Design, synthesis, and biological activities of novel camphoric acid derivatives bearing α -aminophosphonate moiety

In light of the broad-spectrum biological activities of camphor and α-aminophosphonate, a series of camphor acid derivatives incorporating α-aminophosphonate moieties were rationally designed, synthesised, and evaluated for their biological activities. The target compounds were characterised using IR,¹H NMR,¹³C NMR, and ESI-MS techniques. Preliminary bioassays revealed compound 5a displayed a 93.7% inhibitory effect, while compound 5i showed a 96.2% inhibitory effect against B. dothidea when tested at a concentration of 50 mg/L, much better than that of the positive control Chlorothalonil. Herbicidal evaluations revealed that at 100 mg/L, the growth inhibition rates of compounds 5a, 5c, 5f, and 5h on the roots of rape (Brassica campestris) were 81.5%, 82.8%, 81.2%, and 96.6%, respectively, much better than that of the positive control Flumioxazin. Preliminary insecticidal assays suggested that the introduction of α-aminophosphonate significantly enhanced the insecticidal activity of the parent compound. This investigation establishes a proof-of-concept foundation, indicating that the drug design strategy could be effectively applied in agrochemical research.