Show simple item record

dc.contributor.authorKálmán, Ferenc
dc.contributor.authorNagy, Viktória
dc.contributor.authorUzal-Varela, Rocío
dc.contributor.authorPérez-Lourido, Paulo
dc.contributor.authorEsteban-Gómez, David
dc.contributor.authorGarda, Zoltán
dc.contributor.authorPota, Kristof
dc.contributor.authorMezei, Roland
dc.contributor.authorPallier, Agnès
dc.contributor.authorTóth, Éva
dc.contributor.authorPlatas-Iglesias, Carlos
dc.contributor.authorTircsó, Gyula
dc.date.accessioned2021-04-06T16:17:45Z
dc.date.available2021-04-06T16:17:45Z
dc.date.issued2021-03-10
dc.identifier.citationKálmán, F.K.; Nagy, V.; Uzal-Varela, R.; Pérez-Lourido, P.; Esteban-Gómez, D.; Garda, Z.; Pota, K.; Mezei, R.; Pallier, A.; Tóth, É.; Platas-Iglesias, C.; Tircsó, G. Expanding the Ligand Classes Used for Mn(II) Complexation: Oxa-aza Macrocycles Make the Difference. Molecules 2021, 26, 1524. https://doi.org/10.3390/molecules26061524es_ES
dc.identifier.issn1420-3049
dc.identifier.urihttp://hdl.handle.net/2183/27664
dc.description.abstract[Abstract] We report two macrocyclic ligands based on a 1,7-diaza-12-crown-4 platform functionalized with acetate (𝑡O2DO2A²⁻) or piperidineacetamide (𝑡O2DO2AMᴾⁱᵖ) pendant arms and a detailed characterization of the correspondingMn(II) complexes. The X-ray structure of [Mn(𝑡O2DO2A)(H₂O)]∙.2H₂O shows that the metal ion is coordinated by six donor atoms of the macrocyclic ligand and one water molecule, to result in seven-coordination. The Cu(II) analogue presents a distorted octahedral coordination environment. The protonation constants of the ligands and the stability constants of the complexes formed with Mn(II) and other biologically relevant metal ions (Mg(II), Ca(II), Cu(II) and Zn(II)) were determined using potentiometric titrations (∕ = 0.15 M NaCl, T = 25 ºC). The conditional stabilities of Mn(II) complexes at pH 7.4 are comparable to those reported for the cyclen-based 𝑡DO2A²⁻ ligand. The dissociation of the Mn(II) chelates were investigated by evaluating the rate constants of metal exchange reactions with Cu(II) under acidic conditions (∕ = 0.15MNaCl, T = 25 ºC). Dissociation of the [Mn(𝑡O2DO2A)(H₂O)] complex occurs through both proton- and metal-assisted pathways, while the [Mn(𝑡O2DO2AMᴾⁱᵖ)(H₂O)] analogue dissociates through spontaneous and proton-assisted mechanisms. The Mn(II) complex of 𝑡O2DO2A²⁻ is remarkably inert with respect to its dissociation, while the amide analogue is significantly more labile. The presence of a water molecule coordinated to Mn(II) imparts relatively high relaxivities to the complexes. The parameters determining this key property were investigated using ¹⁷O NMR (Nuclear Magnetic Resonance) transverse relaxation rates and ¹H nuclear magnetic relaxation dispersion (NMRD) profiles.es_ES
dc.description.sponsorshipThis research was funded by Hungarian National Research, Development and Innovation Office, Projects NKFIH K-120224 and 134694); Ministerio de Economía y Competitividad (CTQ2016-76756-P) and Xunta de Galicia (ED431B 2020/52)es_ES
dc.description.sponsorshipHungarian Scientific Research; NKFIH K-120224
dc.description.sponsorshipHungarian Scientific Research; NKFIH K-134694
dc.description.sponsorshipXunta de Galicia; ED431B 2020/52
dc.language.isoenges_ES
dc.publisherMDPIes_ES
dc.relationinfo:eu-repo/grantAgreement/AEI/Plan Estatal de Investigación Científica y Técnica y de Innovación 2013-2016/CTQ2016-76756-P/ES/NUEVA GENERACION DE AGENTES DE CONTRASTE PARA IMAGEN POR RESONANCIA MAGNETICA (IRM) ALTERNATIVOS A LOS DERIVADOS DE GADOLINIO/
dc.relation.urihttps://doi.org/10.3390/molecules26061524es_ES
dc.rightsAttribution 4.0 Internationales_ES
dc.rights.urihttp://creativecommons.org/licenses/by/4.0/*
dc.subjectManganesees_ES
dc.subjectMagnetic resonance imaginges_ES
dc.subjectStabilityes_ES
dc.subjectDissociation kineticses_ES
dc.subjectWater exchangees_ES
dc.subjectContrast agentses_ES
dc.subjectMacrocycleses_ES
dc.titleExpanding the Ligand Classes Used for Mn(II) Complexation: Oxa-aza Macrocycles Make the Differencees_ES
dc.typeinfo:eu-repo/semantics/articlees_ES
dc.rights.accessinfo:eu-repo/semantics/openAccesses_ES
UDC.journalTitleMoleculeses_ES
UDC.volume26es_ES
UDC.issue6es_ES
UDC.startPage1524es_ES
UDC.endPage1524es_ES


Files in this item

Thumbnail
Thumbnail

This item appears in the following Collection(s)

Show simple item record