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The decomposition of quinalphos, O,O‐diethyl O‐quinoxalin‐2‐yl phosphorothioate, on homoionic Cu(II)‐, Fe(III)‐, Al‐, Na‐, K‐ and Cabentonites in hydroalcoholic solution has been investigated. The results show that the hydrolysis of the pesticide may involve two different mechanisms, both depending on the nature of the exchangeable cations. The pesticide hydrolyses to 2‐hydroxyquinoxaline on the Cu‐, Fe‐ and Al‐clays, whereas O‐ethyl O‐quinoxalin‐2‐yl thiophosphoric acid is the main product of hydrolysis on the Na‐, K‐ and Ca‐clays. The de‐ethylation reaction appears to be favoured by the hydrolysis of the Na‐and K‐clays. A bidentate complex formed by quinalphos and the interlayer exchangeable cations may be responsible for the formation of 2‐hydroxyquinoxaline. The presence of this product in the interlamellar region of clay was shown by infrared and X‐ray data.

Metal ions play key roles in biology. Many are essential for catalysis, for electron transfer and for the fixation, sensing, and metabolism of gases. Others compete with those essential metal ions or have toxic or pharmacological effects. This book is structured around the periodic table and focuses on the control of metal ions in cells. It addresses the molecular aspects of binding, transport and storage that ensure balanced levels of the essential elements. Organisms have also developed mechanisms to deal with the non-essential metal ions. However, through new uses and manufacturing processes, organisms are increasingly exposed to changing levels of both essential and non-essential ions in new chemical forms. They may not have developed defenses against some of these forms (such as nanoparticles). Many diseases such as cancer, diabetes and neurodegeneration are associated with metal ion imbalance. There may be a deficiency of the essential metals, overload of either essential or non-essential metals or perturbation of the overall natural balance. This book is the first to comprehensively survey the molecular nature of the overall natural balance of metal ions in nutrition, toxicology and pharmacology. It is written as an introduction to research for students and researchers in academia and industry and begins with a chapter by Professor R J P Williams FRS.

Nickel (II), Carbacylamidophosphates, X-Ray DataA new nickel(II) complex with N,N'-tetraethyl-N"-benzoylphosphortriamide (HL = C6H5C(0 )N(H)P(0 )(NEt2)2) of composition Ni4L4(OCH3)4-(HOCH;04 (1) has been synthe sized. The crystal and molecular structure of 1 has been determined from the X-Ray diffraction data (tetragonal, space group P42)C with a = 17.000(2) A, c = 15.338(3) A, Z = 2; R = 0.0399 for 1412 unique reflections). The structure is made up of cubane-like tetramers. In the corners of a cube there are 4 atoms of nickel and 4 atoms of oxygen of methoxy groups. The nickel atoms are characterized by a slightly distorted octahedral environment, which consists of three oxygen atoms of methoxy groups, carbonylic and phosphorylic oxygen atoms of the ligand L~, and an oxygen atom of a methanol molecule. The ligands L~ coordinate to the metal ion forming a chelate via the oxygen atoms of carbonylic and phosphorylic groups.

Bis(1H-pyrazol-4-yl)selenides. -The reaction in refluxing pyridine offers a direct access to the target compounds. The unsubstituted imidazole (III) gives a trispyrazolyl selenonium compound after ethanolic work-up. -(SEREDYUK, M.; FRITSKY*, I. O.; KRAEMER, R.; KOZLOWSKI, H.; HAUKKA, M.; GUETLICH, P.; Tetrahedron 66 (2010) 45, 8772-8777, http://dx.doi.org/10.1016/j.tet.2010.08.071 ; Dep. Chem., Taras Shevchenko Natl. Univ., Kiev 01601, Ukraine; Eng.) -Mais 10-185