2-[(E)-phen­yl(pyridin-2-yl-[kappa]N)methyl­idene]-N-phenyl­hydra­zine­carboxamide-[kappa]2N2,O}copper(II)

N. Aiswarya, M. Sithambaresan, M. R. P. Kurup and S. W. Ng

Abstract top

The title compound, [CuCl2(C19H16N4O)], contains a CuII atom N,N',O-chelated by a neutral N-phenyl­hy­dra­zine­car­box­amide ligand and additionally coordinated by two Cl atoms, resulting in a distorted square-pyramidal geometry. The ligating atoms in the basal square plane of the complex comprise the azomethine N, the pyridine N, the amide O and one of the Cl atoms, whereas the other Cl atom occupies an apical position. The apical Cl atoms in adjacent layers function as hydrogen-bond acceptors to both NH groups. Intermolecular C-H...Cl and C-H...O interactions are also observed.

Comment top

Semicarbazones with versatile structural features are good ligands in both the neutral and anionic forms. Among the semicarbazones with diverse pharmacological activities (Beraldo & Gambino, 2004; Kasuga et al., 2006; Rivadeneira et al., 2009), the aryl semicarbazones were found to be devoid of sedative hypnotic activity and exhibited anticonvulsant activity with less neurotoxicity (Shalini et al., 2009). The biological activity can be attributed to their ability to form chelates with transition metal ions by bonding via 'O' and azomethine 'N' atoms. Also, the chlorido complex of imidazole-2-carbaldehyde semicarbazone has been found to exhibit antimicrobial activity (Rodriguez-Arguelles et al., 2010).

The title compound (Fig. 1) crystallizes in the triclinic space group P1. The molecule adopts an E configuration with respect to C6N2 bond and the tridentate ligand has its coordinating entities disposed in a cis fashion to each other.

The copper atom in the complex is N,N',O chelated by the neutral semicarbazone (Kunnath et al., 2012). The C6N2 [1.282 Å] and C13O1 [1.229 Å] bond distances are very close to the formal CN and CO bond lengths [CN; 1.28 Å and CO; 1.21 Å] respectively confirming the azomethine bond formation and existence of semicarbazone in amido form. In addition to bond length and bond angle analysis, the trigonality index value confirms the coordination polyhedron to be a distorted square pyramidal (Addison et al., 1984), with the apical chlorine atom out of the square plane by a distance of 2.450 Å. The apical chlorine atoms of the adjacent complex units function as hydrogen bond acceptors, generating a centrosymmetric dimer through a cyclic R21(6) association (Etter et al., 1990). In addition to that a non-classical intermolecular C–H···Cl and an intramolecular C–H···O hydrogen bonds are also present in the molecular system (Fig. 2, Table 1).

Three types of Cu—Cl···Cg interactions are present in the complex (Fig. 3) with X···Cg distances of 3.9266 (16), 3.5545 (11) and 3.1361 (13) Å,respectively. C—H···π and N—H···π interactions are altogether absent in the molecule. Since the CgCg distances are greater than 4 Å, the short ring interactions are not significant. Fig. 4 shows the packing diagram of the title compound along c axis.

Related literature top

For the biological applications of hydrazinecarboxamide and its derivatives, see: Beraldo & Gambino (2004); Kasuga et al. (2006); Rivadeneira et al. (2009); Shalini et al. (2009); Rodriguez-Arguelles et al. (2010). For the synthesis of related compounds, see: Kurup et al. (2011). For related structures, see: Kunnath et al. (2012). For the calculation of the trigonality index, see: Addison et al. 1984. For the graph-set notation, see: Etter et al. (1990).

Experimental top

The title compound was prepared by adapting a reported procedure (Kurup et al., 2011). To the semicarbazone ligand synthesized by refluxing a mixture of hot methanolic solutions (25 ml) of 4-phenylsemicarbazide (0.151 g, 1 mmol) and 2-benzoylpyridine (0.183 g, 1 mmol), hot filtered methanolic solution (25 ml) of CuCl2·2H2O (0.170 g, 1 mmol) was added and refluxed for 2 h. The resulting green solution was cooled to room temperature. Green block shaped crystals were collected, washed with few drops of methanol and dried over P4O10 in vacuo. Single crystals suitable for X-ray analysis were obtained after slow evaporation of solution in air for few days. The compound was obtained in 75% yield (0.3375 g).

