Nucleoside synthesis from 3-alkylated sugars: role of 3β-oxy substituents in directing nucleoside formation
作者:Sk. Sahabuddin、Ramprasad Ghosh、Basudeb Achari、Sukhendu B. Mandal
DOI:10.1039/b514028e
日期:——
protocol, reaction of persilylated uracil with xylofuranose derivatives having 3beta-oxy-3alpha-alkyl substitution produced both alpha- and beta-nucleosides. Only the beta-nucleosides were formed from substrates having the reverse stereochemistry at C-3 or lacking the 3-alkyl substituent. Participation of the 3beta-oxy substituent in stabilizing the incipient C-1 carboniumion (or oxonium ion) intermediate