Design,synthesis, and insecticidal bioactivities evaluation of pyrrole- and dihydropyrrole-fused neonicotinoid analogs containing chlorothiazole ring

Chlorothiazole ring, as a substituted heterocycle, frequently occurred in structures of various insecticides, and brought positive effect on bioactivity. In purpose to find novel neonicotinoids, a series of pyrrole- and dihydropyrrole-fused neonicotinoid analogs containing chlorothiazole ring were synthesized for the first time. Results of the following biological assays showed that compounds 5a-c achieved good insecticidal activity against Aphis craccivora, and compound 5h exhibited good activity against Nilaparvata lugens.     

Design, synthesis and insecticidal activity of novel anthranilic diamides with benzyl sulfide scaffold

A series of novel anthranilic diamides with benzyl sulfide scaffold were synthesized,in which N-pyridylpyrazole moiety generally regarded as key pharmacophore was abandoned.The target compounds were characterized by ¹H NMR,¹³C NMR,¹⁹F NMR and HRMS.The preliminary bioassays indicated that half of the title compounds were endowed with good insecticidal activities against armyworm（Mythimna sepatara） at the concentration of 500 mg/L,Exhilaratingly,the synthesized compound 3a was also active against Tetranychus cinnabarinus at 100 mg/L.The difference in activities between the target compounds was influenced by the substituents,which provided some hints for further investigation on structure modifications.     

Design,synthesis and insecticidal activity of spiro heterocycle containing neonicotinoid analogs

Spiro heterocycles frequently occur in bioactive molecules. In the pursuit of neonicotinoids with spiro hererocycles, three types of novel neonicotinoids with spirobenzofuranone, spirooxindole or spiroacenaphythylenone framework were designed and synthesized. Insecticidal evaluation showed that some of spirobenzofuranone containing neonicotinoids exhibited moderate activity against cowpea aphid, armyworm or brown planthopper.     

Synthesis,insecticidal activity and molecular docking study of clothianidin analogues with hydrazide group

A series of novel neonicotinoid analogues were designed and synthesized by introducing a hydrazide group into clothianidin. Their structures were confirmed by IR, 1H NMR, and HRMS （ESI）. Preliminary bioassay showed that some compounds, Sb and Sg, exhibited good activity against soybean aphids （Aphis glycines） at 100 mg L ^-1. In addition, molecular docking with receptor was carried out to explain their different activity from clothianidin.     

Synthesis and insecticidal activities of novel bridged-neonicotinoids

A series of novel bridged-neonicotinoid analogues were designed and synthesized, which were constructed by starting material 8 with cyclopentenone or cyclohexenone in the presence of catalyst aluminium chloride. All of the compounds were characterized and confirmed by ¹H NMR, ¹³C NMR, HRMS and IR. The bioassay tests showed that compounds 5 and 6a showed higher bioactivities than imidacloprid against Aphis craccivora.     

Design,Synthesis and Insecticidal Activities of Novel 5-Alkoxyfuran-2(5H)-one Derivatives

A series of novel 5?alkoxyfuran-2(5H)-one derivatives was synthesized, and characterized by 1H NMR, 13C NMR and HRMS. Biological activities of all the title compounds were evaluated systematically. Preliminary bioassays indicated that most of the compounds exhibited moderate insecticidal activities against Aphis craccivora and Nilaparvata lugens at 100 mg/L. Compounds 4h and 4w exhibited 100% mortality rate against Aphis craccivora at 100 mg/L, and compound 4h exhibited good mortality rate against Aphis craccivora and Nilaparvata lugens (60% and 75%, respectively) even at 4 mg/L. The results demonstrated the impact of various chemical groups on insecticidal activities and provided a potential clue for further exploring novel high-effective broad-spectrum insecticides.     

Design,synthesis and insecticidal activities of novel anthranilic diamides containing polyfluoroalkyl pyrazole moiety

In order to discover new molecules with good insecticidal activities, a series of anthranilic diamides containing polyfluoroalkyl pyrazole were designed and synthesized, and their structures were characterized by ¹H NMR and HRMS. Bioassays demonstrated that some of the title compound exhibited excellent insecticidal activities. The larvicidal activities of compound 8a, 8c, 8g, 8k and 8l against Mythimna separata Walker were 100% at 0.8 mg/L. The insecticidal activities of compound 8a, 8c, 8e, 8g, 8k and 8l against Plutella xylostella Linnaeus were 100% at 0.4 mg/L. Surprisingly compounds 8a and 8c still showed 100% larvicidal activities against Plutella xylostella Linnaeus at 0.08 mg/L comparable to the commercialized Chlorantraniliprole. The LC₅₀ of compound 8a and 8c against M. separata is 0.048 and 0.043 mg/L respectively.     

