Discovery of 4-nitro-3-phenylisoxazole derivatives as potent antibacterial agents derived from the studies of [3+2] cycloaddition

Polysubstituted phenylisoxazoles were designed and synthesized to discover new antibacterial agents via [3 + 2] cycloaddition. Thirty-five compounds with a phenylisoxazole scaffold were characterized by NMR, HRMS, and X-ray techniques. After being evaluated against Xanthomonas oryzae (Xoo), Pseudomonas syringae (Psa), and Xanthomonas axonopodis (Xac), 4-nitro-3-phenylisoxazole derivatives were found to better antibacterial activities. Further studies have shown that the EC50 values of these compounds were much better than that of the positive control, bismerthiazol.

Automated summary

Polysubstituted phenylisoxazoles were synthesized and found to exhibit improved antibacterial activities, especially the 4-nitro-3-phenylisoxazole derivatives. The compounds showed better inhibitory effects against Xoo, Psa, and Xac compared to the positive control bismerthiazol.