Diamide derivatives containing a trifluoromethylpyridine skeleton:Design,synthesis,and insecticidal activity

Diamide derivatives are biologically active molecules that have been widely applied in recent years in research on pesticides,especially insecticides.Using a simple and environmentally friendly scheme,a series of new diamide derivatives containing a trifluoromethylpyridine skeleton was designed,synthesized,and confirmed by^(1)H,^(19)F and^(13)C NMR,and HR-MS.Their insecticidal activities against Plutella xylostella and Helicoverpa armigera were measured and the relationship between structure and activity was investigated.Eight of the title compounds(D2,D5,D10,D21,D28,D29,D30 and D33)showed 100%activity against P.xylostella at 500 mg L^(-1).One compound,D33,still showed 100%activity against P.xylostella at 100 mg L^(-1)and had the lowest LC_(50)(lethal concentration 50%,3.7 mg L^(-1))among the synthesized compounds.Molecular docking analysis revealed that D33 could be thoroughly embedded in the active pocket of the ryanodine receptor via hydrogen bonding in a manner similar to the commercial insecticide chlorantraniliprole.

Enhancing boll protein synthesis and carbohydrate conversion by the application of exogenous amino acids at the peak flowering stage increased the boll Bt toxin concentration and lint yield in cotton

In Bacillus thuringenesis(Bt) transgenic cotton, the cotton boll has the lowest insecticidal protein content when compared to the other organs. The present study investigated the effects of amino acid spray application at the peak flowering stage on the cotton boll Bt toxin concentration and yield formation. Boll protein synthesis and carbohydrate conversion were also studied to reveal the fundamental mechanism. Three treatments(i.e., CK, the untreated control;LA1, five amino acids;LA2, 21 amino acids) were applied to two Bt cultivars of G. hirsutum(i.e., the hybrid Sikang 3 and the conventional Sikang 1) in the cotton-growing seasons during 2017 and 2018. Amino acid spray application at the peak flowering stage resulted in an increase of 5.2–16.4% in the boll Bt protein concentration and an increase of 5.5–11.3%in the seed cotton yield, but there was no difference between the two amino acid treatments. In addition, amino acid applications led to increases in the amino acid content, soluble protein content, glutamate pyruvate transaminase(GPT)activity, glutamate oxaloacetate transaminase(GOT) activity, glucose content, fructose content and soluble acid invertase(SAI) activity. This study also found that Bt protein content, enhanced boll number and the weight of opened bolls were closely related to carbon and nitrogen metabolism. The Bt protein content had significant linear positive correlations with amino acid and soluble protein contents. Enhanced boll number had significant linear positive correlations with the GPT and GOT activities from 15–25 days after flowering(DAF). The weight of opened bolls from 55–65 DAF had a significant linear positive correlation with the SAI activity. These results indicate that the enhancement of boll protein synthesis and carbohydrate conversion by amino acid application resulted in a simultaneous increase in the boll Bt protein concentration and cotton lint yield.

Synthesis of 4″-benzyloxyimino-4″-deoxyavermectin Bla derivatives

Six new 4＂-benzyloxyimino-4＂-deoxyavermectin B la derivatives were synthesized from avermectin Bla by the selective protection of C-5-hydroxy group, oxidation of C-4＂-hydroxy group, and deprotection followed by reaction with O-substituted hydroxylamine hydrochlorides. Their structures were confirmed by IR, 1H NMR, 13C NMR and MS. Insecticidal activities of the derivatives against Phopalosiphum pseudobrassicae, Spodoptera exigua and Pluteua xylosteua were evaluated.

Synthesis,Crystal Structure and Insecticidal Activity of N-(pyridin-2-ylmethyl)-1-phenyl-1,4,5,6,7,8-hexahydrocyclohepta[c]pyrazole-3-carboxamide

