Based on the structure of lead compound N-(m-fluoro-benzyl)-6-amino-coumarin, a series of novel N-acyl-N-(m-fluoro-benzyl)-6-amino-coumarins were designed and synthesized through the principle of bioactive substructure combination. Their structures were characterized by 1 H NMR, ESI-MS and elemental analysis. N-trifluoroacetyl substituted compound d5 was further confirmed by X-ray single crystal diffraction. The herbicidal activities of synthesized compounds were evaluated as well. The results indicated that compounds substituted respectively by N-chloracetyl, N-bromoacetyl, N-trifluoroacetyl and N-(2,4-dichlorophenoxyacetyl) compounds d2, d3, d5 and d17 exhibited marked inhibition against the roots and stems of Amaranthus retroflexus with inhibitory rates above 75% at 100 mg/L, more active than acetochlor EC. In post-emergence treatment experiment, compounds d3 and d17 substituted respectively by N-bromoacetyl and N-(2,4-dichlorophenoxyacetyl) showed more than 76% inhibition against A. retroflexus and other dicotyledons at 1500 g/ha in greenhouse. Compound d17 is safe to monocotyledonous crops wheat, corn and rice at 1500 g a.i./hm 2 .
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.