To a solution of 1-(4,6-dibromo-thiazolo[5,4-c]pyridin-2-yl)-3-ethyl-urea (0.06 g, 0.16 mmol) in DMF (3 mL) was added 2-(tributylstannyl)pyrazine (0.10 mL, 0.32 mmol) at room temperature under nitrogen atmosphere. The reaction mixture was degassed by bubbling nitrogen for 10-15 min followed by addition of Pd(PPh3)4 (0.018 g, 0.015 mmol). The resulting solution was again degassed for 15-20 min followed by heating up to 95° C. overnight. After completion of reaction (TLC monitoring), the reaction mixture was cooled, added water (30 mL) and extracted with ethyl acetate (3×20 mL). The combined organics was dried over Na2SO4 and evaporated to dryness under high vacuum. The crude residue was purified over silica-gel (100-200 M, 2% MeOH-DCM) to get the desired product (0.004 g, 7%).
