Synthesis and Enzymatic Incorporation of Modified Deoxyadenosine Triphosphates

Several deoxyadenosine triphosphates containing modifications at the 8-position have been synthesized. Suitably protected 8-bromodeoxyadenosines were coupled with five imidazole-containing moieties by nucleophilic aromatic substitution or Sonagashira coupling to give modified nucleosides that were then triphosphorylated. Incorporation assays were performed for these modified residues with many commercially available DNA polymerases, and it was found that two of the modified dATPs could be effectively taken up as substrates by Sequenase V2.0. These two residues are candidates for substrates in combinatorial selections in the search for improved catalysis from DNAzymes. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)