- New insight into the mechanism of methyl transfer during the biosynthesis of fosfomycin
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Hydroxyethylphosphonate is a required intermediate in fosfomycin biosynthesis. The Royal Society of Chemistry.
- Woodyer, Ryan D.,Li, Gongyong,Zhao, Huimin,Van Der Donk, Wilfred A.
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- A novel biosurfactant, 2-acyloxyethylphosphonate, isolated from waterblooms of Aphanizomenon flos-aquae
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A novel biosurfactant, 2-acyloxyethylphosphonate, was isolated from waterblooms of Aphanizomenon flos-aquae. Its structure was elucidated by chemical degradation and HRFABMS, GC/EI-MS and 1D- and 2D-NMR spectral analyses. The surfactant contained one mole of 2-hydroxyethylphosphonate and one mole of fatty acid, with hexadecanoic acid accounting for 84.1% of the total fatty acid content. The structure was confirmed by synthesis of 2-oleoyloxyethylphosphonate from ethylene oxide, phosphorus acid and oleic acid chloride. Considering the isolated surfactant molecule as hexadecanoyloxyethylphosphonic acid (mw. 364), the critical micelle concentration (CMC) was about 22 mM.
- Kaya, Kunimitsu,Morrison, Louise F.,Codd, Geoffrey A.,Metcalf, James S.,Sano, Tomoharu,Takagi, Hiroo,Kubo, Takuya
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- Biosynthesis of the Fungal Organophosphonate Fosfonochlorin Involves an Iron(II) and 2-(Oxo)glutarate Dependent Oxacyclase
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The fungal metabolite Fosfonochlorin features a chloroacetyl moiety that is unusual within known phosphonate natural product biochemistry. Putative biosynthetic genes encoding Fosfonochlorin in Fusarium and Talaromyces spp. were investigated through reactions of encoded enzymes with synthetic substrates and isotope labelling studies. We show that the early biosynthetic steps for Fosfonochlorin involve the reduction of phosphonoacetaldehyde to form 2-hydroxyethylphosphonic acid, followed by oxidative intramolecular cyclization of the resulting alcohol to form (S)-epoxyethylphosphonic acid. The latter reaction is catalyzed by FfnD, a rare example of a non-heme iron/2-(oxo)glutarate dependent oxacyclase. In contrast, FfnD behaves as a more typical oxygenase with ethylphosphonic acid, producing (S)-1-hydroxyethylphosphonic acid. FfnD thus represents a new example of a ferryl generating enzyme that can suppress the typical oxygen rebound reaction that follows abstraction of a substrate hydrogen by a ferryl oxygen, thereby directing the substrate radical towards a fate other than hydroxylation.
- Gama, Simanga R.,Stankovic, Toda,Hupp, Kendall,Al Hejami, Ahmed,McClean, Mimi,Evans, Alysa,Beauchemin, Diane,Hammerschmidt, Friedrich,Pallitsch, Katharina,Zechel, David L.
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- Characterization of the transient oxaphosphetane BChE inhibitor formed from spontaneously activated ethephon
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The major plant growth regulator ethephon degrades to ethylene and phosphate in aqueous solutions and plants and is spontaneously activated to a butyrylcholinesterase (BChE) inhibitor in alkaline solutions and animal tissues. In the present 31P NMR kinetic study of the reactions of ethephon in pH 7.4 carbonate buffer, we observed a transient peak at 28.11 ppm. The time course for the appearance and disappearance of this peak matches the activation/degradation kinetic profile of the BChE inhibitor, and the chemical shift supports the proposed 2-oxo-2-hydroxy-1,2-oxaphosphetane structure.
- Lantz, Stephen R.,Casida, John E.
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- Double-Layered Plasmonic–Magnetic Vesicles by Self-Assembly of Janus Amphiphilic Gold–Iron(II,III) Oxide Nanoparticles
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Janus nanoparticles (JNPs) offer unique features, including the precisely controlled distribution of compositions, surface charges, dipole moments, modular and combined functionalities, which enable excellent applications that are unavailable to their symmetrical counterparts. Assemblies of NPs exhibit coupled optical, electronic and magnetic properties that are different from single NPs. Herein, we report a new class of double-layered plasmonic–magnetic vesicle assembled from Janus amphiphilic Au-Fe3O4 NPs grafted with polymer brushes of different hydrophilicity on Au and Fe3O4 surfaces separately. Like liposomes, the vesicle shell is composed of two layers of Au-Fe3O4 NPs in opposite direction, and the orientation of Au or Fe3O4 in the shell can be well controlled by exploiting the amphiphilic property of the two types of polymers.
