Z. Naturforsch. 54 b, 209-213 (1999); received September 9, 1998 Phosphinine Complex, Platinum, X-Ray Data, NMR Data, frans-Influence C/5-Dichloro-bis(2 ,6 -dimethyl-4 -phenyl-77'-phosphinine)platinum (3) has been prepared by ligand substitution from cis -dichloro(2,5-cyclooctadiene)platinum and characterized by spec­ troscopy ('H , 13C, 31P NMR, IR, UV-Vis), CV and X-ray diffraction (space gro...

The reaction of cis-Pt(NH3)2Cl2(cis-DDP)-closed circular DNA adducts with DNA topoisomerse I(topo I) were studied by electron microscopy. We identified unique topoisomers such as a singly-linked catenane (2(1)2), trefoil (3(1), and dimetric catenane (2(1)2), etc., by analysis with electron micrographs. These unique recombination products resulted from cis-DDP-intra-twisting looped DNA adducts b...

The thermal denaturation profiles of Calf Thymus DNA in the presence of binuclear compounds of bivalent platinum (cis-[{Pt(NH3)2Cl}2Pyr]Cl2) were studied by absorption spectrophotometry and differential adiabatic scanning microcalorimetry. A comparison with an active antitumor drug cis-diamminedichloroplatinum (cis-DDP) was made. Experimental data witness that small concentrations (r<0.3) of bi...

Various Pt(IV) diazides have been investigated over the years as light-activatable prodrugs that interfere with cell proliferation, accumulate in cancer cells and cause cell death. The potencies of the complexes vary depending on the substituted amines (pyridine=piperidine>ammine) as well as the coordination geometry (trans diazide>cis). Light-activated Pt(IV) diazides tend to be less specific ...

The reaction of [Pt(en)(H(2)O)(2)](2+) with 1 equivalent of 1-methylcytosine at an initial pH of 6 ultimately led to the 1-methylcytosinato-bridged (ethylenediamine)platinum(II) dimer, [(en)Pt(MetCyt-H)(2)Pt(en)](NO(3))(2) (1). The species during the reactions prior to formation of 1 have been investigated by using (195)Pt NMR spectroscopy. From the reaction mixture the [Pt(en)(MetCyt)(2)](NO(3...

Development of drug resistance and the presence of dose-limiting side-effects remain two major problems in cancer chemotherapy. Combination of drugs can offer a means of overcoming drug resistance and reducing side-effects. This study investigated synergism in activity from the combinations of cisplatin (Cis) and trans-planaramineplatinum(II) compound YH12 in the human ovarian A2780, A2780(cisR...

Platinum pyrimidine "blues," a class of potent antitumor drugs [1] derived from cw-dichlorodiammineplatinum(II) (a's-PDD) or the corresponding hydrolysis product as-diaquodiammineplatinum(II) (cis-PDDa), have lately been the subject of considerable research effort in order to elucidate their structure and mode of action. The structure of platinum a-pyridone "blue," a Pt pyridine complex in some...

The asymmetric unit of the title compound, [PtCl(2)(C(6)H(4)NO(2))(2)]·CH(3)CN, contains a neutral Pt(IV) complex and an acetonitrile solvent mol-ecule. In the complex, the Pt(4+) atom is six-coordinated in a distorted octa-hedral environment by two N atoms and two O atoms from two pyridine-carboxyl-ate (pic) ligands and two Cl atoms. The Cl atoms are cis with respect to each other. The compoun...

The first base-stabilized iodoborylene platinum complex was prepared through the addition of 4-picoline (4-Pic) to a suspension of an iodo-bridged binuclear iodoboryl complex. An X-ray structure determination of the title compound has characterized the molecular structure as cis-[Pt{BI(4Pic)}I2(PCy3)]. The bond lengths lie in the expected range for neutral, base-stabilized borylene complexes. T...