The title compound N-（pyridin-2-ylmethyl）- 1-phenyl- 1,4,5,6,7,8-hexahydrocy-clohepta[c]pyrazole-3-carboxamide 5 （C21I-I22N40, Mr = 346.42） has been synthesized andstructurally characterized by IR, 1H NMR, 13C NMR, H RMS and single-crystal X-raydiffraction. The crystal crystallizes in monoclinic system, space group P21/n with a = 8.668（2）,b = 22.236（4）, c = 9.539（2） A, β = 108.68（3）°, V = 1786.4（7）/k3, Z = 4, Dx= 1.288 g/cm3,F（000） = 736,μ（MoKa） = 0.649 mm^-1, the final R = 0.0354 and wR = 0.0933 with 3234observed reflections with I 〉 2σ（/）. The benzene and pyrazole rings are nearly coplanar with adihedral angle of 50.977（46）°. The dihedral angle between the central pyrazole and pyridinerings is 11.688（46）°. No classical hydrogen bonds were found in the molecules. Two adjacentmolecules in crystal packing of compound 5 were linked by two intramolecularhydrogen-bonding interactions C（15）-H（15）…O（1） to generate a stable structure. Compound 5had weak insecticidal activity against the diamondback moth （Plutella xylostella）, butexhibited good activity against cotton bollworm （Helicoverpa armigera）.

Synthesis of New 13-O-Acylavermectin Bl Aglycones

Six new 13-O-acylavermectin Bl aglycones(3-8) were synthesized from avermectin B1 aglycone and their bioactivities were evaluated against Spodoptera exigua, Spodoptera eridania, Tetranychus urticae and Aphis fabae.

Synthesis and Crystal Structure of 2-Ethoxycarbonylmethyl-8-chloro-3a,4-dihydro-3a-methyl-chromeno[4,3-c]pyrazol-3(2H)-one

The crystal structure of the title compound 2-ethoxycarbonylmethyl-8-chloro-3a,4-dihydro-3a-methyl-chromeno[4,3-c]pyrazol-3（2H）-one（C15H15ClN2O4,Mr = 322.74） has been prepared and determined by single-crystal X-ray diffraction.The crystal is of orthorhombic,space group Pccn with a = 16.7246（10）,b = 19.6626（12）,c = 9.3013（6） ,V = 3058.7（3） 3,Z = 8,Dc = 1.402 g/cm3,μ = 0.269 mm-1,F（000） = 1344,the final R = 0.0506 and wR = 0.1464 for 2568 reflections with I 〉 2σ（I）.In addition,disordered C（14） and C（15） atoms exist in the crystal structure.

Study on Chemical Synthesis and Insecticidal Activity of Peptideκ-CTx-btg02

[Objectives]This study was conducted to investigate the chemical synthesis of peptideκ-CTx-btg02.[Methods]Linear peptideκ-CTx-btg02 was synthesized by solid phase peptide synthesis(SPPS).After oxidation and folding of the linear peptide,mass spectrometry identification and high performance liquid chromatography(HPLC)purification were performed.Then,the MTT method and insect injection method were applied to study its insecticidal activity.[Results]The peptideκ-CTx-btg02 was successfully synthesized by the SPPS method,and identified for the formation of disulfide bonds by mass spectrometry identification,and the purity after HPLC separation was greater than 95%.The MTT experiment showed that the peptideκ-CTx-btg02 could inhibit the growth of insect cells sf9,with a half effective dose of 0.13 nM.The insect injection experiment showed that the peptideκ-CTx-btg02 could effectively kill Tenebrio molitor,with a half lethal dose of 15.6 nM.The results of the electrophysiological experiment showed that 10μM peptideκ-CTx-btg02 had no blocking activity on murine acetylcholineα2β3 andα3β4.Therefore,the peptideκ-CTx-btg02 had a good inhibitory effect on the growth of insect cells,highly effective insecticidal activity and weak mammalian toxicity.[Conclusions]This study lays a foundation for the development of new,safe and efficient peptide biological insecticides.

Synthesis of 5-[5-(α-Naphthyl)-2H-Tetrazol-2-Methylene]-2-Aroylamino-1, 3,4-Thiadiazoles

Introduction Acylthiosemicarbazides have been reported to possess extensive physiological activities. Substituted thiadiazoles are known to exhibit fungicidal and insecticidal activities. Chen Limin and her coworkers reported that the cyclization of 1[5-(3’-pyridyl )-2H-tetrazol-2-acetyl-]-4-acylthiosemicarbazides gave 5-[5-(3’-

Synthesis and Crystal Structure of Cis 2-(6- Chloro-3-pyridylmethylamino)-4-chlorophenyl- 5,5-dimethyl-1,3,2-dioxaphosphinane 2-Oxides

The crystal structure of the title compound (C17H19Cl2N2O3P, Mr = 401.21) has been determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 6.1648(6), b = 19.943(2), c = 15.268(2) ?, β = 99.220(2)°, V = 1852.8(3) ?3, Z = 4, Dc = 1.438 g/cm3, F(000) = 832, μ(MoKα) = 0.456 mm-1, the final R = 0.0622 and wR = 0.1586 for 3986 observed reflections (I > 2σ(I)). X-ray analysis reveals that the product is a thermodynamically stable cis isomer. The intramolecular hydrogen bond N(2)–H(2A)…O(1) is observed in the title compound.

