Artículos de revistas: "Phosphite"

1

Inoue, Hidenari, Hiromi Akahori, Yuri Ohno, Katsuo Nakazawa, Yoshimune Nonomura, Naoki Yoshioka, Gernot Heckmann, and Ekkehard Fluck. "Axial Coordination of Phosphine or Phosphite to Iron(III) Chlorophyll a." Zeitschrift für Naturforschung B 50, no. 8 (August 1, 1995): 1222–28. http://dx.doi.org/10.1515/znb-1995-0817.

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The adduct formation of iron(III) chlorophyll a with phosphines or phosphites has been studied by spectroscopic methods. The red-shift in the Soret and Q bands caused by the axial coordination of phosphine or phosphite to iron(III) chlorophyll a is an evidence for the autoreduction of the central iron(III) ion. The 31P{1H} NMR spectrum of bis-adducts measured in the presence of excess phosphine or phosphite ligands gave a single peak in the down field range compared to that of the corresponding free ligand. The ESR and X-ray photoelectron spectra have revealed that the central iron atom of the bis-adduct of iron chlorophyll a with phosphines or phosphites is divalent and in the low-spin state. The axial coordination of phosphine or phosphite influences the electronic configuration of the central iron atom and the macrocyclic chlorine ligand to induce the autoreduction of the central iron(III) ion.

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2

Villa, Eric, Justin Cross, and Thomas Albrecht-Schmitt. "New Uranyl Open Framework and Sheet Compounds Formed via In-Situ Protonation of Piperazine by Phosphorous Acid." Minerals 8, no. 11 (November 1, 2018): 497. http://dx.doi.org/10.3390/min8110497.

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Two new uranyl compounds were hydrothermally synthesized employing piperazine as an organic templating agent. The piperazine was protonated in-situ by phosphorous acid, forming the piperazinium dication featured in these compounds. The two new structures presented here are a uranyl phosphite 2D sheet and a 3D uranyl mixed phosphite–phosphate network with cation occupied channels. Both included strong hydrogen bonding from the piperazinium cation to the uranyl phosphite or mixed phosphite–phosphate network. These two structures can be reliably formed through careful control of pH of the starting solution and the reaction duration. The piperazinium uranyl phosphite compound was the latest in a family of uranyl phosphites, and demonstrates the structural versatility of this combination. The mixed phosphite–phosphate compound builds on hydrothermal redox chemistry, illustrating the variety of compounds that can be isolated by exploiting in-situ redox processes to elucidate new uranium structure types.

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3

McDonald, Allison E., Julie O. Niere, and William C. Plaxton. "Phosphite disrupts the acclimation of Saccharomyces cerevisiae to phosphate starvation." Canadian Journal of Microbiology 47, no. 11 (November 1, 2001): 969–78. http://dx.doi.org/10.1139/w01-099.

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The influence of phosphite (H2PO3) on the response of Saccharomyces cerevisiae to orthophosphate (HPO42; Pi) starvation was assessed. Phosphate-repressible acid phosphatase (rAPase) derepression and cell development were abolished when phosphate-sufficient (+Pi) yeast were subcultured into phosphate-deficient (Pi) media containing 0.1 mM phosphite. By contrast, treatment with 0.1 mM phosphite exerted no influence on rAPase activity or growth of +Pi cells. 31P NMR spectroscopy revealed that phosphite is assimilated and concentrated by yeast cultured with 0.1 mM phosphite, and that the levels of sugar phosphates, pyrophosphate, and particularly polyphosphate were significantly reduced in the phosphite-treated Pi cells. Examination of phosphite's effects on two PHO regulon mutants that constitutively express rAPase indicated that (i) a potential target for phosphite's action in Pi yeast is Pho84 (plasmalemma high-affinity Pi transporter and component of a putative phosphate sensor-complex), and that (ii) an additional mechanism exists to control rAPase expression that is independent of Pho85 (cyclin-dependent protein kinase). Marked accumulation of polyphosphate in the Δpho85 mutant suggested that Pho85 contributes to the control of polyphosphate metabolism. Results are consistent with the hypothesis that phosphite obstructs the signaling pathway by which S. cerevisiae perceives and responds to phosphate deprivation at the molecular level.Key words: Saccharomyces cerevisiae, phosphite, phosphate starvation, PHO regulon.

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4

Förster, H., J. E. Adaskaveg, D. H. Kim, and M. E. Stanghellini. "Effect of Phosphite on Tomato and Pepper Plants and on Susceptibility of Pepper to Phytophthora Root and Crown Rot in Hydroponic Culture." Plant Disease 82, no. 10 (October 1998): 1165–70. http://dx.doi.org/10.1094/pdis.1998.82.10.1165.

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Tomato and pepper plants were grown hydroponically in a greenhouse using phosphate or technical and commercial formulations of phosphite as sources of phosphorus nutrition to determine the effects on plant development and susceptibility to Phytophthora root and crown rot. Phosphite-treated tomato and pepper plants were deficient of phosphate and developed phosphorus-deficiency symptoms. Growth of plants (leaf area and leaf, stem, and root dry weights) that were fertilized with phosphite was significantly (P < 0.05) reduced compared with phosphate-fertilized plants. In Phytophthora capsici–inoculated pepper plants, incidence of Phytophthora crown rot was significantly reduced in phosphite-treated plants compared with no phosphorus or phosphate-treated plants. Incidence of crown rot in pepper plants treated with 1 mM phosphate plus 0.3 mM phosphite was intermediate between plants treated with only phosphite (1 mM or 0.1 mM) and plants treated with phosphate (1 mM).

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5

Ávila, Fabricio William, Valdemar Faquin, Douglas Ramos Guelfi Silva, Carla Elisa Alves Bastos, Nilma Portela Oliveira, and Danilo Araújo Soares. "Phosphite as phosphorus source to grain yield of common bean plants grown in soils under low or adequate phosphate availability." Ciência e Agrotecnologia 36, no. 6 (December 2012): 639–48. http://dx.doi.org/10.1590/s1413-70542012000600006.

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The effects of foliar and soil applied phosphite on grain yield in common bean (Phaseolus vulgaris L.) grown in a weathered soil under low and adequate phosphate availability were evaluated. In the first experiment, treatments were composed of a 2 x 7 + 2 factorial scheme, with 2 soil P levels supplied as phosphate (40 e 200 mg P dm-3 soil), 7 soil P levels supplied as phosphite (0-100 mg P dm-3 soil), and 2 additional treatments (without P supply in soil, and all P supplied as phosphite). In the second experiment, treatments were composed of a 2 x 3 x 2 factorial scheme, with 2 soil phosphate levels (40 e 200 mg P dm-3 soil), combined with 3 nutrient sources applied via foliar sprays (potassium phosphite, potassium phosphate, and potassium chloride as a control), and 2 foliar application numbers (single and two application). Additional treatments showed that phosphite is not P source for common bean nutrition. Phosphite supply in soil increased the P content in shoot (at full physiological maturity stage) and grains, but at the same time considerably decreased grain yield, regardless of the soil phosphate availability. Foliar sprays of phosphite decreased grain yield in plants grown under low soil phosphate availability, but no effect was observed in plants grown under adequate soil phosphate availability. In general, foliar sprays of phosphate did not satisfactorily improve grain yield of the common bean plants grown under low soil phosphate availability.

