title: Chemical synthesis of 2',5'-oligoribonucleotides.
abstract: Partial phenylcarbamoylation of ribonucleosides by metal carboxylates - phenyl isocyanate system was found to be induced at 2'-position with high regioselectivity in good yields, similar to that by amines - phenyl isocyanate system; these results prompted us to perform synthesis of oligoribonucleotides bearing 2'-5' phosphodiester linkage starting either from 5'-0-acetyl-2'-0-phenylcarbamoyl or from 2', 5'-bis(phenylcarbamo)yl derivatives through the sequence of reactions, i.e. tetrahydropyranylation at 3'-position, decarbamoylation and deacylation with sodium methoxide in methanol both at 2'- and 5'-positions, dimethoxytritylation at 5'-position, and phosphorylation at 2'-position with 5-chloro-8-quinolylphosphate/8-quinolinesulfonyl chloride, followed by the usual coupling procedures by Takaku et al).
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D003485:Cyanates; D017953:Isocyanates; D009841:Oligonucleotides / Q000138:chemical synthesis*; D009843:Oligoribonucleotides / Q000138:chemical synthesis*
chemical_list: D003485:Cyanates; D017953:Isocyanates; D009841:Oligonucleotides; D009843:Oligoribonucleotides; C025319:phenyl isocyanate