Synthesis and pesticidal activities of novel anthranilic diamides containing pyridylpyrazole and iminodithiocarbamate or thiosemicarbazone motifs

<p>A series of novel anthranilic diamide derivatives containing pyridylpyrazole and iminodithiocarbamate or thiosemicarbazone motifs were synthesized via multi-step reactions. The structures of seven title compounds (methyl 2-(2-(3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamido)-5-chloro-3- methylbenzylidene)hydrazinecarbodithioate <b>7</b> and 3-bromo-N-(2-((2-substitutedcarbamothioylhydrazono)methyl)-4-chloro-6-methylphenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide <b>8a-8f</b>) were confirmed by melting points, IR, ¹H NMR, ¹³C NMR, and HRMS. The bioassays showed that some of the compounds exhibited modest insecticidal activities against oriental armyworm (Mythimna separata Walker), particularly, compound <b>8b</b> (3-bromo-N-(4-chloro-2-methyl-6-((2-(methylcarbamothioyl)hydrazono)methyl)phenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide) held 100% and 30% larvicidal activity at the concentration of 25 mg/L and 10 mg/L, respectively. In addition, several compounds displayed favorable fungicidal activities against Alternaria solani Sorauer and Physalospora piricola at 50 μg/mL, and were comparable with the controls Chlorothalonil and Triadimefon. The results in this paper will provide important information for further research and development of sulfur-containing heterocyclic agrochemicals.</p

Synthesis and Fungicidal Activities of Novel 1,2,4-Triazole Thione Derivatives Containing 1,2,3-Triazole and Substituted Piperazine Moieties

<p>A series of novel 1,2,4-triazole thione derivatives containing 1,2,3-triazole and substituted piperazine moieties were synthesized via the Mannich reaction of 1,2,3-triazole-containing 1,2,4-triazole thiol intermediates with various substituted piperazines and formaldehyde in high yields. The structures of 14 title compounds were confirmed by melting points, IR, ¹H NMR, ¹³C NMR, and elemental analysis. The bioassay results showed that some of the title compounds exhibit significant fungicidal activities against several plant fungi at 50 μg/mL, especially trifluoromethyl-containing triazole thione derivative <b>9g</b> showed broad activities and could be made further structural optimization for novel fungicides innovation research.</p

Synthesis, Structure, and Biological Activities of [5-(Arylthio/sulfinyl/sulfonyl)-3-methyl-1-phenyl-1<i>H</i>-pyrazol-4-yl]-arylmethanones

<div><p>GRAPHICAL ABSTRACT</p><p></p></div

The Synthesis and Biological Activities of [5-(4-Substituted Phenylsulfinyl/Sulfonyl)-1,3-Dimethyl-1<i>H</i>-Pyrazol-4-Yl]-Arylmethanones

<div><p></p><p>A novel series of pyrazole derivatives containing substituted phenylsulfinyl/sulfonyl group have been synthesized via the oxidation of intermediate pyrazole sulfoether with H₂O₂ in acetic acid. The novel compounds were characterized by melting point, ¹H NMR, FT-IR, MS, and elemental analysis or HRMS. The biological activity results showed that most of the title compounds exhibit significant fungicidal activities against Alternaria solani Sorauer, Phytophthora capsici, and Corynespora cassiicola.</p> <p>[Supplementary materials are available for this article. Go to the publisher's online edition of <i>Phosphorus, Sulfur, and Silicon and the Related Elements</i> for the following free supplemental files: Additional text and figures.]</p> </div

Synthesis and biological activity of novel dimethylpyrazole and piperazine-containing (bis)1,2,4-triazole derivatives

<p></p> <p>A series of novel dimethylpyrazole and piperazine-containing (bis)1,2,4-triazole derivatives have been conveniently synthesized via Mannich reaction in good yields. Their structures were identified by IR, ¹H NMR, ¹³C NMR, and elemental analysis. The preliminary bioassays showed that among 14 new compounds, the trifluoromethyl-containing compounds exhibited superior activity than the methyl-containing ones; some of the compounds displayed significant in vitro and in vivo fungicidal activity against several plant fungi and were comparable with the control Triadimefon; several compounds exhibited certain herbicidal activity against <i>Brassica campestris</i>; several compounds possessed favorable KARI inhibitory activity, especially <b>8D</b> could be a promising KARI inhibitor for further study. The research results will provide useful information for the design and discovery of new agrochemicals with novel heterocyclic Mannich base structures containing piperazine moiety.</p

