Transformation of 1-methyluracils and uridine to respective, 4-substituted pyrimdin-2(1H)-ones via pyridinium salts

Abstract

1-Methyluracil and 1-methylthymine are converted into N-(1-methylpyrimidin-2-one-4-yl)- and N-(1-dimethylpyrimidin-2-one-4-yl)-pyridinium chlorides, respectively. The pyrimidinyl-pyridinium salts were then reacted with various nucleophiles under very mild conditions to give high yields of the desired 4-substituted pyrimidinones. In a similar manner 2′,3′,5′-tri-O-acetyluridine is efficiently converted into new 4-substituted pyrimidinone nucleosides.