Synthesis and study of benzofuran-pyran analogs as BMP-2 targeted osteogenic agents.

Twenty-four novel benzofuran-pyran derivatives were synthesized and evaluated for their anti-osteoporotic activity in primary cultures of rat calvarial osteoblasts in vitro. Among all the compounds screened for the alkaline phosphatase activity, three compounds 4e, 4j and 4k showed potent activity at picomolar concentrations in osteoblast differentiating stimulation. Additionally, these compounds were found effective in mineralization, assessed by alizarin red-S staining assay. Compounds were again validated through a series of other in vitro experiments. Moreover, molecular dynamics simulations demonstrated that both benzofuran and pyran moieties are requisite to fit into the active site of BMP-2 receptor, a key target of the osteogenic agents. The obtained results strongly convey that compound 4e is a potential bone anabolic agent among synthesized series, which can be further explored as a drug lead for treating osteoporosis.