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001-es BibID:	BIBFORM099499
035-os BibID:	(WoS)000747265100001 (Scopus)85123424554
Első szerző:	Csupász Tibor (1991-)
Cím:	A New Oxygen Containing Pyclen-Type Ligand as a Manganese(II) Binder for MRI and 52Mn PET Applications: Equilibrium, Kinetic, Relaxometric, Structural and Radiochemical Studies / Tibor Csupász, Dániel Szücs, Ferenc Krisztián Kálmán, Oldamur Hollóczki, Anikó Fekete, Dezső Szikra, Éva Tóth, Imre Tóth, Gyula Tircsó
Dátum:	2022
ISSN:	1420-3049
Megjegyzések:	A new pyclen-3,9-diacetate derivative ligand (H23,9-OPC2A) is synthesized possessing an etheric O-atom opposite to the pyridine ring, to improve the dissociation kinetics of its Mn(II) complex (pyclen = 3,6,9,15-tetraazabicyclo(9.3.1)pentadeca-1(15),11,13-triene). The new ligand is less basic than the N-containing analogue (H23,9-PC2A) due to the non-protonable O-atom. In spite of its lower basicity, the conditional stability of the (Mn(3,9-OPC2A)) (pMn = ?log(Mn(II)), cL = cMn(II) = 0.01 mM. pH = 7.4) remains unaffected (pMn = 8.69), compared to the (Mn(3,9-PC2A)) (pMn = 8.64). The (Mn(3,9-OPC2A)) possesses one water molecule, having a lower exchange rate with bulk solvents (kex298 = 5.3 ??0.4 ? 107 s?1) than (Mn(3,9-PC2A)) (kex298 = 1.26?108 s?1). These mild dif-ferences are rationalized by the density-functional theory (DFT) calculations. The acid assisted dissociation of (Mn(3,9-OPC2A)) is considerably slower (k1 = 2.81 ??0.07 M?1s?1) than that of the complexes of diacetates or bisamides of various 12-membered macrocycles and the parent H23,9-PC2A. The (Mn(3,9-OPC2A)) is inert in rat/human serum as confirmed by 52Mn labeling (nM range), as well as by relaxometry (mM range). However, a 600-fold excess of EDTA (pH = 7.4) or a mixture of essential metal ions, propagated some transchelation/transmetalation in 7 days. The H23,9-OPC2A is labeled efficiently with 52Mn at elevated temperatures, yet at 37 ?C the parent H23,9-PC2A performs slightly better. Ultimately, the H23,9-OPC2A shows advantageous features for further ligand designs for bifunctional chelators. A new pyclen-3,9-diacetate derivative ligand (H23,9-OPC2A) is synthesized possessing an etheric O-atom opposite to the pyridine ring to improve the dissociation kinetics of its Mn(II) complex (pyclen = 3,6,9,15-tetraazabicyclo[9.3.1]pentadeca-1(15),11,13-triene). The new ligand is less basic than the N-containing analogue (H23,9-PC2A) due to the non-protonable O-atom. In spite of its lower basicity, the conditional stability of the [Mn(3,9-OPC2A)] (pMn=-log[Mn(II)], cL=cMn(II)=0.01 mM. pH=7.4) remains unaffected (pMn=8.69) compared to the [Mn(3,9-PC2A)] (pMn=8.64). The [Mn(3,9-OPC2A)] possesses one water molecule, having a lower exchange rate with bulk solvent (kex298=5.3?0.4?107 s-1) than [Mn(3,9-PC2A)] (kex298=1.26?108 s-1). These mild differences are ration-alized by density-functional theory (DFT) calculations. The acid assisted dissociation of [Mn(3,9-OPC2A)] is considerably slower (k1=2.81?0.07 M-1s-1) than that of the complexes of diac-etates or bisamides of various 12-membered macrocycles and the parent H23,9-PC2A. The [Mn(3,9-OPC2A)] is inert in rat/human serum as confirmed by 52Mn labeling (nM range) as well as by relaxometry (mM range). However, 600-fold excess of EDTA (pH=7.4) or a mixture of es-sential metal ions propagated some transchelation/transmetalation in 7 days. The H23,9-OPC2A is labeled efficiently with 52Mn at elevated temperatures, yet at 37 oC the parent H23,9-PC2A per-forms slightly better. Altogether the H23,9-OPC2A shows advantageous features for further lig-and design for bifunctional chelators.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk
Megjelenés:	Molecules. - 27 (2022), p. 1-27. -
