FURTHER STUDIES OF AMINOBENZACRIDINES¹

Abstract

In previous publications (1,2) from this laboratory the preparation of a series of substituted aminobenzacridines was described. The present paper describes further members of this series of compounds ¡with special emphasis on those in which the amine group is peri rather than para to the hetero nitrogen atom. The number of possible isomers is five.Of these I and III were made in satisfactory yields, partial syntheses of IV and V were achieved, and II was not studied, before termination of the study of this series became necessary.2-Bromo-3-nitrobenzoic acid condensed readily with 1or 2-naphthylamine to give a 2-naphthylamino-3-nitrobenzoic acid which was readily cyclized with phosphorus oxychloride. The acridones so obtained were reduced by stannous chloride to the corresponding aminobenzacridones and by aluminum amalgam to the desired aminoacridines (I and III). Proof of the structure of the products was obtained by diazotization of the aminobenzacridones and conversion of them to triazolobenzacridones.Compound IV was approached by condensing 3-amino-2-naphthoic acid with o-nitrobromobenzene and cyclizing the product with phosphorus oxychloride. The yields in this latter step were poor. The original condensation product also was reduced to 3-(o-aminophenylamino)-2-naphthoic acid. This gave a cyclic amide on heating, and the desired aminobenzacridone was not obtained.Compound V was approached by coupling 3-phenylamino-2-naphthoic acid 1 From the Ph.D. thesis of F.