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The population of SAP and TSAP isomers in cyclen-based lanthanide(III) chelates is substantially affected by solvent.

ABSTRACT: The square antiprism/twisted square antiprism ratio in LnDOTA-tetraamide chelates is a critical parameter in governing water-exchange kinetics and ultimately the utility of a chelate as a PARACEST MRI contrast agent. In LnDOTA-tetraamide chelates with tertiary amides, this ratio and the rate of interconversion between these two structural isomers are found to be dramatically dependent upon the solvent and possibly other local environmental factors.

SUBMITTER: Miller KJ

PROVIDER: S-EPMC3033777 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature

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The population of SAP and TSAP isomers in cyclen-based lanthanide(III) chelates is substantially affected by solvent.

Miller Kyle J KJ Saherwala Ali A AA Webber Benjamin C BC Wu Yunkou Y Sherry A Dean AD Woods Mark M

Inorganic chemistry 20101001 19

The square antiprism/twisted square antiprism ratio in LnDOTA-tetraamide chelates is a critical parameter in governing water-exchange kinetics and ultimately the utility of a chelate as a PARACEST MRI contrast agent. In LnDOTA-tetraamide chelates with tertiary amides, this ratio and the rate of interconversion between these two structural isomers are found to be dramatically dependent upon the solvent and possibly other local environmental factors. ...[more]

PMID: 20812752

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