Multicomponent Synthesis and Antimicrobial Activity of Dihydropyran-bis Coumarins

摘要

A synthetic route for the synthesis of biscoumarin fused with dihydropyran ring via one pot multicomponent reaction using hydroxy coumarins, formyl coumarins and malononitrile as precursors is proposed. A plausible mechanistic pathway for the formation of biscoumarin fused with dihydropyran ring is suggested. The synthesized compounds were characterized by FTIR, 1HNMR, 13CNMR and mass spectral data. Among the synthesized compounds, single crystals of 2-amino-5-oxo-4-(2- oxo-2H-chromen-6-yl)-4,5-dihydropyrano[3, 2-c]chromene-3-carbonitrile were obtained and their crystal parameters were discussed. Further, antimicrobial activities of all the synthesized compounds against microbial pathogens were investigated by broth micro dilution method. Majority of the compounds exhibited promising antimicrobial activities.