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6

Deliy, Irina, Ivan Shamanaev, Pavel Aleksandrov, Evgeny Gerasimov, Vera Pakharukova, Evgeny Kodenev, Ilya Yakovlev, Olga Lapina, and Galina Bukhtiyarova. "Support Effect on the Performance of Ni2P Catalysts in the Hydrodeoxygenation of Methyl Palmitate." Catalysts 8, no. 11 (November 3, 2018): 515. http://dx.doi.org/10.3390/catal8110515.

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The effect of support nature, SiO2 and γ-Al2O3, on physicochemical and catalytic properties of nickel phosphide catalysts in methyl palmitate hydrodeoxygenation (HDO) has been considered. Firstly, alumina-supported nickel phosphide catalysts prepared by temperature-programmed reduction method starting from different precursors (phosphate–Ni(NO3)2 and (NH4)2HPO4 or phosphite–Ni(OH)2 and H3PO3) were compared using elemental analysis, N2 physisorption, H2-TPR, XRD, TEM, NH3-TPD, 27Al and 31P MAS NMR techniques and catalytic experiments. The mixture of nickel phosphide phases was produced from phosphate precursor on alumina while using of phosphite precursor provides Ni2P formation with the higher activity in methyl palmitate HDO. Besides, the comparative study of the performances of Ni2P/SiO2 and Ni2P/Al2O3 catalysts demonstrates the apparent superiority of alumina-supported Ni2P in the methyl palmitate hydrodeoxygenation. Considering the tentative scheme of methyl palmitate transformation, we proposed that cooperation of Ni2P and acid sites on the surface of alumina provides the enhanced activity of alumina-supported Ni2P through the acceleration of acid-catalysed hydrolysis.

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7

Oka, Yuji, Nadia Tkachi, and Mishael Mor. "Phosphite Inhibits Development of the Nematodes Heterodera avenae and Meloidogyne marylandi in Cereals." Phytopathology® 97, no. 4 (April 2007): 396–404. http://dx.doi.org/10.1094/phyto-97-4-0396.

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Phosphonic acid (H3PO3) solutions were applied to wheat or to bristle oat as soil drenches before inoculation with juveniles of the sedentary, endoparasitic nematodes Heterodera avenae or Meloidogyne marylandi. All the solutions, which were pH adjusted and added at levels as low as 0.63 mg of phosphite (HPO32-) per plant, reduced the numbers of H. avenae females and M. marylandi egg masses. Phosphate (PO43-), applied as potassium phosphate at the same concentrations, did not reduce the number of female nematodes on the wheat. Addition of phosphate to the phosphite solutions did not change the inhibitory effect of phosphite on H. avenae, but it reduced phosphite's effect on M. marylandi. Phosphite also reduced the number of H. avenae females when applied as many as 20 days after addition of nematodes. The phosphite treatment did not prevent M. marylandi juveniles from penetrating wheat roots or inducing giant cells. However, phosphite inhibited giant cell development: 14 days after inoculation, the giant cells in the phosphite-treated wheat were almost completely vacuolated, whereas those in untreated wheat contained dense cytoplasm.

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8

Liu, Kunlu, Min Wang, Yubo Zhou, Hongxiang Wang, Yudong Liu, Lu Han, and Weiwei Han. "Exploration of the cofactor specificity of wild-type phosphite dehydrogenase and its mutant using molecular dynamics simulations." RSC Advances 11, no. 24 (2021): 14527–33. http://dx.doi.org/10.1039/d1ra00221j.

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9

Guidone, Stefano, Fady Nahra, Alexandra M. Z. Slawin, and Catherine S. J. Cazin. "Ruthenium indenylidene “1st generation” olefin metathesis catalysts containing triisopropyl phosphite." Beilstein Journal of Organic Chemistry 11 (September 1, 2015): 1520–27. http://dx.doi.org/10.3762/bjoc.11.166.

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The reaction of triisopropyl phosphite with phosphine-based indenylidene pre-catalysts affords “1st generation” cis-complexes. These have been used in olefin metathesis reactions. The cis-Ru species exhibit noticeable differences with the trans-Ru parent complexes in terms of structure, thermal stability and reactivity. Experimental data underline the importance of synergistic effects between phosphites and L-type ligands.

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10

Araujo, Josinaldo Lopes, Fabrício William de Ávila, and Valdemar Faquin. "Phosphite and phosphate in the accumulation and translocation of nutrients in common bean1." Pesquisa Agropecuária Tropical 46, no. 4 (December 2016): 357–66. http://dx.doi.org/10.1590/1983-40632016v4640810.

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ABSTRACT Although used as an additional nutritional source of phosphorus in agriculture, little is known about the effects of phosphites on plants. In order to evaluate the influence of phosphite and phosphate on the accumulation and translocation of phosphorus and cationic nutrients, in common bean, three experiments were conducted. In the first experiment, five concentrations (0.5 mg L-1, 10 mg L-1, 20 mg L-1, 30 mg L-1 and 60 mg L-1) were studied in a nutrient solution combined with two forms of phosphorus [phosphate (Pi) and phosphite (Phi)]. In the second one, five Phi/Pi ratios were tested (0/100, 25/75, 50/50, 75/25 and 100/0). In the third experiment, two phosphate levels (1.5 mg L-1 = limiting and 20 mg L-1 = adequate phosphorus) and three treatments related to foliar fertilization (KH2PO3, KH2PO4 and KCl solutions) were combined in the nutrient solution. Phosphite via roots caused a decrease in the accumulation of phosphorus and cationic nutrients, under phosphate deficiency. P-Phi decreased the Zn/P ratio more than P-Pi, increased the translocation of P and decreased the translocation of Fe. The foliar supply of P-Phi did not affect the phosphorus nutrition of bean plants or the translocation of nutrients, but decreased the accumulation of K, Ca, Mg, Fe and Mn. Foliar P-Pi, at an adequate P supply in the nutrient solution, increased the accumulation of this nutrient.

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11

Metcalf, William W., and Ralph S. Wolfe. "Molecular Genetic Analysis of Phosphite and Hypophosphite Oxidation by Pseudomonas stutzeriWM88." Journal of Bacteriology 180, no. 21 (November 1, 1998): 5547–58. http://dx.doi.org/10.1128/jb.180.21.5547-5558.1998.

