The intermediate 6-methyldiphenylamine-2,2'-dicarboxylic acid (V) has been synthesized in two similar ways. 1. By Jourdan-Ullman copper-catalyzed condensation of 6-methylbenzoic acid (I) with 2-aminobenzoic acid (II); and 2. By the same type of condensation, but using 2-amino-3-methylbenzoic acid (III) and 2-chlorobenzoic acid (IV). The cyclization of the intermediate dicarboxylic acid (V) under acidic conditions gives 5-methyl-9-oxo-9,10-dihydroacridine-4-carboxylic acid (VI), which is treated with hot SOCl2 and DMF to yield 9-choloro-5-methylacridine-4-carbonyl chloride (VII). The reaction of (VII) with N,N-dimethylethylenediamine (VIII) in dichloromethane affords the corresponding amide (IX), which is finally treated first with phenol at 100 C and then with a stream of dry ammonia at 110-20 C to obtain the target 9-aminoacridine derivative.