(a) 1,2,4-Trihydroxyanthracene-9,10-dione in the presence of boric acid condensation of aniline, sulfonation, into sodium salt, and then will product nitrifying; (b) 2-Bromo-1,4-dihydroxyanthracene-9,10-dione or 2-Chloro-1,4-dihydroxyanthracene-9,10-dione and aniline condensation, sulfonation, then will product nitration.
