To a solution of 1-(4,6-dibromo-thiazolo[5,4-c]pyridin-2-yl)-3-ethyl-urea (0.07 g, 0.17 mmol) in DMF:H2O (3:1, 4 mL) was added pyridine-3-boronic acid (0.08 g, 0.68 mmol) and potassium phosphate tribasic (0.09 g, 0.43 mmol) at room temperature under nitrogen atmosphere. The reaction mixture was degassed by bubbling nitrogen for 15-20 min followed by addition of Pd(PPh3)4 (0.04 g, 0.07 mmol). The resulting solution was again degassed for 15-20 min followed by heating up to 90° C. overnight. After completion of reaction (TLC monitoring), the reaction mixture was cooled, water was added and extracted with ethyl acetate, dried over Na2SO4 and evaporated to dryness under high vacuum. The crude residue was purified by Prep HPLC to get the desired product (0.015 g, 23%).
