A solution of (3R)-1-(2-chloropyrimidin-4-yl)-3-ethyl-2-oxopyrrolidine-3-carbonitrile (51 mg), 4-amino-N-methylbenzamide (32 mg) and acetic acid (12 μL) in 2-propanol (1 mL) was stirred in a microwave reactor at 150° C. for 1 hr. The reaction mixture was concentrated under reduced pressure, saturated aqueous sodium hydrogen carbonate solution was added thereto, and the mixture was extracted with ethyl acetate. The extract was washed with saturated brine, and dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/ethyl acetate), and recrystallized (hexane/ethyl acetate) to give the title compound (31 mg).