Refinement top

All H atoms on C were placed in calculated positions, guided by difference maps, with C—H bond distances of 0.93 Å. H atoms were assigned Uiso(H) values of 1.2Ueq(carrier). Omitted owing to bad disagreement was reflection (0 0 1). H atoms of N3—H3' and N4—H4' bonds were located from difference maps and the bond distances are restrained to 0.88±0.02 Å.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2/SAINT (Bruker, 2004); data reduction: SAINT/XPREP (Bruker, 2004); program(s) used to solve structure: SHELXL97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 2012) and DIAMOND (Brandenburg, 2010); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. ORTEP view of the title compound, drawn with 50% probability displacement ellipsoids for the non-H atoms.
[Figure 2] Fig. 2. Graphical representation showing hydrogen-bonding interactions in the crystal structure of C19H16Cl2CuN4O.
[Figure 3] Fig. 3. Cu—Cl···π interaction found in the title compound.
[Figure 4] Fig. 4. A view of the unit cell along c axis.
Dichlorido{2-[(E)-phenyl(pyridin-2-yl-κN)methylidene]-N-phenylhydrazinecarboxamide-κ2N2,O}copper(II) top
Crystal data top
[CuCl2(C19H16N4O)]Z = 2
Mr = 450.81F(000) = 458
Triclinic, P1Dx = 1.530 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 9.4483 (5) ÅCell parameters from 3151 reflections
b = 9.8197 (3) Åθ = 2.5–27.7°
c = 11.5307 (4) ŵ = 1.41 mm1
α = 104.067 (1)°T = 293 K
β = 103.026 (1)°Block, green
γ = 100.475 (1)°0.35 × 0.32 × 0.30 mm
V = 978.83 (7) Å3
Data collection top
Bruker Kappa APEXII CCD
diffractometer
4411 independent reflections
Radiation source: fine-focus sealed tube3550 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.020
Detector resolution: 8.33 pixels mm-1θmax = 27.5°, θmin = 3.3°
ω and φ scanh = 912
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
k = 1212
Tmin = 0.614, Tmax = 0.649l = 1414
7149 measured reflections
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)] = 0.034Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.092H atoms treated by a mixture of independent and constrained refinement
S = 1.01 w = 1/[σ2(Fo2) + (0.0429P)2 + 0.3399P]
where P = (Fo2 + 2Fc2)/3
4411 reflections(Δ/σ)max = 0.001
252 parametersΔρmax = 0.34 e Å3
2 restraintsΔρmin = 0.40 e Å3
Crystal data top
[CuCl2(C19H16N4O)]γ = 100.475 (1)°
Mr = 450.81V = 978.83 (7) Å3
Triclinic, P1Z = 2
a = 9.4483 (5) ÅMo Kα radiation
b = 9.8197 (3) ŵ = 1.41 mm1
c = 11.5307 (4) ÅT = 293 K
α = 104.067 (1)°0.35 × 0.32 × 0.30 mm
β = 103.026 (1)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
4411 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
3550 reflections with I > 2σ(I)
Tmin = 0.614, Tmax = 0.649Rint = 0.020
7149 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.034H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.092Δρmax = 0.34 e Å3
