The series of complexes: cis-[Pd(PMSA)2X2], cis-[Pt(PMSA)2X2], trans-[Pt(PMSA)2I2] and [Pt(PMSA)4]Cl2 (PMSA = N-3-pyridinylmethanesulfonamide; X = Cl, Br, I), previously synthesized and characterized by us, as well as the free ligand PMSA, were tested for their cytotoxic activity without electroporation -- against murine leukemia F4N and human SKW-3 and MDA-MB-231 tumour cell lines -- and with ...

A photoactivatable Pt complex, trans,trans,trans[Pt(N3)2(OH)(succ)(py)2] (succ = succinylate, py = pyridine), has been conjugated to guanidinoneomycin to study the effect of this guanidinum-rich compound on the photoactivation, intracellular accumulation and phototoxicity of the pro-drug. Surprisingly, trifluoroacetic acid treatment causes the replacement of an azido ligand and the axial hydrox...

The octahedral Pt(IV) complex trans,trans,trans-[Pt(N(3))(2)(OH)(2)(py)(2)] (1) is potently cytotoxic to cancer cells when irradiated with visible (blue) light. We show that the acute photocytotoxicity can be switched off by low doses (500 μM) of the amino acid l-tryptophan. EPR and NMR spectroscopic experiments using spin traps show that l-Trp quenches the formation of azidyl radicals, probabl...

The 1.7 Å X-ray crystal structure of the B-DNA dodecamer, [d(CGCGAATTCGCG)]₂ (DDD)-bound non-covalently to a platinum(II) complex, [{Pt(NH₃)₃}₂-µ-{trans-Pt(NH₃)₂(NH₂(CH₂)₆NH₂)₂}](NO₃)₆ (1, TriplatinNC-A,) shows the trinuclear cation extended along the phosphate backbone and bridging the minor groove. The square planar tetra-am(m)ine Pt(II) units form bidentate N-O-N complexes with OP atoms, in ...

Although the genus Bordetella contains several closely related species, pertussis toxin (PT) is produced only by phase I Bordetella pertussis. In this work we have studied the regulation of expression of the PT operon and investigated why PT is produced by phase I and not by phase III B. pertussis despite the presence of the PT genes. We have constructed a vector for Bordetella species that con...

The synthesis and crystal and molecular structures of the platinum(II) complex Pt(HL)Cl where H(2)L is the diacid diamide -[CH(2)N(CH(2)COOH)CH(2)CONH(2)](2), a hydrolytic metabolite of an antitumour active bis(3,5-dioxopiperazin-1-yl)alkane are reported. The complex is square planar and contains HL(-) as a tridentate 2N (amino), O (carboxylate) donor. The metal to ligand bond distances are Pt-...

The novel dinuclear Pt(II) complexes [{trans-Pt(NH(3))(2)Cl}(2)(μ-pyrazine)](ClO(4))(2) (Pt1), [{trans-Pt(NH(3))(2)Cl}(2)(μ-4,4'-bipyridyl)](ClO(4))(2)·DMF (Pt2), and [{trans-Pt(NH(3))(2)Cl}(2)(μ-1,2-bis(4-pyridyl)ethane)](ClO(4))(2) (Pt3), were synthesized. Acid-base titrations, and temperature and concentration dependent kinetic measurements of the reactions with biologically relevant ligands...

Pt···Pt···Pt interactions via their d(8) orbitals, combined with π-π stacking of deprotonated, chelating 2-(3'-pyrazolyl)pyridine (pyzpy) ligands, are responsible for trans-Pt(pyzpy)(2) (2) crystallization in a stack of three molecules unsupported by any bridging ligand.

X-ray crystallographic analysis of the compound trans-[Pt(NH2C6H11)2I2] revealed the presence of two distinct conformers within one crystal lattice. This compound was studied by variable temperature NMR spectroscopy to investigate the dynamic interconversion between these isomers. The results of this investigation were interpreted using physical (CPK) and computational (molecular mechanics and ...