To N-(4-(3-((trans)-4-hydroxycyclohexyl)-8-methylimidazo[1,5-a]pyrazin-1-yl)-2-methoxyphenyl)-4-methoxy-1-methyl-1H-indole-2-carboxamide (0.037 mmol, 20 mg) and N,N-dimethylpyridin-4-amine (7.41 μmol, 0.906 mg) in dichloromethane (2 ml) was added cyclopentyl isocyanate (0.185 mmol, 20.60 mg) and the mixture was stirred at room temperature overnight. Then pyridine (2 ml) was added and the mixture was stirred overnight at 90° C. The reaction mixture was diluted with ethyl acetate and the obtained suspension was filtered. The filtrate was purified by column chromatography (silica gel; dichloromethane with gradient 0 to 5% methanol) to give (trans)-4-(1-(3-methoxy-4-(4-methoxy-1-methyl-1H-indole-2-carboxamido)phenyl)-8-methylimidazo[1,5-a]pyrazin-3-yl)cyclohexyl cyclopentylcarbamate (6 mg).
