High value-added application of natural forest product pinene: design, synthesis and 3D-QSAR study of novel campholenic aldehyde-based 4-methyl-1,2,4-triazole-thioether compounds with significant herbicidal activity.

For exploring novel natural product-derived herbicides, 16 novel campholenic aldehyde-based 4-methyl-1,2,4-triazole-thioether compounds were designed, synthesized, and characterized by FT-IR, H NMR, C NMR, ESI-MS and elemental analysis. The preliminary bioassay showed that, at 100 g/mL, most of the target compounds displayed significant inhibition activity against root-growth of rape( L.), with inhibition rates of 85.0%～98.2%(A-class activity level), much better than that of the positive control flumioxazin. In addition, an effective and reasonable 3D-QSAR model was established by CoMFA method in SYBYL-X 2.1.1 software. It was found that, the steric field was the major factor towards the herbicidal activity of the target compounds against L., and the introduction of bulky groups into and position of the benzene ring was favourable to increase the herbicidal activity. This kind of title compounds deserved further study as potential leading compounds for the discovery and development of novel herbicidal agents.