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dc.contributor.advisor[Abstract] 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 (Mn 2+ , Cu 2+ and Gd 3+ ) formed with octadentate ligands based on a cyclen platform incorporating two picolinate pendant arms (dodpa 2− and Medodpa 2− ). The stability constants of the complexes were accessed by m ultiple methods (pH - potentiometry, direct and competition UV - vis spectrophotometry and 1 H - relaxometry). The stability constants of the complexes formed with dodpa 2− and Medodpa 2− do not differ significantly ( e.g. log K [Mn(dodpa)] = 17.40 vs. log K [Mn(Medodp a)] = 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 brou ght by the methyl groups has no significant effect on the stability of the complexes. The stability constants of the Mn 2+ complexes formed with the cyclen dipicolinates were found to be ca. 3 log K units higher than t hose determined for the complex of the cyclen monopicolinate (dompa − ), which indicates that the se cond picolin ate moiety attached to the backbone of the macrocycle is very likely coordinated to the Mn 2+ 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 ( k 1 = 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)] ( k 1 = 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.ES_es
dc.contributor.authorRodríguez-Rodríguez, Aurora
dc.contributor.authorGarda, Zoltán
dc.contributor.authorRuscsák, Erika
dc.contributor.authorEsteban-Gómez, David
dc.contributor.authorBlas, Andrés de
dc.contributor.authorRodríguez-Blas, Teresa
dc.contributor.authorLima, Luís M. P.
dc.contributor.authorBeyler, Maryline
dc.contributor.authorTripier, Raphaël
dc.contributor.authorTircsó, Gyula
dc.contributor.authorPlatas-Iglesias, Carlos
dc.date.accessioned2017-10-30T12:17:39Z
dc.date.available2017-10-30T12:17:39Z
dc.date.issued2015-01-20
dc.identifier.citationStable Mn2+, Cu2+ and Ln3+ complexes with cyclen-based ligands functionalized with picolinate pendant arms. A. Rodríguez-Rodríguez, Z. Garda, E. Ruscsák, D. Esteban-Gómez, A. de Blas, T. Rodríguez-Blas, L. M. P. Lima, M. Beyler, R. Tripier, G. Tircsó and C. Platas-Iglesias, Dalt. Trans., 2015, 44, 5017–5031.es_ES
dc.identifier.issn1477-9226
dc.identifier.issn1477-9234
dc.identifier.urihttp://hdl.handle.net/2183/19664
dc.description.abstract[Abstract] 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 (Mn 2+ , Cu 2+ and Gd 3+ ) formed with octadentate ligands based on a cyclen platform incorporating two picolinate pendant arms (dodpa 2− and Medodpa 2− ). The stability constants of the complexes were accessed by m ultiple methods (pH - potentiometry, direct and competition UV - vis spectrophotometry and 1 H - relaxometry). The stability constants of the complexes formed with dodpa 2− and Medodpa 2− do not differ significantly ( e.g. log K [Mn(dodpa)] = 17.40 vs. log K[Mn(Medodp a)] = 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 brou ght by the methyl groups has no significant effect on the stability of the complexes. The stability constants of the Mn 2+ complexes formed with the cyclen dipicolinates were found to be ca. 3 log K units higher than t hose determined for the complex of the cyclen monopicolinate (dompa − ), which indicates that the se cond picolin ate moiety attached to the backbone of the macrocycle is very likely coordinated to the Mn 2+ 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 ( k 1 = 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)] ( k 1 = 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.
dc.description.sponsorshipHungarian Scientific Research Fund. OTKA; K-84291es_ES
dc.description.sponsorshipHungarian Scientific Research Fund. OTKA; K-109029es_ES
dc.description.sponsorshipEuropean Commission; TÁMOP-4.2.2.A-11/1/KONV-2012-0043es_ES
dc.language.isoenges_ES
dc.publisherRoyal Society of Chemistryes_ES
dc.relation.urihttps://doi.org/10.1039/C4DT02985Bes_ES
dc.subjectCyclen-based ligandses_ES
dc.subjectLanthanide complexeses_ES
dc.subjectCrystal structureses_ES
dc.subjectTransition-metal complexeses_ES
dc.subjectPicolinate pendantses_ES
dc.titleStable Mn2+, Cu2+ and Ln3+ complexes with cyclen-based ligands functionalized with picolinate pendant armses_ES
dc.typeinfo:eu-repo/semantics/articlees_ES
dc.rights.accessinfo:eu-repo/semantics/openAccesses_ES
UDC.journalTitleDalton Transactionses_ES
UDC.volume44es_ES
UDC.issue11es_ES
UDC.startPage5017es_ES
UDC.endPage5031es_ES


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