Synthesis, crystal structure, characterization of zinc(II), cadmium(II) complexes with 3-thiophene aldehyde thiosemicarbazone (3TTSCH). Biological activities of 3TTSCH and its complexes.

The reaction of zinc(II) chloride, cadmium(II) chloride and bromide with 3-thiophene aldehyde thiosemicarbazone leads to the formation of a series of new complexes. They have been characterized by spectroscopic studies: infrared, (1)H NMR, and electronic spectra. The crystal structures of the compound [ZnCl(2)(3TTSCH)(2)] and [CdBr(2)(3TTSCH)(2)] have been determined by X-ray diffraction methods. For the complexes [ZnCl(2)(3TTSCH)(2)] and [CdBr(2)(3TTSCH)(2)], the central ion is coordinated through the sulfur, and for the complexes [CdCl(2)(3TTSCH)], [CdBr(2)(3TTSCH)] the ion is coordinated through the sulfur as well as azomethine nitrogen atom of the thiosemicarbazone. In addition, fungistatic and bacteriostatic activities of both ligand and complexes have been evaluated. Cadmium(II) complexes have shown the most significant activities.

Zwitterionic 6-methyl-2-oxo-3-[1-(ureido-iminio)eth-yl]-2H-pyran-4-olate monohydrate.

The title compound, C(9)H(11)N(3)O(4)·H(2)O, was prepared by the reaction of dehydro-acetic acid and semicarbazide hydro-chloride. It crystallizes in a zwitterionic form with cationic iminium and anionic enolate groups. In the crystal structure, the almost planar mol-ecules are held together by N-H⋯O, O-H⋯O and C-H⋯O hydrogen bonds, some of them involving the water molecules.

In vitro and in vivo effects of [Ni(M5FTSC)2Cl2] complex in cancer: preliminary tests.

The human colon adenocarcinoma-derived cell line CaCo-2 male Swiss mice and male Sprague-Dawley rats were used as model systems to study the effects of nickel (II), 5-methyl-2-furaldehyde thiosemicarbazone ligand and their complex. The stimulation effect of the complex was obtained with low concentrations from 3.7 x 10(-7) to 3.7 x 10(-6) M, while inhibiting effects occurred from 3.7 x 10(-5) to 3.7 x 10(-4) M. This study showed that Ni (II) is toxic for cultured cells. Our data suggest that the comple; according to the toxicity assays in mice and carcinogenesis assays in rats, could be used as an antimitotic agent.

Solvent effects on the stability of nifuroxazide complexes with cobalt(II), nickel(II) and copper(II) in alcohols.

A spectrophotometric study of the complexation of nifuroxazide with cobalt(II), nickel(II) and copper(II) was carried out in different alcohols. The formation of a complex in each case is reported and their stability constants have been calculated. For a given solvent, the stability of the complexes increases from cobalt to copper. In the case of copper(II), the stability varies as an inverse function of the dielectric constant of the solvent. A possible structure of the complex is proposed.

A comparison of the acidity and the complexing ability of (o-hydroxyphenyl) bis- and (o-hydroxyphenyl) mono-methylenephosphonic acids towards lanthanide(III) ions.

The characterization of the acid-base properties of a family of three phenoldimethylenephosphonic acids differently substituted by auxo- or chromophoric groups was studied. These ligands may be considered as pentaacids. Their pK(a) were determined in aqueous solution at 25 degrees C and constant ionic strength 0.1 mol dm(-3) by potentiometry and UV-visible spectrophotometry. Eventually, the complexing power of these molecules with lanthanide cations, Ce(3+), Pr(3+), Nd(3+), Sm(3+) and Eu(3+), was studied keeping in view the possible application to the treatment of radioactive liquid waste. The number, the nature of the species in solution, their stability constants and their individual electronic spectra as restored by computation have been determined. In all cases, complexes of 1:1 stoichiometry accompanied by hydroxy and protonated species are postulated. The comparison of tri- and pentaacids confirms that the acids having the methyl group at the para position with respect to the phenolic OH, have the highest complexing power.