Discovery of novel 3‐{[(5,5‐dimethyl‐4,5‐dihydroisoxazol‐3‐yl)sulfonyl]methyl}benzo[d]isoxazole analogs as promising very long chain fatty acids inhibitors

Abstract

Very long chain fatty acids (VLCFAs) are one of the most principal and promising targets for herbicides discovery. In order to explore and find novel VLCFAs inhibitors with higher herbicidal activity and improved crop safety, a variety of new 3‐{[(5,5‐dimethyl‐4,5‐dihydroisoxazol‐3‐yl)sulfonyl]methyl}benzo[d]isoxazole derivatives were reasonably designed and synthesized. The results of greenhouse experiments indicated that several compounds exhibited good herbicidal activity against Digitaria sanguinalis, Echinochloa crus‐galli, and Setaria faberii at rates of 150 g ai/ha. Compounds g4 and h1 displayed promising herbicidal activity against D sanguinalis and E crus‐galli at rates of 75 g ai/ha, which is better than commercial pyroxasulfone and S‐metolachlor. Moreover, compound h1 displayed higher activity against E crus‐galli, D sanguinalis, and S faberii than pyroxasulfone and S‐metolachlor even at a rate of 37.5 and 18.75 g ai/ha. Furthermore, both of the compounds g4 and h1 were much safer to these tested crops, especially to rice, wheat and rape, at the rate of 150 g ai/ha than pyroxasulfone. Therefore, h1 may act as a new lead structure for novel herbicides discovery.

Very long chain fatty acid–inhibiting herbicides: Current uses, site of action, herbicide-resistant weeds, and future

“…Researchers at the Chinese Academy of Agricultural Sciences reported a series of potent N -trifluoroethylpyrazole-substituted isoxazolines that had encouraging weed control activity along with corn selectivity in the greenhouse and field studies at rates lower than that of metolachlor (Ma et al 2010) (Figure 12B). Researchers at Dongguan HEC Pesticides R&D Company in China published a family of benzisoxazole-substituted isoxazolines (Figure 12C) that was competitive with pyroxasulfone to control some weed species, with improved crop safety in rapeseed, rice, and wheat crops (Lin et al 2021). Substantial research efforts have been extended in search of bioisosteres of isoxazolines.…”