Discovery of novel (3E)-4, 8-dimethyl-1, 3, 7-nontriene skeleton analogues as potential herbicide candidates

Natural products and their synthetic derivatives are notable sources for discovering new lead compounds of herbicides. Terpene natural product (3E)-4, 8-dimethyl-1, 3, 7-nontriene (DMNT) has been proven to be able to repel and kill the insects, whereas its other bioactivities have rarely been studied.

In this study, we focus on the herbicidal activity of DMNT and its derivatives. A series of oxygen- or nitrogen-containing DMNT allyl derivatives were designed and synthesized as novel herbicide candidates. They were characterized by ¹H NMR, ¹³C NMR and HRMS spectral analysis. Compared to DMNT, the herbicidal activities of its derivatives were generally enhanced against monocotyledonous (Echinochloa crus-galli, Lolium perenne L.) and dicotyledonous weeds (Portulaca oleracea L., Abutilon theophrasti Medicus). Particularly, the DMNT hydroxylation product (DMNT-OH, 2) completely inhibited the germination of E. crus-galli at 300 mg/L in the Petri dish assay, and also showed good herbicidal activity against the growth of weeds in the greenhouse test. Furthermore, it exhibited excellent crop safety for peanuts, wheat, rice and maize even at a dosage up to 2000 g/hm². Ultimately, to further demonstrate the structural specificity and superior activity of DMNT-OH, its herbicidal activity was comparatively analyzed with geraniol and geranial.

These findings suggested that the herbicidal activity of DMNT significantly enhanced after structural modification, and DMNT-OH has great potential as environmentally-friendly herbicide candidate for further development. This study lays the basis for the exploration of DMNT as a botanical herbicide. © 2026 Society of Chemical Industry.