DiPhosphoric add

Adenylic acid 5 -(dihydrogen phosphate), 9CI. Adenosine 2, 5 -bis(phosphate), SCI. Adenosine 2, 5 -diphosphoric add... 

Polymerization initiated by phosphoric or metaphosphoric add, or their alkylammonium salts, in the absence of water, proceeds probably through a hydrolytic mechanism. Indeed, phosphoric acid at the polymerization temperatures rmdetgoes dehydration and the lactam amide group is then hydrolyzed. The resultant diphosphoric add catalyzes both hydrolysis and propagation. 

Phosphorylation. Chambers et al. found the reagent useful for the preparation of nucleoside diphosphoric acids (3, R —adenine, uracil, etc.). A nucleotide (I) is converted into the 5 -phosphoramidate (2) by reaction with ammonia and dicyclo-hexylcarbodiimide (DCC), and the amidate (2) is treated with dioxane diphosphate in o-chlorophenol (3 hrs..0 ). The diphosphoric acid (3) is precipitated with petroleum ether and purified as the ammonium salt. Yields are around 90%, whereas when 8.5% phosphoric add was used yields were in the order of 50-60%. However, anhydrous... 

Phosporus exists in the sea in the form of ions of (ortho) phosphoric acid, H3PO4. About 10% of the inorganic phosphate in seawater is present as PO4 and practically all the remaining phosphate exists as HPO4. The condensed phosphoric acids, L, diphosphoric acid, H4P2O7, and all polyphosphoric adds with P-O-P linkages, have so far not been detected in open seawaters but are known to occur in estuarine and coastal waters as a result of pollution with detergents. 

Orthophosphoric acid, H3PO4, undergoes condensation reactions to form other phosphoric acids. For example, two orthophosphoric add molecules condense to form diphosphoric acid (also called pyrophosphoric acid). ... 

PhospJioric Add. On heating trioxyunethylene (parafoimaldehyde or polyosymethylene) with anhydrous phosphoric acid at 140-145°C, Con-tardp obtained methylene diphosphoric acid, CH2(H2p04)2, in the form of a stmw-colored symp. The calcium and barium gaits of this acid are only slightly soluble in cold water and less soluble in hot water. When heated to 400 C, these salts lose their formaldehyde quantitatively. On addition of phosphoms peiitoxide to 37 per cent formaldehyde, heat is... 

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