Linked Life Data

17979790

Source:http://linkedlifedata.com/resource/pubmed/id/17979790

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
2007-11-5
pubmed:abstractText
Fluorine-18 ((18)F, beta(+); 96.7%, T(1/2)=109.8 min) is of considerable importance for developing positron emission tomography (PET) ligands for imaging receptor, enzyme, gene expression etc. in brain, tumor, myocardium and other regions or organs due to its optimal decay characteristics. To synthesize (18)F-labeled PET ligands, reliable labeling techniques inserting (18)F into a target molecule are necessary. [(18)F]Fluoroalkylation is a useful way of introducing (18)F into target molecules containing amino, phenol, thiophenol, and amide functional groups. Here, we review the preparation, reactivity and application of [(18)F]fluoroalkyl agents for the development of (18)F-labeled PET ligands in molecular imaging. [(18)F]Fluoroalkyl agents have been synthesized by reacting [(18)F]F(-) with the corresponding alkyl derivatives containing halogen and sulfonate as leaving groups. After the fluorination reaction, the radiolabeled products with relatively low boiling points were distilled from the reaction mixtures, sometimes added by Sep-Pak or gas chromatography separation. The [(18)F]fluoromethyl agents have high reactivity with nucleophilic substrates, but many [(18)F]fluoromethylated compounds are in vitro unstable. To increase the efficiency of [(18)F]fluoroethylation, [(18)F]FCH2CH2Br, the most frequently used [(18)F]fluoroethyl agent, was converted into [(18)F]FCH2CH2I or [(18)F]FCH2CH2OTf in situ. Most [(18)F]fluoromethylated ligands were found to be in vivo unstable due to defluorination. Deuterium substitution for the fluoromethyl group reduced defluorination to an extent. A number of [(18)F]fluoroethylated PET ligands have been developed for animal evaluation and clinical investigation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1873-4294
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
7
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1817-28
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
[18F]Fluoroalkyl agents: synthesis, reactivity and application for development of PET ligands in molecular imaging.
pubmed:affiliation
Radiochemistry Section, Department of Molecular Probes, Molecular Imaging Center, National Institute of Radiological Sciences, Chiba, Japan. zhang@nirs.go.jp
pubmed:publicationType
Journal Article, Review