Phosphoric diimidazolides

With [32P]phosphoric diimidazolide, prepared from sulfinyldiimidazole or CDI and H332P04, the 5 -terminal monoester phosphate groups in various RNAs could be selectively phosphorylated (radioactive labeling method) 1571,1581... 

Adenosine 5 -a,/ ,/ -triphosphate (pseudo ATP = T-ATP) was obtained by treatment of the phosphoric diimidazolide of adenosine 5 -monophosphate with tributylammonium phosphate. It rearranges with CDI into ATP.1511... 

Labeled phosphoric acid triesters and diamides have been synthesized from phosphoric diimidazolide.tl92],tl93] This method was found to be superior to that involving the dichloridate (phosphoric dichlorides). 

Cyclic phosphoramidates (phosphoric amides) were obtained by the reaction of amino alcohols with a phosphoric diimidazolide.tl933,[2]... 

If one methyl group was introduced at C-2 in the imidazole moiety of the phosphoric diimidazolide the reaction rate of transphosphorylation was retarded.123 Introduction of a further alkyl group at C-4 in the imidazole unit diminished the reactivity of the diimidazolide to such an extent that the second imidazole moiety could not be replaced.[ 1933... 

A difluorophosphate can be obtained from a phosphorous diimidazolide as demonstrated by the synthesis of a thymidine 5 -difluorophosphate. The diimidazolide was constructed from 3 -dimethoxytritylthymidine and triimidazolylphosphine.[202],[203]... 

Other bisazolides of phosphoric acid include O-phenylphosphoric diimidazolide and -ditriazolide O-phenylphosphoric diimidazolide, for instance, has been prepared from phenylphosphordichloridate and four equivalents of imidazole in benzene. 

In the reaction of a phosphoric ester diimidazolide (for preparation see Section 2.2) with an alcohol it is possible to substitute either one or two of the imidazole groups. 

Access to diphosphates (pyrophosphates) and triphosphates is provided through the reaction of phosphoric mono- or diimidazolides with a monoester phosphate. 

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