A series of novel diaryl ureas containing 4-[(2-amino-6-trifluromethyl) pyrimidine-4-yl] piperazine-1-yl group were synthesized and evaluated for their cytotoxic activities in a panel of human cancer cell lines. Compared with the reference drug Sorafenib, some compounds showed more potent and a broader spectrum of anti-cancer activities. Among them, compound 2p demonstrated significant inhibitory activities against MDA-MB-231, HT-29 ...