I. INTRODUCTION
The platinum (Pt) cytostatics are one of the most frequently used medications for the treatment of cancer. The first Pt cytostatic was based on Pt complexes with oxidation stage (II) and was called cisplatin cis–diaminodichloro-platinum (Matthew and Trevor, Reference Matthew and Trevor2002). This cytostatic has a high cytotoxicity but on the other hand it has many side effects as neurotoxicity, nephrotoxicity, etc. (Galanski et al., Reference Galanski, Arion, Jakupec and Keppler2003). A new strategy for the development of Pt complexes is represented by a new group of complexes where Pt atom has oxidation stage (IV). The first Pt (IV) cytostatic was a complex called satraplatin, [bis(acetato-κO)amminedichloro(cyclohexanamine)-platinum (IV)], followed by the complex LA-12 (Matthew and Trevor, Reference Matthew and Trevor2002). These complexes have no side effects like previous complexes and they show even more effective cytotoxicity. The Pt complex LA-13 [amminedichloro(3,5-dimethyl-tricyclo[3.3.1.13,7]decan-1-amine)-platinum(II))] is the first intermediate in the whole synthesis of Pt complex LA-15, [bis(acetato-κO)amminedichloro (3,5-dimethyl tricyclo[3.3.1.13,7]decan-1-amine)-platinum (IV)], which is a structural analogue of the complex LA-12 as a potential cytostatic.
II. EXPERIMENTAL
A. Sample preparation
The preparation of the title compound is based on the synthesis of LA-12 described in the patent of Žák et al. (Reference Žák, Mistr, Poulová, Melka, Turánek and Záluská1999). The synthesis consists of the condensation of the Pt precursor called T-CAP (potassium amminetrichloroplatinate(II)) with the bulky amine ligand memantine (3,5-dimethyladamantane-1-amine). The memantine is then dissolved in methanol and the T-CAP is dissolved in DMF. Subsequently, one molar ratio of T-CAP was mixed with two molar ratios of memantine. The reaction was stirred and heated to 320 K for about 4 h. The product of synthesis (title compound, Figure 1) was filtrated and dried in a vacuum dryer.
Figure 1. Structural formula of the title amminedichloro(3.5-dimethyl-tricyclo[3.3.1.13.7]decan-1-amine)-platinum (IV) complex.
B. Diffraction data collection and reduction
The diffraction pattern for the title compound was collected at room temperature using an X'Pert PRO θ-θ powder diffractometer with parafocusing Bragg–Brentano geometry and Cu Kα 1 radiation (λ = 1.5406 Å, generator setting: 40 kV, 30 mA). An ultrafast X'Celerator detector was employed to collect X-ray diffraction (XRD) data over the angular range from 4° to 60°2θ with a step size of 0.017°2θ and a counting time of 20.32 s.step−1. The software package HighScore Plus V 3.0d of PANalytical, Almelo, Netherlands, was used to smooth the data, to fit the background and to eliminate the Kα 2 component. The top of smoothed peak method was used to determine the peak positions and intensities of the diffraction peaks.
Automatic indexing of the experimental XRD pattern was done using DICVOL04 (Boultif and Louër, Reference Boultif and Louër2004).
III. RESULTS
The experimental powder diffraction pattern is depicted in Figure 2. Automatic indexing results obtained by DICVOL04 (Table 1) show that the title compound is monoclinic with the space group P21/n and unit-cell parameters: a = 8.324(1) Å, b = 27.838(2) Å, c = 7.113(1), β = 111.25(1), unit-cell volume V = 1536.26 Å3, and Z = 4. The figures of merits are F 20 = 132.4(0.0044, 34) (Smith and Snyder, Reference Smith and Snyder1979) and M 20 = 48.4 (de Wolf, Reference De Wolff1968). All lines were indexed and are consistent with the P21/n space group.
Figure 2. (Color online) X-ray powder diffraction pattern of the title compound using and Cu Kα 1 radiation (λ = 1.5406 Å).
Table I. Indexed X-ray powder diffraction data for the title compound. C12H24Cl2N2Pt. Only the peaks with I rel of 1 or greater are presented [a = 8.324(1) Å, b = 27.838(2) Å, c = 7.113(1), β = 111.25(1), unit-cell volume V = 1536.26 Å3, Z = 4, and space group P21/n]. All measured lines were indexed and are consistent with the P21/n space group. The d-values were calculated using Cu Kα1 radiation (λ = 1.5406 Å).
SUPPLEMENTARY MATERIALS AND METHODS
To view supplementary material for this article, Please visit http://dx.doi.org/10.1017/S088571561500086
ACKNOWLEDGMENT
This work was supported by the “Operational Program Prague – Competitiveness” (CZ.2.16/3.1.00/22197) and the National Programme of Sustainability (NPU I MSMT – LO1215 and NPU I MSMT – LO1304).
