N-(3-Aminopropyl)morpholine → 6-(2,6-dichlorophenyl)-8-methyl-2-{[3-(morpholin-4-yl)propyl]amino}-7H,8H-pyrido[2,3-d]pyrimidin-7-one

A mixture of 0.165 g (0.47 mmol) of 6-(2,6-dichlorophenyl)-8-methyl-2-methylsulfanyl-8H-pyrido[2,3-d]pyrimidin-7-one of Example 37, 1.00 g (6.90 mmol) of N-(3-aminopropyl)morpholine and 0.5 mL of dimethylformamide was heated with stirring in a 125° C. oil bath. After 2 minutes, solution was complete. After 1.5 hours, the excess amine and dimethylformamide were evaporated at reduced pressure and the residue was triturated with 5 mL of water. The gum was dissolved in 25 mL of ethyl acetate, and the solution was washed with 2×5 mL of water, dried (potassium carbonate), and concentrated. Upon dissolution in 5 mL of ether, crystals of pure product separated; wt 0.101 g; mp 140°-142° C.