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Ludwig Maier - One of the best experts on this subject based on the ideXlab platform.
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Organic Phosphorus Compounds 106 1 a 31p nmr study of phosphinous phosphinic and thiophosphinic amides
Phosphorus Sulfur and Silicon and The Related Elements, 1996Co-Authors: Ludwig Maier, Peter J. DielAbstract:Abstract The synthesis, physical, chemical and spectroscopic properties of eight different types of phosphinous-, phosphinic- and thiophosphinic amides are reported. It is shown that the 31P-chem. shifts of tertiary amides are at lower magnetic field than that of secondary amides. As an exception, in the bis(tertiary butyl) series this trend is reversed.
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Organic Phosphorus Compounds 1051 synthesis and properties of 2 amino 2 arylethylphosphonic acids and derivatives
Phosphorus Sulfur and Silicon and The Related Elements, 1995Co-Authors: Ludwig Maier, Peter J. DielAbstract:Abstract 2-Amino-2-arylethylphosphonic acids, 6a to 6q have been prepared from the corresponding 2-acetoxyimino-or 2-methoxyimino-2-aryl-ethylphosphonates, 3 or 4, by hydrogenation using Raney-Ni as a catalyst, followed by hydrolysis with HCl. 3 and 4 were obtained from the corresponding aryl-bromomethyl-ketoxime-O-acetates, 1, or aryl-bromomethyl-O-methylketoximes, 2, by an Arbuzov reaction with triethylphosphite. Several of the 2-amino-2-arylethylphosphonic acids 6 show activity against Botrytis cinerea and Cercospora. Among the more active Compounds were 6a, 6b, 6g and 6k, whereby 6b and 6k gave full protection against Botrytis cinerea (on apple) down to 60 ppm. The same Compounds show also a weak inhibition of anthocyanin synthesis in vivo.
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Organic Phosphorus Compounds 101 1 preparation and physical properties of bis aminoalkyl phosphinic acids
Phosphorus Sulfur and Silicon and The Related Elements, 1992Co-Authors: Ludwig MaierAbstract:Abstract The synthesis, physical and spectroscopic properties of 3-amino-propyl-aminomethylphosphinic acid, 5, bis(2-aminoethyl)phosphinic acid, 8, and of bis(3-aminopropyl)phosphinic acid, 10, are reported.
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Organic Phosphorus Compounds 103 1 aminooxyalkylphosphinic acids and aminooxyalkylphospine oxides and derivatives
Phosphorus Sulfur and Silicon and The Related Elements, 1992Co-Authors: Ludwig Maier, H SporriAbstract:Abstract Condensation of α-hydroxyalkylphosphinates, 1, with N-hydroxy-phtalimide, using Mitsunobu's condition, yields 1-phthalimido-N-oxyalkylphosphinates, 2, which on treatment with hydrazine give 1-aminooxyalkylphosphinates, 3. Hydrolysis of these produces 1-aminooxyalkylphosphinic acids, 4. Two 1-aminooxyalkyl-dimethyl-phosphine oxides, 7, are also described. The physical properties of these Compounds are listed and the biological activity of some Compounds is reported.
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Organic Phosphorus Compounds 102 1 aminooxyalkylphosphonic acids and derivatives
Phosphorus Sulfur and Silicon and The Related Elements, 1992Co-Authors: Ludwig Maier, H SporriAbstract:Abstract Condensation of α-hydroxyalkylphosphonates, 1, with N-hydroxy-phthalimide using Mitsunobu's condition yields 1-phthalimido-N-oxyalkylphosphonates, 2, which on treatment with hydrazine give 1-aminooxyalkylphosphonates, 3. Hydrolysis of these with HCl produces 1-aminooxyalkylphosphonic acids, 4, in good yield. The reactions of 3 with dinitrodiphenyl ether, isocyanides, aldehydes and ketones are also reported. 1-Aminooxy-2-phenylethylphosphonic acid, 4g, is only a weak inhibitor of PAL, but 4i is a good inhibitor of anthocyanin synthesis. 4g exhibits weak antifungal activity (against Botrytis cinerea) and 5a and 5b show herbicidal activity against dicotyledonous weeds.
