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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., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Fluorinated organic compounds represent a growing and important family of commercial chemicals. Introduction of fluorine into active ingredients has become an effective way to develop modern crop protection products. Given the particular properties of fluorine and high efficiency and selectivity of diamide insecticides, we designed and synthesized 27 anthranilic diamides analogues containing fluoro-sustituted phenylpyrazole. A preliminary bioassay indicated that most target compounds exhibited good biological activity against Mythimna separata and Plutella xylostella . Compound IIIf containing a 2,4,6-trifluoro-substituted benzene ring showed 43% insecticidal activity against M. separata at 0.1 mg L -1 , while the control chlorantraniliprole was 36%. The activity of IIIe against P. xylostella at 10 -5 mg L -1 was 94%, compared with that of the control being 70%. Thus, introduction of fluorine into diamide insecticides was useful for increasing activity. Insect electrophysiology studies showed that the calcium concentration in the nerve cells of third M. separata larvae was elevated by IIIf , which further confirmed that ryanodine receptor (RyR) was its potential target.

Main observation and conclusion: To search for potent insecticides targeting at ryanodine receptors (RyRs), a series of novel anthranilic diamides analogs containing 4‐chlorine N‐pyridylpyrazole were designed and synthesized. Their insecticidal activities were evaluated and the preliminary structure‐activity relationships (SARs) were discussed. The insecticidal results showed that some of the compounds (8a—8h, 8m, 8n) exhibited good larvicidal activities against oriental armyworm at 2.5 mg·L–1, and compound 8m possessed 60% insecticidal activity at 0.5 mg·L–1. For diamondback moth, 8m exhibited better activity than Chlorantraniliprole at a hundred fold preference. The calcium imaging technique experiment results suggested that compound 8m could increase the intracellular [Ca2+]i. With the neurons preincubated experiment, the results confirmed that the target of this series of compounds could be RyRs in the central larvae neurons of oriental armyworm. The results indicated that compound 8m could respond as a potential modulator of the insect ryanodine receptor. [ABSTRACT FROM AUTHOR]