Novel dibenzo[b,d]furan-1H-1,2,4-triazole derivatives: Synthesis and antitumor activity.

Twenty-four new dibenzo[b,d] furan-1H-1,2,4-triazole derivatives were synthesized and investigated for in vitro cytotoxic activity against five tumor cell lines. The results show that the substitution at 4-position of the 1,2,4-triazole with a benzyl, 4-bromophenacyl or naphthylacyl group could be crucial for prommoting cytotoxic activity. Especially, compound 28 was found to be the most powerful derivative with IC50 values lower than 3.50 mu M against five investigated tumor cell lines, while compound 19 showed selective activity against leukemia (HL-60) and breast carcinoma (MCF-7) cell lines with IC50 values of 0.80 and 1.76 mu M, respectively. Compound 19 can induce cell cycle arrest at G2/M phase and apoptosis in SMMC-7721 cells.