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ABSTRACT The first molecular and genetic characterization of a biochemical pathway for oxidation of the reduced phosphorus (P) compounds phosphite and hypophosphite is reported. The pathway was identified inPseudomonas stutzeri WM88, which was chosen for detailed studies from a group of organisms isolated based on their ability to oxidize hypophosphite (+1 valence) and phosphite (+3 valence) to phosphate (+5 valence). The genes required for oxidation of both compounds by P. stutzeri WM88 were cloned on a single ca. 30-kbp DNA fragment by screening for expression in Escherichia coli and Pseudomonas aeruginosa. Two lines of evidence suggest that hypophosphite is oxidized to phosphate via a phosphite intermediate. First, plasmid subclones that conferred oxidation of phosphite, but not hypophosphite, upon heterologous hosts were readily obtained. All plasmid subclones that failed to confer phosphite oxidation also failed to confer hypophosphite oxidation. No subclones that conferred only hypophosphite expression were obtained. Second, various deletion derivatives of the cloned genes were made in vitro and recombined onto the chromosome of P. stutzeriWM88. Two phenotypes were displayed by individual mutants. Mutants with the region encoding phosphite oxidation deleted (based upon the subcloning results) lost the ability to oxidize either phosphite or hypophosphite. Mutants with the region encoding hypophosphite oxidation deleted lost only the ability to oxidize hypophosphite. The phenotypes displayed by these mutants also demonstrate that the cloned genes are responsible for the P oxidation phenotypes displayed by the originalP. stutzeri WM88 isolate. The DNA sequences of the minimal regions implicated in oxidation of each compound were determined. The region required for oxidation of phosphite to phosphate putatively encodes a binding-protein-dependent phosphite transporter, an NAD+-dependent phosphite dehydrogenase, and a transcriptional activator of the lysR family. The region required for oxidation of hypophosphite to phosphite putatively encodes a binding-protein-dependent hypophosphite transporter and an α-ketoglutarate-dependent hypophosphite dioxygenase. The finding of genes dedicated to oxidation of reduced P compounds provides further evidence that a redox cycle for P may be important in the metabolism of this essential, and often growth-limiting, nutrient.

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12

Szirtes, L., A. M. Szeleczky, and E. Kuzmann. "Zirconium phosphate–phosphite containing silica." Solid State Ionics 97, no. 1-4 (May 1, 1997): 223–26. http://dx.doi.org/10.1016/s0167-2738(97)00045-3.

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13

Kasuga, Takao, Katherine J. Hayden, Catherine A. Eyre, Peter J. P. Croucher, Shannon Schechter, Jessica W. Wright, and Matteo Garbelotto. "Innate Resistance and Phosphite Treatment Affect Both the Pathogen’s and Host’s Transcriptomes in the Tanoak-Phytophthora ramorum Pathosystem." Journal of Fungi 7, no. 3 (March 9, 2021): 198. http://dx.doi.org/10.3390/jof7030198.

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Phosphites have been used to control Sudden Oak Death; however, their precise mode of action is not fully understood. To study the mechanism of action of phosphites, we conducted an inoculation experiment on two open-pollinated tanoak families, previously found to be partially resistant. Stems of treatment group individuals were sprayed with phosphite, and seven days later, distal leaves were inoculated with the Sudden Oak Death pathogen Phytophthora ramorum. Leaves from treated and untreated control plants were harvested before and seven days after inoculation, and transcriptomes of both host and pathogen were analyzed. We found that tanoak families differed in the presence of innate resistance (resistance displayed by untreated tanoak) and in the response to phosphite treatment. A set of expressed genes associated with innate resistance was found to overlap with an expressed gene set for phosphite-induced resistance. This observation may indicate that phosphite treatment increases the resistance of susceptible host plants. In addition, genes of the pathogen involved in detoxification were upregulated in phosphite-treated plants compared to phosphite-untreated plants. In summary, our RNA-Seq analysis supports a two-fold mode of action of phosphites, including a direct toxic effect on P. ramorum and an indirect enhancement of resistance in the tanoak host.

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14

Formisano, Luigi, Begoña Miras-Moreno, Michele Ciriello, Christophe El-Nakhel, Giandomenico Corrado, Luigi Lucini, Giuseppe Colla, and Youssef Rouphael. "Trichoderma and Phosphite Elicited Distinctive Secondary Metabolite Signatures in Zucchini Squash Plants." Agronomy 11, no. 6 (June 14, 2021): 1205. http://dx.doi.org/10.3390/agronomy11061205.

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Plant biostimulants are “green” solutions to improve crop production. Trichoderma spp. and phosphites, ordinarily used as biocontrol agents, can trigger phytostimulation, also promoting endogenous mechanisms involved in plant growth and development. The present study aimed at assessing the efficacy of a phosphite-based formulation (Phosphit-One) and Trichoderma harzianum-T22 on the morpho-physiological response and modulation of the metabolomics profile in zucchini squash plants (Cucurbita pepo L.) cultivated in controlled growth conditions (Fitotron®). The highest values of fresh biomass production (390.9 g plant−1) and root dry weight (5.6 g plant−1) were obtained for Trichoderma-treated plants. This last treatment resulted in an improved physiological performance (SPAD index, CO2 assimilation rate, and Fv/Fm ratio) measured 30 days after transplanting. Both Trichoderma and phosphite treatments induced a broad metabolic reprogramming in leaves, evident also for the phosphite treatment that did not result in a growth promotion. The microbial and the non-microbial treatments showed distinctive signatures in secondary metabolism yet, common responses could be also highlighted. For instance, both Trichoderma and phosphite triggered ROS-mediated signaling processes, together with the accumulation of phenylpropanoids, glucosinolates, and phytoalexins. Furthermore, a significant alteration of phytohormones was observed, with terpenoid gibberellins and brassinosteroids showing the largest differences. The metabolomic signatures induced by Trichoderma and phosphite in zucchini squash provided molecular insights into the processes underlying elicitation of plant defense due to biostimulation. Interestingly, the modulation of plant secondary metabolism by both treatments did not impair plant growth.

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15

Jackson, WR, CG Lovel, P. Perlmutter, and AJ Smallridge. "The Stereochemistry of Organometallic Compounds. XXXI. Hydrocyanation of Alkynols." Australian Journal of Chemistry 41, no. 7 (1988): 1099. http://dx.doi.org/10.1071/ch9881099.

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The regioselectivity of hydrocyanation of a range of alkynols using nickel-based catalyst systems involving either triphenyl phosphite or α,α′-bis(diphenylphosphino)-o-xylene (phmep) has been investigated. The regioselectivity of the hydrocyanations involving the phosphine catalyst reflected dominant steric effects whereas results from the phosphite catalyst system showed some evidence for chelation control. Yields of nitriles from reactions based on the phosphite system were variable, whereas moderate to good yields of distilled products could be obtained consistently by using the phosphine -based system. An explanation for this variation in yield is proposed.

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16

Motevalli, Somayeh, and Jeffrey Johnson. "Phosphite-Mediated Reductive Cross-Coupling of Isatins and Nitrostyrenes." Synthesis 49, no. 12 (May 2, 2017): 2663–76. http://dx.doi.org/10.1055/s-0036-1588170.

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A new reductive coupling reaction between N-alkylisatins, dimethyl phosphite, and nitrostyrenes has been developed. The reaction relies on Pudovik addition, subsequent phosphonate–phosphate rearrangement, and Michael-type addition of a transient carbanion on the indolinone with β-nitrostyrenes. This protocol introduces a convenient and versatile method for the construction of polyfunctionalized tertiary phosphates under mild conditions. Chiral general bases catalyze the title reaction with promising levels of enantioselectivity.

