Discovery of novel aminophosphonate derivatives containing pyrazole moiety as potential selective COX-2 inhibitors

Cyclooxygenase is critical for maintaining physiological functions, whereas overexpression of COX-2 was closely implicated in various cancers. In this study, a series of novel aminophosphonate derivatives containing pyrazole moiety were synthesized with their anti-cancer activity evaluated. In vitro assays of the target compounds showed that Z21 displayed excellent COX-2 inhibitory activity against COX-2 (IC 50  = 0.22 ± 0.04 µM) and anti-proliferative activity against MCF-7 cell (IC 50  = 4.37 ± 0.49 µM). The apoptosis induction of compound Z21 was confirmed by flow cytometry and polymerase chain reaction. Further investigation demonstrated that compound Z21 induced apoptosis of MCF-7 cells through a mitochondrion-dependent pathway and involved cell-cycle arrest in G2 phase. Overall, these results provided some new insights into the design of therapeutic drugs for COX-2 inhibitors and indicated the connection between selective COX-2 inhibition and the anti-tumor activity.