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H[Vz03(pmida)z].4H20 (pmida = ((pyridy1methyl)imido)diacetate) crystallizes in the P2, space group with a = 10.672 (1) A, b = 12.22 (1) A, c = 10.495 (4) A, @ = 95.92 (4) A, and Z = 2. The structure has been solved to R = 0.056 for 1916 observed reflections. The [V203(pmida)z]-ion is almost centrosymmetric around the bridging oxygen atom. Small deviations to centrosymmetry are assigned to an asymmetric localization of the H+ ion rather than to valence trapping. The compound K7[V9OI6-(bdta)4].27H20 (bdta = butanediaminetetraacetate) crystallizes in the Pan2 space group with a = 25.34 (1) A, c = 17.09 (2) A, and Z = 4. The structure has been solved to R = 0.097 for 2289 observed reflections. It shows an unusual arrangement of four V-0-V mixed-valence pairs around a central V04 tetrahedron. Intervalence bands are observed near 10000 cm-' for the two complexes. However, in the case of [Vz03(pmida)2]-, a singlecrystal spectrum shows an additional band at 8300 cm-I with the expected polarization for an intervalence band. The magnetic behavior is consistent with the presence of a single unpaired electron in each mixed-valence unit, with very weak antiferromagnetic couplings. Finally, cyclic voltammetry of [V203(pmida)2]-in acetonitrile shows the existence of Vv-O-Vv and V'v-O-V'v dimers that decompose upon preparative electrolysis.

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Abstract1-(3-methyl-4H-1,4-benzothiazin-2-yl)ethanone (1,4-BT) was synthesised via a new mechanism. 1,4-BT was thereafter tested as corrosion inhibitor of mild steel in hydrochloric solution at 293 K by weight loss measurements and electrochemical techniques (potentiodynamic polarisation, polarisation resistance, impedance spectroscopy (EIS)). Inhibiting efficiency (E%) increased with concentration and reached highest values up to 98% even at low concentration with changing the mechanism of the corrosion process. Results obtained showed that the inhibitor studied was an efficient inhibitor, especially in cathodic domain. The temperature effect on the corrosion behaviour of mild steel in 1 M HCl with and without 1,4-BT at 5 10 -3 M was studied in the temperature range from 293 to 333 K. E% remains the same even at high temperature. The adsorption free energy and activation parameters for the mild steel dissolution reaction, in the presence of 1,4-BT, were determined. 1,4-BT is adsorbed on the mild steel surface according to a Langmuir isotherm adsorption model.

A series of nine polypyridyl-ruthenium (II) complexes (N-ligands ¼ 2,2 0 -bipyridines; 2,2 0 -6 0 ,2 0 -terpyridines, di-alkyloxy-2, 2 0 -6,2-bipyridine-3,3 0 -di-carboxylates), were tested against Mycobacterium tuberculosis (MBT). The complex (11) showed remarkable activity against MBT as compared to other complexes, (1-10). The aquo ligand of complex (11), as opposed to other chloro and acetonitrile derivatives, appears to play a key role in the antitubercular potency of this new class of metal-based compounds.