Abstract:
Plant parasitic nematodes may cause severe damages to crops globally. In this study, fifteen novel 4,5,5-trifluoropent-4-enamide derivatives were designed and synthesized, and their nematicidal activities both
in vitro and
in vivo (in sand) were determined. Compounds with high activity in sand were further investigated for their
in vivo activities in matrix. Results of the
in vitro test showed that some of compounds exhibited better nematicidal activity. Among the synthesized molecules, compounds
B8 containing a furan ring exhibited excellent nematicidal activity against
Meloidogyne incognita and
Bursaphelenchus xylophilus, with LC
50/72 h values of 1.22 mg/L and 0.53 mg/L, respectively. Furthermore, most of the compounds showed 100% inhibition rate against
M. incognita at 40 mg/L in sand in the
in vivo test. Among which compound
B10 containing a benzothiazole ring showed the best nematicidal activity. It exhibited 66.0% inhibition rate at 2.5 mg/L. Results of the
in vivo test in matrix showed that compound
B6 containing a thiophene ring was the most active compound. It showed 31.0% inhibition rate at 5 mg/L. Preliminary analysis on structure-activity relationship showed that the compounds containing non-substituted five-membered ring such as thiophene, furan and thiazole demonstrated better bioactivity than those compounds containing bulky six-membered ring or fused ring in the molecule.