Natural Product-Based Pesticide Discovery: Design, Synthesis and Bioactivity Studies of -Amino-Maleimide Derivatives.

Natural products are an important source of pesticide discovery. A series of -amino-maleimide derivatives containing hydrazone group were designed and synthesized based on the structure of linderone and methyllinderone which were isolated from Makino. According to the bioassay results, compounds and showed 60% inhibition against mosquito () at 0.25 µg·mL. Furthermore, the results of antifungal tests indicated that most compounds exhibited much better antifungal activities against fourteen phytopathogenic fungi than linderone and methyllinderone and some compounds exhibited better antifungal activities than commercial fungicides (carbendazim and chlorothalonil) at 50 µg·mL. In particular, compound exhibited broad-spectrum fungicidal activity (>50% inhibitory activities against 11 phytopathogenic fungi) and compounds and displayed 60.6% and 47.9% inhibitory activity against at 12.5 µg·mL respectively. Furthermore, compound was synthesized, which lacks N-substituent at maleimide and its poor antifungal activity against and at 50 µg·mL showed that the backbone structure of -amino-maleimide derivatives containing hydrazone group was important to the antifungal activity.