N,N′-bis[(3-hydroxy-4(4H)-oxypyran-2-yl)methyl]-N,N′-dimethylethylene-1,2-diammonium tetrachloridoplatinate(II) dihydrate

The title compound (C16H22N2O6)[PtCl4]·2H2O, shows antiproliferative activity in eight tumor cell lines. The asymmetric unit consists of one solvent water molecule on a general position, and one half of each of the polyammonium cation and the tetrachloridoplatinate(II) anion, both of them located on centers of inversion. In the crystal, the cations are connected via hydrogen bonding between the carbonyl O atoms and the hydroxyl H atoms into zigzag chains that elongate in the c-axis direction. In addition, the carbonyl O atom is hydrogen-bonded to the water molecule which, in turn, interacts with the [PtCl4]2− anion. Finally, the chains are linked by N—H+⋯Cl interactions into a three-dimensional network.

The title compound (C 16 H 22 N 2 O 6 ) [PtCl 4 ]Á2H 2 O, shows antiproliferative activity in eight tumor cell lines. The asymmetric unit consists of one solvent water molecule on a general position, and one half of each of the polyammonium cation and the tetrachloridoplatinate(II) anion, both of them located on centers of inversion. In the crystal, the cations are connected via hydrogen bonding between the carbonyl O atoms and the hydroxyl H atoms into zigzag chains that elongate in the c-axis direction. In addition, the carbonyl O atom is hydrogen-bonded to the water molecule which, in turn, interacts with the [PtCl 4 ] 2À anion. Finally, the chains are linked by N-H + Á Á ÁCl interactions into a three-dimensional network.

Experimental
Malten . 2HClO 4 was dissolved in H 2 O, K 2 PtCl 4 was added and the pH adjusted to 3. Crystals suitable for X-ray analysis formed in one day at room temperature.

Refinement
The O-H and N-H H atoms were located in the Fourier difference map and refined with varying coordinates isotropic.
The C-H H atoms were introduced in calculated position and refined isotropic with U iso (H) 1.2 times U eq (C) (1.5 for methyl H atoms).  Crystal structure of the title compound with labelling and displacement ellipsoids drawn at the 30% probability level.

Figure 2
Crystal structure of the title compound with view along the a axis. Intermolecular hydrogen bonding is shown as dashed lines.

tetrachloridoplatinate(II) dihydrate
Crystal data (C 16  where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 1.44 e Å −3 Δρ min = −1.14 e Å −3 Special details Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > 2σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.