In vitro exposure of the TR170 ovarian carcinoma cell line to six intermittent 24-h treatments with a 90% inhibitory concentration of cisplatin (CDDP) (0.15 micrograms/ml; 0.5 microM) resulted in a 2-fold stably resistant subline designated TR170/CP+ (B.T. Hill et al., Int. J. Cancer, 39: 219-225, 1987). Resistance to CDDP in these CP+ cells has now been associated with reduced uptake of 195mCD...

A novel bimetallic conjugate combining a rhodium intercalator that selectively binds DNA mismatches and a reactive cis-platinum analogue that targets DNA by coordination has been prepared. The site-selectivity of the bimetallic complex in forming coordination adducts is examined using mismatched and well-matched oligonucleotides of different sequences. The results indicate that through the bifu...

Single crystals of cis-[Pt(NO2)2(NH3)2], were obtained by means of hyper-saturation directly out of a plating electrolyte. The square-planar coordination environment of the divalent Pt(II) atom is formed by four N atoms belonging to two ammine and two monodentate nitrite ligands. The ligands adopt a cis configuration. The crystal structure contains stacks of close-packed mol-ecules which run pa...

A series of transition-metal-containing molecular "loops" and "squares" has been prepared via a directed-assembly approach and characterized. The molecular loops were prepared from the reaction of cis-(PEt(3))(2)Pt(OTf)(2) with bis(4-pyridyl)-functionalized free-base salen-type ligands. Zn(II)-metalation of the salen-type ligands in the molecular loops converts the loops to molecular squares. A...

Single crystals of cis-[Pt(NO2)2(NH3)2], were obtained by means of hypersaturation directly out of a plating electrolyte. The square-planar coordination environment of the divalent Pt atom is formed by four N atoms belonging to two ammine and two monodentate nitrite ligands. The ligands adopt a cis configuration. The crystal structure contains stacks of close-packed molecules which run parallel...

A new donor-acceptor system, in which the electron donor triphenylamine (TPA) and the electron acceptor C60 are bridged through a cis- or trans-platinum(II) acetylide spacer have been prepared. Ground-state studies were conducted using electrochemistry and UV/Vis spectroscopy. Fluorescence studies suggested that charge transfer is the deactivation mechanism for the singlet excited state, and th...

Cis-(Ph3P)2PtCl2 and cis-(Ph3P)2PtCO3 were prepared mechanochemically from solid reactants in the absence of a solvent; cis-(Ph3P)2PtCl2 was obtained in 98% yield after ball-milling of polycrystalline PtCl2 and Ph3P; the mechanically induced solid-state reaction of cis-(Ph3P)2PtCl2 with an excess of anhydrous K2CO3 produced cis-(Ph3P)2PtCO3 in 70% yield; the formation of transition metal comple...

The kinetics of the reactions of 5'-AMP and 5'-GMP with excess cis-[Pt(NH,),CI,] in the presence of KCI at pH* 6.5 have been investigated by 'H NMR and analyzed by nonlinear numerical integration and optimization techniques. The species formed have been further characterized by 195Pt NMR. The reaction with 5'-AMP involves a branching pathway: 5'-AMP reacts with ~ i s [ P t ( N H ~ ) ~ c l , ] t...

The synthesis and molecular structure of a monomeric diplatinum(II) complex composed of mono-lacunary α-Keggin polyoxometalate is described. The polyoxometalate, Cs(3)[α-PW(11)O(39){cis-Pt(NH(3))(2)}(2)]·8H(2)O (Cs-1), afforded by a stoichiometric reaction of mono-lacunary Keggin polyoxotungstate with cis-diamminedichloroplatinum(ii) in water, followed by crystallization from water, was obtaine...

In the title complex, [Pt(NCS)(2)(C(8)H(6)N(4))], the Pt(II) ion is four-coordinated in a distorted square-planar environment defined by two pyrimidine N atoms derived from a chelating 2,2'-bipyrimidine (bpym) ligand and two mutually cis N atoms from two SCN(-) anions. The thio-cyanate ligands are almost linear, displaying N-C-S bond angles of 178.6 (11) and 173.7 (11)°, and the N atoms are sli...