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17

Tkaczyk, Miłosz, Katarzyna A. Kubiak, Jacek Sawicki, Justyna A. Nowakowska, and Tomasz Oszako. "The use of phosphates in forestry." Forest Research Papers 77, no. 1 (March 1, 2016): 76–81. http://dx.doi.org/10.1515/frp-2016-0009.

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Abstract Phosphite preparations are now an important alternative in plant protection against new, invasive pathogens of the genus Phytophthora and/or Pythium. It is crucial to intervene when alien, invasive oomycetes are carried to plantations or forest stands and attack fine roots via zoospores. The aim of this paper was to demonstrate the possibility of phosphite application to induce resistance to tree pathogens. Phosphate-based fertilizers have been used successfully in nurseries, where application is relatively easy by means of foliar sprays. the traditional fungicides, which are effective in combating fungi, however, fail to control oomycetes. Instead, they mask the disease, which, in turn, causes serious damage to seedlings after they have been planted in a suitable environment. Moreover, the number of effective fungicides available for forest plant protection has continued to decrease in the last decade. The effectiveness of the chemicals is reduced due to their frequent use and their similarity in terms of the active compound or the mechanism of action. Given the low diversity of active compounds, it is necessary to monitor the development of resistance of pathogens to fungicides by means of molecular biology (sequencing and quantitative PCR). Minimising the undesired side effects of chemicals on both, mycorrhizal fungi and pathogens can be achieved by strict adherence to rigorous security measures and, where possible, frequently changing the active compounds to alternatives such as phosphites. The significance of phosphate and phosphite uptake by trees is still a matter of debate, especially under field conditions. Nevertheless, phosphites are environmentally friendly compounds, which constitute an alternative or complement to the traditional chemicals (in accordance with the Directive on Integrated Plant management).

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18

Jiao, Yunzhe, William W. Brennessel, and William D. Jones. "A tris(pyrazolyl)borate rhodium phosphite complex that undergoes an Arbusov-like rearrangement." Acta Crystallographica Section C Crystal Structure Communications 69, no. 9 (August 3, 2013): 939–42. http://dx.doi.org/10.1107/s0108270113015953.

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Tp′Rh[P(OMe)3](Me)H, loses methane in pentane solution containing CH2F2to give the scorpionate complex bis(μ-dimethyl phosphito)-κ2P:O;κ2O:P-bis{methyl[tris(3,5-dimethyl-1H-pyrazol-1-yl-κN2)borato]rhodium(III)}, [Rh2(CH3)2(C2H6O3P)2(C15H22BN6)2], in which the phosphine O—Me bond is cleaved. The product is dimeric and resembles the Arbusov-type rearrangement product known to form from trimethyl phosphite.

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19

Isama, K., T. Kawakami, and Y. Ikarashi. "Cytotoxicity of phosphite and phosphate triesters." Toxicology Letters 238, no. 2 (October 2015): S365. http://dx.doi.org/10.1016/j.toxlet.2015.08.1044.

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20

Banko, T. J., and C. X. Hong. "Evaluation of Nutrient Phosphite for the Control of Phytophthora Shoot Blight on Annual Vinca." Journal of Environmental Horticulture 22, no. 1 (March 1, 2004): 41–44. http://dx.doi.org/10.24266/0738-2898-22.1.41.

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Abstract Annual vinca (Catharanthus roseus) were grown in containers in a greenhouse and irrigated with a complete nutrient solution containing phosphite (0, 0.1, 0.3 mM), phosphate (0, 0.3, 0.5 mM), or combinations of these two compounds as a source of phosphorus. After 2 weeks, the plants were sprayed with a Phytophthora nicotianae zoospore inoculum to evaluate the potential for phosphite to protect annual vinca from Phytophthora shoot blight. To determine the extent and duration of protection from shoot blight provided by phosphite foliar applications, the plants were treated with phosphite foliar sprays (0.5 mM) at various intervals, and then inoculated. Application of phosphite to the soil/roots provided no protection from Phytophthora shoot blight. However, foliar applications of phosphite at a concentration of 0.5 mM at three to six day intervals gave protection similar to foliar applications of Aliette fungicide at 3 g/liter (2.5 lb/100 gal) applied at 14 day intervals.

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21

Tarasenko, Karen V., Igor I. Gerus, Valery P. Kukhar та Vitaly V. Polovinko. "Reactions of β-aminovinyl bromodifluoromethyl ketones with alkyl phosphites: Perkow versus Arbuzov". Collection of Czechoslovak Chemical Communications 74, № 2 (2009): 335–46. http://dx.doi.org/10.1135/cccc2008095.

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New bromodifluoromethyl enaminones 1a–1f and γ-bromo-β-morpholinopropenyl fluoromethyl ketones 2a, 2b were synthesized. N-Substituted bromodifluoromethyl enaminones 1a–1d do not react with triethyl or diethyl phosphites, whereas N-acylated enaminones 1e, 1f gave difluorodienyl phosphates 4a, 4b as Perkow rearrangement products. Fluoroketone 2a reacts easily with triethyl phosphite according to the Arbuzov protocol and a perspective building block – trifluoromethyl-containing phosphonate 7a is formed.

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22

Abdreimova, R. R., F. Kh Faizova, and A. A. Karimova. "Copper (II) Catalyzed Oxidative Alkoxylation of White Phosphorus. Communication 2." Eurasian Chemico-Technological Journal 12, no. 3,4 (May 19, 2010): 267. http://dx.doi.org/10.18321/ectj54.

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White phosphorus has been catalytically oxidized by oxygen in alcoholic solutions of copper (II) acetylacetonate, halides or carboxylates to yield dialkyl phosphites and trialkyl phosphates under mild reaction conditions. Trialkyl phosphite has been observed as unstable organophosphorus intermediate, which is being converted into the main reaction products. In the case of methanolic solutions, the derivatives of two step acidolysis of dimethyl phosphite, monomethyl phosphite and phosphorous acid, have been additionally detected among the reaction products. The influence of the copper (II) catalysts on the kinetics of accumulation and transmutation of organophosphorus products has been explored. It has been found that the Cu(II) compounds take a role of catalysts-electron-carriers from white phosphorus to oxygen. The indispensable molar ratio between catalyst and white phosphorus and the order of catalytic activity for the copper (II) compounds have been established. The major steps of the catalytic reaction including (i) the coordination of white phosphorus and alcohol to metal ion, (ii) the redox decomposition of this intermediate complex accompanied by reducing elimination of elementary copper and formation of organophosphorus product and (iii) the oxidation of the reduced form of catalyst by oxygen have been<br />also suggested.

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23

Inoue, Hidenari, Masahiro Sasagawa, and Ekkehard Fluck. "31P-NMR-und 57Fe-Mößbauer-spektroskopische Untersuchungen an Pentacyano(phosphan oder phosphit)ferraten(II) / 31P NMR and 57Fe Mössbauer Spectroscopic Studies on Pentacyano(phosphane or phosphite)ferrates(II)." Zeitschrift für Naturforschung B 40, no. 1 (January 1, 1985): 22–25. http://dx.doi.org/10.1515/znb-1985-0107.

