Találati lista | Tudóstér

001-es BibID:	BIBFORM106987
035-os BibID:	(Wos)000645403400001 (Scopus)85103919865
Első szerző:	Kálmán Ferenc K. (vegyész)
Cím:	Expanding the Ligand Classes Used for Mn(II) Complexation: Oxa-aza Macrocycles Make the Difference / Ferenc K. Kálmán, Viktória Nagy, Rocío Uzal-Varela, Paulo Pérez-Lourido, David Esteban-Gómez,Zoltán Garda, Kristof Pota, Roland Mezei, Agnès Pallier, Éva Tóth, Carlos Platas-Iglesias, Gyula Tircsó
Dátum:	2021
ISSN:	1420-3049
Megjegyzések:	We report two macrocyclic ligands based on a 1,7-diaza-12-crown-4 platform functionalizedwith acetate (tO2DO2A2?) or piperidineacetamide (tO2DO2AMPip) pendant arms and a detailed char-acterization of the corresponding Mn(II) complexes. The X?ray structure of [Mn(tO2DO2A)(H2O)]·2H2Oshows that the metal ion is coordinated by six donor atoms of the macrocyclic ligand and one watermolecule, to result in seven-coordination. The Cu(II) analogue presents a distorted octahedral coor-dination environment. The protonation constants of the ligands and the stability constants of thecomplexes formed with Mn(II) and other biologically relevant metal ions (Mg(II), Ca(II), Cu(II) andZn(II)) were determined using potentiometric titrations (I= 0.15 M NaCl, T = 25?C). The conditionalstabilities of Mn(II) complexes at pH 7.4 are comparable to those reported for the cyclen-basedtDO2A2?ligand. The dissociation of the Mn(II) chelates were investigated by evaluating the rateconstants of metal exchange reactions with Cu(II) under acidic conditions (I= 0.15 M NaCl, T = 25?C).Dissociation of the [Mn(tO2DO2A)(H2O)] complex occurs through both proton?and metal?assistedpathways, while the [Mn(tO2DO2AMPip)(H2O)] analogue dissociates through spontaneous andproton-assisted mechanisms. The Mn(II) complex oftO2DO2A2 is remarkably inert with respectto its dissociation, while the amide analogue is significantly more labile. The presence of a watermolecule coordinated to Mn(II) imparts relatively high relaxivities to the complexes. The parametersdetermining this key property were investigated using17O NMR (Nuclear Magnetic Resonance)transverse relaxation rates and1H nuclear magnetic relaxation dispersion (NMRD) profiles.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk manganese magnetic resonance imaging stability dissociation kinetics water exchange contrast agents macrocycles
Megjelenés:	Molecules. - 26 : 6 (2021), p. 1-20. -
További szerzők:	Nagy Viktória Uzal-Varela, Rocío Pérez-Lourido, Paulo Esteban-Gómez, David Garda Zoltán (1989-) (vegyész) Póta Kristóf Mezei Roland Pallier, Agnès Tóth Éva Platas-Iglesias, Carlos Tircsó Gyula (1977-) (vegyész, kémia tanár)
Pályázati támogatás:	K-120224 OTKA K-134694 OTKA
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon:

001-es BibID:	BIBFORM129297
Első szerző:	Lucio-Martínez, Fátima
Cím:	[natY/90Y]Yttrium and [natLu/177Lu]Lutetium Complexation by Rigid H4OCTAPA Derivatives. Effect of Ligand Topology / Fátima Lucio-Martínez, Balázs Szilágyi, Rocío Uzal-Varela, Paulo Pérez-Lourido, David Esteban-Gómez, Nicolas Lepareur, Gyula Tircsó, Carlos Platas-Iglesias
Dátum:	2025
ISSN:	0947-6539 1521-3765
Megjegyzések:	We present a detailed investigation on the coordination chemistry of [nat/90Y]Y3+ and [nat/177Lu]Lu3+ with the new acyclic chelator H4CHXOITAPA. This octadentate chelator forms nine-coordinated Y3+ and Lu3+ complexes thanks to the coordination of a water molecule, as demonstrated by the X-ray structure of [Y(HCHXOITAPA)(H2O)] and 1H, 13C and 89Y NMR studies in solution. These complexes display slightly higher thermodynamic stabilities compared with those of the known H4CHXOCTAPA and H4OCTAPA chelators, reaching log KYL and log KLuL values of 21.24(5) and 21.96(1), respectively. Kinetic studies indicate that these complexes dissociate mainly through the spontaneous and proton-assisted pathways at pH 7.4. The chelator can be readily radiolabeled with [90Y]Y3+ and [177Lu]Lu3+ at room temperature in 10 min. The radio-complexes are stable in human serum at 37 ?C, in contrast with the analogues of the known H4CHXOCTAPA and H4OCTAPA chelators, which experience significant dissociation under these conditions. Thus, the H4CHXOITAPA chelator represents the most promising candidate among the H4OCTAPA family for the development of 90Y- and 177Lu based radiopharmaceuticals.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk yttrium lutetium ligands radiopharmaceuticals thermodynamics
Megjelenés:	Chemistry-A European Journal. - 31 : 28 (2025), p. 1-14. -
További szerzők:	Szilágyi Balázs (1998-) (vegyész) Uzal-Varela, Rocío Pérez-Lourido, Paulo Esteban-Gómez, David Lepareur, Nicolas Tircsó Gyula (1977-) (vegyész, kémia tanár) Platas-Iglesias, Carlos
Pályázati támogatás:	K-134694 OTKA University of Debrecen's Publication Support Programme Egyéb Labex IRON (grant no. ANR-11-LABX-0018) Egyéb Coordinated Research Project F22078 organized by the International Atomic Energy Agency (IAEA) Egyéb Ministerio de Ciencia e Innovación (Grant PID2022-138335NB-I00) and Xunta de Galicia (ED431C 2023/33) Egyéb Centro de Supercomputación de Galicia (CESGA) Egyéb CACTI(Universidade de Vigo) Egyéb
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon:

