We have synthesized and crystallized a cytosine-decavanadate compound, Na(3) [V(10)O(28)] (C(4)N(3)OH(5))(3)(C(4)N(3)OH(6))(3).10H(2)O, and its crystal structure has been determined from a single-crystal X-ray diffraction. A high resolution X-ray diffraction experiment at 210 K (in P1 space group phase) was carried out. The data were refined using a pseudo-atom multipole model to get the electron density and the electrostatic properties of the decavanadate-cytosine complex. Static deformation density maps and Atoms in Molecules (AIM) topological analysis were used for this purpose. To get insight into the reactivity of the decavanadate anion, we have determined the atomic net charges and the molecular electrostatic potential. Special attention was paid to the hydrogen bonding occurring in the solid state between the decavanadate anion and its environment. The comparison of the experimental electronic characteristics of the decavanadate anions to those found in literature reveals that this anion is a rigid entity conserving its intrinsic properties. This is of particular importance for the future investigations of the biological activities of the decavanadate anion.

We have retrieved from the Cambridge Structural Database (CSD), the Inorganic Crystal Structure Database (ICSD) and the Protein Data Bank (PDB) decavanadate based compounds, in order to find intermolecular interactions between decavanadate oxygen atom and different proton donor type (D = O, N, C). 63 different structures have been found containing decavanadate anion, leading to 2975 intermolecular contacts belonging to the 48 structures for which the hydrogen bonds have been localised. In a previous study, (Bosnjakovic-Pavlovic et al., Inorg. Chem., 2009) we have predicted the preferential noncovalent interactions with the different oxygen atoms of the decavanadate anion. These predictions are confirmed, in the present study. Noncovalent interactions are strongly different as a function of the oxygen atom type. The Ob, triply-linked, and Oc, double-linked oxygen atoms, for which the electrostatic potential in the vicinity have the lowest value, are mainly involved in the strong as O-H⋅⋅⋅O, N-H⋅⋅⋅O interactions, while the mono linked Of or Og are mainly involved in weakest noncovalent interactions such as C-H⋅⋅⋅O or cation interactions. Binding properties of decavanadate anion in biological systems are illustrated using PDB. Anion binding behaviour in small-molecule structures and in macromolecular structures is in good agreement. These results are important in the context of the various biological applications of the decavanadate such as, for example, inhibition of the Ca 2+ ATPase, myosin ATPase, and new development in insulin mimetic.