Design, Synthesis, and Bioactivity Determination of Novel Malononitrile Derivatives Containing 1,2,3-Triazole

Using antifungal agrochemicals as the most economical solution might reduce plant diseases caused by pathogenic fungi, which have a significant negative impact on the quality and yield of food worldwide. In this work, 33 compounds (<b>G</b>) containing 1,2,3-triazole and malononitrile structures were synthesized. When the compounds were tested <i>in vitro</i> against six fungal species, they exhibited significant fungicidal activity toward <i>Botrytis cinerea</i> and <i>Rhizoctonia solani</i>. Compounds <b>G17</b> and <b>G30</b> displayed promising <i>in vivo</i> efficacy, with an EC₅₀ of 0.19 and 0.27 mg/L respectively against <i>R. solani</i>. Fungal ergosterol production was suppressed by compounds <b>G17</b> and <b>G30</b>, according to a preliminary analysis of their mechanism of action on <i>R. solani</i> using transcriptomics and scanning electron microscopy. It has been shown through experimentation that compounds <b>G17</b> and <b>G30</b> prevent <i>R. solani</i> from synthesizing ergosterol. Ultimately, it was anticipated that compounds <b>G17</b> and <b>G30</b> would be discovered to be low-toxic.