Discovery of Enantiopure (S)-Methoprene Derivatives as Potent Biochemical Pesticide Candidates

(S)-Methoprene has been widely applied as a powerful biochemical pesticide to control disease vectors and other pestiferous arthropods of economic importance. As a juvenile hormone analogue, many products based on (S)-methoprene are developed and commercialized in the USA, Europe, and elsewhere. However, the agricultural use of (S)-methoprene and its analogues remains underexplored. Here, based on an intermediate derivatization strategy and structural modification, a series of enantiopure (S)-methoprene derivatives were designed for their expected bioactivity against two crop-threatening pests. Six compounds showed more than 2-fold stronger inhibition of emergence against Plutella xylostella than (S)-methoprene, among which one that was designated as B2 showed even superior activity to the conventional chemical pesticide and biopesticide with IE₅₀ of 0.02 mg/L. Nine compounds exhibited over 2-fold higher bioactivity against Aphis craccivora growth than (S)-methoprene. The physicochemical property evaluation and toxicological test showed that the potent (S)-methoprene derivatives were low toxic to the nontarget organism and the environment. Molecular docking studies further demonstrated that the high bioactivity of B2 may be partially attributed to its great affinity for binding to juvenile hormone receptors of P. xylostella. The current study suggests that B2 is a biochemical pesticide candidate with potency to be developed as a new agrochemical for lepidopteran control.