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001-es BibID:BIBFORM116497
035-os BibID:(WoS)001101303500001 (Scopus)85176281648
Első szerző:Bunda Szilvia (vegyész)
Cím:Bipyridil-based chelators for Gd(III) complexation: kinetic, structural and relaxation properties / Szilvia Bunda, Norbert Lihi, Zsófia Szaniszló, David Esteban-Gómez, Carlos Platas-Iglesias, Mónika Kéri, Gábor Papp, Ferenc Krisztián Kálmán
Dátum:2023
ISSN:1477-9226
Megjegyzések:In the last 20 years, research in the field of MRI (magnetic resonance imaging) contrast agents (CAs) has been intensified due to the emergence of a disease called nephrogenic systemic fibrosis (NSF). NSF has been linked to the in vivo dissociation of certain Gd(III)-based compounds applied in MRI as CAs. To prevent the dechelation of the probes after intravenous injection, the improvement of their in vivo stability is highly desired. The inertness of the Gd(III) chelates can be increased through the rigidification of the ligand structure. One of the potential ligands is (2,2 ',2 '',2 '''-(([2,2 '-bipyridine]-6,6 '-diylbis(methylene))bis(azanetriyl))tetraacetic acid) (H(4)DIPTA), which has been successfully used as a fluorescent probe for lanthanides; however, it has never been considered as a potential chelator for Gd(III) ions. In this paper, we report the thermodynamic, kinetic and structural features of the complex formed between Gd(III) and DIPTA. Since the solubility of the [Gd(DIPTA)](-) chelate is very low under acidic conditions, hampering its thermodynamic characterization, we can only assume that its stability is close to that determined for the structural analogue [Gd(FENTA)](-) (H(4)FENTA: (1,10-phenanthroline-2,9-diyl)bis(methyliminodiacetic acid)), which is similar to that determined for the agent [Gd(DTPA)](2-) routinely used in clinical practice. Unfortunately, the inertness of [Gd(DIPTA)](-) is significantly lower (t(1/2) = 1.34 h) than that observed for [Gd(EGTA)](-) and [Gd(DTPA)](2-) as a result of its spontaneous dissociation pathway during dechelation. The relaxivity values of [Gd(DIPTA)](-) are comparable with those of [Gd(FENTA)](-) and somewhat higher than the values characterizing [Gd(DTPA)](2-). Luminescence lifetime measurements indicate the presence of one water molecule (q = 1) in the inner sphere of the complex with a relatively high water exchange rate (k(ex)(298) = 43(5) x 10(6) s(-1)). DFT calculations suggest a rigid distorted tricapped trigonal prismatic polyhedron for the Gd(III) complex. On the basis of these results, we can conclude that the bipyridine backbone is not favourable with respect to the inertness of the chelate.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
koordinációs kémia
Gd(III)-komplex
kinetika
relaxivitás
Megjelenés:Dalton Transactions. - 52 : 45 (2023), p. 17030-17040. -
További szerzők:Lihi Norbert (1990-) (vegyész) Szaniszló Zsófia (1998-) (vegyészmérnök) Esteban-Gómez, David Platas-Iglesias, Carlos Kéri Mónika (1984-) (környezetkutató vegyész) Papp Gábor (1976-) (vegyész, kémikus) Kálmán Ferenc K. (1978-) (vegyész)
Pályázati támogatás:FK-134551
OTKA
2019-2.1.11-TET-2019-00084
Egyéb
ÚNKP-22-5
Egyéb
ÚNKP-23-5
Egyéb
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DOI
Intézményi repozitóriumban (DEA) tárolt változat
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2.

