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Hao Peng - One of the best experts on this subject based on the ideXlab platform.
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synthesis and herbicidal activities of potassium methyl 1 substituted phenoxyacetoxy Alkylphosphonate
Chemical Research in Chinese Universities, 2013Co-Authors: Tao Wang, Wei Wang, Hao PengAbstract:A series of potassium methyl 1-(substituted phenoxyacetoxy)Alkylphosphonates(9a–9o) was designed and synthesized. The results of preliminary bioassays indicate that most of the title compounds possess excellent pre-emergence and post-emergence herbicidal activities against Brassica napus, Amaranthus mangostanus, Medicago sativa, Echinochloa crusgalli, and Digitaria sanguinalis at a dosage of 1500 g/ha(1 ha=10000 m2). Especially, potassium methyl 1-(2,4-dichlorophenoxyacetoxy)-1-(4-methylphenyl)methylphosphonate(9g) and potassium methyl 1-(2,4-dichlorophenoxyacetoxy)-1-(furan-2-yl)methylphosphonate(9j) show the best herbicidal activity against five tested weeds with more than 85% inhibitory rate in pre-emergence.
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α substituted phenoxyacetoxy α heterocyclylmethylphosphonates synthesis herbicidal activity inhibition on pyruvate dehydrogenase complex pdhc and application as postemergent herbicide against broadleaf weeds
Journal of Agricultural and Food Chemistry, 2013Co-Authors: Hao Peng, Junlin Yuan, Ting Chen, Tao Wang, Chubei Wang, Xiaosong TanAbstract:Pyruvate dehydrogenase complex (PDHc) is the site of action of a new class of herbicides. On the basis of the previous work for O,O′-dimethyl α-(substituted-phenoxyacetoxy)Alkylphosphonates (I), fu...
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studies of o o dimethyl α 2 4 dichlorophenoxyacetoxy ethylphosphonate hw02 as a new herbicide 1 synthesis and herbicidal activity of hw02 and analogues as novel inhibitors of pyruvate dehydrogenase complex
Journal of Agricultural and Food Chemistry, 2011Co-Authors: Junlin Yuan, Hao Peng, Ting Chen, Ping Shen, Shuqing Wan, Hongliang TanAbstract:On the basis of the previous work for optimization of O,O-diethyl α-(substituted phenoxyacetoxy)Alkylphosphonates, further extensive synthetic modifications were made to the substituents in Alkylphosphonate and phenoxy moieties of the title compounds. New O,O-dimethyl α-(substituted phenoxyacetoxy)Alkylphosphonates were synthesized as potential inhibitors of pyruvate dehydorogenase complex (PDHc). Their herbicidal activity and efficacy in vitro against PDHc were examined. Some of these compounds exhibited significant herbicidal activity and were demonstrated to be effective inhibitors of PDHc from three different plants. The structure−activity relationships of these compounds including previously reported analogous compounds were studied by examining their herbicidal activities. Both inhibitory potency against PDHc and herbicidal activity of title compounds could be increased greatly by optimizing substituent groups of the title compounds. O,O-Dimethyl α-(2,4-dichlorophenoxyacetoxy)ethylphosphonate (I-5),...
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separation and aquatic toxicity of enantiomers of 1 substituted phenoxyacetoxy Alkylphosphonate herbicides
Chirality, 2008Co-Authors: Shanshan Zhou, Hao Peng, Xiaosong Tan, Meirong Zhao, Anping Zhang, Chunmian LinAbstract:A series of organophosphorous compounds (OPs), 1-(substituted phenoxyacetoxy)Alkylphosphonates containing a chiral carbon atom, show notable herbicidal activities. In this study, the enantioselective separation and biological toxicity of all these compounds were investigated. The enantioselective separation on the columns of Chiralpak AD, Chiralpak AS, Chiralcel OD, and Chiralcel OJ were compared under various chromatographic conditions. All the analytes investigated obtained baseline resolution (Rs > 1.5) on Chiralpak AD column, which showed best chiral separation capacity. Further investigation was carried out on Chiralpak AD to evaluate the influence of the mobile phase composition and column temperature. The effect of the structural features on discrimination was also examined. The resolved enantiomers were distinguished by their signs of circular dichroism. The acute aquatic toxicity of enantiomers and racemate to Daphnia magna (D. magna) were assessed. The in vivo assays showed that compound 3 was about 2-148.5 times more toxic than the other four analogues to D. magna. The racemates of compounds 3 and 5 showed intermediate toxicity compare to their enantiomers, while those of compounds 1, 2, and 4 showed synergistic or antagonistic effect. These results suggest that the biological toxicity of chiral OPs to nontarget organisms is enantioselective and therefore should be evaluated with their pure enantiomers. Chirality, 2008. © 2007 Wiley-Liss, Inc.
