The synthesis of 2-pyrimidinone nucleosides and their incorporation into oligodeoxynucleotides.
The synthesis of 1-(beta-D-2'-deoxyribosyl)-2-pyrimidinone (dK) and its 5-methyl derivative (d5) from 2'-deoxycytidine or 2'-deoxythymidine, respectively, via silver oxide oxidation of 4-hydrazinopyrimidines is described. The necessary hydrazine substituted pyrimidine nucleosides have been prepared by transamination of a protected cytidine derivative or by addition/elimination reactions to an O4-sulfonated thymidine derivative. Oxidation of the 4-hydrazino pyrimidines was complicated by a competing hydrolytic reaction which generated 2'-deoxyuridine or 2'-deoxythymidine. However, in the presence of an organic base such as triethylamine, oxidation became the predominant reaction. After suitable protection and formation of the 3'-phosphoramidite derivatives, these modified nucleosides were incorporated into seven self-complementary oligodeoxynucleotides by chemical synthesis using phosphite triester methodology. Oligodeoxynucleotides were prepared such that dA-dT and dG-dC base pairs were substituted by dA-d5 or dG-dK base pairs, respectively. Both circular dichroism spectra and thermal denaturation studies were used to characterize the modified oligodeoxynucleotides.
Gildea
B
B
Department of Chemistry, Boston College, Chestnut Hill, MA 02167.
McLaughlin
L W
LW
D001483:Base Sequence; D055598:Chemical Phenomena; D002621:Chemistry; D002851:Chromatography, High Pressure Liquid; D002942:Circular Dichroism; D003841:Deoxycytidine; D006358:Hot Temperature; D006834:Hydrazines; D006868:Hydrolysis; D008745:Methylation; D009690:Nucleic Acid Conformation; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis*; D009994:Osmolar Concentration; D010084:Oxidation-Reduction; D011741:Pyrimidine Nucleosides / Q000138:chemical synthesis*; D013936:Thymidine
D006834:Hydrazines; D009838:Oligodeoxyribonucleotides; D011741:Pyrimidine Nucleosides; D003841:Deoxycytidine; C059189:1-(2'-deoxyribosyl)-2-pyrimidinone; D013936:Thymidine