Efficient synthesis and biological evaluation of 4-arylcoumarin derivatives

Two bioactive natural 4-arylcoumarins, 5,7,4'-trimethoxy-4-phenylcoumarin (1a), 5,7-dimethoxy-4-phenylcoumarin (1b) and five closely related derivatives 1c-g were synthesized. In vitro evaluation with a catechol subunit for antioxidant and antimicrobial activity, these compounds using standard methods showed that compounds 1d, 1f displayed promise radical scavenging activity and 1f was found to be the most active one against Bacillus dysenteriae.