| 摘要 |
PURPOSE:To prepare a 5-alkyluracil useful as a drug, in extremely high yield, in high quality, by heating 5-alkylorotic acid in sulfuric acid. CONSTITUTION:5-Alkylorotic acid of formula I (R is lower alkyl) is heated in sulfuric acid to obtain 5-alkyluracil of formula II, economically. The compound of formula I used as the raw material can be prepared from the compound of formula III in high yield by conventional method. The industrial-grade concentrated sulfuric acid can be used for the purpose. Although the amount of the sulfuric acid is not defined rigorously, 1-10pts.wt. of the acid is sufficient for 1pt.wt. of the compound of formula I . The proper reaction temperature is 150- 200 deg.C. The progress of the reaction can be clearly inspected by determining the amount of evolved carbon dioxide gas. |
