Synthesis of novel 3/5(3,5)-(di)nitropaeonol hydrazone derivatives as nematicidal agents

Abstract

Eighteen novel 3/5(3,5)-(di)nitropaeonol hydrazone derivatives were prepared, and their structures well characterized by ¹H NMR, HRMS, and mp. Due to the steric hindrance, the substituents on the C = N double bond of all hydrazine compounds (except E/Z = 4/1 for IV-1g, IV-1l, IV-2b, and E/Z = 3/2 for IV-1n, IV-3a) adopted E configuration. Among all compounds, four compounds 2, 4, IV-1j, and IV-1n exhibited potent nematicidal activity than their precursor paeonol, especially 5-nitropaeonol (2) and 3,5-dinitropaeonol (4) displayed the most potent nematicidal activity Heterodera glycines in vivo with LC₅₀ values of 32.3307 and 36.7074 mg/L, respectively.

Keywords: Paeonol; botanical nematicides; hydrazine; nematicidal activity; structural modification.