Synthesis analogues of milbemycin and their bioactivity evaluation

Eight new 13-O-aminocarbonylivermectin aglycones and 4＇-O-aminocarbonylivermectin monosaccharide were synthesized from ivermectin agiycone and ivermectin monosaccharide by the selective protection of C5-OH group.Their bioactivities were evaluated against spider mites（Tetranychus cinnabarimts）,aphid（Aphis fabae） and oriental armyworm（Mytliimma sepatara）. Their structures were confirmed by ^1H NMR.MS.

Synthesis of 5-Deoxy-5-Acyloxyiminoavermectin B1 Derivatives

Four 5-deoxy-5-acyloxyiminoavermectin B1 derivatives 4a^d were synthesized via three steps from avermectin B1 and their biological activities were tested against Heliothis armigera, Laphygma exigua and Musca domestica.

Synthesis and Crystal Structure of N-((6-chloropyridin-3-yl)methyl)-6-ethoxy-N-ethyl-3-nitropyridin-2-amine

The title compound N-（（6-chloropyridin-3-yl）methyl）-6-ethoxy-N-ethyl-3-nitropyri-din-2-amine（4） was synthesized by reacting the mixture of 6-chloro-2-ethoxy-3-nitropyridine（1） and 2-chloro-6-ethoxy-3-nitropyridine（2） with 3,and its structure was determined by X-ray single-crystal diffraction.The crystal belongs to the monoclinic system,space group P21/n with a = 7.3441（2）,b = 9.9041（3）,c = 11.7368（3） ,α = 101.410（2）,β = 102.1340（10）,γ = 99.594（2）o,μ = 0.260 mm^-1,Mr = 336.78,V = 798.58（4）（A°）^3,Z = 2,Dc = 1.401g/cm^3,F（000） = 352,T = 296（2） K,R = 0.0210 and wR = 0.1053.

Chitin synthesis inhibitors： old molecules and new developments

Chitin is the most abundant natural aminopolysaccharide and serves as a structural component of extracellular matrices. It is found in fungal septa, spores, and cell walls, and in arthropod cuticles and peritrophic matrices, squid pens, mollusk shells, nematode egg shells, and some protozoan cyst walls. As prokaryotes, plants and vertebrates including humans do not produce chitin, its synthesis is considered as an attractive target site for fungicides, insecticides, and acaricides. Although no chitin synthesis inhibitor has been developed into a therapeutic drug to treat fungal infections in humans, a larger number of compounds have been successfully launched worldwide to combat arthropod pests in agriculture and forestry. This review summarizes the latest advances on the mode of action of chitin synthesis inhibitors with a special focus on those molecules that act on a postcatalytic step of chitin synthesis.

Design, Synthesis and Biological Activities of Novel Benzoyl Hydrazines Containing Pyrazole

In search of environmentally benign compounds with high biological activity, low toxicity and low resistance, 8 novel benzoyl hydrazines containing pyrazole were designed and synthesized. All compounds were characterized by I H NMR spectra and HRMS. The preliminary results of biological activity assessment indicated that most of title compounds exhibited certain insecticidal activities against M）,thimna separata Walker at 200 mg L-1 but excellent fungicidal activities against six fungus at 50 mg L-1, which were better than the control.

Synthesis, insecticidal activities and SAR studies of novel anthranilic diamides containing trifluoroethoxyl substituent and chiral amino acid moieties

Ryanodine receptors（RyRs） activator has become one class of popular insecticide because of its unique mode of action. In order to find more new RyRs activators as insecticidal agents, a series of 18 novel chiral anthranilic diamides were designed by introducing the D-alanine acid and D-serine acid esters as well as trifluoroethoxyl group into the anthranilic diamide skeleton and synthesized successfully based on anthranilic diamide and FKI-1033 structures. The structures of the title compounds Ia–i and IIa–i were confirmed by melting points,~1H NMR,^（13）C NMR, elemental analysis and specific optical rotation analysis.The preliminary bioassay results indicated that most of the title compounds exhibited considerable larvicidal activities against oriental armyworm at 10 mg/L, especially Ib, Ie and IIh showed remarkable insecticidal activities at 0.5 mg/L. The larvicidal activity against diamondback moth of Ia and IId were 80%and 90% respectively at 0.0001 mg/L, which was similar to that of chlorantraniliprole. The relationship between structure and insecticidal activity was analyzed to reveal a possible co-regulated effect of the chiral amino acid ester, halogen atom or cyano group, and trifluoroethyloxyl group of the skeleton structures of the title compounds, which will provide useful information for guiding the design and discovery of new RyRs activators and insecticidal agrochemicals.

