鉴于稻田中恶性杂草千金子（Leptochloa chinensis (L.) Nees）的流行，针对该杂草的新型除草剂的开发引起了广泛的兴趣。在此，我们报道了一种新型二苯醚-嘧啶杂化物 DEP-5，作为一种系统性芽前/芽后除草剂候选物，用于稻田广谱杂草控制，特别是针对中华乳草。值得注意的是，即使在温室条件下，DEP-5 的剂量为 37.5 g a.i./ha，也能对抗性生物型表现出超过 80% 的除草活性，并且在稻田中，剂量为 150 g a.i./ha 时，可以完全控制 L. chinensis。我们发现 DEP-5 作为乙酰羟酸合酶 (AHAS) 的非竞争性抑制剂，抑制常数 (Ki) 为 39.4 μM。我们提出 DEP-5 以两种疏水驱动的结合模式与 AHAS 结合，这与商业 AHAS 抑制剂不同。总体而言，这些研究结果表明，DEP-5 具有开发成为控制羊草的除草剂的巨大潜力，并激发了新型 AHAS 抑制除草剂设计的新概念。

Given the prevalence of the malignant weed Chinese Sprangletop (Leptochloa chinensis (L.) Nees) in rice fields, the development of novel herbicides against this weed has aroused wide interest. Here, we report a novel diphenyl ether-pyrimidine hybrid, DEP-5, serving as a systematic pre/postemergence herbicide candidate for broad-spectrum weed control in rice fields, specifically for L. chinensis. Notably, DEP-5 exhibits over 80% herbicidal activity against the resistant biotypes even at 37.5 g a.i./ha under greenhouse conditions and has complete control of L. chinensis at 150 g a.i./ha in the rice fields. We uncover that DEP-5 acts as a noncompetitive inhibitor of acetohydroxyacid synthase (AHAS) with an inhibition constant (Ki) of 39.4 μM. We propose that DEP-5 binds to AHAS in two hydrophobic-driven binding modes that differ from commercial AHAS inhibitors. Overall, these findings demonstrate that DEP-5 has great potential to be developed into a herbicide for L. chinensis control and inspire fresh concepts for novel AHAS-inhibiting herbicide design.