2-(5-Chloro-pyridin-2-ylamino)-thiazole-4-carboxylic acid ethyl ester (1.0 g) was prepared according to General Procedure C using (5-chloro-pyridin-2-yl)-thiourea (1.0 g) and 3-bromo-2-oxo-propionic acid ethyl ester (1.07 g) in methanol (15 mL). The crude product was washed with a dichloromethane:hexane (1:1, 200 mL) solution to give a substantially pure product. 2-(5-Chloro-pyridin-2-ylamino)-thiazole-4-carboxylic acid (76 mg) was prepared according to General Procedure C using 2-(5-chloro-pyridin-2-ylamino)-thiazole-4-carboxylic acid ethyl ester (100 mg) in methanol:tetrahydrofuran (1:1, 2 mL) and 2N sodium hydroxide in water (0.5 mL). The crude product was used in subsequent steps without further purification.
