Synthesis, biological activities, and SAR studies of novel 1-(2-chloro-4,5-difluorophenyl)-1H-pyrazole derivatives.

In order to search for the new ryanodine receptor (RyR) regulator, a series of 35 novel fluoro-substituted compounds introduced 1-(2-chloro-4,5-difluorophenyl)-1H-pyrazole moiety containing modified pyrazole heterocycle were designed and synthesized. Then, they were tested for the insecticidal activities against Mythimna separata and Plutella xylostella in our greenhouse. After a systematic biological screening, it was found out that IVc showed 50% larvicidal activities against Mythimna separata at 0.1 mg L-1, equivalent to that of chlorantraniliprole (36%, 0.1 mg L-1). The activity of IVc against Plutella xylostella was 90% at 10-5 mg L-1, whereas the chlorantraniliprole was 70% at the same concentration. Then, insect electrophysiology experiments were conducted to study the pattern of action of IVc and IVe. It was confirmed by the experimental results that both compounds could lead to the release of calcium from the endoplasmic reticulum of neurons as classical anthranilic diamide insecticides.