Synthesis and cytotoxic activity on islets of Langerhans of benzamide thiosemicarbazone derivatives

Eleven 1-(4-substituted α-arylaminobenzylidene)thiosemicarbazides 1 and the related semicarbazones 2 were synthesized and tested in vitro for their inhibitory effects on the islets of Langerhans. Only the thiosemicarbazones 1 suppressed the insulin and glucagon secretions while the somatostatin release persisted. The 1-(α-anilino-4-methylbenzylidene)thiosemicarbazide 1f was the most potent suppressor of insulin release adn lysed the islet β cells. Zinc sulfate protected islets from the suppressive and toxic effects of 1f . These compounds 1 could be potential drugs for the treatment of insulinomas.