[en] Earlier the authors synthesized new derivatives of tetrazole, the study of which as biologically active compounds revealed substances exhibiting varied biological effects, including radioprotective activity. The protection of lethally irradiated animals at doses LD_95-99/30 reached 70%, and the toxicity LD₅₀ was 320-2500 mg/kg. In the present study work, the authors continue their work on the search for new radioprotectors among tetrazole derivatives, focusing on 1(2)-aminoalkyl-5-substituted aryltetrazoles I-XXVII. As a result of alkylation of tetrazoles with haloalkylamines, chiefly N₂-isomers were isolated. The toxicity and radioprotective properties of the substances were evaluated for the N₂-isomers and their salts. 9 refs., 4 tabs