Showing papers by "Carlo Santini published in 2004"
TL;DR: The parameter tail moment showed that the complex [Cu[PPh2(4-C6H4COOH)](Tp4Br)] remarkably inhibited DNA strand breaks induced by the different nitrogen oxide species, and the other copper complexes under study showed a different ability to reduce tail moment values depending on the type of RNOS donor used.
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.
51 citations
TL;DR: A comprehensive survey of the syntheses and of spectroscopic, analytical and structural data of silver(I), copper(I, and copper(II) complexes containing scorpionate and related ligands and prepared by this group has been reported as discussed by the authors.
50 citations
TL;DR: In this article, the authors showed that the tetrahedral coordination geometry of the silver atom adopts a distorted tetrasquare coordination geometry and showed that it is possible to obtain the existence of dimeric species of the form [Ag2(L)(PiBu3)2] and [Ag(TpCF3] using a mixture of Ag(L) and PiBu3.
24 citations
TL;DR: Gold derivatives and a number of Cu, Ag and Au complexes containing scorpionate ligands have been investigated by 31P cross-polarization magic-angle-spinning (CPMAS) NMR spectroscopy and suggest greater stability of the tetrakis(pyrazolyl)borate relative to those of tris( Pythonrazol-1-yl)borates.
Abstract: Gold derivatives [Au(Tpx)(PR3)]
(Tpx
= Tp, hydrotris(pyrazol-1-yl)borate or Tp*, hydrotris(3,5-dimethylpyrazol-1-yl)borate; R = Ph or tBu) and [Au(pzTp)(PR3)x]
(pzTp = tetrakis(pyrazol-1-yl)borate, x
= 1 or 2, R = Ph or tBu) have been synthesised and characterized both in solution (1H- and 31P{1H}-NMR) and in the solid state (IR, single crystal X-ray structure analysis, 31P CPMAS). 31P {1H} NMR solution data suggest greater stability of the tetrakis(pyrazolyl)borate relative to those of tris(pyrazolyl)borate. All compounds are fluxional at room temperature. In order to compare [Au(Tp*)(PPh3)] with analogous coinage metal adducts we have synthesized and structurally characterized [Cu(Tp*)(PPh3)]·PPh3 and [Ag(Tp*)(PPh3)]·2MeCN. In [Au(Tp*)(PPh3)] the gold atom adopts a distorted tetrahedral geometry with 2.181(5) and 2.37(2)
A
(cf. 2.166(6), 2.098(1) in [Cu(Tp*)PPh3], 2.156(2), 2.075(7) in [Cu(Tp*)(PPh3)]·PPh3; and in [Ag(Tp*)PPh3]·MeCN 2.347(12), 2.35(5)
A). There are three independent [Au(Tp*)(PPh3)] molecules in the asymmetric unit of the structure with their PAu⋯B axes lying on the cell diagonal of a cubic P213 cell, two with the same chirality aligned opposed in direction to the third which is of opposite chirality. A number of Cu, Ag and Au complexes containing scorpionate ligands have also been investigated by 31P cross-polarization magic-angle-spinning (CPMAS) NMR spectroscopy.
22 citations
TL;DR: In this paper, new copper(I) complexes have been synthesized from the reaction of CuCl with 4- or 2-(diphenylphosphane)benzoic acid and KH 2 B(im) 2 (dmac), which have been characterized by elemental analyses and FT-IR in the solid state, and by NMR ( 1 H and 31 P{ 1 H}) and electrospray mass spectroscopy in solution.
19 citations
TL;DR: In this article, the CH 2 (Pz COOH,Me ) 2 ligand reacts with ZnAc 2 and CdCl 2 in the presence of two equivalents of NaOH, to yield the {M[CH 2(PzCOOH-Me 2 ]·n H 2 O} (M=Zn(II), n =2; M=Cd(II, n =1) complexes.
8 citations
TL;DR: In this article, the new dihydrobis(3-carboxyethyl-5-methylpyrazolyl)borate ligand BpCOOET,Me is prepared as its potassium salt in kerosene solution, using ethyl 3-methyl pyrazole-5 carboxylate and KBH4, through careful temperature control.
7 citations
TL;DR: A comprehensive survey of the syntheses and of spectroscopic, analytical and structural data of silver(I), copper(I, and copper(II) complexes containing scorpionate and related ligands and prepared by this group has been reported as discussed by the authors.
Abstract: A comprehensive survey of the syntheses and of spectroscopic, analytical and structural data of silver(I), copper(I), and copper(II) complexes containing scorpionate and related ligands and prepared by this group has been reported. This review outlines the possible strategies that can be used in this field for the synthesis of analogous complexes. Statistical analyses of structural features are reported as a function of (1) the steric and electronic properties of the scorpionate ligand, (2) the steric and electronic properties of eventual ancillary ligands, and (3) the nature of the counter-ion. The most important results obtained in this field have been also summarized.
3 citations