S = 1.01Δρmin = 0.40 e Å3
4411 reflectionsAbsolute structure: ?
252 parametersAbsolute structure parameter: ?
2 restraintsRogers parameter: ?
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
Cu10.56784 (3)0.81865 (3)0.45210 (3)0.04217 (10)
Cl10.68970 (7)0.63456 (5)0.34892 (5)0.04308 (14)
Cl20.54712 (10)0.95006 (8)0.32265 (7)0.0657 (2)
O10.35179 (18)0.68219 (17)0.38879 (14)0.0435 (4)
N10.7528 (2)0.9491 (2)0.5849 (2)0.0474 (5)
N20.5556 (2)0.74344 (17)0.59382 (16)0.0343 (4)
N30.4287 (2)0.64128 (19)0.57491 (17)0.0385 (4)
H3'0.418 (3)0.593 (2)0.625 (2)0.048 (7)*
N40.2064 (2)0.5040 (2)0.43869 (19)0.0459 (5)
C10.8558 (4)1.0534 (3)0.5712 (3)0.0691 (9)
H10.84191.07330.49520.083*
C20.9811 (4)1.1309 (4)0.6673 (5)0.0930 (12)
H21.05141.20260.65630.112*
C31.0019 (4)1.1029 (4)0.7775 (4)0.0938 (12)
H31.08651.15550.84310.113*
C40.8967 (3)0.9953 (3)0.7934 (3)0.0712 (8)
H40.90980.97430.86900.085*
C50.7732 (3)0.9209 (2)0.6946 (2)0.0450 (5)
C60.6523 (2)0.8054 (2)0.7004 (2)0.0358 (4)
C70.6428 (2)0.7762 (2)0.81791 (19)0.0381 (5)
C80.6340 (3)0.8871 (3)0.9153 (2)0.0500 (6)
H80.63750.97930.90660.060*
C90.6203 (3)0.8607 (3)1.0242 (2)0.0596 (7)
H90.61280.93481.08840.071*
C100.6176 (3)0.7256 (3)1.0393 (2)0.0587 (7)
H100.60900.70881.11370.070*
C110.6275 (3)0.6155 (3)0.9440 (2)0.0564 (7)
H110.62630.52440.95440.068*
C120.6394 (3)0.6395 (3)0.8329 (2)0.0458 (5)
H120.64500.56440.76840.055*
C130.3276 (2)0.6125 (2)0.46062 (19)0.0364 (5)
C140.0774 (3)0.4486 (3)0.3355 (2)0.0467 (5)
C150.0277 (3)0.3329 (3)0.3403 (3)0.0649 (8)
H150.00970.29660.40810.078*
C160.1589 (4)0.2715 (4)0.2447 (4)0.0832 (10)
H160.22970.19490.24880.100*
C170.1846 (4)0.3227 (5)0.1446 (4)0.0988 (13)
H170.27190.27960.07930.119*
C180.0819 (4)0.4383 (5)0.1398 (4)0.0940 (12)
H180.10110.47430.07190.113*
C190.0509 (3)0.5020 (3)0.2357 (3)0.0664 (8)
H190.12060.57980.23190.080*
H4'0.210 (3)0.465 (3)0.496 (2)0.050 (8)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu10.05420 (19)0.03721 (16)0.04289 (17)0.00880 (12)0.02232 (13)0.01988 (12)
Cl10.0519 (3)0.0338 (3)0.0490 (3)0.0081 (2)0.0230 (3)0.0161 (2)
Cl20.0992 (6)0.0637 (4)0.0735 (4)0.0432 (4)0.0528 (4)0.0476 (4)
O10.0447 (9)0.0477 (9)0.0384 (8)0.0059 (7)0.0103 (7)0.0190 (7)
N10.0500 (12)0.0343 (9)0.0629 (13)0.0037 (9)0.0314 (10)0.0142 (9)
N20.0371 (10)0.0284 (8)0.0358 (9)0.0010 (7)0.0125 (8)0.0099 (7)
N30.0438 (11)0.0336 (9)0.0337 (9)0.0034 (8)0.0093 (8)0.0135 (7)
N40.0431 (11)0.0439 (11)0.0445 (11)0.0019 (9)0.0069 (9)0.0167 (9)
C10.069 (2)0.0500 (15)0.102 (2)0.0047 (14)0.0523 (19)0.0291 (15)
C20.057 (2)0.063 (2)0.156 (4)0.0107 (16)0.044 (2)0.033 (2)
C30.0433 (18)0.080 (2)0.129 (3)0.0197 (16)0.004 (2)0.024 (2)
C40.0431 (16)0.0650 (18)0.087 (2)0.0045 (13)0.0021 (15)0.0175 (16)
C50.0352 (12)0.0374 (11)0.0601 (15)0.0044 (9)0.0168 (11)0.0107 (10)
