Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1989-7-11
pubmed:abstractText
A synthesis of 5-bromo- and 5-iodo-1-(2-fluoro-2-deoxy-beta-D-ribofuranosyl)uracil (3 and 4) and their 5-82Br and 5-131I analogues has been developed. The tissue distribution of the radiolabeled compounds in BDF1 mice bearing Lewis lung tumors has been investigated. After injection of the radiolabeled analogues of compounds 3 and 4 there was a rapid initial excretion of activity. Compound 3 was excreted unchanged in the urine. Residual activity in mice after 4 h showed a distribution characteristic of bromide (Br-). Compound 4 was excreted mainly as unchanged starting material with increasing amounts of iodide (I-) detected at later time periods, in addition to 5-iodouridine and unidentified metabolites at shorter time periods. Both 3 and 4 demonstrated a remarkable in vivo stability relative to related 5-substituted nucleosides that do not contain the 2'-fluoro group. The tumor uptake was minimal, with only the 5-bromo analogue demonstrating a slight elevation in tumor to blood ratios relative to other tissues. Compounds 3 and 4 were shown to compete with thymidine for the same binding site in the transport of nucleosides across the cell membrane in mouse erythrocytes. The inhibition constants (Ki) show that the compounds were weak competitors of thymidine binding to pyrimidine nucleoside transporter compared to physiological nucleosides. Other evidence indicates that compounds 3 and 4 are not substrates for mammalian kinase enzymes.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0022-2623
pubmed:author
pubmed:issnType
Print
pubmed:volume
32
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1289-94
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Synthesis and tumor uptake of 5-82Br- and 5-131I-labeled 5-halo-1-(2-fluoro-2-deoxy-beta-D-ribofuranosyl)uracils.
pubmed:affiliation
Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Canada.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't