7-Fluoro-1H-benzo[d][1,3]oxazine-2,4-dione (CAS No.321-50-6), its synonyms are 2H-3,1-Benzoxazine-2,4(1H)-dione, 7-fluoro- ; 7-Fluoro-2H-3,1-benzoxazine-2,4(1H)-dione ; 4-Fluoroisatoic anhydride .