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 Cyperus rotundus, Cirsium arvense, Portulaca oleracea, Lolium perenne, and Echinochloa crus-galli both pre-emergence and postemergence. Compounds 4a, 4g, 4m, and 4p exhibited inhibitory activity against C. rotundus, with compound 4m 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 4m exhibits significant inhibition against transketolase (TK), with molecular docking analysis suggesting that compound 4m 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 4m as an herbicide and provide insights for the control of C. rotundus.