The thiazoylmethoxy modification on pyrazole oximes Synthesis and insecticidal biological evaluation beyond acaricidal activity

A series of new pyrazole oximes bearing substituted thiazole ring were designed and prepared. The structures of the title compounds were identified by spectral analyses, The results of primary bioassay indicated that some targeted compounds exhibited promising insecticidal activity besides acaricidal activity, particularly; compounds 8c and 8d were more potent against Tetranychus cinnabarinus and Plutella xylostella than other analogues.     

取代喹啉类化合物抗菌活性的定量构效关系及分子设计

采用密度泛函理论(DFT)和逐步回归分析法对15种新合成的取代喹啉类化合物进行了定量构效关系(QSAR)研究. 在B3LYP/6-31G(d,p)水平上计算了取代喹啉的量子化学参数, 通过逐步多元回归分析筛选出影响抗菌活性的主要因素, 建立了定量构效关系方程, 并用留一法交叉分析了模型的稳定性及预测能力. 结果表明, C5的亲核电子密度fNC5及C9-N1的键级BC9-N1是影响喹啉类化合物抗金黄色葡萄球菌活性的主要因素, 所得模型对该类化合物抗菌活性有较好的预测效果. 同时基于QSAR研究结果设计了4个活性较高的新喹啉衍生物.     

Design, synthesis and antitumor activity of a series of novel coumarin-stilbene hybrids, the 3-arylcoumarins

A series of novel coumarin-stilbene hybrids called 3-arylcoumarins were synthesized via Perkin reaction and evaluated as potential antitumor agents. The results showed that some compounds exhibited in vitro activity against KB, KV, MCF-7, MCF-7/ADR cell lines to some extent. Compound 3a showed remarkable effect against KB tumor cells with an IC50 value of 5.18 μmol/L.     

Design,synthesis and insecticidal activity of biphenyl-diamide derivatives

Diamides acting on insect ryanodine receptors are an intensive research area now. In order to search for novel candidates, a series of diamides containing biphenyl substructure were designed and synthesized.Their insecticidal activities against armyworms(Mythimna sepatara) and aphis(Aphis craccivora) were screened. The compounds with 3,5-dichloro-4-(1,1,2,2-tetrafluoroethoxy)phenyl substituent were found to be insecticidal to armyworms with the similar symptoms to poisoning by flubendiamide. In this research, we presented a novel type of diamide insecticide as a lead compound for further optimization.     

Novel pyrethrin derivatives containing hydrazone and 1,3,4-oxadiazole thioether moieties: Design,synthesis, and insecticidal activity

Abstract

A series of novel pyrethrin derivatives containing hydrazone and 1,3,4-oxadiazole thioether moieties were designed, synthesized, and evaluated for their insecticidal activity. Bioassays indicated that some of the target compounds exhibited good insecticidal activities against Plutella xylostella (P. xylostella), Vegetable aphids (V. aphids), and Empoasca vitis (E. vitis). In particular, compound (E)-2-((5-(2,2-dimethyl-3-(2-methylprop-1-en-1-yl)cyclopropyl)-1,3,4-oxadiazol-2-yl)thio)-N'-(4-(trifluoromethyl)benzylidene)acetohydrazide (6s) revealed excellent insecticidal activities against P. xylostella, V. aphids, and E. vitis with the 50% lethal concentration (LC₅₀) values of 5.23, 7.07, and 1.61?mg/L, respectively, which were similar to or even better than those of chlorpyrifos, beta cypermethrin, spinosad, and azadirachtin. These results indicated that novel pyrethrin derivatives containing hydrazone and 1,3,4-oxadiazole thioether moieties could be developed as novel and promising insecticides.     