Mateusz Psurski - One of the best experts on this subject based on the ideXlab platform.
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convenient syntheses of novel 1 isothiocyano Alkylphosphonate diphenyl ester derivatives with potential biological activity
ChemInform, 2013Co-Authors: Mateusz Psurski, Marta Pigula, Jaroslaw Ciekot, Joanna Wietrzyk, Lukasz Winiarski, Jozef OleksyszynAbstract:A novel one-pot method is developed to synthesize isothiocyanates of type (IV) (10 examples), where the resulting primary adducts are cleaved at the carbamate moiety by acid.
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convenient syntheses of novel 1 isothiocyano Alkylphosphonate diphenyl ester derivatives with potential biological activity
Tetrahedron Letters, 2012Co-Authors: Mateusz Psurski, Marta Pigula, Jaroslaw Ciekot, łukasz Winiarski, Joanna Wietrzyk, Jozef OleksyszynAbstract:Herein, we describe a convenient method for the syntheses of novel 1-isothiocyano-Alkylphosphonate diaryl ester derivatives and their antiproliferative activity. The syntheses are based on dithiocarbamates obtained in situ with the use of carbon disulfide under basic conditions, and their desulfurization using several different reagents, of which hydrogen peroxide proved to be the most efficient. The compounds synthesized demonstrated high antiproliferative activity against several cancer cell lines in vitro, and also showed some activity as serine protease inhibitors.
Yuqi Feng - One of the best experts on this subject based on the ideXlab platform.
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combining poly methacrylic acid co ethylene glycol dimethacrylate monolith microextraction and octadecyl phosphonic acid modified zirconia coated cec with field enhanced sample injection for analysis of antidepressants in human plasma and urine
Electrophoresis, 2010Co-Authors: Jin Fan, Fang Wei, Mingming Zheng, Yuqi FengAbstract:A method based on poly (methacrylic acid-co-ethylene glycol dimethacrylate) monolith microextraction and octadecylphosphonic acid-modified zirconia-coated CEC followed by field-enhanced sample injection preconcentration technique was proposed for sensitive CE-UV analysis of six antidepressants (doxepin, clozapine, imipramine, paroxetine, fluoxetine and chlorimipramine) in human plasma and urine. A poly(methacrylic acid-co-ethylene glycol dimethacrylate) monolithic capillary column was introduced for the extraction of antidepressants from urine and plasma samples. The hydrophobic main chains and acidic pendant groups of the monolithic column make it a superior material for extraction of basic analytes from aqueous matrix. After extraction, the desorption solvent, which normally provided an excellent medium to ensure direct compatibility for field-enhanced sample injection in CE, was analyzed by CE directly. By the use of Alkylphosphonate-modified zirconia-coated CEC for separation of the basic compounds of antidepressants, high separation efficiency and resolution were achieved because that both hydrophobic interaction between analytes and Alkylphosphonate-modified zirconia coat and electrophoretic effect work on the separation of antidepressants. The best separation was achieved using a buffer composed of 0.3 M ammonium acetate (adjusted to pH 4.5 with 1 M acetic acid) and 35% ACN v/v, with a temperature and voltage of 20 degrees C and 20 kV, respectively. By applying both preconcentration procedures, LODs of 11.4-51.5 and 3.7-17.0 microg/L were achieved for the six antidepressants in human plasma and urine, respectively. Excellent method of reproducibility was found over a linear range of 50-5000 microg/L in plasma and urine sample.
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capillary electrochromatography with Alkylphosphonate modified magnesia zirconia as the chromatographic support material
Journal of Liquid Chromatography & Related Technologies, 2001Co-Authors: Dongsheng Xia, Yuqi FengAbstract:A capillary electrochromatography with a new packing material, Alkylphosphonate-modified magnesia-zirconia stationary phase (APMZ), was developed. The influence of some parameters such as pH, concentration of methanol and TRIS in the buffer on EOF, and chromatographic behavior of APMZ in CEC is investigated. It was found that, with a slight change in EOF over pH range from 4.5 to 9.3, the APMZ behaves as reserved-phase packing for polycyclic aromatic hydrocarbons (PAHs) and basic compounds. Furthermore, the ion-exchange interaction between APMZ and basic compounds at low pH was observed.
