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[RuCl3 center dot nH(2)O] and Na(trans-[RuCl4(DMSO)(2)])D were reacted with 1-pyrrolidinedithiocarbamate (PDT). its S-rnethyl ester (PDTM), and N,N-dimethylcarbamodithioic acid methyl ester (DMDTM) in water or methanol in order to obtain the corresponding Ru(III) derivatives. Once isolated and purified, the complexes were characterized by means of elemental analysis, conductivity measurements, FT-IR and H-1 NMR spectroscopy, ion electrospray mass spectrometry (ESI-MS), and thermal analyses. The crystal structure of mer-[Ru(DMDTM)(DMSO)Cl-3] has been also determined by X-ray crystallography. In vitro cytotoxic activity of all the synthesized complexes was eventually evaluated on some selected human tumor cell lines.

The compartmental [1+1] macrocycle H3L, obtained by self-condensation of the formyl precursor 3,3'-(3,6-dioxaoctane-1,8-diyldioxy)bis(2-hydroxybenzaldehyde) with the amine precursor N,N-bis(2-aminoethyl)-2-hydroxybenzylamine, contains one inner ON3O2 Schiff base and one outer O2O4 crown-like chamber. According to the experimental conditions it forms, by a template process, the stable mononuclear complexes Ln(H3L)(Cl)(2)(CH3COO)center dot nS center dot mHCl or [Ln(L)center dot nS (Ln = La, Lu, Y, Yb, Er, Dy, Tb, Gd, Eu, Ce) with the lanthanide(III) ion encapsulated in the crown - ether-like and in the Schiff base site. The mononuclear complexes Ln(H3L)(Cl)(2)-(CH3COO)center dot nS center dot mHCl, by further complexation with a different lanthanide(III) ion, give rise to the related heterodinuclear complexes [LnLn'(L)(Cl)(2)(CH3COO)center dot nS while the homodinuclear and the heterodinuclear complexes [Ln(2)(L)](Cl)(3)center dot nH(2)O and [LnLn'(L)](Cl)(3)center dot nS could be prepared by a template reaction using the appropriate molar ratio of reactants. Their properties have been studied by using SEM-EDS microscopy, IR and NMR spectroscopy and their compositions confirmed by thermal and ESI-Mass spectrometric analyses. In the heterodinuclear complexes, the site occupancy of the different lanthanide(III) ions was determined by H-1 and C-13 NMR spectioscopy in CD3OD or (CD3)(2)SO - it was found that heterodinuclear complexation occurs in methanol with the smaller lanthanide(III) ion mainly coordinating to the Schiff base site and the larger lanthanide(Ill) ion to the crown site whereas, in dimethyl sulfoxide, demetalation of the weaker coordinated lanthanide(III) ion into the crown ether chamber occurs with the subsequent formation of mononuclear species in solution. The thermal decomposition of the heterodinuclear complexes forms the related mixed oxides, the stoichiometries and properties of which were determined by SEM-EDS microscopy and X-ray powder diffraction studies (XRD).

In the last years, we have synthesized some new platinum(II), palladium(II), gold(I/III) complexes with dithiocarbamato derivatives as potential anticancer drugs, to obtain compounds with superior chemotherapeutic index in terms of increased bioavailability, higher cytotoxicity, and lower side effects than cisplatin. On the basis of the obtained encouraging results, we have been studying the interaction of CuCl2 with methyl-/ethyl-/tert-butylsarcosinedithiocarbamato moieties in a 1:2 molar ratio; we also synthesized and studied the N,N-dimethyl- and pyrrolidinedithiocarbamato copper complexes for comparison purposes. The reported compounds have been successfully isolated, purified, and fully characterized by means of several spectroscopic techniques. Moreover, the electrochemical properties of the designed compounds have been studied through cyclic voltammetry. In addition, the behavior in solution was followed by means of UV-vis technique to check the stability with time in physiological conditions. To evaluate their in vitro cytotoxic properties, preliminary biological assays (MTT test) have been carried out on a panel of human tumor cell lines. The results show that cytotoxicity levels of all of the tested complexes are comparable or even greater than that of the reference drug (cisplatin).