Synthesis,insecticidal and acaricidal activities of novel 2-arylpyrroles

To search for novel 2-arylpyrroles with unique biological activities,a series of novel 2-arylpyrrole derivatives were designed and synthesized,and their structures were characterized by 1 H and 13 C NMR spectroscopy,MS spectrometry,and elemental analysis.Their insecticidal activities against Lepidopteran pests (e.g.Mythimna separata) and acaricidal activities against mites (e.g.Tetranychus urticae) were evaluated.The results of bioassays indicate that some of these title compounds exhibited excellent insecticidal and acaricidal activities.For example,4-bromo-1-((chloromethoxy)methyl)-2-(4-chloro phenyl)-5-(trifluoromethyl)pyrrole-3-carbonitrile (6a),4-bromo-2-(4-chlorophenyl)-1-((2-fluoroethoxy)-methyl)-5-(trifluoromethyl)pyrrole-3-carbonitrile (6d) showed insecticidal activity against Mythimna separata and 4-bromo-2-(4-chlorophenyl)1-((isopropoxymethoxy)methyl)-5-(trifluoro methyl)pyrrole-3-carbonitrile (7d) showed acaricidal activity against Tetranychus urticae.They were more effective than Chlorfenapyr,which has been the only commercialized member of a new class of chemicals of 2-arylpyrroles.

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,^（13）C NMR,^（19）F 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 1,5-Diphenyl-l-pentanone Analogues

Three series of novel 1,5-diphenyl-l-pentanone derivatives were designed and synthesized. Their structures were characterized by IR, IH NMR techniques, and elemental analysis. The insecticidal activities of the new compounds were preliminarily evaluated. The bioassay results indicated that the compounds Xll--X30 displayed better aphicidal activity against Aphis gossypii than compounds X1--X10 and the lead compound （E）-l,5-diphenyl-1- penten-1-one （A）. The inhibitory rates of compounds X6 and X29 were 100% against Plutella xylostella （L.） at 600 mgoL 1. Compounds X12, X13, X19, X24, X25, X26 and X27 showed higher insecticidal activity against Tetranychus cinnabarinus （Boisduval） at 600 mgoL 1 than the lead compound （A）. Keywords Stellera chamaejasme L, （E）-l,5-diphenyl-l-penten-l-one, analogue, synthesis, design, insecticidal activity

Synthesis and Insecticidal Evaluation of Novel Anthranilic Diamides Derivatives Containing 4-Chlorine Substituted N-Pyridylpyrazole

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 struc ture-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 activityat 0.5 mg·L^(-1).For diamondback moth,8m exhibited better activity than Chlorantraniliprole at a hundred fold preference.

Design, synthesis, insecticidal evaluation and molecular docking studies of cis-nitenpyram analogues bearing diglycine esters

Based on the strategies of receptor structure-guided neonicotinoid design, a series of novel cis-nitenpyram analogues bearing diglycine esters were designed and synthesized. Preliminary bioassays indicated that the insecticidal spectra of the target compounds were expanded compared with our previous work, while all the target compounds presented excellent insecticidal activities against Nilaparvata lugens and Aphis medicagini at 100 mg/L. Among these analogues, 6b showed 100% mortality against Nilaparvata lugens (LC 50 = 0.163 mg/L) and 90% against Aphis medicagini at 4 mg/L. SARs suggested that the insecticidal potency of our designed cis-nitenpyram analogues was dual-controlled by the size and species of the ester groups. The molecular docking simulations revealed that the structural uniqueness of these analogues may lead to a unique molecular recognition and binding mode compared with the previously designed compounds. Introduction of the peptide bond gave rise to more significant hydrogen bonds between the nitenpyram analogues bonding with the amino acid residues of insect nAChRs. The docking results explained the SARs observed in vitro, and shed light on the novel insecticidal mechanism of these cis-nitenpyram analogues.