Design,synthesis and insecticidal activities of novel 1-substituted-5-(trifluoromethyl)-1H-pyrazole-4-carboxamide derivatives

A series of novel 5-(trifluoromethyl)-1H-pyrazole-4-carboxamide derivatives(6a–6n, 7a, 7b, and 8a-8f)were synthesised by placing the amide bond at the 4-position of the pyrazole ring. These derivatives differed from the structure of chlorantraniliprole analogues with the amide bond at the 5-position of the pyrazole ring. Preliminary bioassay results revealed that a few title compounds exhibited good insecticidal activities against lepidopteran pests, such as Plutella xylostella, Mythimna separate, Heliothis armigera, and Ostrinia nubilalis. Some title compounds also elicited broad-spectrum insecticidal activities against dipterous insects including Culex pipiens pallens after altering the amide position. Similar to pyrazole-5-carboxamide analogues, compounds 6b and 6e showed 100% insecticidal activity against P. xylostella, C. pipiens pallens, and M. separate at concentrations of 200, 2, and 200 mg/m L, respectively.This finding suggested that 5-(trifluoromethyl)-1H-pyrazole-4-carboxamide derivatives are potential alternative insecticides for management of agriculture pests.     

Syntheses and Biological Activities of Novel 3-Bromo-1-（3-chloropy- ridin-2-yl）-N-hydroxy-N-aryl- 1H-pyrazole-5-carboxamides

A series of novel 3-bromo-1-（3-chloropyridin-2-yl）-N-hydroxy-N-aryl-lH-pyrazole-5-carboxamides was synthesized by the reaction of pyrazole carbonyl chloride with each of substituted phenylhydroxyamines. The latter ones were prepared in good yields by reducing substituted nitrobenzene compounds with Zn/NH4CI reductant system in alcohol. Structures of the title compounds were determined by IR, 1H NMR, and HRMS. Their insecticidal and fungicidal activities were evaluated by larvicidal test against oriental armyworm and the mycelium growth rate method, respectively.     

An efficient synthesis of 3′-quinolinyl substituted imidazole-5-one derivatives catalyzed by zeolite and their antimicrobial activity

A series of some new quinoline based imidazole-5-one derivatives have been synthesized by the fusion of oxazol-5-ones,various p-substituted anilines and zeolite in pyridine.All the derivatives were subjected to an in vitro antimicrobial screening against a representative panel of bacteria and fungi and results worth further investigations.     

Separation,interconversion, and insecticidal activity of the cis‐ and trans‐isomers of novel hydrazone derivatives

A series of cis‐ and trans‐isomers of hydrazone derivatives were separated and analyzed through HPLC with diode‐array detection and HPLC‐MS/MS using ESI and ion trap MS. Two single crystals (A‐5‐1 and C‐2‐1) of the trans‐isomers were obtained and determined using X‐ray crystallography data, and the cis‐ to trans‐isomerization under different conditions was discussed. Both of the cis‐ and trans‐isomers of A‐4 and A‐5 exhibited good insecticidal activities against Plutella xylostella.     

Design,synthesis and insecticidal activities of novel anthranilic diamides containing fluorinated groups as potential ryanodine receptors activitors

In order to search for novel potent and environmentally benign insecticides, a series of anthranilic diamides containing various fluorinated groups were designed and synthesized. Their structures were confirmed by ¹H NMR, ¹³C NMR, ¹⁹F NMR, elemental analysis, HRMS or mass spectra. Their insecticidal activities against oriental armyworm (Mythimna separata) and diamondback moth (Plutella xylostella) were evaluated. The preliminary structure-activity relationship (SAR) was discussed in detail. The biological assay indicated that most of the compounds exhibited moderate to excellent insecticidal activities. Especially, Ia showed high larvicidal activity against oriental armyworm. Meanwhile, Iu had better larvicidal effects against diamondback moth than commercial chlorantraniliprole.     

Facile three-component synthesis and insecticidal evaluation of hexahydroimidazo[1,2-a]pyridine derivatives

A series of new hexahydroimidazo[1,2-α]pyridine derivatives were synthesized via convenient and practical three-component reactions.Preliminary bioassays showed that majority of the target compounds exhibited moderate to excellent insecticidal activity against cowpea aphids(Aphis craccivora).Among them,compound 91 demonstrated significant activity with LC_(50) value of0.00918 mmol/L which was about 3.8-fold higher than that of imidacloprid(IMI).Furthermore,the study of stereostructure-activity relationship of four isomers of 9k indicated that configuration played a key role in insecticidal activity of these compounds.     

Design,synthesis and antibacterial activity of novel 1-oxacephem analogs

A series of l-oxacephem analogs were synthesized and their antibacterial properties against five strains of Gram-positive and Gram-negative bacteria were evaluated in vitro while ceftazidine was selected as control. Some of the tested compounds, compound 2c in narticular,showed more active aeainst three selected strains than the standard.