The dithioester (CH2)4NCS2CH3 (PyDTM, 1-pyrrolidinecarbodithioate methyl ester) has been prepared by reaction of the parent ammonium salt NH4PyDT (PyDT=(CH2)4NCS2 with methyl iodide in water/ethanol. The reaction of PyDTM with PdCl2 allowed to synthesize either (PdCl2(PyDTM)), in which the ligand is chelated by both sulfur atoms, or(PdCl2(PyDTM)2), in which the ligand acts as monodentate through the thiocarbonyl sulfur. Thermal degradation of(PdCl2(PyDTM)), yielded the (PdCl2(PyDTM))n species as an intermediate, which, in the presence of donors as chloride ions or dimethyl sulfoxide (DMSO), gave the complexes [PdCl(PyDT)(DMSO)] and NR4(PdCl2(PyDT)). Moreover, PyDTM was found to react with various [PdCl(dithiocarbamato)]n intermediates to form the mixed species [PdCl(dithiocarbamato)(PyDTM)], whose thermal degradation yielded the [Pd(dithiocarbamato)(PyDT)] complexes. The behaviour of the prepared compounds in either solution or solid phase has been described on the basis of IR and proton NMR spectra and thermogravimetric analysis (TG and DTA).

The syntesis and the caracterization of some bis-cyclopentadienyl hafnium derivatives were realized. Hafnium (IV) compounds were identified by NMR spectroscopy, thermogravimetric measurements and mass spectrometry methods. The temperature dependencies of saturated vapor pressure were obtained using Knudsen method. Thermodynamic parameters of sublimation processeswere calculated. Thermal decomposition processes in vacuum and in an oxigen atmosphere were studied by high temperature mass spectrometry and gas by-products were determined, The volatile Cp2Hf(NEt2)2 and Cp2HfMe2 precursors were used for the Hafnium oxide films deposition using the MOCVD tecnique. The films were characterized by X-ray diffraction and IR-spectroscopy methods. X-ray diffraction patterns show the formation of monoclinic HfO2 phase.

This work reports on the synthesis, characterization and in vitro cytotoxic activity of some new platinum(II), palladium(II) and gold(III) derivatives of methylsarcosinedithiocarbamate and its S-methyl ester, in order to study their behavior as potential antitumor agents. The biological activity of these compounds, as determined by growth inhibition and apoptosis induction, has been investigated in both human leukemic promyelocites HL60 and human squamous cervical adenocarcinoma HeLa cell lines, and their activity compared to the well known platinum-based anticancer agent cisplatin. On the basis of these experimental results, ƒËPd(MSDT)XƒÍn (MSDT = methylsarcosinedithiocarbamate; X = Cl, Br) complexes determine a strong dose-dependent growth inhibition of both HL60 and HeLa cells, with IC50 values slightly higher than those recorded for cisplatin; moreover, ƒËAu(MSDT)X2] activity appears significantly higher or, at least, comparable to that of the reference drug. Exposure of both cell lines to ƒËPd(MSDT)XƒÍn and ƒËAu(MSDT)X2] complexes induces apoptosis, as determined by Apo2.7 assay.

This work reports on the synthesis, characterization and biological activity of new coordination compounds of the type [M(TSDTM)X(2)] (M=Pt(II), Pd(II); X=Cl, Br; TSDTM=ter-butylsarcosine(S-methyl)dithiocarbamate) and [Pd(TSDT)X](n) (TSDT=ter-butylsarcosinedithiocarbamate) in order to study their behavior as potential antitumor agents. All the synthesized compounds were characterized by means of elemental analysis, FT-IR, (1)H and (13)C-NMR spectroscopy and thermogravimetric analysis, suggesting a chelate S,S' structure of the TSDTM/TSDT ligand in a square-planar geometry. Finally, the synthesized complexes have been tested for in vitro cytotoxic activity against human leukemic HL60 and adenocarcinoma HeLa cells; the most active compound [Pt(TSDTM)Br(2)], characterized by IC(50) values very similar to those of the reference compound (cisplatin), was also tested for in vitro nephrotoxicity showing a very low renal cytotoxicity as compared to cisplatin itself.

The [M(dithiocarbamato)(Mol)]Cl complexes [M = Pd or Pt; dithiocarbamato = DMDT (Me2NCS2-) or ESDT (EtO2CCH2MeNCS2-); Mol = L-methioninol (L-2- amino-4-methylthio-1-butanol)] have been prepared by reacting methioninol with the appropriate [M(dithiocarbamato)Cl]n complex at 1 : 1 molar ratio in chlorinated hydrocarbons. By operating at 1 : 2 molar ratio, the binuclear species [M2(dithiocarbamato)2(Mol)Cl2] were obtained. The complexes were characterized by i.r., n.m.r. and electrospray ionisation (ESI) mass spectra and by t.g.a. The [M(dithiocarbamato)(Mol)]Cl species are ionic and contain S,N chelated methioninol. The ligand forms a S,N bridge between two metal atoms in the binuclear species, whose formation is confirmed by the presence of the deprotonated molecular ion in the ESI negative ion mode.