Rational Design of Photoactivatable Avermectin Derivatives Enabling Root-Mediated Translocation and Foliar...

Avermectin degrades rapidly under UV light, limiting its field efficacy to 3-5 days. This necessitates frequent reapplication, increasing costs and raising concerns about residues and ecological risks. In this study, a novel class of photoactivatable avermectin derivatives was synthesized via structural modification by introducing an o-nitrobenzyl group. The aim was to enhance systemic translocation following root application by improving compound mobility within the plant─thereby preventing rapid photodegradation under light exposure, and achieving a sustained-release effect. Based on insecticidal activity studies and transport experiments, this study developed two highly active derivatives. These compounds not only maintain high insecticidal activity but also, according to their enhanced systemic mobility and sustained concentration profiles observed in plants, show the potential to significantly prolong the effective duration in practical applications. Computational chemistry analyzed both the photodegradation mechanism of o-nitrobenzyl ester and the interactions of its derivatives with target proteins.