Discovery of pyrazolone spirocyclohexadienone derivatives with potent antitumor activity.

Starting from easy accessible pyrazoletetrahydropyran acetals, a series of new pyrazolone spirocyclohexadienone derivatives were synthesized and assayed for antitumor activity. Compound 10s was identified to possess good antitumor activity. It could induce MDA-MB-231 cancer cell apoptosis in a concentration dependent manner and arrest the cell cycle progression mainly at the G1 phase.