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 biological evaluation of novel <i>N</i>-pyridylpyrazolecarboxamides containing benzothiazole

<p></p> <p>A series of novel <i>N</i>-pyridylpyrazolecarboxamides containing benzothiazole were designed and synthesized. The target compounds were identified by ¹H NMR,¹³C-NMR, IR, high-resolution mass spectrum (HRMS) and elemental analysis. The bioactivities of the new compounds against oriental army worm (<i>Mythimnaseparata</i>) and diamond back moth <i>(Plutellaxylostella</i>) were evaluated. The results of bioassays indicated that some of the compounds showed good activitiesat the tested concentrations. Compound <b>Ij</b> showed 100% larvicidal activities against <i>Plutellaxylostella</i> at 2.5 mg/L, while the activity of <b>Ij</b> against <i>Mythimnaseparata</i> was 100% at 10 mg/L.</p

Synthesis, Crystal Structure, in Vitro Acetohydroxyacid Synthase Inhibition, in Vivo Herbicidal Activity, and 3D-QSAR of New Asymmetric Aryl Disulfides

Acetohydroxyacid synthase (AHAS; EC 2.2.1.6) is an important bioactive target for the design of environmentally benign herbicides. On the basis of previous virtual screening, 50 asymmetric aryl disulfides containing [1,2,4]­triazole groups were synthesized and characterized by ¹H NMR, HRMS, and crystal structure. Compounds <b>I-a</b>, <b>I-b</b>, and <b>I-p</b> show <i>K</i>_i values of 1.70, 4.69, and 5.57 μM, respectively, for wild type Arabidopsis thaliana AHAS (<i>At</i>AHAS) and low resistance against mutant type <i>At</i>AHAS W574L. At 100 mg L^–1 concentration, compounds <b>I-a</b>, <b>II-a</b>, and <b>II-b</b> exhibit 86.6, 81.7, and 87.5% in vivo rape root growth inhibition. CoMFA steric and electrostatic contour maps were established, and a possible binding mode was suggested from molecular docking, which provide valuable information to understand the key structural features of these disulfide compounds. To the authors' knowledge, this is the first comprehensive case suggesting that asymmetric aryl disulfides are novel AHAS inhibitors

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

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, 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

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 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

Novel Ultrasound-Promoted Parallel Synthesis of Trifluoroatrolactamide Library via a One-Pot Passerini/Hydrolysis Reaction Sequence and Their Fungicidal Activities

An ultrasound-promoted one-pot Passerini/hydrolysis reaction sequence has been developed for the synthesis of trifluoroatrolactamide derivatives using a diverse range of trifluoroacetophenones and isonitriles in acetic acid. Parallel synthesis in a centrifuge tube using a noncontact ultrasonic cell crusher was used in this study as an efficient method for the rapid generation of combinatorial trifluoroatrolactamide libraries, and subsequent biochemical evaluation of the resulting compounds indicated that they possessed excellent broad-spectrum fungicidal activities. <i>N</i>-(4-chlorophenyl)-2-(4-ethylphenyl)-3,3,3-trifluoro-2-hydroxypropanamide and <i>N</i>-(4-chlorophenyl)-3,3,3-trifluoro-2-hydroxy-2-(4-methoxyphenyl)­propanamide, in particular, showed significant fungicidal activities against all of the fungal species tested in the current study

Concise Synthesis of Natural Phenylphenalenone Phytoalexins and a Regioisomer

Concise total syntheses of the natural phytoalexins 2-hydroxy-8-(4-hydroxyphenyl)­phenalen-1-one (<b>1</b>), 2-hydroxy-8-(3,4-dihydroxyphenyl)­phenalen-1-one (<b>2</b>), and hydroxyanigorufone (<b>4</b>), together with regioisomer <b>3</b> are accomplished in 11 or 12 steps. The synthetic strategy features a Friedel–Crafts acylation to construct the 1<i>H</i>-phenalen-1-one tricyclic core followed by a Suzuki cross-coupling to obtain the target compounds