Palladium, platinum, cadmium, and mercury complexes with neutral isoorotic and 2-thioisoorotic acids: IR and NMR spectroscopies, thermal behavior and biological properties

Characterization of bis(isoorotato)diaquamagnesium(II) dihydrate: a potentially useful complex for magnesium supplementation

The synthesis and crystal structure of a new Mg(II) complex of stoichiometry [Mg(isoor)2(H2O)2].2H2O, where isoor is the monoanion of 5-carboxyuracil (isoorotic acid), are reported. The structure, solved by single-crystal X-ray diffractometry, shows that it crystallizes in the triclinic space group P(-1) with Z = 1. The electronic, IR and Raman spectra of the complex are briefly discussed. Its thermal behavior was also investigated by means of thermal gravimetry (TG) and differential thermal analysis (DTA) measurements in an oxygen atmosphere. Dissolution studies support the usefulness of the compound for magnesium supplementation.

Crystal structure, spectroscopic and magnetic studies, and antioxidative properties of catena-[diaqua(dihydro-orotato)manganese(II)]

The polynuclear manganese(II) complex of L-dihydroorotic acid has been synthesized and characterized by X-ray crystallography, UV-visible spectroscopy, and magnetic susceptibility measurements. Crystal data: triclinic, space group P1 bar , a = 4.7239(5) Å, b = 7.902(1) Å, c = 10.552(2) Å, α = 105.80(1)°, β = 98.864(7)°, γ = 104.69(1)°, V = 355.9(1) D 3, Z = 1, R = 0.035, Rw = 0.028. This complex consists of polymer chains of manganese atoms that are bound together via carboxylate bridges with a Mn...Mn distance in the chain of 4.724 D . The radical scavenging properties of the complex have been evaluated by ESR spectroscopy and cyclic voltammetry methods and compared to those of vitamin E and BHT (2,6-di-tert-butyl-4-methylphenol).Key words: orotic acid, L-dihydroorotic acid, manganese(II) complex, antioxidative properties.

Zinc, cadmium, and mercury complexes of 5,7-dimethyl-[1,2,4]triazolo[1,5-a]pyrimidine (dmtp). Preparation, spectroscopic characterization, and biological activity. X-ray crystal structures of [Zn(dmtp)2Br2], [Hg(dmtp)2Cl2], and [Hdmtp]2[CdBr4]. 2H2O

The preparation and spectroscopic characterization of a series of dmtp complexes of Zn, Cd, and Hg, where dmtp is 5,7-dimethyl[1,2,4]triazolo[1,5-a]pyrimidine, is reported. Crystal structure analyses of [Zn(dmtp)2Br2] and [Hg(dmtp)2Cl2] reveal distorted tetrahedral geometries about the central atoms and the dmtp ligands to coordinate via the N(3) atom exclusively. In the X-ray structure of [Hdmtp]2[CdBr4].2H2O, the [Hdmtp]+ cation is protonated at the N(3) atom, there being no significant interaction between Hdmtp and cadmium. A study of the antimicrobial activity of the complexes shows that the [Cd(dmtp)X2(OH2)] (X = Cl, Br) compounds display activity against two strains.