20924-05-4

79-11-8

65-71-4

20924-05-4

5-Methyluracil (10.0 g, 79.3 mmol) was suspended in distilled water (150 mL). Aqueous potassium hydroxide solution (50 mL, 3.6 M) was slowly added to the suspension. The mixture was stirred at room temperature for 10 minutes until the solution gradually became clear. Subsequently, chloroacetic acid (15.0 g, 159 mmol) was added to the clarified solution. The reaction mixture was heated to reflux and kept for 90 minutes. Upon completion of the reaction, the solution was cooled to room temperature and acidified with concentrated hydrochloric acid to pH=3. The acidified solution was placed in a refrigerator at 4°C overnight to promote the formation of white crystalline precipitate. The white crystalline precipitate was collected by filtration and dried under vacuum using phosphorus pentoxide (P2O5), resulting in 4.5 g of thymine-1-acetic acid in 31% yield.