Design, synthesis and bioassay of the emerging photo-responsive fungicides

Precise and spatiotemporal control over the pesticide remains to be a challenge. More efficient controlled release systems (CRSs) have been developed to support the precise delivery of active ingredients. Herein, we incorporated the photoremovable protecting groups (PRPGs) into phenamacril (PHE) and obtained two photo-responsive fungicides of NV-PHE and DEACM-PHE. The 4,5-dimethoxy-o-nitrobenzyl (NV) or 7-diethylaminocoumarin (DEACM)-caged PHE could release the active molecule PHE after irradiation of UV light and blue light, respectively. Optical properties and in-vitro/vivo fungicidal activities of NV-PHE and DEACM-PHE demonstrated the feasibility for light controlled release of PHE. DEACM-PHE could release 98% PHE by illumination of blue light. The irradiated DEACM-PHE could preserve the similar bioactivity of PHE, and significantly improve the in-vitro/vivo fungicidal activities compared to the non-irradiated DEACM-PHE. The optical controlled release of PHE from DEACM-PHE enabled the precise and spatiotem-poral delivery of PHE, diversifying the development of CRSs for pesticide, and providing environment -friendly agricultural applications with high pesticide efficiency.& COPY; 2023 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.