További szerzők:	Szücs Dániel (1994-) (gyógyszerész) Kálmán Ferenc K. (1978-) (vegyész) Hollóczki Oldamur (1983-) (okleveles vegyészmérnök) Fekete Anikó (1973-) (vegyész) Szikra Dezső Péter (1983-) (vegyész) Tóth Éva Tóth Imre (1950-) (vegyész) Tircsó Gyula (1977-) (vegyész, kémia tanár)
Pályázati támogatás:	K-120224 OTKA K-128201 OTKA K-134694 OTKA FK-134551 OTKA University of Debrecen Innovation Fund (POC-012) Egyéb the János Bolyai Research Scholarship of the Hungarian Academy of Sciences MTA ÚNKP-21-4 new national excellence program of the Ministry of Human Capacities Egyéb Doctoral School of Chemistry at the University of Debrecen Egyéb
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001-es BibID:	BIBFORM100004
035-os BibID:	(cikkazonosító)58 (WOS)000752865500001 (Scopus)85121683377
Első szerző:	Do, Quyen N. (vegyész)
Cím:	How the Chemical Properties of GBCAs Influence Their Safety Profiles In Vivo / Quyen N. Do, Robert E. Lenkinski, Gyula Tircso, Zoltan Kovacs
Dátum:	2022
ISSN:	1420-3049
Megjegyzések:	The extracellular class of gadolinium-based contrast agents (GBCAs) is an essential tool for clinical diagnosis and disease management. In order to better understand the issues associated with GBCA administration and gadolinium retention and deposition in the human brain, the chemical properties of GBCAs such as relative thermodynamic and kinetic stabilities and their likelihood of forming gadolinium deposits in vivo will be reviewed. The chemical form of gadolinium causing the hyperintensity is an open question. On the basis of estimates of total gadolinium concentration present, it is highly unlikely that the intact chelate is causing the T1 hyperintensities observed in the human brain. Although it is possible that there is a water-soluble form of gadolinium that has high relaxitvity present, our experience indicates that the insoluble gadolinium-based agents/salts could have high relaxivities on the surface of the solid due to higher water access. This review assesses the safety of GBCAs from a chemical point of view based on their thermodynamic and kinetic properties, discusses how these properties influence in vivo behavior, and highlights some clinical implications regarding the development of future imaging agents.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk
Megjelenés:	Molecules. - 27 : 1 (2022), p. 1-19. -
További szerzők:	Lenkinski, Robert E. Tircsó Gyula (1977-) (vegyész, kémia tanár) Kovács Zoltán
Pályázati támogatás:	K-120224 OTKA K-134694 OTKA
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001-es BibID:	BIBFORM106978
035-os BibID:	(Wos)000690091200001 (Scopus)85113323387 (cikkazonosító)4956
Első szerző:	Garda Zoltán (vegyész)
Cím:	Complexes of Bifunctional DO3A-N-(alpha-amino)propinate Ligands with Mg(II), Ca(II), Cu(II), Zn(II), and Lanthanide(III) Ions: Thermodynamic Stability, Formation and Dissociation Kinetics, and Solution Dynamic NMR Studies / Zoltán Garda, Tamara Kócs, István Bányai, José A. Martins, Ferenc Krisztián Kálmán, Imre Tóth, Carlos F. G. C. Geraldes, Gyula Tircsó
Dátum:	2021
ISSN:	1420-3049
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk
Megjelenés:	Molecules. - 26 : 16 (2021), p. 1-26. -
További szerzők:	Kócs Tamara Bányai István (1953-) (vegyész) Martins, José A. Kálmán Ferenc K. (1978-) (vegyész) Tóth Imre (1950-) (vegyész) Geraldes, Carlos Frederico de Gusmão Campos Tircsó Gyula (1977-) (vegyész, kémia tanár)
Pályázati támogatás:	K-128201 OTKA K-134694 OTKA FK-134551 OTKA
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001-es BibID:	BIBFORM106987
035-os BibID:	(Wos)000645403400001 (Scopus)85103919865 (cikkazonosító)1524
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
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