| Literature DB >> 6878043 |
P S Miller, C H Agris, M Blandin, A Murakami, P M Reddy, S A Spitz, P O Ts'o.
Abstract
Methylphosphonic dichloride was used to prepare protected deoxyribonucleoside 3'-methylphosphonate beta-cyanoethyl esters, d-[(MeO)2Tr]NpCNEt, and protected oligonucleoside methylphosphonates in solution. Reaction of d-[(MeO)2Tr]N with methylphosphonic dichloride gives d-[(MeO)2Tr]NpCl. The phosphonylation and subsequent esterification or condensation reactions are each complete within 60 min. The products are readily purified by "flash chromatography" on silica gel columns. d-[(MeO)2Tr]NpCl, or its tetrazole derivative, d-[(MeO)2Tr]Nptet, were tested as intermediates for the synthesis of oligothymidine methylphosphonates on a silica gel polymer support. The average yield per coupling step was 76% and did not increase with addition of more d-[(MeO)2Tr]TpCl. The formation of (5'-5') linked thymidine dimers indicated that the thymidine monomers are clustered closely together on the support. When N is ibuG, the yield for the coupling step on the support is very low. This may be due to steric hindrance of the 3'-phosphonate group by the N-2 isobutryl protecting group.Entities:
Mesh:
Substances:
Year: 1983 PMID: 6878043 PMCID: PMC326248 DOI: 10.1093/nar/11.15.5189
Source DB: PubMed Journal: Nucleic Acids Res ISSN: 0305-1048 Impact factor: 16.971