[C:1]([N:8]1C=CN=C1)([N:3]1C=CN=C1)=O.[F:13][C:14]([F:25])([F:24])[C:15]1[CH:20]=[CH:19][N:18]=[CH:17][C:16]=1[C:21]([OH:23])=[O:22].[CH2:26]([O:28][C:29](NC=NO)=[O:30])[CH3:27]>O1CCOCC1>[NH2:8][C:1](=[N:3][O:22][C:21]([C:16]1[CH:17]=[N:18][CH:19]=[CH:20][C:15]=1[C:14]([F:13])([F:24])[F:25])=[O:23])[C:29]([O:28][CH2:26][CH3:27])=[O:30]17.3 g of carbonyldiimidazole are initially charged in 200 ml of 1,4-dioxane and, a little at a time, admixed with 20 g of 4-trifluoromethyl-3-pyridinecarboxylic acid. The mixture is stirred at room temperature for 1 h and subsequently heated to 45° C. for 2 h. After cooling to 30° C., 14.5 g of ethoxycarbonylformamide oxime are added and the mixture is stirred at 45° C. for 3 h. The precipitated solid is filtered off with suction and the filtrate is concentrated to 50 ml and, together with the solid, added to 250 ml of ice-water. The solid is filtered off with suction and dried at 50° C. under reduced pressure. This gives 28.7 g of the product as a white solid of mp. 172-174° C.
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