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The 31P{1H}NMR spectra for a series of pentacyanoferrates(II) of the type Na3[Fe(CN)5L] (L = phosphine or phosphite) have been measured. A low field chemical shift range of 48.1-88.7 ppm for phosphine complexes and of 32.5-48.4 ppm for phosphite complexes is observed when one compares free vs. coordinated ligands. The correlation between chemical shifts in the 31P NMR spectra and isomeric shifts in the Mössbauer spectra is investigated and discussed

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24

Lemmen, Peter, Rosmarie Karl, Ivar Ugi, Neil Balgobin та Jyoti Chattopadhyaya. "Bausteine für Oligonucleotid-Synthesen mit einheitlich fragmentierbaren β-halogenierten Schutzgruppen /Building Blocks for Oligonucleotide Syntheses with Uniformly Fragmentable β-Halogenated Protecting Groups". Zeitschrift für Naturforschung C 42, № 4 (1 квітня 1987): 442–45. http://dx.doi.org/10.1515/znc-1987-0419.

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Abstract 5′-Dimethoxytrityl-3′-phosphite amides of deoxynucleosides are synthesized. Phosphite/phosphate is protected by the 2,2,2-trichloro-1,1-dimethyl-ethyl (TCB) group, heterocyclic bases by the 2,2,2-trichloro-2,2-dimethyl-ethoxycarbonyl (TCBOC) group. Deoxyguanosine is also block ed by 6-O-trichloroethyl thus avoiding the difficulties observed with monoprotected guanine residues.

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25

Gull, Maheen, Tian Feng, and Matthew A. Pasek. "Results of an Eight-Year Extraction of Phosphorus Minerals within the Seymchan Meteorite." Life 12, no. 10 (October 12, 2022): 1591. http://dx.doi.org/10.3390/life12101591.

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In-fall of extraterrestrial material including meteorites and interstellar dust particles during the late heavy bombardment are known to have brought substantial amounts of reduced oxidation-state phosphorus to the early Earth in the form of siderophilic minerals, e.g., schreibersite ((FeNi)3P). In this report, we present results on the reaction of meteoritic phosphide minerals in the Seymchan meteorite in ultrapure water for 8 years. The ions produced during schreibersite corrosion (phosphite, hypophosphate, pyrophosphate, and phosphate) are stable and persistent in aqueous solution over this timescale. These results were also compared with the short-term corrosion reactions of the meteoritic mineral schreibersite’s synthetic analog Fe3P in aqueous and non-aqueous solutions (ultrapure water and formamide). This finding suggests that the reduced-oxidation-state phosphorus (P) compounds including phosphite could be ubiquitous and stable on the early Earth over a long span of time and such compounds could be readily available on the early Earth.

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26

Mihichuk, Lynn, Monica Pizzey, Beverly Robertson, and Richard Barton. "The synthesis and seven-coordinate structure of (CH3)2AsC(CF3=C(CF3)As(CH3)2W(CO)Br2[P(OCH3)3]2." Canadian Journal of Chemistry 64, no. 5 (May 1, 1986): 991–95. http://dx.doi.org/10.1139/v86-166.

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(L–L)W(CO)4 (L–L = (CH3AsC(CF3)=C(CF3)As(CH3)2) is oxidized by Br2 to yield the seven-coordinate complex (L–L)W(CO)3Br2, which reacts with monodentate phosphines or phosphites to form (L–L)W(CO)Br2P2 (P = phosphine or phosphite). Crystals of (L–L)W(CO)Br2[P(OCH3)3]2 are monoclinic, space group P21/c, a = 19.110(5), b = 9.208(3), c = 17.845(6) Å, β = 108.93(2)° at 21 °C with Z = 4. The structure was solved from a Patterson map and refined by least squares to a conventional R value of 0.092 using 2330 independent reflections. The crystal structure indicated the tungsten atom to be seven-coordinate with the geometry most closely approximated by a capped trigonal prismatic environment, the capping group being a bromine atom (W—Br, 2.686(5) Å). The capped face consists of the remaining bromine atom (W—Br, 2.695(5) Å), a phosphorus atom (W—P, 2.465(9) Å), and the two arsenic atoms from the bidentate ligand (W—As, 2.619(3) and 2.526(4) Å). The W—As bond trans to a phosphite is significantly longer (by 0.093 Å) than the W—As bond trans to a bromine. The 1H nmr data indicate that the complex is stereochemically rigid at 25 °C and nonrigid at higher temperatures; however, the data at 25 °C are not consistent with the configuration found in the crystal.

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27

Cutolo, Edoardo, Matteo Tosoni, Simone Barera, Luis Herrera-Estrella, Luca Dall’Osto, and Roberto Bassi. "A Phosphite Dehydrogenase Variant with Promiscuous Access to Nicotinamide Cofactor Pools Sustains Fast Phosphite-Dependent Growth of Transplastomic Chlamydomonas reinhardtii." Plants 9, no. 4 (April 8, 2020): 473. http://dx.doi.org/10.3390/plants9040473.

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Heterologous expression of the NAD+-dependent phosphite dehydrogenase (PTXD) bacterial enzyme from Pseudomonas stutzerii enables selective growth of transgenic organisms by using phosphite as sole phosphorous source. Combining phosphite fertilization with nuclear expression of the ptxD transgene was shown to be an alternative to herbicides in controlling weeds and contamination of algal cultures. Chloroplast expression of ptxD in Chlamydomonas reinhardtii was proposed as an environmentally friendly alternative to antibiotic resistance genes for plastid transformation. However, PTXD activity in the chloroplast is low, possibly due to the low NAD+/NADP+ ratio, limiting the efficiency of phosphite assimilation. We addressed the intrinsic constraints of the PTXD activity in the chloroplast and improved its catalytic efficiency in vivo via rational mutagenesis of key residues involved in cofactor binding. Transplastomic lines carrying a mutagenized PTXD version promiscuously used NADP+ and NAD+ for converting phosphite into phosphate and grew faster compared to those expressing the wild type protein. The modified PTXD enzyme also enabled faster and reproducible selection of transplastomic colonies by directly plating on phosphite-containing medium. These results allow using phosphite as selective agent for chloroplast transformation and for controlling biological contaminants when expressing heterologous proteins in algal chloroplasts, without compromising on culture performance.

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28

Zhuang, Quan, and Jack M. Miller. "Sol-gel synthesis of ternary phosphate-ZrO2-SiO2 catalysts for alcohol dehydration." Canadian Journal of Chemistry 79, no. 8 (August 1, 2001): 1224–28. http://dx.doi.org/10.1139/v01-108.

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PhosphateZrO2Si2O catalysts were synthesized by sol-gel method using tributyl phosphite, zirconium propoxide, and tetraethyl orthosilicate as precursors. They were characterized by N2 adsorption, 31P CP MAS NMR, and DRIFTS. At lower P content, monomeric phosphates were formed on the surface of the catalysts, which were mainly responsible for the isopropanol dehydration activity. At higher P content, polyphosphates were formed, and thus, the dehydration activity decreased. An optimum P content for dehydration activity was found to be at 10 mol%.Key words: sol-gel synthesis, ternary oxides, phosphate, acid catalyst, alcohol dehydration, 31P CP MAS NMR, N2 adsorption, DRIFTS.

