Listar GI-REACT! - Artigos por data de publicación
Mostrando ítems 21-40 de 103
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High relaxivity Mn2+-based MRI contrast agents
(Wiley, 2014-12-16)[Abstract] Stable Mn2+ mono- and binuclear complexes containing pentadentate 6,6′-((methylazanediyl)bis(methylene)) dipicolinic acid coordinating units give remarkably high relaxivities due to the presence of two inner-sphere ... -
Stable Mn2+, Cu2+ and Ln3+ complexes with cyclen-based ligands functionalized with picolinate pendant arms
(Royal Society of Chemistry, 2015-01-20)[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 ... -
Importance of outer-sphere and aggregation phenomena in the relaxation properties of phosphonated gadolinium complexes with potential applications as MRI contrast agents
(Wiley, 2015-04-10)[Abstract] A series composed of a tetra-, a tris- and a bisphosphonated ligand based on a pyridine scaffold (L4, L3 and L2, respectively) was studied within the frame of lanthanide (Ln) coordination. The stability constants ... -
Gd3+-based magnetic resonance imaging contrast agent responsive to Zn2+
(American Chemical Society, 2015-10-15)[Abstract] We report the heteroditopic ligand H5L, which contains a DO3A unit for Gd3+ complexation connected to an NO2A moiety through a N-propylacetamide linker. The synthesis of the ligand followed a convergent route ... -
Exceptionally inert lanthanide(III) PARACEST MRI contrast agents based on an 18-membered macrocyclic platform
(Wiley, 2015-12-14)[Abstract] We report a macrocyclic ligand based on a 3,6,10,13-tetraaza-1,8(2,6)-dipyridinacyclotetradecaphane platform containing four hydroxyethyl pendant arms (L1) that forms extraordinary inert complexes with Ln3+ ions. ... -
Approaching the kinetic inertness of macrocyclic gadolinium(III)-based MRI contrast agents with highly rigid open-chain derivatives
(Wiley, 2016-01-08)[Abstract] A highly rigid open-chain octadentate ligand (H4cddadpa) containing a diaminocylohexane unit to replace the ethylenediamine bridge of 6,6′-[(ethane-1,2 diylbis{(carboxymethyl)azanediyl})bis(methylene)] dipicolinic ... -
[C–H⋯anion] interactions mediate the templation and anion binding properties of topologically non-trivial metal–organic structures in aqueous solutions
(Royal Society of Chemistry, 2016-02-12)[Abstract] Two synthetic approaches—temperature variation and anion templation—allowed for the selective formation of a [2]catenane ([2]C4+) or a trefoil knot (TK6+), or for the enhanced formation of a Solomon link (SL8+), ... -
Synthesis and characterisation of bismacrocyclic DO3A-amide derivatives – an approach towards metal-responsive PARACEST agents
(Royal Society of Chemistry, 2016-02-26)[Abstract] Three new bismacrocyclic Ln3+ chelates consisting of triamide derivatives of cyclen with glycine, methyl and tert-butyl substituents (L1–3, respectively) linked to an acyclic EGTA-derived calcium chelator were ... -
Magnetic anisotropies in rhombic lanthanide(III) complexes do not conform to Bleaney’s theory
(American Chemical Society, 2016-04-04)[Abstract] We report a complete set of magnetic susceptibilities of lanthanide complexes with a macrocyclic ligand based on a 3,6,10,13-tetraaza-1,8(2,6)-dipyridinacyclotetradecaphane platform containing four hydroxyethyl ... -
Paramagnetic lanthanide chelates for multicontrast MRI
(Royal Society of Chemistry, 2016-06-02)[Abstract] The preparation of a paramagnetic chelator that serves as a platform for multicontrast MRI, and can be utilized either as a T1-weighted, paraCEST or 19F MRI contrast agent is reported. Its europium(III) complex ... -
Stimuli-responsive metal-directed self-assembly of a ring-in-ring complex
(Royal Society of Chemistry, 2016-06-06)[Abstract] Concentration, temperature and/or solvent polarity control the speciation on the metal-directed self-assembly of a ditopic pyridyl ligand L with cis-protected Pd(II) metal centers. This results into a controllable ... -
Room temperature molecular up conversion in solution
(Springer Nature, 2016-06-15)[Abstract] Up conversion is an Anti-Stokes luminescent process by which photons of low energy are piled up to generate light at a higher energy. Here we show that the addition of fluoride anions to a D2O solution of a ... -
Sulphur-rich functionalized calix[4]arenes for selective complexation of Hg2+ over Cu2+, Zn2+ and Cd2+
(Royal Society of Chemistry, 2016-08-16)[Abstract] The syntheses of two new ligands based on a calix[4]arene scaffold in the cone conformation functionalized on the phenolic positions 1 and 3 by diethylthiophosphonates (L1) or tetra(tri)thioethyleneglycol (L2) ... -
Transient versus static electron spin relaxation in Mn2+ complexes relevant as MRI contrast agents
(American Chemical Society, 2016-08-18)[Abstract] The zero-field splitting (ZFS) parameters of the [Mn(EDTA)(H2O)]2–·2H2O and [Mn(MeNO2A)(H2O)]·2H2O systems were estimated by using DFT and ab initio CASSCF/NEVPT2 calculations (EDTA = 2,2′,2″,2‴-(ethane-1,2-di ... -
Unexpected Changes in the Population of Coordination Isomers for the Lanthanide Ion Complexes of DOTMA–Tetraglycinate
(American Chemical Society, 2016-09-19)[Abstract] Lanthanide complexes with DOTA–tetraglycinate (DOTA-(gly)4) heavily favor the square antiprismatic (SAP) coordination isomer in aqueous solution, a structural feature that has made them useful as water-based ... -
Water exchange rates and mechanisms in tetrahedral [Be(H2O)4]2+ and [Li(H2O)4]+ complexes using DFT methods and cluster‐continuum models
(Wiley, 2016-10-05)[Abstract] The water exchange reactions in aquated Li+ and Be2+ ions were investigated with density functional theory calculations performed using the [Li(H2O)4]+·14H2O and [Be(H2O)4]2+·8H2O systems and a cluster‐continuum ... -
The relationship between NMR chemical shifts of thermally polarized and hyperpolarized 89Y complexes and their solution structures
(Wiley, 2016-11-07)[Abstract] Recently developed dynamic nuclear polarization (DNP) technology offers the potential of increasing the NMR sensitivity of even rare nuclei for biological imaging applications. Hyperpolarized 89Y is an ideal ... -
Developing the family of picolinate ligands for Mn2+ complexation
(Royal Society of Chemistry, 2016-12-22)[Abstract] We have reported here a series of ligands containing pentadentate 6,6′-(azanediylbis(methylene))dipicolinic acid units that differ in the substituent present at the amine nitrogen atom (acetate: H3DPAAA; phenyl: ... -
Definition of the labile capping bond effect in lanthanide complexes
(Wiley, 2017-01-23)[Abstract] 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 ... -
Ditopic receptors containing urea groups for solvent extraction of Cu(II) salts
(Royal Society of Chemistry, 2017-02-15)[Abstract] The ditopic receptor L3 [1-(2-((7-(4-(tert-butyl)benzyl)-1,4,7,10-tetraazacyclododecan-1-yl)methyl)phenyl)-3-(3-nitrophenyl)urea] containing a macrocyclic cyclen unit for Cu(II)-coordination and a urea moiety ...
