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001-es BibID:BIBFORM103530
035-os BibID:(WOS)000541873600033 (Scopus)85084399701
Első szerző:Garda Zoltán (vegyész)
Cím:Unexpected Trends in the Stability and Dissociation Kinetics of Lanthanide(III) Complexes with Cyclen-Based Ligands across the Lanthanide Series / Zoltán Garda, Viktoria Nagy, Aurora Rodríguez-Rodríguez, Rosa Pujales-Paradela, Véronique Patinec, Goran Angelovski, Éva Tóth, Ferenc K. Kálmán, David Esteban-Gómez, Raphaël Tripier, Carlos Platas-Iglesias, Gyula Tircsó
Dátum:2020
ISSN:0020-1669 1520-510X
Megjegyzések:We report a detailed study of the thermodynamic stability and dissociation kinetics of lanthanide complexes with two ligands containing a cyclen unit, a methyl group, a picolinate arm, and two acetate pendant arms linked to two nitrogen atoms of the macrocycle in either cis (1,4-H(3)DO2APA) or trans (1,7-H(3)DO2APA) positions. The stability constants of the Gd3+ complexes with these two ligands are very similar, with log K-GdL values of 16.98 and 16.33 for the complexes of 1,4-H(3)DO2APA and 1,7-H(3)DO2APA, respectively. The stability constants of complexes with 1,4-H(3)DO2APA follow the usual trend, increasing from log K-LaL = 15.96 to log K-LuL = 19.21. However, the stability of [Ln(1,7-DO2APA)] complexes decreases from log K = 16.33 for Gd3+ to 14.24 for Lu3+. The acid-catalyzed dissociation rates of the Gd3+ complexes differ by a factor of similar to 15, with rate constants (k(1)) of 1.42 and 23.5 M(-1)s(-1) for [Gd(1,4-DO2APA)] and [Gd(1,7DO2APA)], respectively. This difference is magnified across the lanthanide series to reach a 5 orders of magnitude higher k(1) for [Yb(1,7-DO2APA)] (1475 M(-1)s(-1)) than for [Yb(1,4-DO2APA)] (5.79 x 10(-3)M(-1)s(-1)).The acid catalyzed mechanism involves the protonation of a carboxylate group, followed by a cascade of proton-transfer events that result in the protonation of a nitrogen atom of the cyclen unit. Density functional theory calculations suggest a correlation between the strength of the Ln-O-carboxylate bonds and the kinetic inertness of the complex, with stronger bonds providing more inert complexes. The H-1 NMR resonance of the coordinated water molecule in the [Yb(1,7-DO2APA)] complex at 176 ppm provides a sizable chemical exchange saturation transfer effect thanks to a slow water exchange rate of (15.9 +/- 1.6) x 10(3) s(-1).
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Inorganic Chemistry. - 59 : 12 (2020), p. 8184-8195. -
További szerzők:Nagy Viktória Rodríguez-Rodríguez, Aurora Pujales-Paradela, Rosa Patinec, Véronique Angelovski, Goran Tóth Éva Kálmán Ferenc K. (1978-) (vegyész) Esteban-Gómez, David Tripier, Raphaël Platas-Iglesias, Carlos Tircsó Gyula (1977-) (vegyész, kémia tanár)
Pályázati támogatás:GINOP-2.3.2-15-2016-00008
GINOP
NKFIH-K-120224
Egyéb
NKFIH-K-128201
Egyéb
2019-2.1.11-TÉT-2019-00084
Egyéb
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2.

