868-59-7

78-98-8

160060-21-9

GENERAL METHOD: Sodium bicarbonate (0.68 g, 8.1 mmol) was added to a solution of ethyl L-cysteinate hydrochloride (1 g, 5.4 mmol) in water (25 mL) and stirred until completely dissolved. Subsequently, a solution of acetone aldehyde (0.43 g, 5.9 mmol) in ethanol (25 mL) was added slowly and dropwise to the above reaction mixture. The reaction system was heated to 60 °C and the reaction was continuously stirred for 8 hours. The consumption of raw materials was monitored by thin layer chromatography (TLC) during the reaction. After completion of the reaction, the reaction mixture was concentrated under reduced pressure to remove the solvent. The reaction mixture was extracted with dichloromethane (2 x 30 mL) and the organic phases were combined. The organic phase was dried over anhydrous sodium sulfate and concentrated under reduced pressure to half the original volume (about 30 mL). To the concentrated solution, iodobenzene diacetate (3.65 g, 11.3 mmol) was added and the reaction mixture was heated to 40 °C and stirred for 4 hours. The reaction progress was monitored by TLC. At the end of the reaction, the solvent was removed by evaporation under reduced pressure. The crude product was purified by column chromatography (eluent: 5% ethyl acetate/hexane) to afford the target product ethyl 2-acetylthiazole-4-carboxylate.