C60.0362 (11)0.0304 (10)0.0405 (11)0.0067 (8)0.0133 (9)0.0089 (8)
C70.0337 (11)0.0398 (11)0.0348 (11)0.0055 (9)0.0043 (9)0.0081 (9)
C80.0583 (16)0.0470 (13)0.0391 (12)0.0146 (12)0.0068 (11)0.0080 (10)
C90.0671 (19)0.0687 (18)0.0319 (12)0.0138 (14)0.0067 (12)0.0041 (11)
C100.0535 (16)0.081 (2)0.0347 (12)0.0047 (14)0.0041 (11)0.0220 (13)
C110.0546 (16)0.0560 (15)0.0559 (15)0.0024 (12)0.0057 (12)0.0291 (13)
C120.0495 (14)0.0413 (12)0.0434 (12)0.0069 (10)0.0105 (11)0.0124 (10)
C130.0398 (12)0.0319 (10)0.0367 (11)0.0070 (9)0.0122 (9)0.0089 (8)
C140.0369 (13)0.0430 (12)0.0529 (14)0.0084 (10)0.0097 (11)0.0049 (10)
C150.0482 (16)0.0527 (15)0.080 (2)0.0010 (13)0.0132 (14)0.0086 (14)
C160.0487 (18)0.070 (2)0.099 (3)0.0065 (15)0.0032 (18)0.0016 (19)
C170.051 (2)0.099 (3)0.099 (3)0.0014 (19)0.0168 (19)0.008 (2)
C180.072 (2)0.114 (3)0.077 (2)0.022 (2)0.0126 (19)0.026 (2)
C190.0487 (16)0.0738 (19)0.0654 (18)0.0083 (14)0.0001 (13)0.0205 (15)
Geometric parameters (Å, º) top
Cu1—N21.9672 (16)C6—C71.470 (3)
Cu1—N12.016 (2)C7—C121.390 (3)
Cu1—O12.0865 (16)C7—C81.391 (3)
Cu1—Cl22.1973 (6)C8—C91.370 (4)
Cu1—Cl12.5175 (6)C8—H80.9300
O1—C131.229 (3)C9—C101.376 (4)
N1—C51.339 (3)C9—H90.9300
N1—C11.344 (3)C10—C111.375 (4)
N2—C61.282 (3)C10—H100.9300
N2—N31.352 (2)C11—C121.383 (3)
N3—C131.372 (3)C11—H110.9300
N3—H3'0.846 (16)C12—H120.9300
N4—C131.343 (3)C14—C191.369 (4)
N4—C141.410 (3)C14—C151.388 (4)
N4—H4'0.833 (16)C15—C161.380 (4)
C1—C21.371 (5)C15—H150.9300
C1—H10.9300C16—C171.358 (5)
C2—C31.344 (6)C16—H160.9300
C2—H20.9300C17—C181.374 (6)
C3—C41.389 (4)C17—H170.9300
C3—H30.9300C18—C191.393 (4)
C4—C51.371 (4)C18—H180.9300
C4—H40.9300C19—H190.9300
C5—C61.483 (3)
N2—Cu1—N178.70 (7)C7—C6—C5122.45 (19)
N2—Cu1—O177.84 (6)C12—C7—C8119.4 (2)
N1—Cu1—O1154.03 (7)C12—C7—C6121.4 (2)
N2—Cu1—Cl2162.21 (6)C8—C7—C6119.2 (2)
N1—Cu1—Cl299.08 (6)C9—C8—C7120.0 (2)
O1—Cu1—Cl299.86 (5)C9—C8—H8120.0
N2—Cu1—Cl196.69 (5)C7—C8—H8120.0
N1—Cu1—Cl197.98 (6)C8—C9—C10120.7 (2)
O1—Cu1—Cl195.64 (5)C8—C9—H9119.6
Cl2—Cu1—Cl1101.09 (2)C10—C9—H9119.6
C13—O1—Cu1112.00 (14)C11—C10—C9119.7 (2)
C5—N1—C1119.2 (3)C11—C10—H10120.1
C5—N1—Cu1114.21 (15)C9—C10—H10120.1
C1—N1—Cu1126.5 (2)C10—C11—C12120.5 (2)
C6—N2—N3123.84 (17)C10—C11—H11119.8
C6—N2—Cu1120.05 (14)C12—C11—H11119.8
N3—N2—Cu1115.29 (13)C11—C12—C7119.7 (2)
N2—N3—C13113.53 (17)C11—C12—H12120.1
N2—N3—H3'122.5 (18)C7—C12—H12120.1
C13—N3—H3'123.5 (18)O1—C13—N4125.9 (2)
C13—N4—C14129.7 (2)O1—C13—N3120.75 (19)
C13—N4—H4'113.5 (19)N4—C13—N3113.39 (19)
C14—N4—H4'116.8 (19)C19—C14—C15119.9 (3)
N1—C1—C2121.2 (3)C19—C14—N4124.6 (2)
N1—C1—H1119.4C15—C14—N4115.5 (2)
C2—C1—H1119.4C16—C15—C14120.2 (3)
C3—C2—C1119.8 (3)C16—C15—H15119.9
C3—C2—H2120.1C14—C15—H15119.9
C1—C2—H2120.1C17—C16—C15120.1 (3)
C2—C3—C4119.9 (3)C17—C16—H16120.0
C2—C3—H3120.1C15—C16—H16120.0
C4—C3—H3120.1C16—C17—C18120.1 (3)
