Hydrochloric Acid → 5-Ureidomethyl-imidazo[5,1-b]thiazole

Temperature

80 °C

To 220 mg (1.42 mmol) of 5-aminomethylimidazo[5,1-b]-thiazole and 0.3 mg of ice were added 1 ml of ice-cooled water and 1 ml of 5N hydrochloric acid, and the mixture was stirred at 80° C. for 5 minutes. To this mixture was added 111 mg of sodium cyanate, and the resulting mixture was stirred at the temperature for 2 hours. 123 mg of sodium cyanate was further added to the mixture, and the resulting mixture was stirred for one hour. 122 mg of sodium cyanate was added again to the mixture, and the stirring was continued for 2 hours. The mixture was cooled to room temperature, and then made alkali by the addition of potassium carbonate. This mixture was washed with methylene chloride. MeOH was added to the aqueous layer, and the mixture was thoroughly stirred. Insoluble matters were removed by filtration. The filtrate was concentrated under reduced pressure, and then allowed to stand at 0° C. overnight. The crystals precipitated were collected by filtration to obtain 160 mg (yield 57%) of 5-ureidomethyl-imidazo[5,1-b]thiazole.

1. stirringthe resulting mixture was stirred at the temperature for 2 hours
2. stirringthe resulting mixture was stirred for one hour
3. waitthe stirring was continued for 2 hours
4. temperatureThe mixture was cooled to room temperature
5. washThis mixture was washed with methylene chloride
6. additionMeOH was added to the aqueous layer
7. stirringthe mixture was thoroughly stirred
8. customInsoluble matters were removed by filtration
9. concentrationThe filtrate was concentrated under reduced pressure
10. waitto stand at 0° C. overnight
11. customThe crystals precipitated
12. filtrationwere collected by filtration

ORD record

ord-15a2d75a265b45a0b4371aa0dc2c636b

Source dataset

uspto-grants-1997_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05663162