Synthesis of Furo[2,3‐b]pyrazine Nucleoside Analogues with 1,2,3‐Triazole Linkage

Abstract

AbstractSonogashira coupling reaction with the readily available 1‐(4‐methoxybenzyl)‐3,5‐dichloropyrazin‐2(1H)‐ones was followed by mild silver‐catalyzed cyclization to provide the corresponding 2‐chlorofuro[2,3‐b]pyrazines in excellent yields. A second Sonogashira cross‐coupling reaction resulted in the formation of 2‐ethynylfuro[2,3‐b]pyrazines, which were coupled with D‐ribose and 2‐deoxy‐D‐ribose using a microwave‐assisted Cu(I)‐catalyzed Huisgen [2+3] dipolar cycloaddition reaction, to generate a small library of new nucleoside analogues.