Nematicidal Activities of Diamides with Diphenylacetylene Scaffold Against Meloidogyne Incognita

With the goal of searching for new potential nematicides with high activity and low toxicity, new molecules are needed as potential prototypes for the synthesis of new nematicidal compounds. A series of novel diamides based on diphenylacetylene scaffold were designed and synthesised. The conformation of the amide was restricted through the ten-membered H-bonded ring. Their structures were characterised by H-1 NMR, C-13 NMR, F-19 NMR, and high-resolution mass spectrometry. The preliminary bioassays evaluated against Meloidogyne Incognita indicated that most of the title compounds were endowed with moderate-to-good activities at the concentration of 25 mg L-1. In particular, compounds 9a, 9c, 9g, 9h, 9k, and 9l displayed >50% nematicidal activity at 5mg L-1. It is possible that the novel diamides with diphenylacetylene scaffold, which possess good nematicidal activities, provide distinct nematicidal chemotypes that can be used as leads for further optimisation.