Synthesis and bioactivity of fipronil derivatives modified with phosphate esters and carbamates

Six novel compounds were synthesized by incorporating phosphate esters and carbamates into fipronil through substructure link principle.Their structures were confirmed by 1H NMR and 13C NMR spectra,ESI-MS,as well as elemental analysis.The results of preliminary insecticidal activity tests and toxicity tests showed that the novel compounds possessed good activity against Spodoptera litura and Ostrinia furnacalis.In particular,compounds 1 and 2 exhibited better activity against O.furnacalis than fipronil,LC50 value was 0.85 μ g/mL and 2.01 μ g/mL,respectively.Their toxicity against Apis mellifera L. were lower than fipronil.