Thymine → 2-(5-Methyl-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-1-yl)acetic acid

This procedure is different from the literature synthesis, but is easier, gives higher yields, and leaves no unreacted thymine in the product. To a suspension of thymine (3, 40 g, 0.317 mol) and potassium carbonate (87.7 g, 0.634 mmol) in DMF (900 mL) was added methyl bromoacetate (30 mL, 0.317 mmol). The mixture was stirred vigorously overnight under nitrogen. The mixure was filtered and evaporated to dryness, in vacuo. The solid residue was treated with water (300 mL) and 4N hydrochloric acid (12 mL), stirred for 15 minutes at 0° C., filtered, and washed with water (2×75 mL). The precipitate was treated with water (120 mL) and 2N sodium hydroxide (60 mL), and was refluxed for 10 minutes. The mixture was cooled to 0C, filtered, and pure title compound was precipitated by the addition of 4N hydrochloric acid (70 mL). The yield after drying, in vacuo over sicapent was 37.1 g (64%). 1H-NMR: (90 MHz; DMSO-d6): 11.33 ppm (s, 1H, NH); 7.49 (d, J=0.92 Hz, 1H, ArH); 4.38 (s, 2H, CH2); 1.76 (d, J=0.92 Hz, T-CH3).

1. filtrationThe mixure was filtered
2. customevaporated to dryness, in vacuo
3. additionThe solid residue was treated with water (300 mL) and 4N hydrochloric acid (12 mL)
4. stirringstirred for 15 minutes at 0° C.
5. filtrationfiltered
6. washwashed with water (2×75 mL)
7. additionThe precipitate was treated with water (120 mL) and 2N sodium hydroxide (60 mL)
8. temperaturewas refluxed for 10 minutes
9. temperatureThe mixture was cooled to 0C
10. filtrationfiltered
11. custompure title compound was precipitated by the addition of 4N hydrochloric acid (70 mL)
12. customThe yield
13. customafter drying, in vacuo

ORD record

ord-2ebc36e9c98b4559b1811742a62b7894

Source dataset

uspto-grants-1998_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05766855