A series of 4-hydroxyaurone derivatives 4a-4v were synthesized and characterized by 1H NMR, 13C NMR, and elemental analysis. Their herbicidal activities against four species of plants were evaluated in a greenhouse by both pre- and post-emergence treatments at a dosage of 750 g a.i. ha-1. The bioassay revealed that 4-hydroxyaurones exhibited moderate to good herbicidal activities against dicotyledons plants for post-emergence treatment. For instance, (Z)-4-hydroxy-2-(4-nitrobenzylidene)benzofuran-3(2H)-one (4m), demonstrated 74.5% inhibitory activity against Amaranthus retroflexus L., higher than that of the positive control herbicide acetochlor. Thus, compound 4m may serve as a new possible leading compound for the discovery of post-emergence herbicide.

中文翻译：

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4-羟基金龙酮的合成及其除草活性

合成了一系列的4-羟基金龙酮衍生物4a - 4v ，并通过1 H NMR，13 C NMR和元素分析对其进行了表征。在温室中，通过芽前和芽后以750 g ai ha -1的剂量处理，评估了它们对四种植物的除草活性。生物测定显示4-羟基金酮对出芽后处理的双子叶植物表现出中等至良好的除草活性。例如，（Z ）-4-羟基-2-（4-硝基亚苄基）苯并呋喃-3（2 H ）-one（4m ）表现出对A菜的74.5％抑制活性L.，高于阳性对照除草剂乙草胺。因此，化合物4m可以作为发芽后除草剂发现的一种新的可能的主导化合物。