title: A conformationally preorganized universal solid support for efficient oligonucleotide synthesis.
abstract: A novel, conformationally preorganized nonnucleosidic universal solid support for oligonucleotide synthesis was developed. The solid support featured two chemically equivalent hydroxy groups locked in syn-periplanar orientation and orthogonally protected with 4,4'-dimethoxytrityl and acetyl groups. The solid support was extensively tested in the preparation of oligonucleotides and their phosphorothioate analogues containing 2'-deoxy, 2'-O-methyl, and 2'-O-methoxyethylnucleoside residues at the 3'-terminus. Upon completion of oligonucleotide chain assembly, the support-bound oligonucleotide material was treated with concentrated ammonium hydroxide, which removed the O-acetyl protection. The deprotected hydroxy group then effected the transesterification of a phosphate linkage between the solid support and the 3'-terminal nucleoside residue to result in a facile release of the oligonucleotide to solution. The kinetics of the release process was studied in a continuous flow of concentrated aqueous ammonium hydroxide at a temperature of 300.15 K. Optimal conditions for the release of oligonucleotides depending on the chemistry of the backbone and 3'-terminal nucleoside residue were formulated.
authors.affiliation: Department of Medicinal Chemistry, Isis Pharmaceuticals, 2292 Faraday Avenue, Carlsbad, CA 92008, USA. aguzaev@isisph.com
authors.forename: Andrei P
authors.initials: AP
authors.lastname: Guzaev
authors.forename: Muthiah
authors.initials: M
authors.lastname: Manoharan
mesh_terms: D000438:Alcohols / Q000737:chemistry; D064753:Ammonium Hydroxide; D002625:Chemistry, Organic / Q000379:methods; D006878:Hydroxides / Q000737:chemistry; D008968:Molecular Conformation; D009705:Nucleosides / Q000737:chemistry*; D009841:Oligonucleotides / Q000138:chemical synthesis*; D010755:Organophosphates / Q000737:chemistry; D009943:Organophosphorus Compounds / Q000737:chemistry; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
chemical_list: D000438:Alcohols; D006878:Hydroxides; D009705:Nucleosides; D009841:Oligonucleotides; D010755:Organophosphates; D009943:Organophosphorus Compounds; C434331:phosphoramidite; D064753:Ammonium Hydroxide