Synthesis and fungicidal activity of aryl(arylamino)methylphosphonic acids

<p>A series of aryl(arylamino)methylphosphonic acids were synthesized based on the previous work for the modification of alkylphosphonates. As key intermediates, α-aminophosphonates were synthesized with high yield by a three-component Kabachnik–Fields reaction under solvent-free conditions. The compounds were identified and characterized by infrared, ¹H NMR, ¹³C NMR, mass spectrum, and elemental analyses. Their fungicidal activities against typical fungi occurring in the Chinese agro-ecosystems were evaluated. The results of preliminary bioassays showed that some of the title compounds exhibited moderate fungicidal activities against tomato late blight and cucumber fusarium wilt. For example, compound <b>3b</b> showed 78% inhibitory activity against tomato late blight, and compound <b>3h</b> possessed 86% inhibitory activity against cucumber fusarium wilt.</p

3D-Qsar on 1-Substituted Phenoxyacetoxyalkylphosphonates and Phosphinates Using CoMFA and CoMSIA

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

Functional Group Effect on Char Formation, Flame Retardancy and Mechanical Properties of Phosphonate–Triazine-based Compound as Flame Retardant in Epoxy Resin

A series of novel flame-retardant thermosets were prepared by melt blending of phosphonate–triazine-based compound TNTP, triazine-based compound TN, and phosphonate-based compound TP, respectively. The curing systems were consisted of diglycidyl ether of bisphenol A (DGEBA) and 4,4′-diamino-diphenyl sulfone (DDS). The thermal behaviors and flame retardancy of these flame-retardant thermosets were investigated in terms of thermogravimetric analysis (TGA), limiting oxygen index (LOI), vertical burning test (UL-94) and cone calorimeter tests. TGA results showed that the char formation of flame-retardant thermosets could be significantly improved due to the presence of phosphonate moiety rather than triazine unit. It was found that the excellent flame retardant effect of TNTP was not contributed by either single group of phosphonate or triazine. An obvious synergic-effect on flame retardant produced by a combination of phosphonate and triazine moiety. The LOI value of TNTP-3/DGEBA/DDS could achieve 32.4% and reach UL-94 V-0 rating, while that of TN-3/DGEBA/DDS was 29.0% and failed in UL-94 test, and TP-3/DGEBA/DDS with a LOI value of 31.8% just reach UL-94 V-1 rating. Moreover, cone calorimeter test revealed that the incorporation of TNTP to epoxy thermoset with 1.5 wt % phosphorus content could result in a decrease of peak heat release rate (PHRR), total heat release (THR), average mass loss rate (AMLR), total smoke release (TSR), average CO yield (ACOY), and average CO₂ yield (ACO₂Y) compared with DGEBA/DDS control. The results from TGA data, scanning electronic microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) indicated TNTP modified thermosets had a comprehensive flame retardant mechanism, including the gas phase, condensed phase and phosphorus–nitrogen synergism mechanism. Furthermore, the mechanical properties of all the thermosets were also investigated by Izod impact strength and flexural property tests

Synthesis and Herbicidal Activities of Sodium Methyl(<i>α</i>-(Substituted Phenoxyacetoxy)Alkyl)Phosphinates

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

Synthesis and Biological Activities of <i>O</i>,<i>O</i>-Dialkyl 1-((4,6-Dichloropyrimidin-2-yl)Carbamyloxy) Alkylphosphonates

<div><p></p><p>A series of new 1-((4,6-dichloropyrimidin-2-yl)carbamyloxy) alkylphosphonates were designed and synthesized. The structures of all the title compounds were confirmed by IR, ¹H-NMR, ³¹P-NMR and elemental analysis. The results of the bioassay showed that all of title compounds exhibited weak herbicidal activities against monocotyledons and <a href="http://dicotyledon" target="_blank">dicotyledon</a>s; however, some of them showed potential plant growth regulatory activities.</p></div

A Well-Defined Cyclotriphosphazene-Based Epoxy Monomer and Its Application as A Novel Epoxy Resin: Synthesis, Curing Behaviors, and Flame Retardancy

<div><p></p><p>A novel cyclotriphosphazene-based epoxy monomer, hexa-[4-(glycidyloxycarbonyl) phenoxy]cyclotriphosphazene (HGCP), was synthesized via a four-step synthetic route, and fully characterized by ¹H, ¹³C, and ³¹P NMR spectroscopy, high-resolution mass spectrometry, and elemental analysis. Thermosetting systems based on HGCP with three curing agents, for example, 4,4′-diaminodiphenylsulfone (DDS), 4,4′-diaminodiphenylmethane (DDM), and dicyandiamide (DICY), were used for making a comparison of their thermal curing behaviors. The curing behaviors were measured by differential scanning calorimetry. Moreover, flame retardancy of HGCP thermosetting systems was estimated by Limiting Oxygen Index (LOI) and Vertical Burning Test (UL-94). The resulting HGCP thermosetting systems exhibited better flame retardancy than the common epoxy resins diglycidyl ether of bisphenol A (DGEBA) and the regular brominated bisphenol A epoxy resin (TBBA) cured by DDS, respectively. When HGCP was cured by DDS, its thermosetting system gave the most char residues, met the UL-94 V-0 classification, and had a limiting oxygen index value greater than 35.</p> </div

Convenient approach to synthesize tertiary α-hydroxy cyclic phosphonates catalyzed by potassium carbonate under solvent-free conditions

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

Modeling of SlSCPx-2 protein.

<p>(A) Dynamics curve. Trajectories were recorded every 1ps during the entire MD simulation process. Each point represents a 3D-structure of SlSCPx-2/SCPI1. The final optimal structure SlSCPx-2/SCPI1 was an averaged conformation modeling derived from the trajectories of the converged 18900–20900 ps. (B) The final optimal structure of the SlSCPx-2/SCPI1 complex in a ribbon view. The α–helixes are shown in blue and the β–sheets are shown in pink. Selected amino acid residues that directly interact with the bound ligand (black colored sticks; F53, F89, T128, and Q131) and indirectly contact with the ligand (dark green colored stick; W66 and F110) were used for point mutation. The AeSCPI-1 is highlighted as stick model colored cyan. (C) The Ramachandran plot of the SlSCPx-2/SCPI1 complex. The orange color represents those residues in the most favored regions; The dark yellow represents those residues in the additionally allowed regions; The light yellow represents those residues in generously allowed regions; The white represents those residues in disallowed regions.</p

Bioassays of the selected compounds for inhibition of growth of <i>S. litura</i> larvae.

<p>Newly hatching larvae were treated with the individual compounds at different concentrations and the body weight of the larvae was recorded at the indicated time points. At 13 days post egg hatching, most of the larvae were at 5^th instar stage.</p

Hit compounds selected from SPECS with high score values that potentially bind with SlSCPx-2 based on its modeled 3D-structure.

<p>These compounds were selected for the <i>in vitro</i> competitive binding assay and bioassay.</p