Insecticide Activity and Structure, Insecticidal Properties of Some Diethyl Nitronaphthyl Phosphates

Abstract

The complete series of diethyl mononitro-1-naphthyl and mononitro-2-naphthyl phosphates, and a number of diethyl dinitronaphthyl phosphates, were synthesized and examined for hydrolysis rates, fly-brain cholinesterase inhibition, and toxicity to houseflies. The effect of the nitro group in the various available positions in the naphthalene nucleus on the general reactivity of the phosphorus atom was assessed, and a correlation between hydrolysis constants and a-constants derived from three different sources was made.Some of the compounds are exceptionally strong inhibitors of fly-brain cholinesterase.Toxicity to houseflies did not parallel anticholinesterase activity, indicating wide variability in the rates of in vivo detoxification of these compounds. Diethyl 6-nitro-2-naphthyl phosphate showed the highest toxicity to houseflies and is comparable in activity to paraoxon. NHIBITION of the cholinesterase en-