Reaction of 1-Nitro-9,10-anthraquinone-2-carboxylic Acid with 2-Aminoethanol

1-Nitro-9,10-anthraquinone-2-carboxylic acid reacts with 2-aminoethanol to give 1-(2-hydroxy- ethylamino)-9,10-anthraquinone-2-carboxylic acid which undergoes intramolecular cyclization to 1,2,3,5,8,13- hexahydroanthra[1,2-e][1,4]oxazepine-5,8,13-trione on heating in acetic acid. Reactions of the cyclization product with amines result in cleavage of the seven-membered heteroring.