title: Synthesis, characterization and antioxidant activity of new copper(I) complexes of scorpionate and water soluble phosphane ligands.
abstract: New copper(I) complexes have been synthesised from the reaction of CuCl with potassium hydrotris(4-bromo-1H-pyrazol-1-yl)borate, KTp4Br or lithium bis(3,5-dimethylpyrazol-1-yl)acetate, Li[L2CO2] ligands and 4- or 2-(diphenylphosphane)benzoic acid or tris(m-sulfonatophenyl)posphine trisodium salt (TPPTS) coligands. The complexes obtained have been characterized by elemental analyses and FT-IR in the solid state, and by NMR (1H and 31P[1H]) and electrospray mass spectrometry (ESI-MS) in solution. Single crystal structural characterisation was undertaken for the [Cu[PPh2(4-C6H4COOH)](Tp4Br)] derivative, an interesting dimeric supramolecular assembly. A chemiluminescence study has demonstrated the superoxide scavenging activity of these new copper complexes. The Comet assay was used to evaluate the impairment of DNA in rat epithelial cells exposed to different reactive nitrogen species. In addition, the same complexes were included in this study to determine their efficacy as antioxidants in mitigating oxidative DNA damage. The parameter tail moment, used as an index of DNA damage, showed that the complex [Cu[PPh2(4-C6H4COOH)](Tp4Br)] remarkably inhibited DNA strand breaks induced by the different nitrogen oxide species. The other copper complexes under study showed a different ability to reduce tail moment values depending on the type of RNOS donor used.
authors.affiliation: Dipartimento di Scienze Chimiche Universitá di Camerino, MC, Italy.
authors.forename: Maura
authors.initials: M
authors.lastname: Pellei
authors.forename: Giancarlo Gioia
authors.initials: GG
authors.lastname: Lobbia
authors.forename: Carlo
authors.initials: C
authors.lastname: Santini
authors.forename: Riccardo
authors.initials: R
authors.lastname: Spagna
authors.forename: Mercedes
authors.initials: M
authors.lastname: Camalli
authors.forename: Donatella
authors.initials: D
authors.lastname: Fedeli
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Falcioni