001-es BibID:BIBFORM067433
Első szerző:Rodríguez-Rodríguez, Aurora
Cím:Stable Mn2+, Cu2+ and Ln3+ complexes with cyclen-based ligands functionalized with picolinate pendant arms / Aurora Rodríguez-Rodríguez, Zoltán Garda, Erika Ruscsák, David Esteban-Gómez, Andrés de Blas, Teresa Rodríguez-Blas, Luís M. P. Lima, Maryline Beyler, Raphaël Tripier, Gyula Tircsó, Carlos Platas-Iglesias
Dátum:2015
ISSN:1477-9226
Megjegyzések:In this study we present the results of the equilibrium, dissociation kinetics, DFT and X-ray crystallographic studies performed on the complexes of metal ions of biomedical importance (Mn2+, Cu2+ and Gd3+) formed with octadentate ligands based on a cyclen platform incorporating two picolinate pendant arms (dodpa2? and Medodpa2?). The stability constants of the complexes were accessed by multiple methods (pH-potentiometry, direct and competition UV-vis spectrophotometry and 1H-relaxometry). The stability constants of the complexes formed with dodpa2? and Medodpa2? do not differ significantly (e.g. log K[Mn(dodpa)] = 17.40 vs. log K[Mn(Medodpa)] = 17.46, log K[Cu(dodpa)] = 24.34?25.17 vs. log K[Cu(Medodpa)] = 24.74 and log K[Gd(dodpa)]+ = 17.27 vs. log K[Gd(Medodpa)]+ = 17.59), which indicates that the steric hindrance brought by the methyl groups has no significant effect on the stability of the complexes. The stability constants of the Mn2+ complexes formed with the cyclen dipicolinates were found to be ca. 3 log K units higher than those determined for the complex of the cyclen monopicolinate (dompa?), which indicates that the second picolinate moiety attached to the backbone of the macrocycle is very likely coordinated to the Mn2+ ion. However, the stability of the [Cu(dodpa)] and [Cu(Medodpa)] complexes agrees well with the stability constant of [Cu(dompa)]+, in line with the hexadentate coordination around the metal ion observed in the X-ray structure of [Cu(Medodpa)]. The [Gd(dodpa)]+ and [Gd(Medodpa)]+ complexes display a fairly high kinetic inertness, as the rate constants of acid catalysed dissociation (k1 = 2.5(4) ? 10?3 and 8.3(4) ? 10?4 M?1 s?1 for [Gd(dodpa)]+ and [Gd(Medodpa)]+, respectively) are smaller than the value reported for [Gd(do3a)] (k1 = 2.5 ? 10?2 M?1 s?1). The [Mn(dodpa)] complex was found to be more inert than [Mn(Medodpa)]. The results of the diffusion-ordered NMR spectroscopy (DOSY) and DFT calculations of diamagnetic [La(dodpa)]+ and [Lu(dodpa)]+ complexes indicate the formation of a trinuclear entity of the La complex in aqueous solution.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
cyclen-based ligand
transition metal
lanthanide
picolinate pendant
thermodynamic stability
kinetic inertness
Megjelenés:Dalton Transactions 44 (2015), p. 5017-5031. -
További szerzők:Garda Zoltán (1989-) (vegyész) Ruscsák Erika (1989-) (vegyész) Esteban-Gómez, David Blas, Andrès de Rodríguez-Blas, Teresa Lima, Luís M. P. Beyler, Maryline Tripier, Raphaël Tircsó Gyula (1977-) (vegyész, kémia tanár) Platas-Iglesias, Carlos
Pályázati támogatás:OTKA-84291
OTKA
OTKA-109029
OTKA
TÁMOP 4.2.2.A-11/1/KONV-2012-0043
TÁMOP
János Bolyai Research Scholarship
MTA
COST TD1004 " Theragnostics Imaging and Therapy: An Action to Develop Novel Nano-sized Systems for Imaging-Guided Drug Delivery "
Egyéb
CM1006 European F-Element Network (EUFEN) Actions
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Intézményi repozitóriumban (DEA) tárolt változat
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3.

