title: A simple and convenient synthesis of 3'-5'- or 2'-5'-linked oligoribonucleotide by polymerization of unprotected ribonucleoside using phosphorus tris-azole.
abstract: Oligoribonucleotides have been synthesized directly from unprotected ribonucleosides by a chemical polymerization approach using phosphorus tris-azoles. The procedure involves two steps: (i) the reaction of unprotected ribonucleoside with phosphorus tris-azole and (ii) the in situ oxidation of the resulting phosphite with iodine and water. Several phosphorus tris-azoles were investigated for generating oligoribonucleotide chains. Phosphorus tris-azoles of which azoles are imidazole, 2-methylimidazole, and 2-ethyl-4-methylimidazole were found to be most effective. Uridine, adenosine, and cytidine oligonucleotides were obtained rapidly in high yields without any protection. The inter-ribonucleotidic linkage of the oligomers consists of 3'-5'- and 2'-5'-linkages. The linkage isomers were easily separated by a reverse phase column chromatography. The present approach provides a convenient and potentially useful method for preparing 3'-5'- or 2'-5'-linked oligoribonucleotides.
mesh_terms: D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D002851:Chromatography, High Pressure Liquid; D007202:Indicators and Reagents; D009841:Oligonucleotides / Q000138:chemical synthesis*; D009843:Oligoribonucleotides / Q000138:chemical synthesis*; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D010766:Phosphorylation; D012263:Ribonucleosides; D013154:Spleen / Q000201:enzymology; D014230:Triazoles
chemical_list: D007202:Indicators and Reagents; D009841:Oligonucleotides; D009843:Oligoribonucleotides; D012263:Ribonucleosides; D014230:Triazoles; D010727:Phosphoric Diester Hydrolases