Synthesis and bio-activity evaluation of tetraphenyl(phenylamino) methylene bisphosphonates as antioxidant agents and as potent inhibitors of osteoclasts in vitro.

A new series of tetraphenyl bisphosphonates have been elegantly synthesized by one-pot method and were characterized by elemental analysis, FTIR, 1H, 13C, 31P NMR, mass spectra and evaluated for their in vitro antibone resorptive activity by inhibiting growth of osteoclasts. Two bisphosphonates 3g and 3f showed marked inhibition ratio (8 μM and 10 μM) and emerged as lead compounds. All compounds were tested for their antioxidant (DPPH scavenging, reducing power and inhibition of lipid peroxidation). They exhibited potent in vitro antioxidant activity dose-dependently.