Design, synthesis, antifungal, and antibacterial evaluation of ferulic acid derivatives bearing amide moiety.

Natural compounds' derivatives as lead structures could effectively solve plant disease problems. In this article, amide compounds and amide ester compounds were synthetized through ferulic acid as the parent nucleus structure, and their biological activities in vitro and in vivo were evaluated. Compound 1q was screened out as the one with the best activity performance toward Xanthomonas axonopodis pv. citri (Xac), which displayed the inhibition rate of 100% and the EC50 as low as 4.56 μg/mL. The results of in vivo experiments on citrus leaves infected with Xac showed that compound 1q had a protective efficacy of 60.98% and a curative efficacy of 26.56%. The mechanism of action as well as molecular docking was previously studied using extracellular polysaccharide (EPS) content, bacterial membrane permeability, and scanning electron microscopy (SEM) observations. Experimental results show that compound 1q can become an antibacterial agent for preventing and managing plant diseases.