A solution of 4-amino-5-cyano-6-ethoxypicolinic acid (0.100 g) in N,N-dimethylformamide (2.5 mL) was treated with 1-ethyl-3-(3′-dimethylaminopropyl)carbodiimide hydrochloride (0.102 g), 1-hyroxybenzotriazole hydrate (0.0813 g), followed by diisopropylethylamine (0.252 mL) at room temperature. After stirring for 15 minutes, the compound prepared in Example 416 (0.116 g) was added. Stirring was continued overnight, the mixture diluted with water, organic layer separated and washed with brine, dried, evaporated in vacuo to a beige paste that was triturated in ether and solids collected by filtration (0.584 g) with the following physical data.
