反应详情

To 2-(3-Carboxy-acryloylamino)-4,5-dimethyl-thiophene-3-carboxylic acid ethyl ester (2.97 g, 10.0 mmol) in 50 mL of N,N-dimethyl-formamide was added N-hydroxy-benzotriazole (1.48 g, 11.0 mmol) and 1-[3-(dimethylamino) propyl]-3-ethyl-carbodiimide hydrochloride (2.88 g, 15.0 mmol). The reaction mixture was stirred at room temperature for 10 minutes and thiourea (0.84 g, 11.0 mmol) was added. The reaction mixture was stirred at room temperature for another 30 minutes and was heated at 60° C. for 12 hours. The reaction mixture was diluted with 250 mL of ethyl acetate and was washed with 100 mL of water and 100 mL of brine. The organic layer was collected, dried over sodium sulfate and concentrated. The residue was load on a 120 g silica gel column and purified by flash chromatography (eluted with a gradient of 0 to 10% ethyl acetate/hexanes). Ethyl 2-{[(2-amino-4-oxo-4,5-dihydro-1,3-thiazol-5-yl) acetyl]amino}-4,5-dimethylthiophene-3-carboxylate (1.80 g, 51% yield) was produced.

1. stirringThe reaction mixture was stirred at room temperature for another 30 minutes
2. temperaturewas heated at 60° C. for 12 hours
3. washwas washed with 100 mL of water and 100 mL of brine
4. customThe organic layer was collected
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated
7. custompurified by flash chromatography (
8. washeluted with a gradient of 0 to 10% ethyl acetate/hexanes)