Antitumor properties of selected 1,2,4-triazine derivatives.

Several new 3-thio-1,2,4-triazine derivatives were synthesized and investigated for antimicrobial and antitumor activity in in vitro and in vivo systems. Some of the investigated compounds inhibited growth of gram-positive bacteria and fungi at the concentration of 5-20 microgram/ml. Two methyl-nitro-imidazole-triazine derivatives (XI and XIII) inhibited the development of chicken fibroblast at 0.1 microgram/ml. Three out of fourteen compounds tested (V, XII and XIII) inhibited by 75% growth of sarcoma 180 when injected s.c. for 14 consecutive days in the doses of 50 and 100 mg/kg. At the same doses no effect was noted on leukemia L 1210 and P 388. Correlation between chemical structure, cytotoxic activity, antitumor effect and antimicrobial activity is discussed.