936360-80-4

823-96-1

1094070-46-8

Part C: 6-bromo-3-iodo-8-(methylthio)imidazo[1,2-A]pyrazine (45.6 g), tetrakis(triphenylphosphine)palladium (10.8 g), potassium carbonate (77.4 g), and trimethylcyclotriboroxane (46.9 g) from Part A were suspended in N,N-dimethylformamide (410 mL), and the reaction was heated at 105 °C under nitrogen protection overnight. After completion of the reaction, the reaction was cooled to room temperature, the reaction mixture was diluted with ethyl acetate (1 L), washed sequentially with saturated saline (2×500 mL), the organic phase was dried with anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography to afford 6-methyl-8-(methylthio)-imidazo[1,2-a]pyrazine as a light yellow solid (21.4 g, 64% yield).