In a sealed tube 3-cyclopropyl-1-(2-fluoro-4-iodophenyl)-6,8-dimethyl-2,4,7-trioxo-1,2,3,4,7,8-hexahydropyrido[2,3-d]pyrimidin-5-yl 4-methylbenzenesulfonate (4a) (0.5 g, 0.78 mmol), (3-aminophenyl)(azetidin-1-yl)methanone (intermediate 1) (0.27 g, 1.56 mmol) were taken to the mixture DMA (2 ml) and 2,6-lutidine (0.42 mg, 3.92 mmol) were added and the mixture was heated at 130° C. for 16 hr under nitrogen atmosphere. After completion of the reaction, the reaction mixture was poured into ice cold water, the separated solid was filtered off and washed with water and dried under vacuum. The crude solid was purified by column chromatography to yield the titled compound (0.11 g).
