FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W2063698049> ?p ?o ?g. }

• W2063698049 endingPage "1404" @default.
• W2063698049 startingPage "1394" @default.
• W2063698049 abstract "Eu(II) complexes are potential candidates for pO(2)-responsive contrast agents in magnetic resonance imaging. In this regard, we have characterized two novel macrocyclic Eu(II) chelates, [Eu(II)(DOTA)(H(2)O)](2-) and [Eu(II)(TETA)](2-) (H(4)DOTA=1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid, H(4)TETA=1,4,8,11-tetraazacyclotetradecane-1,4,8,11-tetraacetic acid) in terms of redox and thermodynamic complex stability, proton relaxivity, water exchange, rotation and electron spin relaxation. Additionally, solid-state structures were determined for the Sr(II) analogues. They revealed no inner-sphere water in the TETA and one inner-sphere water molecule in the DOTA complex. This hydration pattern is retained in solution, as the (17)O chemical shifts and (1)H relaxation rates proved for the corresponding Eu(II) compounds. The thermodynamic complex stability, determined from the formal redox potential and by pH potentiometry, of [Eu(II)(DOTA)(H(2)O)](2-) (lg K(Eu(II))=16.75) is the highest among all known Eu(II) complexes, whereas the redox stabilities of both [Eu(II)(DOTA)(H(2)O)](2-) and [Eu(II)(TETA)](2-) are inferior to that of 18-membered macrocyclic Eu(II) chelates. Variable-temperature (17)O NMR, NMRD and EPR studies yielded the rates of water exchange, rotation and electron spin relaxation. Water exchange on [Eu(II)(DOTA)(H(2)O)](2-) is remarkably fast (k298(ex)=2.5 x 10(9) s(-1)). The near zero activation volume (DeltaV++ =+0.1+/-1.0 cm(3) mol(-1)), determined by variable-pressure (17)O NMR spectroscopy, points to an interchange mechanism. The fast water exchange can be related to the low charge density on Eu(II), to an unexpectedly long M-O(water) distance (2.85 A) and to the consequent interchange mechanism. Electron spin relaxation is considerably slower on [Eu(II)(DOTA)(H(2)O)](2-) than on the linear [Eu(II)(DTPA)(H(2)O)](3-) (H(5)DTPA=diethylenetriaminepentaacetic acid), and this difference is responsible for its 25 percent higher proton relaxivity (r(1)=4.32 mM(-1) s(-1) for [Eu(II)(DOTA)(H(2)O)](2-) versus 3.49 mM(-1) s(-1) for [Eu(II)(DTPA)(H(2)O)](3-); 20 MHz, 298 K)." @default.
• W2063698049 created "2016-06-24" @default.
• W2063698049 creator A5004194022 @default.
• W2063698049 creator A5010918971 @default.
• W2063698049 creator A5011927356 @default.
• W2063698049 creator A5033332794 @default.
• W2063698049 creator A5086550863 @default.
• W2063698049 creator A5087099155 @default.
• W2063698049 date "2003-03-11" @default.
• W2063698049 modified "2023-10-14" @default.
• W2063698049 title "Novel Macrocyclic EuII Complexes: Fast Water Exchange Related to an Extreme MOwater Distance" @default.
• W2063698049 cites W169468839 @default.
• W2063698049 cites W1972763884 @default.
• W2063698049 cites W1972920331 @default.
• W2063698049 cites W1978567151 @default.
• W2063698049 cites W1984610316 @default.
• W2063698049 cites W1984665417 @default.
• W2063698049 cites W1993216857 @default.
• W2063698049 cites W2001302061 @default.
• W2063698049 cites W2002972210 @default.
• W2063698049 cites W2005056527 @default.
• W2063698049 cites W2006324160 @default.
• W2063698049 cites W2008407458 @default.
• W2063698049 cites W2009219986 @default.
• W2063698049 cites W2016046208 @default.
• W2063698049 cites W2020074807 @default.
• W2063698049 cites W2028190440 @default.
