The general procedure for the synthesis of 1-(2-aminothiazol-5-yl)ethanone from 2-bromo-3-oxobutanal and compound (CAS: 17356-08-0) was as follows: 2-bromoacetoacetaldehyde (5 g, 0.03 mol) prepared in Step II was dissolved in ethanol (50 mL). Thiourea (2.76 g, 0.03 mol) was added to this solution and the reaction mixture was stirred at room temperature for 24 hours, followed by heating and refluxing for 3 hours. After completion of the reaction, the mixture was cooled to room temperature and the resulting solid product was separated by filtration. The solid was washed with ethanol and dried under vacuum to afford 1-(2-amino-1,3-thiazol-5-yl)ethanone (P5) as a white solid (2.5 g, 40% yield).
