title: The cyclization of arabinosyladenine-5'-phosphorimidazolide.
abstract: When arabinosyladenine-5'-phosphorimidazolide is allowed to decompose in aqueous solution at room temperature and pH 7.2, depending on the buffer, 5-24% is converted to the 2',5'-cyclic phosphate (V).  Although the extent of cyclization is much greater than for adenosine-5'-phosphorimidazolide, cyclization is less efficient than hydrolysis and so would not substantially decrease the efficiency of condensation reactions in aqueous solution.  The significance of this result for prebiotic chemistry is discussed.
authors.affiliation: The Salk Institute for Biological Studies, San Diego, CA 92186-5800, USA.
authors.forename: K
authors.initials: K
authors.lastname: Harada
authors.forename: L E
authors.initials: LE
authors.lastname: Orgel
mesh_terms: D000249:Adenosine Monophosphate / Q000031:analogs & derivatives / Q000737:chemistry; D003500:Cyclization; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D046911:Macromolecular Substances; D009705:Nucleosides / Q000032:analysis / Q000737:chemistry*; D009711:Nucleotides / Q000032:analysis / Q000737:chemistry*; D011108:Polymers / Q000138:chemical synthesis; D013696:Temperature; D013698:Templates, Genetic; D014740:Vidarabine / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D046911:Macromolecular Substances; D009705:Nucleosides; D009711:Nucleotides; D011108:Polymers; C010671:adenosine 5'-phosphoroimidazolide; D000249:Adenosine Monophosphate; D014740:Vidarabine