Substrate properties of dinucleoside 5?,5?-oligophosphates in the reactions catalyzed by HIV reverse transcriptase, E. coli DNA polymerase I, and E. coli RNA polymerase

Synthesis of Nucleoside-5'-O-Tetraphosphates from Activated Trimetaphosphate and Nucleoside-5'-O-Monophosphates

This article describes a straight-forward chemical method for the synthesis of nucleoside-5'-O-tetraphosphates, such as cytosine-, guanosine-, adenosine-, and uridine-5'-O-tetraphosphates, starting from the corresponding nucleoside monophosphates and trimetaphosphate, a readily available and inexpensive starting material. The procedure involves reacting the tri(tetrabutylammonium) salt of trimetaphosphate with mesitylenesulfonyl chloride and N-methylimidazole. The resulting activated cyclic trimetaphosphate is reacted with the tetrabutylammonium salts of nucleoside monophosphates. After quenching the reaction with buffer and high-performance liquid chromatography purification, the desired nucleoside-5'-O-tetraphosphates were obtained in yields of 84% to 86%. © 2018 by John Wiley & Sons, Inc.

Synthesis of nucleoside tetraphosphates and dinucleoside pentaphosphates via activation of cyclic trimetaphosphate

A procedure for the synthesis of dinucleoside 5'-pentaphosphates (Np5N) and nucleoside 5'-tetraphosphates (Np4) is described. The procedure relies on the activation of cyclic trimetaphosphate followed by a reaction with a nucleoside 5'-monophosphate (NMP) to give intermediates of type 3. Reaction of 3 with water or an NMP gives the desired products in yields ranging from 77 to 86%.

Modifications to the dNTP triphosphate moiety: from mechanistic probes for DNA polymerases to antiviral and anti-cancer drug design

Abnormal replication of DNA is associated with many important human diseases, most notably viral infections and neoplasms. Existing approaches to chemotherapeutics for diseases associated with dysfunctional DNA replication classically involve nucleoside analogues that inhibit polymerase activity due to modification in the nucleobase and/or ribose moieties. These compounds must undergo multiple phosphorylation steps in vivo, converting them into triphosphosphates, in order to inhibit their targeted DNA polymerase. Nucleotide monophosphonates enable bypassing the initial phosphorylation step at the cost of decreased bioavailability. Relatively little attention has been paid to higher nucleotides (corresponding to the natural di- and triphosphate DNA polymerase substrates) as drug platforms due to their expected poor deliverability. However, a better understanding of DNA polymerase mechanism and fidelity dependence on the triphosphate moiety is beginning to emerge, aided by systematic incorporation into this group of substituted methylenebisphosphonate probes. Meanwhile, other bridging, as well as non-bridging, modifications have revealed intriguing possibilities for new drug design. We briefly survey some of this recent work, and argue that the potential of nucleotide-based drugs, and intriguing preliminary progress in this area, warrant acceptance of the challenges that they present with respect to bioavailability and metabolic stability.

Solid-phase synthesis of symmetrical 5',5'-dinucleoside mono-, di-, tri-, and tetraphosphodiesters

Four classes of phosphitylating reagents were subjected to reactions with aminomethyl polystyrene resin-bound p-acetoxybenzyl alcohol to yield the corresponding polymer-bound mono-, di-, tri-, and tetraphosphitylating reagents. The solid-phase reagents were reacted with unprotected nucleosides (e.g., thymidine, adenosine, 3'-azido-3'-deoxythymidine, cytidine, or inosine) in the presence of 5-(ethylthio)-1H-tetrazole. Polymer-bound nucleosides underwent oxidation with tert-butyl hydroperoxide, deprotection of cyanoethoxy groups with DBU, and the acidic cleavage, respectively, to afford 5',5'-dinucleoside mono-, di-, tri-, and tetraphosphodiesters in 59-78% yield.