Peter J. Diel - One of the best experts on this subject based on the ideXlab platform.
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Organic Phosphorus Compounds 106 1 a 31p nmr study of phosphinous phosphinic and thiophosphinic amides
Phosphorus Sulfur and Silicon and The Related Elements, 1996Co-Authors: Ludwig Maier, Peter J. DielAbstract:Abstract The synthesis, physical, chemical and spectroscopic properties of eight different types of phosphinous-, phosphinic- and thiophosphinic amides are reported. It is shown that the 31P-chem. shifts of tertiary amides are at lower magnetic field than that of secondary amides. As an exception, in the bis(tertiary butyl) series this trend is reversed.
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Organic Phosphorus Compounds 1051 synthesis and properties of 2 amino 2 arylethylphosphonic acids and derivatives
Phosphorus Sulfur and Silicon and The Related Elements, 1995Co-Authors: Ludwig Maier, Peter J. DielAbstract:Abstract 2-Amino-2-arylethylphosphonic acids, 6a to 6q have been prepared from the corresponding 2-acetoxyimino-or 2-methoxyimino-2-aryl-ethylphosphonates, 3 or 4, by hydrogenation using Raney-Ni as a catalyst, followed by hydrolysis with HCl. 3 and 4 were obtained from the corresponding aryl-bromomethyl-ketoxime-O-acetates, 1, or aryl-bromomethyl-O-methylketoximes, 2, by an Arbuzov reaction with triethylphosphite. Several of the 2-amino-2-arylethylphosphonic acids 6 show activity against Botrytis cinerea and Cercospora. Among the more active Compounds were 6a, 6b, 6g and 6k, whereby 6b and 6k gave full protection against Botrytis cinerea (on apple) down to 60 ppm. The same Compounds show also a weak inhibition of anthocyanin synthesis in vivo.
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Organic Phosphorus Compounds 97 1 synthesis and properties of 1 amino 2 aryl and 2 pyridyl ethylphosphonic acids and derivatives
Phosphorus Sulfur and Silicon and The Related Elements, 1991Co-Authors: Ludwig Maier, Peter J. DielAbstract:Abstract 1-Amino-2-(o, m, and p-pyridyl)-ethylphosphonic acids, 5α, 5β and 5γ, have been prepared by alkylation of benzylideneaminomethylphosphonate, followed by hydrogenation and hydrolysis, whereas 1-amino- 2-(o, m, and p-methoxyphenyl)-ethyl phosphonic acids, 5i, 5k, and 51 and some other derivatives were obtained from the oximes by hydrogenation and hydrolysis. 1-Amino-2-pyridylethylphosphonic acids, 5α, 5β, and 5γ, and 1-amino-2-(alkoxy-substituted phenyl)- ethylphosphonic acids, 51, 5m, and 5n and others such as 5u show activity against Botrytis cinerea (on apple) and Cercospora (on peanuts). 5q is an inhibitor of anthocyanin synthesis in vivo. 3t exhibits activity against Piricularia (on rice) and 3w is active against Phytophthora (on tomato) and Plasmopora (on grapes).
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Organic Phosphorus Compounds 941 preparation physical and biological properties of amino arylmethylphosphonic and phosphonous acids
Phosphorus Sulfur and Silicon and The Related Elements, 1991Co-Authors: Ludwig Maier, Peter J. DielAbstract:Abstract The preparation, physical and spectroscopic properties of amino-arylmethylphosphonic- and -phosphonous acids, the Phosphorus analogues of phenylglycine, are described. It is shown that several of the Compounds prepared exhibit antifungal activity at 200 ppm. Thus 1e, 1f, 1g and 1h showed activity against Erysiphe (barley), 2a against Puccinia (wheat) and 6a against Botrytis (apple). Of particular interest is the high gameticidal activity of 3a in the greenhouse.
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Organic Phosphorus Compounds 92.1 SYNTHESIS AND PROPERTIES OF AZETIDINE-3-PHOSPHONIC- AND 3-PHOSPHONOUS ACID
Phosphorus Sulfur and Silicon and the Related Elements, 1991Co-Authors: Peter J. Diel, Ludwig MaierAbstract:Abstract Azetidine-3-phosphonic acid, 4a, and azetidine-3-phosphonous acid. 4b, have been prepared by the interaction of I-benzhydryl-3-methanesulfonato-azetidine with sodium phosphite or sodium O-ethyl-diethoxymethylphosphonite, followed by catalytic debenzhydrylation with HZ and hydrolysis. Neither acid shows biological activity.