- Song, Jibin,Wu, Binghui,Zhou, Zijian,Zhu, Guizhi,Liu, Yijing,Yang, Zhen,Lin, Lisen,Yu, Guocan,Zhang, Fuwu,Zhang, Guofeng,Duan, Hongwei,Stucky, Galen D.,Chen, Xiaoyuan
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- Pharmacophore elucidation of phosphoiodyn A - Potent and selective peroxisome proliferator-activated receptor β/δ agonists with neuroprotective activity
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We report the pharmacophore of the peroxisome proliferator-activated receptor δ (PPARδ) agonist natural product phosphoiodyn A is the phosphonate core. Synthesis of simplified phosphonate esters 13 and 15 provide structurally novel, highly selective and potent PPARδ agonists (EC50 = 78 and 112 nM, respectively). Further, both compounds demonstrate significant neuroprotective activity in an in vitro cellular model indicating that phosphonates may be an effective novel scaffold for the design of therapeutics for the treatment of neurodegenerative disorders.
- Kinarivala, Nihar,Suh, Ji Ho,Botros, Mina,Webb, Paul,Trippier, Paul C.
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supporting information
p. 1889 - 1893
(2016/04/05)
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- PREPARATION OF A HYDROXYALKYL PHOSPHONIC ACID
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The present invention is a process for converting a phosphonate to a hydroxyalkyl phosphonic acid comprising the step of contacting together water, the phosphonate, and a sulfonated or phosphonated heterogeneous catalyst under conditions sufficient to convert at least 50% of the phosphonate to the hydroxyalkyl phosphonic acid. The process of the present invention provides a way of preparing hydroxyalkyl phosphonic acids safely and economically, without corrosive effects.
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Paragraph 0009
(2016/01/01)
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- Comparative study on hydrolysis of 2-chloroethylphosphonic acid dialkylesters
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2-Chloroethylphosphonic acid dialkylesters (bis-(2-chloroethyl), dimethyl, diethyl, dipropyl, dibutyl and dipentylesters) were hydrolyzed in order to obtain 2-chloroethylphosphonic acid, used as a plant growth regulator. Experiments were made in neutral or acid conditions, in order to find optimal conditions for esters hydrolysis. The obtained 2-chloroethylphosphonic acid was tested, regarding its biological activity, on melon, cucumber, blackcurrant and bilberry.
- Ilia, Gheorghe,Cǎprita, Adrian,Iliescu, Smaranda,Popa, Adriana,Pascariu, Aurelia,Bora, Alina,Dehelean, Gheorghe
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p. 501 - 506
(2007/10/03)
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- A bimetallic system for the catalytic hydroxylation of remote primary C- H bonds in functionalized organics using dioxygen
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In a mixture of trifluoroacetic acid and water, the combination of metallic palladium and copper chloride catalyzes the hydroxylation of remote primary C-H bonds of a variety of acids, alcohols, and aliphatic halides, in the presence of carbon monoxide and dioxygen. Experiments suggest that the principal role of metallic palladium is to generate hydrogen peroxide in situ and that the species responsible for the remote hydroxylation of the substrate by hydrogen peroxide is copper chloride. The unusual preference for the catalytic hydroxylation of primary C-H bonds was also found in an experiment involving competition between ethane and either cumene or p- isopropylbenzoic acid: even though the solution concentration of ethane was significantly lower than the competing substrate, the vast majority of the oxidation product (ethanol) was derived from ethane. In the reactions studied, acetic acid and formic acid were formed through C-C cleavage steps. An examination of the site of C-C cleavage in propionic acid indicated that both C-C bonds were being broken.
- Shen, Chengyu,Garcia-Zayas, Eduardo A.,Sen, Ayusman
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p. 4029 - 4031
(2007/10/03)
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- MECHANISM OF THE PHOSPHORYLATION REACTION OF 2-HALOALKYLPHOSPHONIC ACIDS
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2-Haloalkylphosphonic acids require aqueous solutions of suitable pH to react as phosphorylating agents.Reaction rates are slow at pH1, moderate at pK12 (monoanion) and fast at pH>pK2 (dianion).The end products in water are phosphoric acid (major) and 2-hydroxyalkyl- and vinylphosphonic acids (minor).The dianinon is stable in non-aqueous solutions.The order of reactivity is bromo>chloro>>fluoro.Dehydrohalogenation is the major patway with mono- and diesters.In contrast, 2-chloroethylphosphonothioic acid dianion is stable even at pH 13.These findings are consistent with a mechanism involving a bimolecular process rather than an SN1 pathway via a metaphosphate intermediate.
- Segall, Yoffi,Toia, Robert F.,Casida, John E.
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p. 191 - 194
(2007/10/02)
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- ZUR CHEMIE DER 2-HYDROXYETHANPHOSPHONSEAURE
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Acidolysis and hydrolysis of 2-acetoxyethanephosphonic acid dimethyl ester 2 and 2-hydroxyethanephosphonic acid dimethyl ester 3 and their derivatives leads to 2-hydroxyethanephosphonic acid 1.With the aid of 31P-NMR-spectroscopy, the courses of the reactions are investigated and the by-products are identified and determined quantitatively.
- Kleiner, Hanss-Jerg,Schumann, Christian
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p. 363 - 370
(2007/10/02)
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