title: A rapid and convenient synthesis of poly-thymidylic acid by the modified triester approach.
abstract: By using anhydrous triethylamine-pyridine to selectively remove the cyanoethyl group from the fully protected oligonucleotide, a substantial improvement has been achieved in yields and the rates of condensation by the modified triester approach from the 5' leads to 3' end. The unreacted oligonucleotide containing the 5'-hydroxy group was removed by treatment with bis (triazolyl)-p-chlorophenyl phosphate after each condensation in situ. These modifications, as exemplified by the synthesis of fully protected T12, T18, T24 and T38 in 80%, 77%, 70% and 50% yields respectively, should allow the ready synthesis of polynucleotides of even longer chain lengths by purely chemical methods.
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D004952:Esters; D008722:Methods; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis; D011071:Poly T / Q000138:chemical synthesis*; D011089:Polydeoxyribonucleotides / Q000138:chemical synthesis*
chemical_list: D004952:Esters; D009838:Oligodeoxyribonucleotides; D011089:Polydeoxyribonucleotides; D011071:Poly T