Találati lista | Tudóstér

001-es BibID:	BIBFORM056651
Első szerző:	Jakusch Tamás
Cím:	Vanadate complexes of 3-hydroxy-1,2-dimethyl-pyridinone : speciation, structure and redox properties / Tamás Jakusch, Éva A. Enyedy, Károly Kozma, Zsófia Paár, Attila Bényei, Tamás Kiss
Dátum:	2014
ISSN:	0020-1693
Megjegyzések:	Several articles were published about the vanadate?3-hydroxy-1,2-dimethyl-pyridinone (Hdhp) system,however, the results are contradictory and not complete: pH-potentiometry and 51V NMR spectroscopywere used to clarify this complicated system. The eleven peaks in the spectra at different chemical shiftswere assigned to ten stoichiometrically different compounds; four of them are new, never identified orassigned before. Besides the simple mono (in two different protonation states) and bis complexes (inthree different protonation states) a tris complex, three dinuclear and a trinuclear complex were foundbased on the 51V NMR spectra measured at different pH values and various metal ion concentrationsand metal-to-ligand ratios. As a joint evaluation of the two methods, overall stability constants were calculatedfor all species.X-ray structure of the potassium salt of the bis complex, [V(V)O2(dhp)2] was also determined. Thetrans effect of the oxido-oxygens results in maltolato-type coordination of the ligand instead of thecatecholate-like chelation.The redox properties of [V(V)O2(dhp)2] and some other prodrug vanadium(V) bis complexes wereinvestigated by spectrophotometry in aqueous solution via their reduction by glutathione (GSH) andL-ascorbic acid (ASC) under strictly anaerobic conditions and by cyclic voltammetry at physiologicalpH. The reduction was found to be much faster by ASC in all cases as compared with GSH and the reactionrate of the reduction of [V(V)O2(dhp)2] was prominently high most probably due to the formation of thesignificantly higher stability of the corresponding vanadium(IV) complex.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Inorganica Chimica Acta. - 420 (2014), p. 92-102. -
További szerzők:	Enyedy Éva Anna (1975-) (vegyész) Kozma Károly Paár Zsófia Bényei Attila (1962-) (vegyész) Kiss Tamás
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon:

001-es BibID:	BIBFORM008185
Első szerző:	Jakusch Tamás
Cím:	Vanadate complexes in serum: a speciation modeling study / Tamás Jakusch, Annalise Dean, Tamás Oncsik, Attila Csaba Bényei, Valerio Di Marco, Tamas Kiss
Dátum:	2009
Megjegyzések:	The speciations of two drug candidate ligands, 2-hydroxypyridine-N-oxide (Hhpno) and 2-mercaptopyridine-N-oxide (Hmpno), with vanadate (VV) were determined at 25.0 °C and 0.20 mol dm-3 KCl by pH-metric and 51V-NMR methods. At pH 7.4, the two predominant compounds with both ligands are the VO2L2 and VO2L(OH). NH4[VO2(hpno)2]·3H2O was prepared in solid form, and its crystal structure was determined by X-ray diffraction. The stabilities of the complexes VO2L2 of five drug candidate ligands were compared at pH 7.4. In view of the stability sequence hpno > maltol ~ hdp (Hhdp: 3-hydroxy-1,2-dimethyl-4-pyridinone)> mpno > picolinic acid, the first two of these ligands were chosen for equilibrium studies with apotransferrin (apoTf) competition. The VV-apoTf stability constants (log K1 = 6.03 ± 0.10; log K2 = 5.46 ± 0.18) determined by 51V-NMR spectroscopy were confirmed by ultrafiltration. Both methods proved that there seems to be no hydrogencarbonate-vanadate competition for the apoTf anion-binding positions. The other potential high molecular mass VV binder in the serum is human serum albumin (HSA). As no interaction was detected by 51V-NMR spectroscopy or fluorimetry, the binding properties of HSA were quantified on the basis of literature data. As a final conclusion, speciation modeling calculations suggest that, under serum conditions, apoTf is probably the primary metal ion binder, even in the presence of the most stable VV carrier ligands hpno and maltol and HSA plays a negligible role in VV binding.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Dalton Transactions . - 2010 : 39 (2009), p. 212-220. -
További szerzők:	Dean, Annalise Oncsik Tamás Bényei Attila (1962-) (vegyész) Di Marco, Valerio Kiss Tamás
Internet cím:	DOI elektronikus változat
Borító:
Saját polcon:

001-es BibID:	BIBFORM085473
Első szerző:	Kiss Erzsébet
Cím:	VO(IV) complexes of 3-hydroxypicolinic acid : a solution study and the structure of a supramolecular assembly in the solid state / Erzsébet Kiss, Attila Bényei, Tamás Kiss
Dátum:	2003
ISSN:	0277-5387
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk
Megjelenés:	Polyhedron. - 22 : 1 (2003), p. 27-33. -
További szerzők:	Bényei Attila (1962-) (vegyész) Kiss Tamás
Pályázati támogatás:	OTKA 31896/99 OTKA
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon: