title: Cleavage of phosphodiesters and of DNA by a bis(guanidinium)naphthol acting as a metal-free anion receptor.
abstract: Phosphoric acid diesters form anions at neutral pH. As a result of charge repulsion they are notoriously resistant to hydrolysis. Nucleophilic attack, however, can be promoted by different types of electrophilic catalysts that bind to the anions and reduce their negative charge density. Although in most cases phosphodiester-cleaving enzymes and synthetic catalysts rely on Lewis acidic metal ions, some exploit the guanidinium residues of arginine as metal-free electrophiles. Here we report that a combination of two guanidines and a hydroxy group yields highly reactive receptor molecules that can attack a broad range of phosphodiester substrates by nucleophilic displacement at phosphorus in a single-turnover mode. Some stable O-phosphates were isolated and characterized further by NMR spectroscopy. The bis(guanidinium)naphthols also cleave plasmid DNA, presumably by a transphosphorylation mechanism.
authors.affiliation: Institut für Organische Chemie und Chemische Biologie, Johann Wolfgang Goethe-Universität Frankfurt, Frankfurt am Main, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Ullrich
authors.forename: Zarghun
authors.initials: Z
authors.lastname: Nazir
authors.forename: Arne
authors.initials: A
authors.lastname: Büsing
authors.forename: Ute
authors.initials: U
authors.lastname: Scheffer
authors.forename: Daniela
authors.initials: D
authors.lastname: Wirth
authors.forename: Jan W
authors.initials: JW
authors.lastname: Bats
authors.forename: Gerd
authors.initials: G
authors.lastname: Dürner
authors.forename: Michael W
authors.initials: MW
authors.lastname: Göbel
mesh_terms: D000838:Anions; D018360:Crystallography, X-Ray; D004247:DNA / Q000737:chemistry*; D019791:Guanidine / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009284:Naphthols / Q000737:chemistry* / Q000494:pharmacology; D010755:Organophosphates / Q000737:chemistry*; D010766:Phosphorylation
chemical_list: D000838:Anions; D009284:Naphthols; D010755:Organophosphates; D004247:DNA; D019791:Guanidine