ABSTRACT
Reaction between the NH4VO3 and pyridoxal semicarbazone (PLSC) in a methanol/ammonia solution forms an orange, diamagnetic, mononuclear NH4[VO2(PLSC-2H)] complex in which vanadium is in the oxidation state +5, and pyridoxal semicarbazone is coordinated in its dianionic form. The complex cocrystallizes with a neutral molecule of PLSC and two water molecules. The coordination environment around vanadium can be described as an almost ideal square-pyramid. The complex was characterized by elemental analysis, conductometric and magnetochemical measurements, IR spectra, X-ray diffraction, and in vitro cytotoxicity analysis.
ABSTRACT
The title compound, dibromo(3-hydroxy-5-hydroxymethyl-2-methyl-4-pyridinecarboxaldehyde semicarbazone-kappa(3)N(1),O(3),O(3'))copper(II), [CuBr(2)(C(9)H(12)N(4)O(3))], consists of discrete complex units with the tridentate pyridoxal semicarbazone ligand as a zwitterion in an almost planar configuration. The Cu(II) ions are in a distorted square-pyramidal coordination, with the equatorial Br atom at a distance of 2.4017 (6) A and the apical Br atom at a distance of 2.6860 (6) A.
ABSTRACT
Part XLIII: Novakovic et al. (2002). The title complex, [Cu(NO(3))(C(10)H(14)N(4)O(2)S)(H(2)O)](NO(3)), is the first metal complex with a Schiff base derived from isothiosemicarbazide and pyridoxal (pyridoxal is 3-hydroxy-5-hydroxymethyl-2-methylpyridine-4-carboxaldehyde). The Cu(II) environment is a square pyramid, the equatorial plane of which is formed by the tridentate ONN-coordinated isothiosemicarbazone and one water molecule, while the nitrate ligand is in the apical position. The existence of numerous strong intermolecular hydrogen bonds, and weak C-H...O and C-H...pi interactions, leads to a three-dimensional supramolecular structure.
