Synthesis and antimicrobial assessment of novel coumarins featuring 1,2,4-oxadiazole

Oxadiazoles are heterocyclic compounds with a variety of application in many pharmaceuticals and agrochemical products. We report herein the convenient synthesis of 4-[(3-aryl-1,2,4-oxadiazol-5-yl)methoxy]-coumarins ( 4a – f ), 6-[(3-aryl-1,2,4-oxadiazol-5-yl)methoxy]-4-methylcoumarins ( 7a – f ) and 7-[(3-aryl-1,2,4-oxadiazol-5-yl)methoxy]-4-phenylcoumarins ( 10a – f ) in high yields by one-pot condensation reaction of esters with amidoximes. The structures of the synthesized compounds were established on the basis of IR, NMR and mass spectrometry. The antibacterial and antifungal activities of synthesized compounds were evaluated. Graphical Abstract