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retention behavior of basic compounds on Alkylphosphonate modified magnesia zirconia composite stationary phase in rphplc
Chromatographia, 2000Co-Authors: Yuqi Feng, Qinghe Zhang, Youjie ZhangAbstract:The chromatographic properties of an Alkylphosphonate-modified magnesia-zirconia composite stationary phase have been investigated by reversed-phase high-performance liquid chromatography with basic compounds as probes. The influence of organic modifier composition and mobile phase pH was studied. The new stationary phase, similar to a silica-based reversed-phase stationary phase, has hydrophobic properties, but greater pH stability. Use of the phase results in more symmetric peaks for basic compounds. A possible mechanism of retention of basic solutes on the new stationary phase is discussed. The chromatographic behavior of the basic solutes depends mainly on hydrophobic interactions between the solutes and the hydrophobic moiety of the stationary phase. Bronsted acidic and basic sites on the surface of the new stationary phase play an important role in the retention of ionized solutes by ion-exchange interaction. Promising separations of some basic compounds have been achieved by use of methanolic TRIS buffer, pH 10.0, as the mobile phase.
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preparation and characterization of Alkylphosphonate modified magnesia zirconia composite for reversed phase liquid chromatography
Analytical Sciences, 2000Co-Authors: Yuqi Feng, Qinghe Zhang, D A Shilu, Yan ZhangAbstract:A new material : magnesia-zirconia composite modified by an Alkylphosphonate can be used as a reversed-phase stationary phase for high-performance liquid chromatography. The new material was characterized by elemental analysis, FTIR and 13 C solid state NMR spectrometry. The pH stability of the new material was investigated using biphenyl and N,N'-dimethylaniline as probes with methanol-water (60:40, v/v) as a mobile phase, after the column was continuously purged with solutions at extreme pH 2 and pH 11. The chromatographic performance of the new material was studied by using polycyclic aromatic hydrocarbons (PAHs) and basic compounds as probes. The results indicate that the new material is of high pH stability and can be used for separation of PAHs and basic compounds.
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retention behavior of some polycyclic aromatic hydrocarbons on Alkylphosphonate modified magnesia zirconia composite stationary phase for reversed phase liquid chromatography
Chinese Journal of Chromatography, 2000Co-Authors: Yuqi Feng, Qinghe Zhang, Yan ZhangAbstract:An Alkylphosphonate modified magnesia zirconia composite stationary phase (PZMS) for reversed phase liquid chromatography was prepared. The reversed phase chromatographic performance of the new packing material was investigated with some polycyclic aromatic hydrocarbons (PAHs) as solutes. The effect of the methanol content in the mobile phase on the retention of PAHs was examined. The logarithmic capacity factor of PAHs was decreased linearly with increasing volume percent of the methanol in the mobile phase, which is similar to that observed on Zorbax ODS. The capacity factor of PAHs on the new stationary phase was also correlated to their partition coefficient between n octanol and water (log P ). A good linear relationship between them was obtained. These results show that the new material can behave as a reversed phase packing. The separations of phenanthrene and anthracene, and terphenyl isomers were investigated on the new stationary phase and the Zorbax ODS, respectively. The retention of the solutes on the Zorbax ODS is greater than that on the new stationary phase, but the separation selectivity of the solutes on the new stationary phase is better than that on the Zorbax ODS. The better separation selectivity on the new stationary phase may be contributed from the Lewis acid base interaction between the solutes and the residual Lewis acid sites on the stationary phase.
Junlin Yuan - One of the best experts on this subject based on the ideXlab platform.
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α substituted phenoxyacetoxy α heterocyclylmethylphosphonates synthesis herbicidal activity inhibition on pyruvate dehydrogenase complex pdhc and application as postemergent herbicide against broadleaf weeds
Journal of Agricultural and Food Chemistry, 2013Co-Authors: Hao Peng, Junlin Yuan, Ting Chen, Tao Wang, Chubei Wang, Xiaosong TanAbstract:Pyruvate dehydrogenase complex (PDHc) is the site of action of a new class of herbicides. On the basis of the previous work for O,O′-dimethyl α-(substituted-phenoxyacetoxy)Alkylphosphonates (I), fu...
