- Reaction of 6-Methylsulfonylpurine Riboside with Carbon Nucleophiles and the Synthesis of 6-Alkylpurine Nucleosides. (Nucleosides and Nucleotides. XXIX)
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Treatment of 6-methylsulfonyl-9-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)purine with ethyl acetoacetate and sodium hydride in tetrahydrofuran afforded, after deblocking, 6-ethoxycarbonylmethyl-9-β-D-ribofuranosylpurine.Similarly, replacement of the 6-methylsulfonyl moiety with other carbanions derived from diethyl malonate, ethyl cyanoacetate, malononitrile, nitromethane, and sodium cyanide gave the corresponding 6-C-substituted purine nucleosides.Most of these derivatives exist as the 6-(1H)-exomethylene tautomeric forms. 6-Ethoxycarbonylmethylpurine riboside was further converted to 6-methyl, ethyl, propyl, butyl, and pentyl-purine ribosides by decarboxylation or prior alkylation of the methylene group followed by de-carboxylation.This reaction sequence facilitated the preparation of hitherto almost inaccessible alkyl or C-substituted purine nucleosides.Keywords- nucleophilic aromatic substitution; carbon nucleophiles; purine nucleosides; UV; NMR; tautomerism
- Yamane, Akira,Matsuda, Akira,Ueda, Tohru
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p. 150 - 156
(2007/10/02)
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