Discovery of β-carboline-(phenylsulfonyl)furoxan hybrids as potential anti-breast cancer agents.

The cytotoxicity properties of the β-carboline alkaloids have been broadly investigated. However, the potential application of β-carbolines was hindered due to the moderate activity in cancer. In the present study, thirty β-carboline-(phenylsulfonyl)furoxan hybrids (11a-j, 12a-j and 13a-j) were designed and synthesized through esterification and amidation reaction strategy, and their inhibitory activities against the human breast cancer cell lines MCF-7 and MDA-MB-231 were evaluated by CCK-8 assay. Biological evaluation presented that the most promising amide derivative 13h, substituted with p-methoxyphenyl group at position 1, generated high concentration of NO and evidently depressed the MCF-7 (IC = 0.89 μM) and MDA-MB-231 (IC = 0.62 μM) cells proliferation. Particularly, the wound healing and transwell assays demonstrated that 13h significantly inhibited the migration and invasion of MDA-MB-231cells. Furthermore, the preliminary mechanisms studies indicated that 13h induced G2/M phase arrest and apoptosis possibly causing by ROS accumulation and ROS-mediated DNA damage. Based on these considerations, 13h may be a promising antimetastatic agent for breast cancer, which is noteworthy for further exploration.