反应详情

Ethoxycarbonyl isothiocyanate (0.656 ml, 5.61 mmol) is added dropwise to a stirred suspension of 3-(5-amino-[1,3,4]thiadiazol-2-yl)-propionic acid methyl ester (56a) in dichloromethane (30 ml). The reaction is at room temperature for 18 hours. After removing the solvent, aqueous sodium hydroxide (2M, 10 ml) is added and the stirred mixture is heated at reflux for 3 hours. The solution is allowed to cool to room temperature and brought to pH 3 by the addition of 6M aqueous HCl. The titled compound which precipitates is removed by filtration, washed with ethyl acetate and dried in vacuo.

1. customAfter removing the solvent, aqueous sodium hydroxide (2M, 10 ml)
2. additionis added
3. temperaturethe stirred mixture is heated
4. temperatureat reflux for 3 hours
5. additionbrought to pH 3 by the addition of 6M aqueous HCl
6. customThe titled compound which precipitates
7. customis removed by filtration
8. washwashed with ethyl acetate
9. customdried in vacuo