Benjamin L. Turner - One of the best experts on this subject based on the ideXlab platform.
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Determination of neo- and d-chiro-Inositol Hexakisphosphate in Soils by Solution 31P NMR Spectroscopy
2015Co-Authors: Benjamin L. Turner, Alexander W Cheesman, Yasmin H Godage, Andrew M. Riley, Barry V L PotterAbstract:The inositol phosphates are an abundant but poorly understood group of Organic Phosphorus Compounds found widely in the environment. Four stereoisomers of inositol hexakisphosphate (IP6) occur, although for three of these (scyllo, neo, and d-chiro) the origins, dynamics, and biological function remain unknown, due in large part to analytical limitations in their measurement in environmental samples. We synthesized authentic neo- and d-chiro-IP6 and used them to identify signals from these Compounds in three soils from the Falkland Islands. Both Compounds resisted hypobromite oxidation and gave quantifiable 31P NMR signals at δ = 6.67 ppm (equatorial phosphate groups of the 4-equatorial/2-axial conformer of neo-IP6) and δ = 6.48 ppm (equatorial phosphate groups of the 2-equatorial/4-axial conformer of d-chiro-IP6) in soil extracts. Inositol hexakisphosphate accounted for 46–54% of the soil Organic Phosphorus, of which the four stereoisomers constituted, on average, 55.9% (myo), 32.8% (scyllo), 6.1% (neo), and 5.2% (d-chiro). Reappraisal of the literature based on the new signal assignments revealed that neo- and d-chiro-IP6 occur widely in both terrestrial and aquatic ecosystems. These results confirm that the inositol phosphates can constitute a considerable fraction of the Organic Phosphorus in soils and reveal the prevalence of neo- and d-chiro-IP6 in the environment. The hypobromite oxidation and solution 31P NMR spectroscopy procedure allows the simultaneous quantification of all four IP6 stereoisomers in environmental samples and provides a platform for research into the origins and ecological significance of these enigmatic Compounds
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variability in potential to exploit different soil Organic Phosphorus Compounds among tropical montane tree species
Functional Ecology, 2015Co-Authors: Brian S Steidinger, Benjamin L. Turner, Adrianna Corrales, James W DallingAbstract:Summary We hypothesized that tropical plant species with different mycorrhizal associations reduce competition for soil Phosphorus (P) by specializing to exploit different soil Organic P Compounds. We assayed the activity of root/mycorrhizal phosphatase enzymes of four tree species with contrasting root symbiotic relationships – arbuscular mycorrhizal (AM) (angiosperm and conifer), ectomycorrhizal (EM) and non-mycorrhizal – collected from one of three soil sites within a montane tropical forest. We also measured growth and foliar P of these seedlings in an experiment with P provided exclusively as inOrganic orthophosphate, a simple phosphomonoester (glucose phosphate), a phosphodiester (RNA), phytate (the sodium salt of myo-inositol hexakisphosphate) or a no-P control. The EM tree species expressed twice the phosphomonoesterase activity as the AM tree species, but had similar phosphodiesterase activity. The non-mycorrhizal Proteaceae tree had markedly greater activity of both enzymes than the mycorrhizal tree species, with root clusters expressing greater phosphomonoesterase activity than fine roots. Both the mycorrhizal and non-mycorrhizal tree species contained significantly greater foliar P than in no-P controls when limited to inOrganic phosphate, glucose phosphate and RNA. The EM species did not perform better than the AM tree species when limited to Organic P in any form. In contrast, the non-mycorrhizal Proteaceae tree was the only species capable of exploiting phytate, with nearly three times the leaf area and more than twice the foliar P of the no-P control. Our results suggest that AM and EM tree species exploit similar forms of P, despite differences in phosphomonoesterase activity. In contrast, the mycorrhizal tree species and non-mycorrhizal Proteaceae appear to differ in their ability to exploit phytate. We conclude that resource partitioning of soil P plays a coarse but potentially ecologically important role in fostering the coexistence of tree species in tropical montane forests.
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Article pubs.acs.org/est Determination of neo- and D-chiro-Inositol Hexakisphosphate in Soils by Solution 31 P NMR Spectroscopy
2013Co-Authors: Benjamin L. Turner, Andrew M. Riley, Yasmin H Godage, Er W. Cheesman, Barry V L PotterAbstract:*S Supporting Information ABSTRACT: The inositol phosphates are an abundant but poorly understood group of Organic Phosphorus Compounds found widely in the environment. Four stereoisomers of inositol hexakisphosphate (IP6) occur, although for three of these (scyllo, neo, and D-chiro) the origins, dynamics, and biological function remain unknown, due in large part to analytical limitations in their measurement in environmental samples. We synthesized authentic neo- and D-chiro-IP6 and used them to identify signals from these Compounds in three soils from the Falkland Islands. Both Compounds resisted hypobromite oxidation and gave quantifiable 31P NMR signals at δ = 6.67 ppm (equatorial phosphate groups of the 4-equatorial/2-axial conformer of neo-IP6) and δ = 6.48 ppm (equatorial phosphate groups of the 2-equatorial/4-axial conformer of D-chiro-IP6) in soil extracts. Inositol hexakisphosphate accounted for 46−54 % of the soil Organic Phosphorus, of which the four stereoisomers constituted, on average, 55.9 % (myo), 32.8 % (scyllo), 6.1 % (neo), and 5.2 % (D-chiro). Reappraisal of the literature based on the new signal assignments revealed that neo- and D-chiro-IP6 occur widely in both terrestrial and aquatic ecosystems. These results confirm that the inositol phosphates can constitute a considerabl
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determination of neo and d chiro inositol hexakisphosphate in soils by solution 31p nmr spectroscopy
Environmental Science & Technology, 2012Co-Authors: Benjamin L. Turner, Andrew M. Riley, Alexander W Cheesman, Yasmin H Godage, Barry V L PotterAbstract:The inositol phosphates are an abundant but poorly understood group of Organic Phosphorus Compounds found widely in the environment. Four stereoisomers of inositol hexakisphosphate (IP6) occur, although for three of these (scyllo, neo, and d-chiro) the origins, dynamics, and biological function remain unknown, due in large part to analytical limitations in their measurement in environmental samples. We synthesized authentic neo- and d-chiro-IP6 and used them to identify signals from these Compounds in three soils from the Falkland Islands. Both Compounds resisted hypobromite oxidation and gave quantifiable 31P NMR signals at δ = 6.67 ppm (equatorial phosphate groups of the 4-equatorial/2-axial conformer of neo-IP6) and δ = 6.48 ppm (equatorial phosphate groups of the 2-equatorial/4-axial conformer of d-chiro-IP6) in soil extracts. Inositol hexakisphosphate accounted for 46–54% of the soil Organic Phosphorus, of which the four stereoisomers constituted, on average, 55.9% (myo), 32.8% (scyllo), 6.1% (neo), ...
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resource partitioning for soil Phosphorus a hypothesis
Journal of Ecology, 2008Co-Authors: Benjamin L. TurnerAbstract:Summary 1. Organic Phosphorus is abundant in soil and its turnover can supply a considerable fraction of the Phosphorus taken up by natural vegetation. Despite this, the ecological significance of Organic Phosphorus remains poorly understood, which is remarkable given the biological importance of Phosphorus in terrestrial environments. 2. Of particular interest is the possibility that coexisting plant species partition soil Organic Phosphorus to reduce competition. This seems likely given the large number of biologically available Phosphorus Compounds that occur in soil and the variety of mechanisms by which plants can utilize them. 3. Here I propose a conceptual model of resource partitioning for soil Phosphorus. The model describes a hypothetical example of four coexisting plant species that differ in their ability to access soil Organic Phosphorus Compounds, which are grouped to form a gradient of biological availability based on the processes involved in their utilization by plants. 4. Synthesis: Resource partitioning for soil Phosphorus could provide an additional mechanism to
Emil Rydin - One of the best experts on this subject based on the ideXlab platform.
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screening for Organic Phosphorus Compounds in aquatic sediments by liquid chromatography coupled to icp aes and esi ms ms
Analytical Chemistry, 2008Co-Authors: Heidi De Brabandere, Emil Rydin, Niklas Forsgard, Lena Israelsson, Jean Petterson, Monica Waldeback, Per J R SjobergAbstract:The structures of Organic phosphorous (P) Compounds in aquatic sediments are to a large extent unknown although these Compounds are considered to play an important role in regulating lake trophic status. To enhance identification of these Compounds, a liquid chromatography (LC) method for their separation was developed. The stationary phase was porous graphitic carbon (PGC), and the mobile phases used in the gradient elution were compatible with both inductive coupled plasma atomic emission spectroscopy (ICP-AES) and electrospray ionization tandem mass spectrometry (ESI-MS/MS). With LC-ICP-AES, eight different P containing peaks could be observed in the P chromatogram indicating that at least eight different P Compounds were separated. With the setup of an information dependent acquisition (IDA) with ESI-MS/MS, the mass over charge (m/z) of Compounds containing a phosphate group (H2PO3−, m/z 97) could be measured and further fragmentation experiments gave additional information on the structure of almost ...
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degradation of Organic Phosphorus Compounds in anoxic baltic sea sediments a 31p nuclear magnetic resonance study
Limnology and Oceanography, 2006Co-Authors: Joakim Ahlgren, Kasper Reitzel, Lars J Tranvik, Adolf Gogoll, Emil RydinAbstract:The composition and abundance of Phosphorus extracted by NaOH-ethylenediaminetetraacetic acid from anoxic Northwest Baltic Sea sediment was characterized and quantified using solution P-31 nuclear ...
C Von Sperber - One of the best experts on this subject based on the ideXlab platform.
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the oxygen isotope composition of phosphate released from phytic acid by the activity of wheat and aspergillus niger phytase
Biogeosciences, 2015Co-Authors: Federica Tamburini, C Von Sperber, Benjamin Brunner, Stefano M Bernasconi, Emmanuel FrossardAbstract:Abstract. Phosphorus (P) is an essential nutrient for living organisms. Under P-limiting conditions plants and microorganisms can exude extracellular phosphatases that release inOrganic phosphate (Pi) from Organic Phosphorus Compounds (Porg). Phytic acid (myo-inositol hexakisphosphate, IP6) is an important form of Porg in many soils. The enzymatic hydrolysis of IP6 by phytase yields available Pi and less phosphorylated inositol derivates as products. The hydrolysis of Organic P Compounds by phosphatases leaves an isotopic imprint on the oxygen isotope composition (δ18O) of released Pi, which might be used to trace P in the environment. This study aims at determining the effect of phytase on the oxygen isotope composition of released Pi. For this purpose, enzymatic assays with histidine acid phytases from wheat and Aspergillus niger were prepared using IP6, adenosine 5'-monophosphate (AMP) and glycerophosphate (GPO4) as substrates. For a comparison to the δ18O of Pi released by other extracellular enzymes, enzymatic assays with acid phosphatases from potato and wheat germ with IP6 as a substrate were prepared. During the hydrolysis of IP6 by phytase, four of the six Pi were released, and one oxygen atom from water was incorporated into each Pi. This incorporation of oxygen from water into Pi was subject to an apparent inverse isotopic fractionation (v ~ 6 to 10 ‰), which was similar to that imparted by acid phosphatase from potato during the hydrolysis of IP6 (v ~ 7 ‰), where less than three Pi were released. The incorporation of oxygen from water into Pi during the hydrolysis of AMP and GPO4 by phytase yielded a normal isotopic fractionation (v ~ −12 ‰), similar to values reported for acid phosphatases from potato and wheat germ. We attribute this similarity in v to the same amino acid sequence motif (RHGXRXP) at the active site of these enzymes, which leads to similar reaction mechanisms. We suggest that the striking substrate dependency of the isotopic fractionation could be attributed to a difference in the δ18O values of the C–O–P bridging and non-bridging oxygen atoms in Organic phosphate Compounds.