C5—C4—C3118.2 (3)C16—C17—H17120.0
C5—C4—H4120.9C18—C17—H17120.0
C3—C4—H4120.9C17—C18—C19120.6 (4)
N1—C5—C4121.8 (2)C17—C18—H18119.7
N1—C5—C6114.9 (2)C19—C18—H18119.7
C4—C5—C6123.3 (2)C14—C19—C18119.1 (3)
N2—C6—C7125.61 (19)C14—C19—H19120.4
N2—C6—C5111.80 (19)C18—C19—H19120.4
N2—Cu1—O1—C136.89 (15)N3—N2—C6—C5175.36 (19)
N1—Cu1—O1—C1332.7 (3)Cu1—N2—C6—C56.2 (2)
Cl2—Cu1—O1—C13168.91 (14)N1—C5—C6—N26.1 (3)
Cl1—Cu1—O1—C1388.77 (15)C4—C5—C6—N2174.4 (2)
N2—Cu1—N1—C50.20 (16)N1—C5—C6—C7169.7 (2)
O1—Cu1—N1—C525.9 (3)C4—C5—C6—C79.7 (4)
Cl2—Cu1—N1—C5162.26 (16)N2—C6—C7—C1261.0 (3)
Cl1—Cu1—N1—C595.08 (16)C5—C6—C7—C12123.7 (2)
N2—Cu1—N1—C1177.3 (2)N2—C6—C7—C8117.7 (3)
O1—Cu1—N1—C1157.0 (2)C5—C6—C7—C857.6 (3)
Cl2—Cu1—N1—C120.6 (2)C12—C7—C8—C90.8 (4)
Cl1—Cu1—N1—C182.0 (2)C6—C7—C8—C9177.9 (2)
N1—Cu1—N2—C63.66 (16)C7—C8—C9—C101.1 (4)
O1—Cu1—N2—C6165.14 (18)C8—C9—C10—C110.5 (4)
Cl2—Cu1—N2—C680.8 (3)C9—C10—C11—C120.4 (4)
Cl1—Cu1—N2—C6100.51 (16)C10—C11—C12—C70.7 (4)
N1—Cu1—N2—N3173.68 (16)C8—C7—C12—C110.1 (4)
O1—Cu1—N2—N34.88 (14)C6—C7—C12—C11178.8 (2)
Cl2—Cu1—N2—N389.2 (2)Cu1—O1—C13—N4171.66 (19)
Cl1—Cu1—N2—N389.48 (14)Cu1—O1—C13—N38.0 (3)
C6—N2—N3—C13167.1 (2)C14—N4—C13—O13.4 (4)
Cu1—N2—N3—C132.5 (2)C14—N4—C13—N3176.9 (2)
C5—N1—C1—C20.1 (4)N2—N3—C13—O14.0 (3)
Cu1—N1—C1—C2176.9 (2)N2—N3—C13—N4175.67 (19)
N1—C1—C2—C30.1 (6)C13—N4—C14—C191.9 (4)
C1—C2—C3—C40.2 (6)C13—N4—C14—C15178.9 (3)
C2—C3—C4—C50.3 (6)C19—C14—C15—C160.0 (5)
C1—N1—C5—C40.2 (4)N4—C14—C15—C16179.3 (3)
Cu1—N1—C5—C4177.2 (2)C14—C15—C16—C171.0 (5)
C1—N1—C5—C6179.3 (2)C15—C16—C17—C181.7 (6)
Cu1—N1—C5—C63.4 (3)C16—C17—C18—C191.4 (7)
C3—C4—C5—N10.3 (5)C15—C14—C19—C180.3 (5)
C3—C4—C5—C6179.1 (3)N4—C14—C19—C18179.5 (3)
N3—N2—C6—C70.4 (3)C17—C18—C19—C140.4 (6)
Cu1—N2—C6—C7169.48 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3···Cl1i0.85 (2)2.40 (2)3.1397 (18)147 (2)
N4—H4···Cl1i0.83 (2)2.35 (2)3.136 (2)159 (2)
C2—H2···Cl1ii0.932.693.589 (4)163
C19—H19···O10.932.362.953 (4)121
Symmetry codes: (i) x+1, y+1, z+1; (ii) x+2, y+2, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3'···Cl1i0.846 (16)2.40 (2)3.1397 (18)147 (2)
N4—H4'···Cl1i0.833 (16)2.345 (19)3.136 (2)159 (2)
C2—H2···Cl1ii0.93002.693.589 (4)163
C19—H19···O10.93002.362.953 (4)121
Symmetry codes: (i) x+1, y+1, z+1; (ii) x+2, y+2, z+1.
Acknowledgements top

NA thanks the University Grants Commission (India) for a Junior Research Fellowship. We thank the Sophisticated Analytical Instruments Facility, Cochin University of S&T, for the diffraction measurements. MRPK thanks the University Grants Commission, New Delhi, for a UGC–BSR one-time grant to faculty. We also thank the Ministry of Higher Education of Malaysia (grant No. UM.C/HIR/MOHE/SC/12) for supporting this study.

references
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