title: Chemical synthesis of 2'-deoxyoligonucleotides containing 5-fluoro-2'-deoxycytidine.
abstract: 2'-Deoxyoligonucleotides with 5-fluorocytosine residues incorporated at specific positions of the nucleotide sequence are tools of great potential in the study of the catalytic mechanism by which DNA cytosine methyltransferases methylate the 5-position of DNA cytosine residues in specific sequence contexts. Chemical synthesis of such oligonucleotides is described. Two alternative approaches have been developed, one of which proceeds via a fully protected phosphoramidite of 5-fluoro-4-methylmercapto-2'-deoxyuridine 2, the other via a fully protected phosphoramidite of 5-fluoro-2'-deoxycytidine 3. Either building block can be used in automated oligonucleotide synthesis applying standard elongation cycles and deprotection procedures exclusively. The methylmercapto function of 2 is replaced by an amino group in the final ammonia treatment used for cleavage from support and base deprotection.
authors.affiliation: Institut für Bioorganische Chemie, Humboldt-Universität zu Berlin, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Schmidt
authors.forename: C D
authors.initials: CD
authors.lastname: Pein
authors.forename: H J
authors.initials: HJ
authors.lastname: Fritz
authors.forename: D
authors.initials: D
authors.lastname: Cech
mesh_terms: D001483:Base Sequence; D002851:Chromatography, High Pressure Liquid; D003841:Deoxycytidine / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D009838:Oligodeoxyribonucleotides; D003841:Deoxycytidine; C007746:5-fluoro-2'-deoxycytidine