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29

Prévôté, Delphine, Anne-Marie Caminade, and Jean Pierre Majoral. "Phosphate-, Phosphite-, Ylide-, and Phosphonate-Terminated Dendrimers." Journal of Organic Chemistry 62, no. 14 (July 1997): 4834–41. http://dx.doi.org/10.1021/jo9701750.

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30

Lee, Jin-Kyun, Rachel M. Williamson, Andrew B. Holmes, Edward J. Bush, and Ian F. McConvey. "A Study of the Heck Reaction in Non-Polar Hydrocarbon Solvents and in Supercritical Carbon Dioxide." Australian Journal of Chemistry 60, no. 8 (2007): 566. http://dx.doi.org/10.1071/ch07160.

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The effects of electronic and steric properties of phosphorus ligands on Heck reactions in supercritical CO2 and non-polar hydrocarbon solvents were studied. In Heck reactions between iodobenzene and butyl acrylate, higher yields were obtained with less electron-rich phosphine ligands. This trend was also observed with the electron-poor triphenyl phosphite. A range of sterically demanding phosphites were then investigated. Biphenyl-containing phosphites 8 and 13 were found to be highly effective. In the Heck reaction between the less-reactive bromobenzene and butyl acrylate, the bulky, electron-rich tri-tert-butylphosphine ligand produced the best yield. These results emphasize the importance of both electronic and steric properties of phosphorus ligands in the Heck reaction in non-polar solvents.

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31

Mihichuk, Lynn M., Carolyn L. Giesinger, Beverly E. Robertson, and Richard J. Barton. "Seven coordination. 1. Synthesis, structure, and fluxionality of(CH3)2AsC(CF3)=C(CF3)As(CH3)2W(CO)2I2P(OCH3)3." Canadian Journal of Chemistry 65, no. 11 (November 1, 1987): 2634–38. http://dx.doi.org/10.1139/v87-435.

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(L—L)W(CO)4 (L—L = (CH3)2AsC(CF3)=C(CF3)As(CH3)2) is oxidized by I2 to yield the seven-coordinate complex (L—L)W(CO)3I2 which reacts with monodentate phosphines or phosphites to form (L—L)W(CO)2I2P (P = phosphine or phosphite). Crystals of (L—L)W(CO)2I2P(OCH3)3 are monoclinic, space group P21/c, a = 15.711(3), b = 13.134(2), c = 13.800(3) Å, β = 111.81(2)° with Z = 4. The structure was solved from a Patterson map and anisotropically refined by least squares to a conventional R value of 0.039 using 3737 independent reflections. The crystal structure showed the tungsten atom to be seven-coordinate with a geometry most closely approximated by a capped octahedral environment, the capping group being a carbonyl moiety ([W—C] = 1.95 (1) Å). The capped face consists of the carbon atom ([W—C] = 1.98(1) Å) of the remaining carbonyl, an arsenic atom ([W—As] = 2.556(1) Å), and the phosphorus atom ([W—P] = 2.466(3) Å). The W—As bond trans to a phosphite group is longer (by 0.050(2) Å) than the W—As bond trans to an iodine atom. 1H nmr data indicate the complex to be fluxional at 298 K and rigid at lower temperatures, the data at lower temperatures being consistent with the configuration found in the crystal. The nmr data at lower temperatures suggest two exchange processes are occurring; one which averages two sets of As—CH3 groups and another process which averages all four As—CH3 groups.

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32

Kleman, P., P. Barbaro, and A. Pizzano. "Chiral Rh phosphine–phosphite catalysts immobilized on ionic resins for the enantioselective hydrogenation of olefins in water." Green Chemistry 17, no. 7 (2015): 3826–36. http://dx.doi.org/10.1039/c5gc00485c.

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33

Navarro Cerrillo, R. Mª, L. Gallo Ibáñez, Mª E. Sánchez Hernández, P. Fernández Rebollo, and A. Trapero Casas. "Effect of phosphoric fertilization on the resistance of holm oak and cork oak to Phytophthora cinnamomi Rands." Forest Systems 13, no. 3 (December 1, 2004): 550–58. http://dx.doi.org/10.5424/srf/2004133-00853.

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The oomycete Phytophthora cinnamomi Rands is the mean responsible for oak decline in southern Spain. This paper investigates the relationship between phosphoric fertilization of Quercus ilex and Q. suber seedlings and resistance to the disease caused by Phytophthora cinnamomi. The study was conducted on holm oak and cork oak seedlings previously submitted to a phosphoric fertilization programme involving four different treatments, namely: Phosphate-A (3 mg P2O5 seedling), Phosphate-B (6 mg P2O5 seedling), Phosphite (0.15 mg de P2O5 seedling) and No Fertilization. Tests were conducted in greenhouse over a period of 7 months and a number of treatments to plants inoculated with Phytophthora cinnamomi Rands. were applied, assessing the changes in their morphological (viz. height, root and collar diameter, and secondary root biomass) and physiological characteristics (viz. leaf nutrient contents). Based on the results, phosphate failed to improve plant resistance to P. cinnamomi; by contrast, phosphite successfully avoided infection by this pathogen. In fact, the phosphitetreated plants exhibited a morphological and physiological status similar to or even better than that of the non-inoculated controls. The protective effect of phosphite against P. cinnamomi can be achieved by applying it during seedling cultivation in nurseries.

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34

Kampmann, Sven S., Nikki Y. T. Man, Allan J. McKinley, George A. Koutsantonis, and Scott G. Stewart. "Exploring the Catalytic Reactivity of Nickel Phosphine–Phosphite Complexes." Australian Journal of Chemistry 68, no. 12 (2015): 1842. http://dx.doi.org/10.1071/ch15459.

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In this study, we present an investigation into various nickel phosphite and phosphite–phosphine complexes for use in the Mizoroki–Heck and Suzuki–Miyaura cross-coupling reactions and the ammonia arylation reaction. In these coupling reactions, it was discovered that the Ni[P(OEt)3]4, (dppf)Ni[P(OPh)3]2, and (binap)Ni[P(OPh)3]2 catalysts were the most effective. In addition, an optimisation process for these catalytic systems as well as functional group compatibility are discussed.

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35

Bishimbayeva, G. K., A. M. Nalibayeva, S. A. Saidullayeva, A. K. Zhangabayeva, A. Bold, D. S. Zhumabayeva, Y. N. Abdikalykov, and E. N. Panova. "EXTRACTION PROPERTIES OF SYNTHESIZED FLUORINATED ORGANOPHOSPHORUS COMPOUNDS." RASAYAN Journal of Chemistry 16, no. 01 (2023): 440–46. http://dx.doi.org/10.31788/rjc.2023.1618246.

