Antibacterial agent 206 (Compound 10e) is a indolylacryloyl-derived oxacins, which exhibits broad antibacterial spectrum with MIC of 0.25-1 μg/mL. Antibacterial agent 206 reduces the exopolysaccharide, eliminates the biofilm, and thus attenuates the drug resistance. Antibacterial agent 206 exhibits antibacterial activity through destory of membrane integrity, accumulation of reactive oxygen species ROS, and inhibition of DNA replication^[1].