New tetrazole-containing derivatives of 2,4-diamino-1,3,5-triazine were synthesized. The cytotoxic activity of the obtained compounds against Huh-7 and HeLa tumor cell lines was studied by the MTT test. The most significant antitumor activity was shown by 1,3,5-triazines containing a 5-phenyltetrazol-2-ylacetohydrazide fragment. The resulting compounds showed practically no cytotoxic effect on non-tumor cells of the human embryonic kidney line HEK293.

New tetrazole-containing derivatives of morpholin-4-yl-1,3,5-triazine and 4-methylpiperidin-1-yl-1,3,5-triazine were synthesized. The cytotoxic activity of the obtained compounds against human liver Huh-7 and human lung A549 tumor cell lines was tested by MTT assay. It was demonstrated that these substances do not show pronounced cytotoxic effects. The most significant antitumor activity was exhibited by 1,3,5-triazine containing a 5-phenyltetrazol-2-ylacetohydrazide moiety and a 4-methylpiperidine ring as substituents, as well as by 1,3,5-triazine bearing a 5-methyl-1H-tetrazol-1-ylacetohydrazide moiety and two morpholine rings. For these compounds, the interaction with DNA was studied by UV spectroscopy. Also, for N'-(4,6-dimorpholino-1,3,5-triazin-2-yl)-2-(5-methyl-1H-tetrazol-1-yl)acetohydrazide, the DNA binding constant was determined (K_bin 9.02×10⁴ M⁻¹), and the ability to inhibit the tyrosine kinase domain of the cell-surface receptors was evaluated. It was shown that the studied tetrazole-containing 1,3,5-triazine derivatives do not exhibit antioxidant activity against NO radicals and do not cause photoinduced hemolysis.