N-Aryl-substituted 2-nitrosoanilines (=2-nitrosobenzenamines) 1, readily available by nucleophilic substitution of the ortho-H-atom in nitroarenes with arenamines, react with 2-substituted acetic acid esters in the presence of a weak base giving 1-arylquinoxalin-2(1H)-ones (Scheme2). This cyclocondensation allows for the synthesis of compounds 24, unsubstituted at C(3) or substituted by alkyl, aryl, ester, amide, and keto groups, in good to excellent yields (Tables14).