SYNTHESIS OF IMIDAZO[2,1-b][1,3,4]THIADIAZOLE DERIVATIVES AS POSSIBLE BIOLOGICALLY ACTIVE AGENTS.

A series of 2-(4-methylbenzyl)-5,6-substituted-imidazo[2,1-b][1,3,4]thiadiazole derivatives were synthesized, characterized and evaluated for antiproliferative activity and cancer chemopreventive activity. Results showed that molecules with formyl and thiocyanate substiments at the 5 position exhibited an increase in activity against the full panel of 60 human tumor cell lines at a minimum of five concentrations at 10-fold dilutions. Derivative 22 displayed significant in vino anticancer activity against colon cancer (MID GI₅₀ = 0.75 μM). The cancer chemopreventive effect of 19 (IC₅₀ = 489 nM) was almost equipotent to standard oleanolic acid (IC₅₀ = 449 nM).