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studies of o o dimethyl α 2 4 dichlorophenoxyacetoxy ethylphosphonate hw02 as a new herbicide 1 synthesis and herbicidal activity of hw02 and analogues as novel inhibitors of pyruvate dehydrogenase complex
Journal of Agricultural and Food Chemistry, 2011Co-Authors: Junlin Yuan, Hao Peng, Ting Chen, Ping Shen, Shuqing Wan, Hongliang TanAbstract:On the basis of the previous work for optimization of O,O-diethyl α-(substituted phenoxyacetoxy)Alkylphosphonates, further extensive synthetic modifications were made to the substituents in Alkylphosphonate and phenoxy moieties of the title compounds. New O,O-dimethyl α-(substituted phenoxyacetoxy)Alkylphosphonates were synthesized as potential inhibitors of pyruvate dehydorogenase complex (PDHc). Their herbicidal activity and efficacy in vitro against PDHc were examined. Some of these compounds exhibited significant herbicidal activity and were demonstrated to be effective inhibitors of PDHc from three different plants. The structure−activity relationships of these compounds including previously reported analogous compounds were studied by examining their herbicidal activities. Both inhibitory potency against PDHc and herbicidal activity of title compounds could be increased greatly by optimizing substituent groups of the title compounds. O,O-Dimethyl α-(2,4-dichlorophenoxyacetoxy)ethylphosphonate (I-5),...
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synthesis and herbicidal activities of methyl 1 2 4 dichlorophenoxyacetoxy Alkylphosphonate monosalts
Journal of Organometallic Chemistry, 2005Co-Authors: Tao Wang, Junlin YuanAbstract:Abstract A series of 1-(2,4-dichlorophenoxyacetoxy)alkylphosphonic acid dimethyl esters 5 and its corresponding phosphonate monosalts 6 were synthesized as potential herbicide. The phosphonate monosalts can be prepared from 1-(2,4-dichlorophenoxyacetoxy)alkylphosphonic acid dimethyl esters 5 , which were synthesized by the condensation of O , O -dimethyl-1-hydroxyAlkylphosphonates with dichlorophenoxyacetic chloride. This method provides a simple and efficient procedure for the synthesis of phosphonate derivatives containing sensitive groups to acid, base or water such as carboxylate ester bond; and the herbicidal activity of title compounds was evaluated in a set of experiments in greenhouse. Most of the compounds exhibited notable herbicidal activity.
Xiaosong Tan - One of the best experts on this subject based on the ideXlab platform.
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α substituted phenoxyacetoxy α heterocyclylmethylphosphonates synthesis herbicidal activity inhibition on pyruvate dehydrogenase complex pdhc and application as postemergent herbicide against broadleaf weeds
Journal of Agricultural and Food Chemistry, 2013Co-Authors: Hao Peng, Junlin Yuan, Ting Chen, Tao Wang, Chubei Wang, Xiaosong TanAbstract:Pyruvate dehydrogenase complex (PDHc) is the site of action of a new class of herbicides. On the basis of the previous work for O,O′-dimethyl α-(substituted-phenoxyacetoxy)Alkylphosphonates (I), fu...
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separation and aquatic toxicity of enantiomers of 1 substituted phenoxyacetoxy Alkylphosphonate herbicides
Chirality, 2008Co-Authors: Shanshan Zhou, Hao Peng, Xiaosong Tan, Meirong Zhao, Anping Zhang, Chunmian LinAbstract:A series of organophosphorous compounds (OPs), 1-(substituted phenoxyacetoxy)Alkylphosphonates containing a chiral carbon atom, show notable herbicidal activities. In this study, the enantioselective separation and biological toxicity of all these compounds were investigated. The enantioselective separation on the columns of Chiralpak AD, Chiralpak AS, Chiralcel OD, and Chiralcel OJ were compared under various chromatographic conditions. All the analytes investigated obtained baseline resolution (Rs > 1.5) on Chiralpak AD column, which showed best chiral separation capacity. Further investigation was carried out on Chiralpak AD to evaluate the influence of the mobile phase composition and column temperature. The effect of the structural features on discrimination was also examined. The resolved enantiomers were distinguished by their signs of circular dichroism. The acute aquatic toxicity of enantiomers and racemate to Daphnia magna (D. magna) were assessed. The in vivo assays showed that compound 3 was about 2-148.5 times more toxic than the other four analogues to D. magna. The racemates of compounds 3 and 5 showed intermediate toxicity compare to their enantiomers, while those of compounds 1, 2, and 4 showed synergistic or antagonistic effect. These results suggest that the biological toxicity of chiral OPs to nontarget organisms is enantioselective and therefore should be evaluated with their pure enantiomers. Chirality, 2008. © 2007 Wiley-Liss, Inc.