For the first time we experimentally proved that the G4946E mutation in PxRyR confers resistance to chlorantraniliprole in Plutella xylostella. These findings pave the way for the complete understanding of the mechanisms of diamide insecticides resistance in insects.

The first cobalt-catalyzed asymmetric Kumada cross-coupling with high enantioselectivity has been developed. The reaction affords a unique strategy for the enantioselective arylation of α-bromo esters catalyzed by a cobalt-bisoxazoline complex. A variety of chiral α-arylalkanoic esters were prepared in excellent enantioselectivity and yield (up to 97% ee and 96% yield). The arylated products were transformed into α-arylcarboxylic acids and primary alcohols without erosion of ee. The new enantioenriched α-arylpropionic esters synthesized herein are potentially useful in the development of nonsteroidal anti-inflammatory drugs. This method was conducted on gram-scale and applied to the synthesis of highly enantioenriched (S)-fenoprofen and (S)-ar-turmerone.

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Fluobendiamide is the first commercialized artificial synthetic insecticide acting on the ryanodine receptor. This new molecule possesses a combination of excellent insecticidal activity and eco-friendly characteristics with a skeleton structure of phthalamide. In this study, we incorporated hydrazone, present in many pesticidal compounds reported during the last two decades, into phthalamide derivatives via Schiff-base condensation and aminolysis to obtain 21 new compounds; these compounds were characterized by proton nuclear magnetic resonance ((1)H NMR), infrared spectroscopy (IR), and high-resolution mass spectrometry (HRMS) or elemental analysis. A preliminary bioassay against peach aphids ( Myzus persicae ) revealed that the title compounds exhibited good stomach toxicity at 600 mg/L. Twelve new compounds were found to display higher activity than postive control flubendiamide (LC(50) = 184.099 mg/L), however, LC(50) was less than 100 mg/L only for compounds 4e, 4o, 4s, 4t (59-77 mg/L). That is, combinations of a p-fluorophenyl or (methyl)thienyl group at the Ar position with an isopropyl or cyclohexyl group at the R position might improve the lethality of the designed phthalamide derivative. Preliminary results of a bioassay at 600 mg/L against diamondback moth ( Plutella xylostella , Linnaeus) showed that only the title compound 4e possessed good larvicidal activity. On comparison of the bioassay results of stomach toxicity and larvicidal activity, it is noteworthy that the compound incorporating phenylpyrazolyl exhibited good larvicidal activity and poor stomach activity.

An enzyme-linked immunosorbent assay (ELISA) was developed for the neonicotinoid insecticide thiamethoxam, 3-(2-chlorothiazol-5-ylmethyl)-5-methyl-4-nitroimino-1,3,5-oxadiazinane. Three antisera were raised from rabbits immunized with the hapten-KLH conjugate. On the basis of the computational analysis of hapten candidates, the hapten with a spacer arm on the thiazolyl ring of thiamethoxam was synthesized to elicit thiamethoxam-specific antisera. The hapten was 3-[2-(2-carboxyethylthio)-5-ylmethyl]-5-methyl-4-nitroimino-1,3,5-oxadiazinane. Antisera were characterized with indirect competitive ELISA. Cross-reactivity and effects of organic solvents, pH, and ionic strengths were evaluated. The antiserum was specific for thiamethoxam and tolerant of up to 5% acetonitrile and 5% acetone. Various ionic strengths and pH values in the tested ranges had negligible effect on the assay performance. Under the optimized conditions, the half-maximal inhibition concentration (IC(50)) and the limit of detection were approximately 9.0 and 0.1 microg/L of thiamethoxam, respectively. ELISA analysis of stream and tap water samples showed an excellent correlation with the fortification levels.