Phosphoric acid diesters phosphate

Phosphoric acid diesters are prepared by treating a liquid slurry of phosphate monoester with epoxides in the presence of alkali compounds. Thus a mixture of monolauryl phosphate sodium salt and triethyl amine in water was treated with glycidol at 80°C for 8 h to give 98% lauryl(2,3-dihydroxypropyl)phosphate sodium salt [13]. 

This property of organophosphate esters may be of environmental importance since phosphoric acid diesters are much more soluble and very little is known concerning the environmental toxicity of these compounds. The available data do not provide sufficient descriptions of the experimental methods to determine if the rates are reliable (Barnard et al. 1961 Ciba-Geigy 1984e, 1986 Howard and Deo 1979 Mayer et al. 1981 Wolfe 1980). The majority of reports provide only a minimum of information and exclude important facts such as the duration of the experiments and the concentration of buffers. Despite the lack of experimental detail, published rate constants for base-catalyzed hydrolysis appear to be reasonably consistent and suggest that the hydrolytic half-life of triphenyl phosphate will vary from... 

In this procedure a diacylglyceryl phosphate is first converted with CDI into a reactive phosphoric imidazolide, which is then treated with a labeled alcohol to give a labeled phosphoric acid diester 123... 

If the phosphate residue of a nucleotide reacts with the 3 -OH group of a second nucleotide, the result is a dinucleotide with a phosphoric acid diester structure. Dinucleotides of this type have a free phosphate residue at the 5 end and a free OH group at the 3 end. They can therefore be extended with additional mononucleotides by adding further phosphoric acid diester bonds. This is the way in which oligonucleotides, and ultimately polynucleotides, are synthesized. 

Ribonucleic acids (RNAs) are polymers consisting of nucleoside phosphate components that are linked by phosphoric acid diester bonds (see p.80). The bases the contain are mainly uracil, cytosine, adenine, and guanine, but many unusual and modified bases are also found in RNAs (B). 

By far the most common form is B-DNA (2). As discussed on p. 84, this consists of two antiparallel polydeoxynucleotide strands intertwined with one another to form a right-handed double helix. The backbone of these strands is formed by deoxyribose and phosphate residues linked by phosphoric acid diester bonds. 

DCC is also used in nucleotide chemistry to esterify a sugar hydroxyl group with a phosphate group in another nucleotide or oligonucleotide unit. Also p-styrene based polymers with a pyridyl-2-ethanol end group are reacted in pyridine with 3 -0-acetyl-desoxythimidine-5 -phosphate in the presence of DCC." The reaction of mono esters of phosphoric acid with alcohols or phenols, in the presence of DCC, affords phosphoric acid diesters in high yield." This reaction is widely used in nucleic acid chemistry. 

Mixed phosphoric acid diesters via pyridinium phosphate betaines... 

Phosphoric acid diesters. 1-Ethylpiperidinium phenyl phosphorohydrazidate allowed to react with the stoichiometric amount of ethanol in dry pyridine in the presence of iodine ethyl phenyl hydrogen phosphate. Y good. F. reactions s. D. M. Brown and N. K. Hamer, Proc. Chem. Soc. 1960, 212. 

NMR is suitable for determination of monoester, diester, and phosphoric acid in phosphate esters. Peaks for these compounds are well separated from each other and easily identified. Quantitative results show good agreement with HPLC data (16). 

Ion Exchanger Electrodes One of the most successful liquid membrane electrodes is selective toward calcium. Such an electrode relies on the ability of phosphate ions to form stable complexes with the calcium ion. It uses a liquid cation exchanger, consisting of an aliphatic diester of phosphoric acid... 

Phosphate Esters. An ester is formed by elimination of H20 and formation of a linkage between an acid and an alcohol (or phenol) (Fig. III-22). Phosphomonoesters, especially of monosaccharides, are very common (Fig. ffl-23). Because phosphoric acid is a tribasic acid, it can also form di- and triesters (Fig. III-24). Phosphotriesters are rarely found in nature, but diesters are extremely important, particularly as the fundamental linkage of the nucleic acid polymers, which are sequences of ri-bose (or deoxyribose) units linked by 3 —> 5 phos-phodiester bonds (see Fig. III-25). Like phosphoric acid, which has three dissociable protons (Fig. III-26), phosphomono- and phosphodiesters are acidic and typically ionize as shown in Fig. HI-27. Note the similarities between the pvalues for... 

Monoalkyl phosphate and phosphate esters are special types of phosphoms-contain-ing anionic surfactants that are of great industrial importance. They are used for flameproofing, as antistatic for textiles, for foam inhibition, as an extreme pressure (EP) lubricant additive, as a surfactant component for alkaline, and as acid cleaners and for special cosmetic preparations (5). The commercially available phosphate ester products are complex mixtures of monoester and diester, free phosphoric acid, and free nonionic. 

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