Imidazole → HCID 54312726, compound

Temperature

0 °C

An amount of 3.84 g (30 mmol) of 2-thiouracil was suspended in 75 ml of methylene chloride, was added to 17.8 ml (72 mmol) of bis(trimethylsilyl)acetamide and 7.2 g (45 mmol) of (2-acetoxyethoxy)methyl acetate and allowed to react at room temperature for 20 minutes. Then, the reaction solution was cooled to 0° C. and added to 4.5 ml (45 mmol) of stannic chloride. After the temperature of the solution had risen to room temperature, the solution was left to react overnight and then added to ice and sodium bicarbonate. After filtering off the deposited solid, the reaction solution was distributed between methylene chloride and aqueous layers. The methylene chloride layer was concentrated to dryness, and the residue was dissolved in a small amount of chloroform, adsorbed on a silica gel column and eluted with 2.5% methanol/chloroform. The eluate was concentrated, and the residue so obtained was dissolved in 5 ml of ethanol, was added to 5 ml of 1N sodium hydroxide aqueous solution and allowed to react at room temperature for 10 minutes. After the reaction, it was neutralized with H+ type cation-exchange resin (Dowex-50). Then, after the removal of the resin by filtration, the reaction solution is concentrated to dryness. The residue was dissolved in 15 ml of dimethylformamide, to this solution 600 mg (4 mmol) of t-butyldimethylsilyl chloride and 270 mg (4 mmol) of imidazole was added and the reaction mixture was allowed to react at room temperature for one hour. Then, the reaction solution was added to 50 ml of water, and the deposited solid was recovered by filtration and dried. The resultant product was recrystallized from toluene/hexane to obtain 716 mg of 1-[(2-t-butyldimethylsilyloxyethoxy)methyl]-2-thiouracil (Yield: 7.5%).

1. customto react at room temperature for 20 minutes
2. customhad risen to room temperature
3. waitthe solution was left
4. customto react overnight
5. filtrationAfter filtering off the deposited solid
6. concentrationThe methylene chloride layer was concentrated to dryness
7. dissolutionthe residue was dissolved in a small amount of chloroform
8. washeluted with 2.5% methanol/chloroform
9. concentrationThe eluate was concentrated
10. customthe residue so obtained
11. customto react at room temperature for 10 minutes
12. customAfter the reaction, it
13. customThen, after the removal of the resin
14. filtrationby filtration
15. concentrationthe reaction solution is concentrated to dryness
16. additionwas added
17. customto react at room temperature for one hour
18. filtrationthe deposited solid was recovered by filtration
19. customdried
20. customThe resultant product was recrystallized from toluene/hexane

ORD record

ord-ed2016a834224447ae1acb94b44442c7

Source dataset

uspto-grants-1992_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05112835