5-Acetamidoanthranilic acid (0.64g) and 2,6-difluorobenzoyl chloride (1.3 g) were reacted in triethyl amine/toluene (1/1) (20 mL) like described for compound (9), reaction time 1 h. Ethyl acetate (50 mL) and HCl-solution (1 mL 4N in 50 mL water) were added resulting in the formation of a precipitate.The mixture was filtered and the residue dissolved in THF followed by evaporation to dryness, subsequent dissolution in hot dioxane followed by precipitation with hexane resulted in colourless crystals of 6-acetamido-(2,6-difluoro-phenyl)-benzo[d][1,3]oxazin-4-one (0.98 g), mp.246 C, MS m/e.: 316 M+.