• W2063698049 cites W2031738079 @default.
• W2063698049 cites W2042149602 @default.
• W2063698049 cites W2057436245 @default.
• W2063698049 cites W2067957356 @default.
• W2063698049 cites W2070881094 @default.
• W2063698049 cites W2074066467 @default.
• W2063698049 cites W2076283593 @default.
• W2063698049 cites W2077821054 @default.
• W2063698049 cites W2088184108 @default.
• W2063698049 cites W2089004748 @default.
• W2063698049 cites W2091566149 @default.
• W2063698049 cites W2093602491 @default.
• W2063698049 cites W2094051292 @default.
• W2063698049 cites W2117405777 @default.
• W2063698049 cites W2138118849 @default.
• W2063698049 cites W2140613515 @default.
• W2063698049 cites W2167590372 @default.
• W2063698049 cites W2950142958 @default.
• W2063698049 cites W3003680839 @default.
• W2063698049 cites W4246334022 @default.
• W2063698049 cites W619105361 @default.
• W2063698049 doi "https://doi.org/10.1002/chem.200390159" @default.
• W2063698049 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/12645029" @default.
• W2063698049 hasPublicationYear "2003" @default.
• W2063698049 type Work @default.
• W2063698049 sameAs 2063698049 @default.
• W2063698049 citedByCount "67" @default.
• W2063698049 countsByYear W20636980492012 @default.
• W2063698049 countsByYear W20636980492013 @default.
• W2063698049 countsByYear W20636980492015 @default.
• W2063698049 countsByYear W20636980492016 @default.
• W2063698049 countsByYear W20636980492017 @default.
• W2063698049 countsByYear W20636980492018 @default.
• W2063698049 countsByYear W20636980492019 @default.
• W2063698049 countsByYear W20636980492020 @default.
• W2063698049 countsByYear W20636980492021 @default.
• W2063698049 countsByYear W20636980492022 @default.
• W2063698049 countsByYear W20636980492023 @default.
• W2063698049 crossrefType "journal-article" @default.
• W2063698049 hasAuthorship W2063698049A5004194022 @default.
• W2063698049 hasAuthorship W2063698049A5010918971 @default.
• W2063698049 hasAuthorship W2063698049A5011927356 @default.
• W2063698049 hasAuthorship W2063698049A5033332794 @default.
• W2063698049 hasAuthorship W2063698049A5086550863 @default.
• W2063698049 hasAuthorship W2063698049A5087099155 @default.
• W2063698049 hasConcept C11111787 @default.
• W2063698049 hasConcept C115624301 @default.
• W2063698049 hasConcept C121332964 @default.
• W2063698049 hasConcept C145148216 @default.
• W2063698049 hasConcept C15744967 @default.
• W2063698049 hasConcept C178790620 @default.
• W2063698049 hasConcept C179104552 @default.
• W2063698049 hasConcept C185592680 @default.
• W2063698049 hasConcept C186399102 @default.
• W2063698049 hasConcept C187961010 @default.
• W2063698049 hasConcept C197404232 @default.
• W2063698049 hasConcept C2776029896 @default.
• W2063698049 hasConcept C2779931791 @default.
• W2063698049 hasConcept C35818081 @default.
• W2063698049 hasConcept C46141821 @default.
• W2063698049 hasConcept C54516573 @default.
• W2063698049 hasConcept C55904794 @default.
• W2063698049 hasConcept C62520636 @default.
• W2063698049 hasConcept C77805123 @default.
• W2063698049 hasConcept C8010536 @default.
• W2063698049 hasConceptScore W2063698049C11111787 @default.
• W2063698049 hasConceptScore W2063698049C115624301 @default.
• W2063698049 hasConceptScore W2063698049C121332964 @default.
• W2063698049 hasConceptScore W2063698049C145148216 @default.
• W2063698049 hasConceptScore W2063698049C15744967 @default.
• W2063698049 hasConceptScore W2063698049C178790620 @default.

• next