Abstract:

α-Nucleoside is a kind of potential antiviral and antitumor agent, and of great interest in antisense and template directed reaction. β-Altropyranosyl-nucleosides have been synthesized and the properties of their oligo-nucleotides have been studied by Eshenmoser^[1]. But it is very difficult to synthesize the α-anomer, because the direct coupling reaction leads to the β-anomer and the cyanamide route is not suitable due to the trans-configuration of 1,2-dihydroxyl groups in α-altrose. In order to resolve this problem, α-2, 1'-anhydroglucopyranosyluridine was synthesized by cyanamide route and it was hydrolyzed to title compound in good yield with 2',3'-configuration reversion.