反应详情

A solution of 5.40 g of 2-aminothiazole in 150 ml of tetrahydrofuran was combined at 20° C. with 8.75 g of 1,1'-carbonyldiimidazole and the mixture stirred for 30 minutes. The mixture was then raised within 20 minutes to a bath temperature of between 55 and 60° C. and a solution of 9.80 g of the product from stage 3 in 30 ml of tetrahydrofuran was added dropwise. A clear, red-brown solution was obtained, which was stirred for 60 hours at a temperature of between 55° C. and 60° C. Once the solvent had been removed by distillation, the residue was purified by passage through a silica gel column with ethyl acetate. 10.20 g of 2-propyl-2-(3-thiazol-2-ylureido)pentanoic acid ethyl ester (62% of th.) were obtained in the form of a yellowish oil.

1. temperatureThe mixture was then raised within 20 minutes to a bath temperature of between 55 and 60° C.
2. customA clear, red-brown solution was obtained
3. stirringwhich was stirred for 60 hours at a temperature of between 55° C. and 60° C
4. customOnce the solvent had been removed by distillation
5. customthe residue was purified by passage through a silica gel column with ethyl acetate