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This work presents the results of studies of extraction properties in relation to the uranium of bis(2,2,2- trifluoroethyl)diallylamido phosphite, bis(2,2,2-trifluoroethyl)dimethylamido phosphite, and bis(N,Ndialamido)isopropyl phosphite synthesized by us earlier. Tests were carried out in a factory laboratory, as the initial solutions used nitrate solution prepared from uranium oxide (CU = 10.30 g/dm3 , CHNO3 = 56.40 g/dm3 ) and uranium sulfate solution prepared from the chemical concentrate of natural uranium and deoxidized with sulfuric acid (CU = 10.60 g/dm3 , CH2SO4 = 25.10 g/dm3 ). It was proved that the synthesized acyclic amido phosphites can effectively extract uranium from these technological solutions with a proper selection of technological parameters, and the degree of uranium extraction may vary from 34.43 to 95.94%.

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36

Schreiner, R. Paul. "Foliar Sprays Containing Phosphorus (P) Have Minimal Impact on ‘Pinot noir’ Growth and P Status, Mycorrhizal Colonization, and Fruit Quality." HortScience 45, no. 5 (May 2010): 815–21. http://dx.doi.org/10.21273/hortsci.45.5.815.

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Grapevines grown in low-phosphorus (P) soils typical of western Oregon vineyards may benefit from additional P applied to the canopy using foliar sprays. Alternatively, vines may be negatively affected by foliar P sprays because lower root colonization by arbuscular mycorrhizal fungi (AMF) could reduce uptake of other nutrients or increase vine water stress. The impact of foliar P sprays on vine growth, vine nutrient and water status, AMF colonization, and fruit yield and quality was studied in two ‘Pinot noir’ vineyards with a history of low vine P status over 3 years. Three foliar spray treatments [phosphite, phosphate, water (control)] were applied to vines three times each season using a standard air-blast sprayer at a commercial vineyard. Two foliar spray treatments (phosphite, water) were applied using a hand sprayer at a smaller research vineyard. Phosphite sprays increased leaf blade and petiole P concentrations and reduced arbuscular colonization of roots at the research vineyard, but neither phosphate nor phosphite significantly affected these variables at the commercial vineyard. Foliar P sprays had no effect on vine growth, vine water relations (leaf water potential and stomatal conductance), yield, or fruit quality attributes at either site. These results indicate that there is little benefit to spraying the canopy of grapevines with P, even in vineyards with low P status.

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37

Abdreimova, R. R., F. Kh Faizova, and A. A. Karimova. "Copper (II) Mediated Oxidative Alkoxylation of White Phosphorus. Communication 1." Eurasian Chemico-Technological Journal 12, no. 3,4 (May 19, 2010): 259. http://dx.doi.org/10.18321/ectj53.

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White phosphorus has been oxidized by copper (II) acetylacetonate, halides or carboxylates in aliphatic alcohols to yield dialkyl phosphates and trialkyl phosphates under inert atmosphere and mild reaction conditions. Trialkyl phosphite has been observed as unstable organophosphorus intermediate, which is being converted into the main reaction products. In the case of methanolic solutions, the derivatives of two step acidolysis of dimethyl phosphite, monomethyl phosphite and phosphorous acid, have been additionally detected among the reaction products. The influence of the copper (II) oxidants on the kinetics of accumulation and transmutation of organophosphorus products has been explored. The order of oxidative ability of the copper (II) compounds has been established. The major steps of the reaction including (i) the coordination of white phosphorus and alcohol to metal ion and (ii) the redox decomposition of this intermediate complex accompanied by reducing elimination of elementary copper and formation of organophosphorus product have been also suggested.

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38

Guo, Shengmei, Hu Cai, Wenjie Yan, Hongbo Zhou, Haoyuan Li, Huimin Hu, and Ying Yu. "NiCl2 as a Cheap and Efficient Precatalyst for the Coupling of Aryl Fluorosulfonate and Phosphite/Phosphine Oxide." Synlett 32, no. 14 (June 8, 2021): 1453–56. http://dx.doi.org/10.1055/a-1524-4912.

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AbstractHerein, NiCl2 is employed as a cheap precatalyst in the formation of C(sp2)–P bond via cross-coupling reaction of phenol derivatives and phosphine oxides/phosphites. This catalytic system allows a variety of phenols with diverse functional groups to transform into phosphates with good yields. No additional additive is used in this reaction.

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39

Grzebisz, Witold, Szymon Łączny, Witold Szczepaniak, and Jarosław Potarzycki. "Inorganic Fungicides (Phosphites) Instead of Organic Fungicides in Winter Wheat—Consequences for Nitrogen Fertilizer Productivity." Agronomy 13, no. 3 (February 22, 2023): 627. http://dx.doi.org/10.3390/agronomy13030627.

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Substitution of organic with inorganic fungicides (phosphites, Phi) does not change the efficiency of fertilizer nitrogen (Nf) in winter wheat. This hypothesis was tested in the 2016/2017 and 2017/2018 growing seasons. A two-factorial experiment with three phosphite variants (Cu–Phi, Mg–Phi, and Cu/Mg) and six plant protection methods (fungicides + Phi ⟶ reduced fungicide frequency + phosphite ⟶ phosphite). Grain yield decreased with increasing frequency of phosphites instead of fungicides. The decrease in yields was 3.6 t ha−1 in the favorable 2016/2017 and 1.1 t ha−1 in the dry 2017/2018. The primary reason for yield decrease in a given growing season was increased wheat infestation by pathogens. The direct cause was disturbances in the nitrogen status of wheat after flowering on treatments with a predominance of phosphites. The thousand grain weight (TGW) responded negatively to reduced fungicide application frequency. The critical stage in the assessment of pathogen pressure on wheat was the medium milk phase (BBCH 75). At this stage, indices of SPAD and leaf greenness together with indices of wheat infestation with pathogens allowed for a reliable prediction of both TGW and grain yield. It can be concluded that phosphites do not substitute organic fungicides in limiting pathogen pressure in winter wheat. Moreover, increased pressure of pathogens significantly reduces Nf productivity.

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40

Chen, Rui Xin, Ling Yan Xu, and Chang Feng Sun. "Three-Dimensional Open-Framework Zinc Phosphite: Synthesis and Characterization." Advanced Materials Research 455-456 (January 2012): 730–34. http://dx.doi.org/10.4028/www.scientific.net/amr.455-456.730.

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Generally, open-framework metal phosphites like phosphates, are synthesized under hydrothermal or solvothermal conditions in the presence of organic amines, which may act as structure-directing agent or template to avoid the formation of dense phase, but few of them has been successfully prepared at room temperature which seems to be difficult to synthesize these compounds. In this work, at room temperature, employing n-propylamine as a template, a three-dimensional zinc phosphite (C3H10N) 2·[Zn3(HPO3)4] has been prepared and characterized by single-crystal X-ray diffraction, FTIR, elemental analysis, powder X-ray diffraction, and thermogravimetric analysis. The compound crystallizes in the orthorhombic space group Pccn, with cell parameters, a = 9.839(3) Å, b = 23.356(8) Å, c = 8.970(3) Å, V = 2050.2(8) nm3 and Z = 4.

