| 摘要 |
PURPOSE:To safely and readily obtain the subject compound useful as an intermediate for medicines in high yield without forming by-products, etc., and using dangerous concentrated sulfuric acid by heating orotic acid in water solvent. CONSTITUTION:Orotic acid is heated in water solvent, normally at 150-280 deg.C, preferably 200-260 deg.C under a pressure which may be ordinary or higher pressure to afford the objective compound. The reaction time is preferably 1-15hr. The amount of the water used as the solvent is normally 1-100 pts.wt. based on 1 pt.wt. orotic acid. The system before starting the reaction is at a pH within the range of 1-10, preferably 2-5. Various buffering aqueous solutions, such as ammonia or sulfuric acid, are used as the pH adjustor. After completing the reaction, the reaction solution is cooled to precipitate the formed uracil as crystals. Furthermore, the orotic acid is obtained by reacting thiourea with gamma,gamma-diacetoxyacetic acid in the presence of sodium ethoxide and oxidizing the resultant product. |
