We herein report the synthesis, biological activity and preliminary structure-activity relationships of a series of diaryl[1,3]diazepines. These compounds were able to inhibit the proliferation of many cancer cell lines, such as HeLa, MCF-7, SGC7901 and A549. When HeLa cells were treated with lead compounds 7j and 7k at 3 [Formula: see text] concentration, cell arrest was observed in the G2/M phase.