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Toward hyperpolarized molecular imaging of HIV: synthesis and longitudinal relaxation properties of (15) N-Azidothymidine.

ABSTRACT: Previously unreported (15) N labeled Azidothymidine (AZT) was prepared as an equimolar mixture of two isotopomers: 1-(15) N-AZT and 3-(15) N-AZT. Polarization decay of (15) N NMR signal was studied in high (9.4?T) and low (~50?mT) magnetic fields. (15) N T1 values were 45?±?5?s (1-(15) N-AZT) and 37?±?2?s (3-(15) N-AZT) at 9.4?T, and 140?±?16?s (3-(15) N-AZT) at 50?mT. (15) N-AZT can be potentially (15) N hyperpolarized by several methods. These sufficiently long (15) N-AZT T1 values potentially enable hyperpolarized in vivo imaging of (15) N-AZT, because of the known favorable efficient (i.e., of the time scale shorter than the longest reported here (15) N T1 ) kinetics of uptake of injected AZT. Therefore, 3-(15) N-AZT can be potentially used for HIV molecular imaging using hyperpolarized magnetic resonance imaging.

SUBMITTER: Shchepin RV

PROVIDER: S-EPMC4287256 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Toward hyperpolarized molecular imaging of HIV: synthesis and longitudinal relaxation properties of (15) N-Azidothymidine.

Shchepin Roman V RV Chekmenev Eduard Y EY

Journal of labelled compounds & radiopharmaceuticals 20140825 10

Previously unreported (15) N labeled Azidothymidine (AZT) was prepared as an equimolar mixture of two isotopomers: 1-(15) N-AZT and 3-(15) N-AZT. Polarization decay of (15) N NMR signal was studied in high (9.4 T) and low (~50 mT) magnetic fields. (15) N T1 values were 45 ± 5 s (1-(15) N-AZT) and 37 ± 2 s (3-(15) N-AZT) at 9.4 T, and 140 ± 16 s (3-(15) N-AZT) at 50 mT. (15) N-AZT can be potentially (15) N hyperpolarized by several methods. These sufficiently long (15) N-AZT T1 values potentially ...[more]

PMID: 25156931

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