5-chloro-1,3-dimethylpyrido[2,3-{d}]pyrimidine-2,4(1{H},3{H})-dione synthesis

Yield:112734-83-5 79%

Reaction Conditions:

with trichlorophosphate in water;N,N-dimethyl-formamide;

Steps:

1.1 EXAMPLE 1

(1) 5.92 g of 5-acetyl-6-amino-1,3-dimethyluracil and 7.34 g of phosphorus oxychloride were added to 100 ml of DMF. The solution was heated for 2 hr at 60° C. and the solvent was distilled off under reduced pressure After adding water to the residue, the resulting crude crystals were separated from the solution by filtration and recrystallized from ethyl acetate to give 5.34 g of 5-chloro-1,3-dimethylpyrido[2,3-d]pyrimidine-2,4-dione (Compound 1). Yield: 79% m.p.: 175°-177 ° C. NMR(DMSO-d₆): δ=3.38(3H,s), 3.55(3H,s), 7.40(1H,d,J=5 Hz), 8.55(1H,d,J=5 Hz)

References:

US4808587,1989,A