001-es BibID:BIBFORM067424
035-os BibID:(WoS)000395753000022 (Scopus)85006969224
Első szerző:Rodríguez-Rodríguez, Aurora
Cím:Definition of the labile capping bond effect in lanthanide complexes / Aurora Rodríguez-Rodríguez, Martín Regueiro-Figueroa, David Esteban-Gómez, Teresa Rodríguez-Blas, Véronique Patinec, Raphaël Tripier, Gyula Tircsó, Fabio Carniato, Mauro Botta and Carlos Platas-Iglesias
Dátum:2017
ISSN:0947-6539
Megjegyzések:Two macrocyclic ligands containing a cyclen unit, a methyl group, a picolinate arm, and two acetate pendant arms attached to two nitrogen atoms of the macrocycle either in trans (1,7-H3Medo2?ampa = 2,2·-(7-((6-carboxypyridin-2-yl)methyl)-10-methyl-1,4,7,10-tetraazacyclododecane-1,4-diyl)diacetic acid) or in cis (1,4-H3Medo2?ampa) positions are reported. These ligands provide eight-coordination to the Ln3+ ions, leaving a coordination position available for a water molecule that occupies a capping position in the twisted square antiprismatic polyhedron (1,4-H3Medo2?ampa) or one of the positions of the square antiprism (1,7-H3Medo2?ampa). The charge neutral [Gd(1,7-Medo2?ampa)] complex presents an unprecedentedly low water-exchange rate (kex298=8.8?103?s?1), whereas water exchange in [Gd(1,4-Medo2?ampa)] is three orders of magnitude faster (kex298=6.6?106?s?1). These results showcase the labile capping bond phenomenon: A ligand occupying a capping position is hindered by the environment and thus is intrinsically labile.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
density functional calculations
gadolinium
magnetic resonance imaging
NMR spectroscopy
water exchange
Megjelenés:Chemistry - a European Journal. - 23 : 5 (2017), p. 1110-1117. -
További szerzők:Regueiro-Figueroa, Martín Esteban-Gómez, David Rodríguez-Blas, Teresa Patinec, Véronique Tripier, Raphaël Tircsó Gyula (1977-) (vegyész, kémia tanár) Carniato, Fabio Botta, Mauro Platas-Iglesias, Carlos
Pályázati támogatás:GINOP-2.3.2-15-2016-00008
GINOP
OTKA-109029
OTKA
OTKA-120224
OTKA
János Bolyai Research Scholarship
MTA
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
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4.

001-es BibID:BIBFORM067299
035-os BibID:(WoS)000371753500032 (Scopus)84960430930
Első szerző:Rodríguez-Rodríguez, Aurora
Cím:Complexation of Ln3+ Ions with Cyclam Dipicolinates: A Small Bridge that Makes Huge Differences in Structure, Equilibrium, and Kinetic Properties / Aurora Rodríguez-Rodríguez, Martín Regueiro-Figueroa, David Esteban-Gómez, Raphaël Tripier, Gyula Tircsó, Ferenc Krisztián Kálmán, Attila Csaba Bényei, Imre Tóth, Andrés de Blas, Teresa Rodríguez-Blas, Carlos Platas-Iglesias
Dátum:2016
ISSN:0020-1669
Megjegyzések:The coordination properties toward the lanthanide ions of two macrocyclic ligands based on a cyclam platform containing picolinate pendant arms have been investigated. The synthesis of the ligands was achieved by using the well-known bis-aminal chemistry. One of the cyclam derivatives (cb-tedpa2?) is reinforced with a cross-bridge unit, which results in exceptionally inert [Ln(cb-tedpa)]+ complexes. The X-ray structures of the [La(cb-tedpa)Cl], [Gd(cb-tedpa)]+, and [Lu(Me2tedpa)]+ complexes indicate octadentate binding of the ligands to the metal ions. The analysis of the Yb3+-induced shifts in [Yb(Me2tedpa)]+ indicates that this complex presents a solution structure very similar to that observed in the solid state for the Lu3+ analogue. The X-ray structures of [La(H2Me2tedpa)2]3+ and [Yb(H2Me2tedpa)2]3+ complexes confirm the exocyclic coordination of the metal ions, which gives rise to coordination polymers with the metal coordination environment being fulfilled by oxygen atoms of the picolinate groups and water molecules. The X-ray structure of [Gd(Hcb-tedpa)2]+ also indicates exocyclic coordination that in this case results in a discrete structure with an eight-coordinated metal ion. The nonreinforced complexes [Ln(Me2tedpa)]+ were prepared and isolated as chloride salts in nonaqueous media. However, these complexes were found to undergo dissociation in aqueous solution, except in the case of the complexes with the smallest Ln3+ ions (Ln3+ = Yb3+ and Lu3+). A DFT investigation shows that the increased stability of the [Ln(Me2tedpa)]+ complexes in solution across the lanthanide series is the result of an increased binding energy of the ligand due to the increased charge density of the Ln3+ ion.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
lanthanide
complex
cross-bridged
equilibrium
kinetic
cyclam
Megjelenés:Inorganic Chemistry. - 55 : 5 (2016), p. 2227-2239. -
További szerzők:Regueiro-Figueroa, Martín Esteban-Gómez, David Tripier, Raphaël Tircsó Gyula (1977-) (vegyész, kémia tanár) Kálmán Ferenc K. (1978-) (vegyész) Bényei Attila (1962-) (vegyész) Tóth Imre (1950-) (vegyész) Blas, Andrès de Rodríguez-Blas, Teresa Platas-Iglesias, Carlos
Pályázati támogatás:OTKA-84291
OTKA
OTKA-109029
OTKA
COST CM1006 "European F-Element Network (EuFen)"
Egyéb
COST TD1004 "Theragnostics Imaging and Therapy: An Action to Develop Novel Nanosized Systems for Imaging- Guided Drug Delivery"
Egyéb
Bolyai János Kutatási Ösztöndíj
MTA
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5.

001-es BibID:BIBFORM057620
Első szerző:Rodríguez-Rodríguez, Aurora
Cím:Lanthanide(III) Complexes with a Reinforced Cyclam Ligand Show Unprecedented Kinetic Inertness / Aurora Rodríguez-Rodríguez, David Esteban-Gómez, Raphaël Tripier, Gyula Tircsó, Zoltán Garda, Imre Tóth, Andrés de Blas, Teresa Rodríguez-Blas, Carlos Platas-Iglesias
Dátum:2014
ISSN:0002-7863
Megjegyzések:Lanthanide(III) complexes of a cross-bridged cyclam derivative containing two picolinate pendant arms are kinetically inert in very harsh conditions such as 2 M HCl, with no dissociation being observed for at least 5 months. Importantly, the [Ln(dota)] complexes, which are recognized to be extremely inert, dissociate under these conditions with lifetimes in the range ca. 1 minute to 12 hours depending upon the Ln3+ ion. X-ray diffraction studies reveal octadentate binding of the ligand to the metal ion in the [Eu(cb-tedpa)]+ complex, while 1H and 13C NMR experiments in D2O point to the presence of a single diastereoisomer in solution with a very rigid structure. The structure of the complexes in the solid state is retained in solution, as demonstrated by the analysis of the Yb3+-induced paramagnetic shifts.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Lanthanide(III) Complexes
Reinforced Cyclam Ligand
kinetics inertness
picolinates
Megjelenés:Journal Of The American Chemical Society. - 136 : 52 (2014), p. 17954-17957. -
További szerzők:Esteban-Gómez, David Tripier, Raphaël Tircsó Gyula (1977-) (vegyész, kémia tanár) Garda Zoltán (1989-) (vegyész) Tóth Imre (1950-) (vegyész) de Blas, Andrés Rodríguez-Blas, Teresa Platas-Iglesias, Carlos
Pályázati támogatás:Ministerio de Educación y Ciencia (MEC, CTQ2009-10721), Fondo Europeo de Desarrollo Regional (FEDER, CTQ2009-10721) and Xunta de Galicia (CN 2012/011) for generous financial support and Centro de Supercomputación de Galicia (CESGA)
Egyéb
COST CM1006 "European F-Element Network (EuFen)
Egyéb
COST TD1004 "Theragnostics Imaging and Therapy: An Action to Develop Novel Nanosized Systems for Imaging-Guided Drug Delivery"
Egyéb
János Bólyai Research Scholarship of the Hungarian Academy of Sciences
MTA
K-84291
OTKA
K-109029
OTKA
TÁMOP-4.2.2.A-11/1/KONV-2012-0043
TÁMOP
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
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