| Popis: |
According to the data of UV and NMR spectroscopy, 1- and 3-methylpyrimidin-4-ones and their 5-fluoro-substituted analogs in water and DMSO in the presence of bases undergo ring opening with formation of β-formylaminoacrylamide derivatives. The process involves attack by hydroxide ion on the C2 atom, and its rate in DMSO is higher than in water by three orders of magnitude. Ring opening in 1-methylpyrimidin-4-ones occurs more readily than in the corresponding 3-methyl isomers, while the acyclic products formed from 3-methylpyrimidin-4-ones in DMSO are more stable than those derived from 1-methylpyrimidin-4-ones. |
