27 research outputs found
Results of routine screening for sexually transmitted diseases in Austria over a six-year period.
Organometallic half-sandwich iridium anticancer complexes
The low-spin 5d6 IrIII organometallic half-sandwich complexes [(η5-Cpx)Ir(XY)Cl]0/+, Cpx = Cp*, tetramethyl(phenyl)cyclopentadienyl (Cpxph), or tetramethyl(biphenyl)cyclopentadienyl (Cpxbiph), XY = 1,10-phenanthroline (4â6), 2,2âČ-bipyridine (7â9), ethylenediamine (10 and 11), or picolinate (12â14), hydrolyze rapidly. Complexes with N,N-chelating ligands readily form adducts with 9-ethylguanine but not 9-ethyladenine; picolinate complexes bind to both purines. Cytotoxic potency toward A2780 human ovarian cancer cells increases with phenyl substitution on Cp*: Cpxbiph > Cpxph > Cp*; Cpxbiph complexes 6 and 9 have submicromolar activity. Guanine residues are preferential binding sites for 4â6 on plasmid DNA. Hydrophobicity (log P), cell and nucleus accumulation of Ir correlate with cytotoxicity, 6 > 5 > 4; they distribute similarly within cells. The ability to displace DNA intercalator ethidium bromide from DNA correlates with cytotoxicity and viscosity of IrâDNA adducts. The hydrophobicity and intercalative ability of Cpxph and Cpxbiph make a major contribution to the anticancer potency of their IrIII complexes