Synthesis and fungicidal activity of methyl ( E )-1-(2-(( E )-2-methoxy-1-(methoxyimino)-2-oxoethyl)benzyl)-2-(1-arylidene)hydrazine-1-carboxylates †‡

To discover novel strobilurin fungicides, a series of methyl (E)-1-(2-((E)-2-methoxy-1-(methoxy-imino)-2-oxoethyl)benzyl)-2-(1-arylidene)hydrazine-1-carboxylates were designed based on the principle of biologically active splicing and the receptor target structure. The fungicidal activity results show that this class of compounds has excellent fungicidal activity, especially against S. sclerotiorum (Lib.) deBary , wheat white powder and puccinia polysora. The result of structure–activity relationship implied that the introduction of t-butyl in the side chain facilitates the hydrophobic interaction between the compound and the active site. The electrostatic effect of the substituents on the benzene ring is also a key factor affecting such activities. Among them, the compound I-1 not only showed a fungicidal effect comparable to that of kresoxim-methyl in vivo, but also had an excellent inhibitory effect on spore germination of P. oryzae Cav in vitro, which indicated that it could be used as a potential commercial fungicide for plant disease control. Graphic abstract