反应详情

To a stirred suspension of 1-[4-(1-amino-2-hydroxy-ethyl)-phenyl]-3-(4-chloro-phenyl)-urea (160 mg) and sodium acetate (129 mg) in methanol (8 ml) was added dropwise a solution of cyanogen bromide (72 mg) in methanol (0.5 ml). The resulting pale yellow solution was then stirred at room temperature for 16 h. Aqueous ammonia solution (0.4 ml, 25%) was added dropwise and stirring was continued for a further hour. The mixture was then concentrated in vacuo and the residue was purified by column chromatography (Isolute® Flash-NH2 from Separtis; gradient: heptane/dichloromethane/methanol) to give (RS)-1-[4-(2-amino-4,5-dihydro-oxazol-4-yl)-phenyl]-3-(4-chloro-phenyl)-urea (91 mg, 53%) as a white solid. MS (ISP): 333.2 ([{37Cl}M+H]+), 331.1 ([{35Cl}M+H]+).

1. stirringstirring
2. waitwas continued for a further hour
3. concentrationThe mixture was then concentrated in vacuo
4. customthe residue was purified by column chromatography (Isolute® Flash-NH2 from Separtis; gradient: heptane/dichloromethane/methanol)