2-(5-Chloro-pyridin-2-ylamino)-thiazole-5-carboxylic acid ethyl ester (1.0 g) was prepared according to General Procedure C using (5-chloro-pyridin-2-yl)-thiourea (938 mg) and 2-chloro-3-oxo-propionic acid ethyl ester (900 mg) in benzene (15 mL). The crude product was washed with dichloromethane:hexane (1:1, 200 mL) solution to give a substantially pure product. 2-(5-Chloro-pyridin-2-ylamino)-thiazole-5-carboxylic acid (663 mg) was prepared according to General Procedure C using 2-(5-Chloro-pyridin-2-ylamino)-thiazole-5-carboxylic acid ethyl ester (1.0 g) in methanol:tetrahydrofuran:2N NaOH (1:1:1, 6 mL). The crude product was used in a subsequent step without further purification.
