Sonochemical synthesis of polyarylated oxazoles as potential cytotoxic agents

The ultrasound assisted facile, rapid and one-pot synthesis of 2-aryl substituted 4,5-diphenyloxazoles was achieved via the reaction of commercially available benzoin (or 2-hydroxy-2-phenylacetophenone) with benzylamines in the presence of IBX under mild conditions. The methodology involved initial IBX mediated conversion of benzoin to benzil and then reaction with benzylamine followed by intramolecular cyclization (CO bond formation) and finally aromatization in the presence of air in the same pot. The methodology afforded a variety of desired products that were assessed for their cytotoxic properties against a number of cancerous and a non-cancerous cell lines. Compounds 3h, 3n and 3o showed promising growth inhibition of these cell lines except the non-cancerous one and interactions with SIRT1 in silico as well as in vitro.