Synthesis of novel piperazine-based bis(thiazole)(1,3,4-thiadiazole) hybrids as anti-cancer agents through caspase-dependent apoptosis.

A series of novel piperazine-based bis(thiazoles) 13a-d were synthesized in moderate to good yields reaction of the bis(thiosemicarbazones) 7a, b with an assortment of -acetyl--aryl-hydrazonoyl chlorides 8a-f. Similar treatment of the bis(thiosemicarbazone) 7a, b with -aryl--phenylhydrazonoyl chlorides 10a, b afforded the expected bis(thiadiazole) based piperazine products 13b-d in reasonable yields. Cyclization of 7a, b with two equivalents of α-haloketones 14a-d led to the production of the corresponding bis(4-arylthiazol)piperazine derivatives 15a-h in good yields.