Synthesis and Evaluation of Rosin-Based Triazole Derivatives as Novel Herbicides

To develop novel herbicides derived from natural product sources, a range of acrylopimaric acid triazole derivatives was synthesized with rosin as the starting compound. The herbicidal effectiveness of these derivatives was assessed and tested against <i>Cyperus rotundus</i>, <i>Cirsium arvense</i>, <i>Portulaca oleracea</i>, <i>Lolium perenne</i>, and <i>Echinochloa crus-galli</i> both pre-emergence and postemergence. Compounds <b>4a</b>, <b>4g</b>, <b>4m</b>, and <b>4p</b> exhibited inhibitory activity against <i>C. rotundus</i>, with compound <b>4m</b> demonstrating the most effective herbicidal activity. Its pre-emergence IC₅₀ was lower than the positive control glyphosate (6.658 mg L^-1 compared to 7.556 mg L^-1, respectively), and postemergence treatment resulted in a higher degree of seedling bleaching compared to the positive control treatment. Enzyme activity inhibition studies revealed that compound <b>4m</b> exhibits significant inhibition against transketolase (TK), with molecular docking analysis suggesting that compound <b>4m</b> can interact with TK. Furthermore, the analysis of 3D-QSAR revealed that the molecular configuration and electrostatic distribution are crucial factors for enhancing the biological activity of compounds. In conclusion, these discoveries suggest the potential of compound <b>4m</b> as an herbicide and provide insights for the control of <i>C. rotundus</i>.