New 5-substituted thiazolo[3,2-b][1,2,4]triazol-6-ones: synthesis and anticancer evaluation.

Following [2+3]-cyclocondensation reaction of 1,2,4-triazole-3(5)-thiol with N-arylmaleimides or with monochloroacetic acid and oxocompounds, N-(R-phenyl)-(6-oxo-5,6-dihydro[1,3]thiazol[3,2-b][1,2,4]triazol-5-yl)acetamides (1-5) and 5-ylidene-[1,3]thiazolo[3,2-b][1,2,4]triazol-6-ones (6-11) were synthesized as possible anticancer agents. Anticancer activity evaluation on the full panel of nearly 60 human cancer cell lines showed that synthesized compounds displayed this kind of activity on renal cancer, leukemia, colon cancer, breast cancer and melanoma cell lines. It was shown that 5-ylidene-[1,3]thiazolo[3,2-b][1,2,4]triazol-6-ones are characterized with more potent anticancer activity than respective amides. The structures of the compounds were determined by (1)H NMR, (13)C NMR and X-ray analysis.