Synthesis and properties of a new class of nucleosides with spin source.
Novel spin-labeled ribonucleosides 1-5 were synthesized to investigate stability and behavior of N-tert-butyl aminoxyl radical on nucleobase. Site selective lithiation of tri-O-protected ribonucleosides followed by the reaction with 2-methyl-2-nitrosopropane (MNP) resulted in introduction of N-tert-butylhydroxylamino group into various positions of purine or pyrimidine nucleus. Oxidation of the obtained hydroxylamines with Ag2O led to formation of 1-5. EPR study showed that the unpaired electron of the aminoxyl radical was delocalized into the nucleobase and hyperfine structures were dependent on the position of the radical.
Aso
M
M
Graduate School of Pharmaceutical Sciences, Kyushu University, Midashi, Higashiku, Fukuoka 812-8582, Japan.
Ikeno
T
T
Kaneko
T
T
Koga
N
N
Suemune
H
H
D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D009705:Nucleosides / Q000138:chemical synthesis* / Q000737:chemistry*; D011687:Purines / Q000138:chemical synthesis / Q000737:chemistry; D011743:Pyrimidines / Q000138:chemical synthesis / Q000737:chemistry; D013113:Spin Labels / Q000138:chemical synthesis*
D005609:Free Radicals; D009705:Nucleosides; D011687:Purines; D011743:Pyrimidines; D013113:Spin Labels