title: Versatile linker chemistry for synthesis of 3'-modified DNA.
abstract: A general method is described for the solid phase supported synthesis of DNA containing 3'-terminal phosphodiesters modified with linkers bearing either amino, thiol, or hydroxyl groups. These products are all made from a common intermediate, obtained by the reaction of trimellitic anhydride chloride with aminopropyl CPG. The anhydride-derivatized support was then reacted with three appropriate bifunctional spacers, giving DMT-protected hydroxyl solid supports bearing the masked functionality as an ester, amide, or thioester. DNA synthesis was then performed, followed by ammonia cleavage and deprotection, giving the hydroxyl-, amino-, or thiol-functionalized DNA 3'-phosphate diesters, respectively. Test mononucleotides synthesized with each of the new supports were identical with control mononucleotides made with 5'-immobilized nucleosides and alkylhydroxyl, alkylamino, and alkylthio phosphoramidites. The new supports were then used to prepare several 3'-modified oligonucleotides, which were characterized by gel electrophoresis, HPLC, and MALDI mass spectroscopy. The amino- and thiol-functionalized DNAs were conjugated with chromophores, and purification of these products was facilitated by use of reversed phase cartridges.
authors.affiliation: Biosearch Technologies Inc., San Rafael, California 94903, USA.
authors.forename: M H
authors.initials: MH
authors.lastname: Lyttle
authors.forename: H
authors.initials: H
authors.lastname: Adams
authors.forename: D
authors.initials: D
authors.lastname: Hudson
authors.forename: R M
authors.initials: RM
authors.lastname: Cook
mesh_terms: D001483:Base Sequence; D002851:Chromatography, High Pressure Liquid; D003432:Cross-Linking Reagents; D004247:DNA / Q000138:chemical synthesis* / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D005452:Fluoresceins / Q000737:chemistry; D005898:Glass; D015394:Molecular Structure; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis / Q000737:chemistry; D010796:Phthalic Anhydrides; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D003432:Cross-Linking Reagents; D005452:Fluoresceins; D009838:Oligodeoxyribonucleotides; D010796:Phthalic Anhydrides; C015559:trimellitic anhydride; D004247:DNA