Antioxidant and antibacterial evaluation of synthetic furomollugin and its diverse analogs

Diverse furomollugin (3) and its analogs (11-22) were synthesized in high yields via ceric ammonium nitrate-catalyzed formal [3 + 2] cycloaddition as a key step. The in vitro antioxidant activities of synthesized compounds were determined by analyzing radical scavenging activities for 1,1-diphenyl-2-picrylhydrazyl (DPPH), nitric oxide, and hydrogen peroxide assays. The results showed that the synthesized furomollugin analogs had effective antioxidant power. Dihydronaphthofurans with 2-alkyoxy or 2-aryl group were the most potent radical scavengers in DPPH assay. Moreover, the antibacterial activities of those compounds were also evaluated and the highly active compounds were selected for further determination of minimal inhibitory concentrations (MICs). Compound 19 (MIC = 2 mu g/mL) was found to be highly active against the gram-negative bacteria Escherichia coli (KCTC-1924) than the Ampicillin standard (MIC = 4 mu g/mL). Compound 22 (MIC = 0.5 mu g/mL) inhibited gram-positive bacteria Staphylococcus aureus (KCTC-1916) growth as effectively as ampicillin (MIC = 0.5 mu g/mL).