001-es BibID:	BIBFORM100007
035-os BibID:	(WoS)000739628200001 (Scopus)85123758171
Első szerző:	Pérez-Lourido, Paulo
Cím:	Stable and inert macrocyclic cobalt(II) and nickel(II) complexes with paraCEST response / Paulo Pérez-Lourido, Enikő Madarasi, Fanni Antal, David Esteban-Gómez, Gaoji Wang, Goran Angelovski, Carlos Platas-Iglesias, Gyula Tircsó, Laura Valencia
Dátum:	2022
ISSN:	1477-9226
Megjegyzések:	We report the synthesis of the macrocyclic ligands 3,9 PC2AMH (2,2'-(3,6,9-triaza-1(2,6)-pyridinacyclodecaphane-3,9-diyl)diacetamide) and 3,9-PC2AMtBu (2,2'-(3,6,9-triaza-1(2,6)-pyridinacyclodecaphane-3,9-diyl)bis(N-tert-butyl)acetamide) which contain a pyclen platform functionalized with acetamide or tert-butylacetamide pendant arms at positions 3 and 9 of the macrocyclic unit. The corresponding Co(II) and Ni(II) complexes were prepared, isolated and characterised as potential paramagnetic chemical exchange saturation transfer (paraCEST) agents. The X-ray structures of the Ni(II) complexes reveal six-coordination of the ligands to the metal ion. The Co(II) complex with 3,9-PC2AMtBu shows a similar six-coordinate structure in the solid state, while the Co(II) complex with 3,9 PC2AMH contains a seven-coordinate metal ion, seventh coordination being completed by the presence of an inner-sphere water molecule. The structure of the Co(II) complexes was investigated using 1H NMR spectroscopy and computational methods. The complexes present a seven-coordinate structure in solution, as demonstrated by the analysis of the paramagnetic shifts using density functional theory. Ligand protonation constants and stability constants of the complexes with 3,9 PC2AMH were determined using potentiometric titrations (I=0,15 M NaCl). The Co(II) complex was found to be more stable than the Ni(II) analogue (log KCoL = 14.46(5) and log KNiL = 13.15(3)). However, the Ni(II) and Co(II) complexes display similar rate constants characterizing the proton-assisted dissociation mechanism. The presence of highly shifted 1H NMR signals due to the amide protons in slow exchange with bulk water results in sizeable CEST signals, which are observed at +67 and +15 ppm for the Co(II) complex with 3,9 PC2AMH and +42 and +7 ppm for the Ni(II) analogue at 25 oC .
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk paraCEST PC2A-bis(amides) stability inertnes, structure
Megjelenés:	Dalton Transactions. - 51 : 4 (2022), p. 1580-1593. -
További szerzők:	Madarasi Enikő (1995-) kémia tanár Antal Fanni Esteban-Gómez, David Wang, Gaoji Angelovski, Goran Platas-Iglesias, Carlos Tircsó Gyula (1977-) (vegyész, kémia tanár) Valencia, Laura
Pályázati támogatás:	K-120224 OTKA K-134694 OTKA Doctoral School of Chemistry at the University of Debrecen, Debrecen, Hungary Egyéb COST Action CA15209 "European Network on NMR Relaxometry Egyéb Bilateral Hungarian-Spanish Science and Technology Cooperation Program (2019-2.1.11- TET-2019-00084 supported by NKFIH). Egyéb
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon: