Organic Phosphorus Compound Analysis

Organic Phosphorus Compounds, Determination of, by Phosphate Analysis... 

Phosphate Analysis, Determination of Organic Phosphorus Compound by (Lindberg... 

Lindberg, Olov, and Emster, Lars, Determiimtion of Organic Phosphorus Compounds by Phosphate Analysis. 3 1... 

Separate quantitative determination of orthophosphate, hydrolyzable phosphates and organic phosphorus compounds is not possible with the means offered by conventional water analysis if these substances are present together in dissolved form, since in the course of hydrolysis not only orthophosphates but also organic phosphate compounds are partially codetected. 

The analysis of complex organic phosphorus compounds, particularly biopolymers such as phos-phoproteins, lipids and nucleic acids, now relies heavily on combinations of chemical, enzymatic and physical methods (see below). 

Lindberg, 0., and L. Ernster Determination of organic phosphorus compounds by phosphate analysis. In Methods of biochemical analysis, Vol. 3, p. 1. Ed. D. Glick. New York Interscience Publishers 1956. 

Phenolic Compounds of Interest in Metabolism (Bray and Thorpe)... Phosphate Analysis, Determination of Organic Phosphorus Compounds by (Lindberg and Ernster). 

Magnesium-induced coprecipitation (Karl and Tien, 1992) involves the precipitation of brucite (Mg(OH)2) from seawater by the addition of base. It was observed that phosphorus compounds, including organic phosphates, coprecipitate with the brucite, and this was used as the basis for preconcentration of phosphorus prior to analysis of total phosphorus in the collected precipitate. Nucleic acids have also been determined quantitatively by precipitation with cetyltri-methylammonium bromide, with DNA and RNA determined at xg/l levels by fluoromet-ric and colorimetric procedures (Karl and Bailiff, 1989). Iron and barium salts are also commonly used as precipitants to isolate inositol phosphates after selective oxidation of organic phosphorus (Cosgrove, 1980). 

NMR spectroscopy was first used on soil extracts by Newman and Tate (1980), and since then has advanced our knowledge of organic phosphorus in soils and environmental samples more than any other technique. Phosphorus NMR spectroscopy may be used on solid or extracted samples, with the advantage that all phosphorus species in a sample can be characterized simultaneously without the need for complex cleanup and chromatographic separation procedures. However, the heterogeneous physical and chemical properties of soils, relatively low phosphorus concentrations, and the natural association of phosphorus with paramagnetic ions such as iron and manganese, make P NMR analysis of soil samples more complicated than studies of purified compounds. Phosphorus NMR experiments on environmental samples... 

Both filterable and particulate forms of organic phosphorus are transferred from soils, but the lack of suitable techniques for determining specific phosphorus compounds in aqueous samples means that there is little information available on the chemical composition of either fraction. Conceptual understanding of organic phosphorus forms and their behaviour in water is also limited by the operational definitions that arise from conventional analysis procedures (see below). For detailed reviews of speciation techniques for organic phosphorus in soil waters see McKelvie (Chapter 1, this volume) and Cooper et al. (Chapter 3, this volume). 

Continuing studies on the application of organic phosphorus and sulfur compounds for the synthesis of 1,4-dicarbonyl compounds and functionalized cyclopentenones, Mikolajczyk and Zatorski [17] developed a short and efficient synthesis of methylenomycin B starting from and y-ketophosphonates 2 and 3. These two reagents were revealed by retro synthetic analysis shown in Scheme 1. 

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