Methylmalonic Acid → 3-Cyclopropyl-1-(2-fluoro-4-iodophenyl)-5-hydroxy-6,8-dimethylpyrido(2,3-d)pyrimidine-2,4,7(1H,3H,8H)-trione

Participants

Reaction Conditions

Reaction Steps

To a 2:1 mixture (34.6 g) of 3-cyclopropyl-1-(2-fluoro-4-iodophenyl)-6-methylamino-1H-pyrimidine-2,4-dione 52 and 1-cyclopropyl-3-(2-fluoro-4-iodo-phenyl)6-methylamino-1H-pyrimidine-2,4-dione 53 obtained in Step 4, and 2-methylmalonic acid 54 (10.2 g) was added acetic anhydride (173 ml), and the mixture was stirred at 100° C. for 2 hrs. After allowing to cool to room temperature, the reaction mixture was concentrated under reduced pressure. Acetone (104 ml) was added to the residue, and the mixture was stirred with heating under reflux for 30 min. After allowing to cool to room temperature, the precipitated crystals were collected by filtration and dried to give 3-cyclopropyl-1-(2-fluoro-4-iodophenyl)-5-hydroxy-6,8-dimethyl-1H,8H-pyrido[2,3-d]pyrimidine-2,4,7-trione 55 (15.1 g, yield from 48, 21%) as colorless crystals.

Provenance & Evidence