Light-induced activities of novel naphtho[1,8-ef]isoindole-7,8,10(9H)-trione and oxoisoaporphine derivatives towards mosquito larvae

Abstract

Infected mosquitoes are significant vectors of dengue, yellow fever, chikungunya, zika and other pathogens. In the view of increasing resistance in mosquito larvae control, photoactivated insecticides is a promising approach by utilizing highly toxic singlet oxygen produced by photosensitizer through irradiation. However, the choice of photosensitizer for mosquito control is limited. Here, we report a novel series of naphtho[1,8-ef]isoindole-7,8,10(9H)-trione and oxoisoaporphines derivatives as excellent type II photosensitizers. Meanwhile, the light-dependent activities against permethrin-susceptible and permethrin-resistant strain of Aedes aegypti mosquito larvae of these compounds were evaluated. Among them, compound 7b was proved to be potential photodynamic insecticide due to its excellent phototoxicity, the LC50 value was 0.19 μg mL−1 under visible light irradiation. The irradiation-generated enhancement in the activity was more than 520-fold. This compound could be the potential candidate in the search for new photoactivated insecticide leads. Importantly, 7b has good fluorescence quantum yield (ϕF = 0.70), it can be used as a fluorescence indicator in mosquito larvae to observe uptake and morphology change.