Synthesis and antitumor activity of new thiosemicarbazones of 2-acetylimidazo[4,5- b ]pyridine

A number of thiosemicarbazones of 2-acetyl-imidazo[4,5-b]pyridine were prepared in order to investigate their in vitro antineoplastic activities. Three compounds: (i) 2-acetylimidazo[4,5-b]pyridin-4-sec-butyl-3-thiosemicarbazone [(A7), NSC674098], (ii) 2-acetylimidazo[4,5-b]pyridin-4-tert-butyl-3-thiosemi-carbazone [(A9), NSC674099], (iii) 2-acetylimidazo[4,5-b]pyridin-4-cyclohexyl-3-thiosemicarbozone [(A11), NSC674101] showed remarkable activity against some of the cell lines tested. The Biological Evaluation Committee of N.C.I. determined that further secondary testing should be carried out (these compounds were tested against prostate cancer).