A novel organobismuth compound, 1-[(2-di-p-tolylbismuthanophenyl)diazenyl]pyrrolidine, induces apoptosis in the human acute promyelocytic leukemia cell line NB4 via reactive oxygen species.

A novel organobismuth compound, 1-[(2-di-p-tolylbismuthanophenyl)diazenyl]pyrrolidine (4), which has 1-(phenyldiazenyl)pyrrolidine (1) substituent in a benzene ring of tri(p-tolyl)bismuthane (2), was synthesized and tested for biological activity toward human tumor cell lines. 4 had a potent anti-proliferative effect on human cancer cell lines, although both 1 and 2 exhibited only weak activity. The sensitivity of leukemic cell lines to 4 was relatively high; IC(50) values for the human leukemia cell line NB4 and cervical cancer cell line HeLa were 0.