With the purpose of search of new biologically active substances the synthesis of nine derivatives of 5-nitro-9-Narylaminoacridinium (2a-i) has been carried out by interaction of the corresponding 5-nitro-9-chloracridines and aromatic amines in two ways: in the phenol medium (method A) and in the dioxane medium in the presence of hydrochloric acid (method B). It has been experimentally proven that method B is more expedient because it is characterized by the absence of toxic phenol in the synthesis, reduction of the experiment time, a high yield of the desired product (87-94%). The structure and individuality of compounds synthesized that are undescribed in the literature have been confirmed by IR-, NMR-spectral and chromatographic analysis. The choice of the pharmacological screening spectrum has been conducted using data of PASS-prognosis, scientific and patent literature. It has been found experimentally that the substances synthesized possess a moderate bacteriostatic and fungistatic, expressed anti-inflammatory and analgesic, high diuretic (compounds 2d-f) and antidiuretic (compounds 2h-i) activities. According to the classification by K.K.Sydorov the compounds synthesized when introduced intragastrically belong to low toxic compounds. Some regularities of the “structure – biological activity – toxicity” dependence have been analyzed, and it is an important element in determining the areas for further research to develop new biologically active substances.