Synthesis of chlorinated tetronamides and their ability to inhibit bacterial biofilm formation by Xanthomonas campestris pv. campestris

Abstract

The class of natural and synthetic furan-2(5H)-ones has attracted attention due to its diverse bioactivities, such as anticancer, insecticidal, and anti-inflammatory properties, as well as its ability to inhibit bacterial biofilm formation. Xanthomonas campestris pv. campestris, the causative agent of black rot disease, causes significant financial losses due to reduced productivity and quality of Brassica spp. crops. Biofilm formation by X. campestris is crucial for its ability to infect plants. Thus, the tetronamides with a 3-chloro-furan-2(5H)-one scaffold were synthesized (47–73% yield) using mucochloric acid as the starting material, and their antibiofilm potential was evaluated. The compounds were characterized by IR, mass spectrometry (MS), ¹H NMR, and ¹³C NMR. The minimum inhibitory concentration (MIC) for the six compounds was determined using the microdilution method. The compounds exhibited MIC values of 1500 µg mL⁻¹, except for compound 3, which had a MIC of 1000 µg mL⁻¹. The ability of these compounds to inhibit biofilm formation by X. campestris was measured at subinhibitory concentrations, and the IC₅₀ values for the six compounds tested ranged from 27.6 to 60.9 µg mL⁻¹. These findings provide a basis for developing sustainable strategies to combat black rot, a biofilm-related disease caused by Xanthomonas campestris pv. campestris.

Graphical abstract