PRELIMINARY INVESTIGATION OF THE LEWIS ACID-MEDIATED REACTIONS OF PHENOLS AND ETHYL PHENYLPROPIOLATE AS A SYNTHETIC ROUTE TO FLAVONOIDS AND ANTIMICROBIAL PROFILE OF THE RESULTANT 7-HYDROXY-4-PHENYL-2H-CHROMEN-2-ONE AND ANALOGS

Abstract

Synthetic chemists are increasingly exploring alternative routes to target products, considering factors like environmental threats, side product formation, cost, and efficiency. This is coupled with the health challenges that require urgent responses from new chemical entities. In this context, antimicrobial resistance has exacerbated global diseases, making them difficult to treat with prescribed drugs and causing a persistent public health crisis. These triggered our interest in the search for alternative antimicrobial agents, exploring different synthetic strategies for known bioactive natural compounds for further investigations. In this study, Lewis acid catalyst (FeCl3) and tetrahydrofuran as solvents in the one-pot synthesis of (neo)flavonoid derivatives from readily available phenols and ethyl phenylpropiolate were discovered to afford the coumarins in yields of 43–95%. The synthetic derivatives of 7-hydroxy-4-phenyl-2H-chromen-2-one and analogs obtained were biologically investigated for antimicrobial activity. The compounds showed moderate to poor antimicrobial activity. The effects of different substituents (-R) on the yield of the reaction are also discussed. Future studies should enhance the yield of derivative products and use different assay models for biological activity studies to fully explore the compounds` biorelevance.