Green synthesis, characterization, structure, biological activity, theoretical calculations and drug-likeness analysis of coumarins

Condensation of salicylaldehydes and 2-hydroxynaphthaldehyde with various β−dicarbonyl derivatives 2a-c, in the presence of KF-Al2O3, leads to the synthesis of a series of coumarins 3-8 and benzo[f]coumarins 10 respectively by a solvent free reaction under microwave irradiation. The catalyst is recovered by a simple filtration and reused in subsequent reactions. The structure of all synthesized compounds has been established by using analytical techniques such as IR, 1H and 13C NMR spectroscopic spectra and elemental analysis. Most of the coumarins exhibited significant antibacterial activity against S. aureus Gram-positive bacteria compared to Cefotaxime as positive control. The compounds 4a and 7a demonstrated moderate antimicrobial activity against compound 8a is extremely sensitive.. In addition, the compounds showed moderate to good antiradical (DPPH) activity. Theoretical calculations let us to confirm the reaction mechanism. Parameters drug-likeness and physicochemical properties including pharmacokinetic analysis of the synthesized compounds was performed using DruliTo program.publishe