title: Biologically relevant phosphoranes: structural characterization of a nucleotidyl phosphorane.
abstract: The first successful crystal structures of biorelevant nucleoside and carbohydrate-based phosphoranes are reported. Employing thymidine, a nucleotidyl phosphorane was synthesized in 90% yield and was shown by X-ray analysis to possess a trigonal bipyramidal geometry. With the use of 1,2-O-isopropylidene-alpha-d-glucofuranose, a carbohydrate-based phosphorane was formed and similarly found to have a trigonal bipyramidal geometry. NMR studies demonstrated the existence of isomerism in solution associated with the nucleotidyl phosphorane and rapid exchange for the carbohydrate-based phosphorane. The geometrical representations reported here are expected to have significant applications associated with active site mechanisms of phosphoryl transfer enzymes, for example, in DNA, RNA, c-AMP, and others.
authors.affiliation: Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003-9336, USA.
authors.forename: Natalya V
authors.initials: NV
authors.lastname: Timosheva
authors.forename: A
authors.initials: A
authors.lastname: Chandrasekaran
authors.forename: Robert R
authors.initials: RR
authors.lastname: Holmes
mesh_terms: D018360:Crystallography, X-Ray; D008958:Models, Molecular; D015394:Molecular Structure; D009711:Nucleotides / Q000737:chemistry*; D010753:Phosphoranes / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D009711:Nucleotides; D010753:Phosphoranes