Revisiting Al-2 quorum sensing inhibitors: direct comparison of alkyl-DPD analogues and a natural product fimbrolide

A revised synthesis of the fimbrolide as well as a direct comparison between the fimbrolide and alkyl-DPD analogues is presented. The studies have shown that alkyl-DPD analogues are more potent inhibitors of quorum sensing (QS) in Vibrio harveyi and Salmonella typhimurium, the two organisms with defined Al-2 QS systems.