001-es BibID:BIBFORM084628
Első szerző:Papp Gábor (vegyész, kémikus)
Cím:Classical and non-classical phosphine-Ru(II)-hyidrides in aqueous solution: Many, various, and useful. / Papp Gábor Csaba, Győrváriné Horváth Henrietta, Gabor Laurenczy, Szatmári Imre, Kathó Ágnes, Joó Ferenc
Dátum:2013
ISSN:1477-9226 1477-9234
Megjegyzések:Hydrogenation of the water-soluble [{RuCl2(mtppms)2}2] (mtppms = monosulfonated triphenylphosphine) was studied in aqueous solutions in the presence of excess mtppms both with H2 and with aqueous HCOONa. Depending on the reductant, the pH and H2 pressure altogether nine hydride species were identified. In acidic solutions at 1 bar H2 pressure the known [RuHCl(mtppms)3] (1) and [{RuHCl(mtppms)2}2] (3) were formed, however, elevated pressure led to the formation of trans-[RuH2(mtppms)4] (11). In basic solutions at atmospheric pressure cis-fac-[RuH2(H2O)(mtppms)3] (12) was observed which was readily replaced by [RuH2(?2-H2)(mtppms)3] (13) at higher H2 pressures. 13 is the first water-soluble and stable ?2-H2 Ru(II)-complex stabilized only by monodentate phosphine ligands. [RuHBr(mtppms)3] (9) and [RuHI(mtppms)3] (10) were obtained analogously to 1. In concentrated aqueous HCOONa solutions (often used in H-transfer hydrogenations) the major species was trans-[RuH2(HCOO)(mtppms)]? (14) while in dilute solutions trans-[RuH2(H2O)(mtppms)3] (15) could be observed. Formation of these various hydride species offers an explanation for the earlier observed pH and pressure dependence of the rates and selectivities in hydrogenation of unsaturated aldehydes catalyzed by [{RuCl2(mtppms)2}2] + mtppms.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Dalton Transactions. - 42 : 2 (2013), p. 521-529. -
További szerzők:Horváth H. Henrietta (1979-) (vegyész) Laurenczy Gábor Szatmári Imre (1985-) (vegyész) Kathó Ágnes (1954-) (vegyész, kémikus) Joó Ferenc (1949-) (vegyész)
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Intézményi repozitóriumban (DEA) tárolt változat
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3.

001-es BibID:BIBFORM074562
Első szerző:Papp Gábor (vegyész, kémikus)
Cím:Classical and non-classical phosphine-Ru(II)-hydrides in aqueous solutions: many, various, and useful / Gábor Papp, Henrietta Horváth, Gábor Laurenczy, Imre Szatmári, Ágnes Kathó, Ferenc Joó
Dátum:2013
ISSN:1477-9226
Megjegyzések:Hydrogenation of the water-soluble [{RuCl2(mtppms)2}2] (mtppms = monosulfonated triphenylphosphine) was studied in aqueous solutions in the presence of excess mtppms both with H2 and with aqueous HCOONa. Depending on the reductant, the pH and H2 pressure altogether nine hydride species were identified. In acidic solutions at 1 bar H2 pressure the known [RuHCl(mtppms)3] (1) and [{RuHCl(mtppms)2}2] (3) were formed, however, elevated pressure led to the formation of trans-[RuH2(mtppms)4] (11). In basic solutions at atmospheric pressure cis-fac-[RuH2(H2O)(mtppms)3] (12) was observed which was readily replaced by [RuH2(?2-H2)(mtppms)3] (13) at higher H2 pressures. 13 is the first water-soluble and stable ?2-H2 Ru(II)-complex stabilized only by monodentate phosphine ligands. [RuHBr(mtppms)3] (9) and [RuHI(mtppms)3] (10) were obtained analogously to 1. In concentrated aqueous HCOONa solutions (often used in H-transfer hydrogenations) the major species was trans-[RuH2(HCOO)(mtppms)]? (14) while in dilute solutions trans-[RuH2(H2O)(mtppms)3] (15) could be observed. Formation of these various hydride species offers an explanation for the earlier observed pH and pressure dependence of the rates and selectivities in hydrogenation of unsaturated aldehydes catalyzed by [{RuCl2(mtppms)2}2] + mtppms.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Dalton Transactions. - 42 : 2 (2013), p. 521-529. -
További szerzők:Horváth Henrietta (1975-) (vegyész) Laurenczy Gábor Szatmári Imre (1985-) (vegyész) Kathó Ágnes (1954-) (vegyész, kémikus) Joó Ferenc (1949-) (vegyész)
Pályázati támogatás:OTKA-101372
OTKA
TÁMOP-4.2.1/B-09/1/KONV-2010-0007
TÁMOP
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Intézményi repozitóriumban (DEA) tárolt változat
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