Synthesis of Oligonucleotides Containing Fapy dG (N~6-(2-Deoxy-alpha,beta-D-erythropentofuranosyl)-2,6-diamino-4-hydroxy-5-formamidopyrimidine)Using a 5'-Dimethoxytrityl Dinucleotide Phosphoramidite

摘要

Fapy centre dot dG(N~6-(2-deoxy-alpha,beta-D-erythropentofuranosyl)-2,6-diarnino-4-hydroxy-5-formamidopyrimidine)is a modified purine lesion produced by a variety of DNA-damaging agents,which shows interesting biochemical properties.The previous method for synthesizing oligonucleotides containing Fapy dG utilized a reverse dinucleotide phosphoramidite,which also required the synthesis of the appropriate reverse phosphoramidites.An improved method for synthesizing oligonucleotides containing FapydG,which does not require reverse phosphoramidites,is described.FapydG containing dinucleotide phosphoramidites containing 5'-thymidine(lla)or 5'-deoxycytidine(15)are prepared and employed in pligonucleotide synthesis.Oligonucleotide purity is assayed using the DNA repair enzyme formamidopyrimidine DNA glycosylase and by ESI-MS.