Abstract
Mizoribine® (4-carbamoyl-1-β-D-ribofuranosylimidazolium-5-olate)(13β) and its 4-cyano analogue (20) were synthesized by formation of a malonamide from 2,3-isopropylidene-D-ribosylamine and a malonic acid derivative followed by amination, cyclisation and deprotection steps.