Synthesis and Insecticidal Activities of Novel Anthranilic Diamides Containing Acylthiourea and Acylurea

Two series of anthranilic diamides containing acylthiourea and acylurea linkers were designed and synthesized, with changed length and flexibility of the linkers to compare to known anthranilic diamide insecticides. In total, 26 novel compounds were synthesized, and all compounds were characterized by ¹H nuclear magnetic resonance and high-resolution mass spectrometry. Their insecticidal activities against oriental armyworm (Mythimna separata), mosquito larvae (Culex pipiens pallens), and diamondback moth (Plutella xylostella) were evaluated. The larvicidal activities against oriental armyworm indicated that the introduction of acylthiourea into some structures could retain their insecticidal activity; 8 of the 15 compounds (<b>13a</b>–<b>13e</b>, <b>14a</b>–<b>14e</b>, and <b>15a</b>–<b>15e</b>) exhibited 100% larvicidal activity at 10 mg/L. However, the introduction of acylurea decreased the insecticidal activity; only 3 of the 11 compounds (<b>17a</b>–<b>17k</b>) exhibited 100% larvicidal activity at 200 mg/L. The whole-cell patch-clamp technique indicated that compound <b>13b</b> and chlorantraniliprole exhibited similar effects on the voltage-gated calcium channel. The calcium-imaging technique was also applied to investigate the effects of compounds <b>13b</b> and <b>15a</b> on the intracellular calcium ion concentration ([Ca²⁺]_i), which indicated that they released stored calcium ions from endoplasmic reticulum. Experimental results denoted that several new compounds are potential activators of the insect ryanodine receptor (RyR)

Synthesis, Insecticidal Activities, and SAR Studies of Novel Pyridylpyrazole Acid Derivatives Based on Amide Bridge Modification of Anthranilic Diamide Insecticides

Anthranilic diamides are one of the most important classes of modern agricultural insecticides. To discover new structure-modified compounds with high activity, series of novel carbonyl thioureas, carbonyl ureas, oxadiazoles, carbonyl thiophosphorylureas, oxadiazole-containing amides, and thiazoline-containing amides were designed through the modification of the amide bridge based on the structure of chlorantraniliprole and were synthesized, and bioassays were carried out. The compounds were characterized and confirmed by melting point, IR, ¹H NMR, and elemental analyses or HRMS. Preliminary bioassays indicated that some compounds exhibited significant insecticidal activities against oriental armyworm, diamondback moth, beet armyworm, corn borer, and mosquito. Among them, trifluoroethoxyl-containing carbonyl thiourea <b>20a</b> showed best larvicidal activity against oriental armyworm, with LC₅₀ and LC₉₅ values of 0.1812 and 0.7767 mg/L, respectively. Meanwhile, <b>20c</b> and <b>20e</b> showed 86 and 57% death rates against diamondback moth at 0.005 mg/L, and the LC₅₀ values of the two compounds were 0.0017 and 0.0023 mg/L, respectively, which were lower than that of the control chlorantraniliprole. The relationship between structure and insecticidal activity was discussed, and the HF calculation results indicated that the carbonyl thiourea moiety plays an important role in the insecticidal activity. The present work demonstrated that the trifluoroethoxyl-containing carbonyl thioureas can be used as lead compounds for further development of novel insecticides

Research on Controllable Degradation of Novel Sulfonylurea Herbicides in Acidic and Alkaline Soils

The degradation issue of sulfonylurea (SU) has become one of the biggest challenges that hamper the development and application of this class of herbicides, especially in the alkaline soils of northern China. On the basis of the previous discovery that some substituents on the fifth position of the benzene ring in Chlorsulfuron could hasten its degradation rate, apparently in acidic soil, this work on Metsulfuron-methyl showed more convincing results. Two novel compounds (<b>I-1</b> and <b>I-2</b>) were designed and synthesized, and they still retained potent herbicidal activity in tests against both dicotyledons and monocotyledons. The half-lives of degradation (DT₅₀) assay revealed that <b>I-1</b> showed an accelerated degradation rate in acidic soil (pH 5.59). Moreover, we delighted to find that the degradation rate of <b>I-1</b> was 9–10-fold faster than that of Metsulfuron-methyl and Chlorsulfuron when in alkaline soil (pH 8.46), which has more practical value. This research suggests that a modified structure that has potent herbicidal activity as well as accelerated degradation rate could be realized and this approach may provide a way to improve the residue problem of SUs in farmlands with alkaline soil