title: Adenine derivatives as phosphate-activating groups for the regioselective formation of 3',5'-linked oligoadenylates on montmorillonite:  possible phosphate-activating groups for the prebiotic synthesis of RNA.
abstract: Methyladenine and adenine N-phosphoryl derivatives of adenosine 5'-monophosphate (5'-AMP) and uridine 5'-monophosphate (5'-UMP) are synthesized, and their structures are elucidated. The oligomerization reactions of the adenine derivatives of 5'-phosphoramidates of adenosine on montmorillonite are investigated. 1-Methyladenine and 3-methyladenine derivatives on montmorillonite yielded oligoadenylates as long as undecamer, and the 2-methyladenine and adenine derivatives on montmorillonite yielded oligomers up to hexamers and pentamers, respectively. The 1-methyladenine derivative yielded linear, cyclic, and A5'ppA-derived oligonucleotides with a regioselectivity for the 3',5'-phosphodiester linkages averaging 84%. The effect of pKa and amine structure of phosphate-activating groups on the montmorillonite-catalyzed oligomerization of the 5'-phosphoramidate of adenosine are discussed. The binding and reaction of methyladenine and adenine N-phosphoryl derivatives of adenosine are described.
authors.affiliation: Department of Chemistry, Rensselaer Polytechnic Institute, Troy, New York 12180-3590, USA.
authors.forename: K J
authors.initials: KJ
authors.lastname: Prabahar
authors.forename: J P
authors.initials: JP
authors.lastname: Ferris
mesh_terms: D015761:4-Aminopyridine / Q000737:chemistry; D000225:Adenine / Q000031:analogs & derivatives / Q000737:chemistry; D000241:Adenosine / Q000031:analogs & derivatives / Q000493:pharmacokinetics; D000249:Adenosine Monophosphate / Q000031:analogs & derivatives / Q000737:chemistry*; D001546:Bentonite / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D019143:Evolution, Molecular; D009682:Magnetic Resonance Spectroscopy; D009841:Oligonucleotides / Q000138:chemical synthesis*; D000069497:Origin of Life; D012313:RNA / Q000138:chemical synthesis*; D014542:Uridine Monophosphate / Q000031:analogs & derivatives / Q000737:chemistry
chemical_list: D009841:Oligonucleotides; D001546:Bentonite; D000249:Adenosine Monophosphate; C008407:1-methyladenine; D012313:RNA; D015761:4-Aminopyridine; D014542:Uridine Monophosphate; D000225:Adenine; D000241:Adenosine