A solution of 1,4-dihydro-2-methoxy-6-methyl-4-(3-nitrophenyl)-5-pyrimidinecarboxylic acid, 1-methylethyl ester (3.34 g, 10 mmol; see Example 2A) and dry triethylamine (6.3 ml, 45 mmol) in dichloromethane (10 ml) in an ice bath under argon was treated dropwise via syringe with 1.3M phosgene in benzene solution (9.2 ml, 12 mmol). The resulting mixture was stirred in the bath for 20 hours. After cooling to 0° C. with a fresh ice bath, the mixture was treated with benzylmethylamine (1.95 ml, 15 mmol) and stirred at room temperature overnight. The reaction was then diluted with dichloromethane and washed with water, saturated sodium chloride, dried (potassium carbonate) and evaporated. The residue was passed through a short pad of silica, eluting with 20% acetone/hexanes. The fractions were combined evaporated and triturated with isopropyl ether to give white crystals (4.11 g), melting point 145°-146° C. (softens 140° C.).
