title: 8-aza-7-deazaadenine and 7-deazaguanine: synthesis and properties of nucleosides and oligonucleotides with nucleobases linked at position-8.
abstract: The 8-aza-7-deazaadenine (pyrazolo[3,4-d]pyrimidin-4-amine) N8-(2'-deoxyribonucleoside) (2) and the 7-deazaguanine (pyrrolo[3,4-d]pyrimidine-2-amin-(3H)-4-one) C8-(2'-deoxyribonucleoside) (4) were synthesized and incorporated in oligonucleotides employing phosphoramidite chemistry. Oligonucleotides carrying compound 2 are able to form base pairs with the four canonical DNA constituents without significant structural discrimination. The nucleoside 4 was obtained from the corresponding ribonucleoside by deoxygenation. Oligonucleotides containing compound 4 showed similar base pairing properties as those with 2'-deoxyisoguanosine.
authors.affiliation: Laboratorium für Organische und Bioorganische Chemie, Institut für Chemie, Universität Osnabrück, Barbarastr. 7, D-49069 Osnabrück, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Seela
authors.forename: H
authors.initials: H
authors.lastname: Debelak
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry*; D020029:Base Pairing; D004247:DNA / Q000737:chemistry; D003853:Deoxyribonucleosides / Q000138:chemical synthesis / Q000737:chemistry*; D003854:Deoxyribonucleotides / Q000138:chemical synthesis / Q000737:chemistry*; D006147:Guanine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry*; D009711:Nucleotides / Q000138:chemical synthesis / Q000737:chemistry*; D009841:Oligonucleotides / Q000138:chemical synthesis / Q000737:chemistry*; D011720:Pyrazoles / Q000138:chemical synthesis / Q000737:chemistry*; D011758:Pyrroles / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: C442440:(pyrazolo(3,4-d)pyrimidin-4-amine) N8-(2'-deoxyribonucleoside); C442441:(pyrrolo(3,4-d)pyrimidine-2-amin-(3H)-4-one) C8-(2'-deoxyribonucleoside); D003853:Deoxyribonucleosides; D003854:Deoxyribonucleotides; D009711:Nucleotides; D009841:Oligonucleotides; D011720:Pyrazoles; D011758:Pyrroles; C414764:8-aza-7-deazaadenine; D006147:Guanine; D004247:DNA; C066856:7-deazaguanine; D000225:Adenine