Synthesis and cytotoxic activities of 1-benzylidine substituted β-carboline derivatives

A series of new β-carboline derivatives, bearing a benzylidine substituent at position-1, has been prepared and evaluated in vitro against a panel of human cell lines. The N2-benzylated β-carbolinium bromates represented the most interesting cytotoxic activities. In particular, compounds 19 were found to be the most potent compounds with IC50 values lower than 5 μM against 10 strains human tumor cell lines. These results confirmed that the N2-benzyl substituent on the β-carboline ring played an important role in the modulation of the cytotoxic activities and suggested that further development of such compounds may be interest.