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41

Ramazanova, Kyzgaldak, Soumyadeep Chakrabortty, Bernd H. Müller, Peter Lönnecke, Johannes G. de Vries, and Evamarie Hey-Hawkins. "Synthesis of P-stereogenic 1-phosphanorbornane-derived phosphine–phosphite ligands and application in asymmetric catalysis." RSC Advances 13, no. 49 (2023): 34439–44. http://dx.doi.org/10.1039/d3ra07630j.

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A convenient synthesis of enantiopure mixed donor phosphine–phosphite ligands has been developed incorporating P-stereogenic phosphanorbornane and axially chiral bisnaphthols into one ligand structure.

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42

Pereira, Mariette M., Mário J. F. Calvete, Rui M. B. Carrilho, and Artur R. Abreu. "Synthesis of binaphthyl based phosphine and phosphite ligands." Chemical Society Reviews 42, no. 16 (2013): 6990. http://dx.doi.org/10.1039/c3cs60116a.

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43

Averbuch-Pouchot, M. T. "Structures of glycinium phosphite and glycylglycinium phosphite." Acta Crystallographica Section C Crystal Structure Communications 49, no. 4 (April 15, 1993): 815–18. http://dx.doi.org/10.1107/s0108270192010771.

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44

Heutz, Frank J. L., and Paul C. J. Kamer. "Modular solid-phase synthesis, catalytic application and efficient recycling of supported phosphine–phosphite ligand libraries." Dalton Transactions 45, no. 5 (2016): 2116–23. http://dx.doi.org/10.1039/c5dt03226a.

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45

Changko, Saowalak, Priscilla D. Rajakumar, Rosanna E. B. Young, and Saul Purton. "The phosphite oxidoreductase gene, ptxD as a bio-contained chloroplast marker and crop-protection tool for algal biotechnology using Chlamydomonas." Applied Microbiology and Biotechnology 104, no. 2 (December 2, 2019): 675–86. http://dx.doi.org/10.1007/s00253-019-10258-7.

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AbstractEdible microalgae have potential as low-cost cell factories for the production and oral delivery of recombinant proteins such as vaccines, anti-bacterials and gut-active enzymes that are beneficial to farmed animals including livestock, poultry and fish. However, a major economic and technical problem associated with large-scale cultivation of microalgae, even in closed photobioreactors, is invasion by contaminating microorganisms. Avoiding this requires costly media sterilisation, aseptic techniques during set-up and implementation of ‘crop-protection’ strategies during cultivation. Here, we report a strain improvement approach in which the chloroplast of Chlamydomonas reinhardtii is engineered to allow oxidation of phosphite to its bio-available form: phosphate. We have designed a synthetic version of the bacterial gene (ptxD)-encoding phosphite oxidoreductase such that it is highly expressed in the chloroplast but has a Trp→Opal codon reassignment for bio-containment of the transgene. Under mixotrophic conditions, the growth rate of the engineered alga is unaffected when phosphate is replaced with phosphite in the medium. Furthermore, under non-sterile conditions, growth of contaminating microorganisms is severely impeded in phosphite medium. This, therefore, offers the possibility of producing algal biomass under non-sterile conditions. The ptxD gene can also serve as a dominant marker for genetic engineering of any C. reinhardtii strain, thereby avoiding the use of antibiotic resistance genes as markers and allowing the ‘retro-fitting’ of existing engineered strains. As a proof of concept, we demonstrate the application of our ptxD technology to a strain expressing a subunit vaccine targeting a major viral pathogen of farmed fish.

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46

Hamblin, M. R., J. S. Flora, and B. V. L. Potter. "myo-Inositol phosphorothioates, phosphatase-resistant analogues of myo-inositol phosphates. Synthesis of dl-myo-inositol 1,4-bisphosphate and dl-myo-inositol 1,4-bisphosphorothioate." Biochemical Journal 246, no. 3 (September 15, 1987): 771–74. http://dx.doi.org/10.1042/bj2460771.

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Syntheses of a metabolite of the second messenger myo-inositol 1,4,5-trisphosphate, myo-inositol 1,4-bisphosphate, and an analogue, the 1,4-bisphosphorothioate, are reported, by using phosphite chemistry on (+/-)-1,2:4,5-di-isopropylidene-myo-inositol. The synthesis of (+/-)-1,2:4,5-di-isopropylidene 3,6-bis[di-(2-cyanoethyl)]phosphite provides an intermediate that can be oxidized to either the corresponding bisphosphate or bisphosphorothioate. myo-Inositol phosphorothioates are proposed as novel analogues of myo-inositol phosphates; their resistance to phosphatase-catalysed breakdown is reported.

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47

Biosca, Maria, Oscar Pàmies, and Montserrat Diéguez. "Ir–Biaryl phosphite–oxazoline catalyst libraries: a breakthrough in the asymmetric hydrogenation of challenging olefins." Catalysis Science & Technology 10, no. 3 (2020): 613–24. http://dx.doi.org/10.1039/c9cy02501d.

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48

León, Félix, Aleix Comas-Vives, Eleuterio Álvarez, and Antonio Pizzano. "A combined experimental and computational study to decipher complexity in the asymmetric hydrogenation of imines with Ru catalysts bearing atropisomerizable ligands." Catalysis Science & Technology 11, no. 7 (2021): 2497–511. http://dx.doi.org/10.1039/d0cy02390f.

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RuCl<sub>2</sub>(P–OP)(N–N) complexes containing an atropisomerizable phosphine–phosphite and a chiral diamine are effective catalyst precursors for the asymmetric hydrogenation of N-aryl imines following an outer-sphere mechanism.

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49

Jakob, Alexander, Heike Schmidt, Patrice Djiele, Yingzhong Shen, and Heinrich Lang. "Phosphane/phosphite silver(I) carboxylates as CVD precursors." Microchimica Acta 156, no. 1-2 (June 12, 2006): 77–81. http://dx.doi.org/10.1007/s00604-006-0592-z.

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50

Brynda, Jiří, Bohumil Kratochvíl, and Ivana Císařová. "The determination of crystal structure of chromium(II) phosphite dihydrate, CrHPO3 2 H2O." Collection of Czechoslovak Chemical Communications 52, no. 7 (1987): 1742–47. http://dx.doi.org/10.1135/cccc19871742.

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The crystal structure of CrHPO3.2 H2O has been solved by the heavy atom method. The compound crystallizes in the orthorhombic space group P212121 with the unit cell parameters a = 679·25(8), b = 915·61(8), c = 752·2(1) pm, Z = 4. The structure was refined to the final reliability factor R = 0·043 for 1 040 observed reflexions (I > 1·96σ(I)). The structure consists of chains formed by CrO6 octahedra connected each other in vertices. The chains are interconnected by phosphite tetrahedra HPO3. Hydrogen bridges of water-phosphite tetrahedron and water-water types form space cross-linking of the whole structure. Bond distances Cr-O in the tetragonally distorted octahedron range from 201·2 to 304·9 pm. The interatomic distances P-O in phosphite tetrahedron are between 152·1 and 152·7 pm. The degree of the distorsion DISQ of HPO3 tetrahedron and CrO6 octahedron is discussed on the basis of known structures of phosphites and chromium(II) compounds.

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