Abstract Base-catalyzed intramolecular nucleophilic substitution for the 2-nitro group in 2- hydroxyanilides of 2-nitrobenzoic acids gave dibenzo [b, f][1, 4] oxazepin-11 (10 H)-ones. In particular, 3-nitrodibenzo [b, f][1, 4] oxazepin-11 (10 H)-one was obtained from N-(2- hydroxyphenyl)-2, 4-dinitrobenzamide. The nitro group in the product could also be replaced under the action of O-and S-nucleophiles.