title: Synthesis of Rp and Sp [alpha-18O]ADP from Sp and Rp beta-cyanoethyl-adenosine 5'[1-thiodiphosphate].
abstract: The reaction of adenosine 5'[1-thio-2-cyanoethyl diphosphate], beta-cyanoethyl-ADP alpha S, with cyanogen bromide in aqueous solution near neutrality leads to the formation of adenosine 5'-[2-cyanoethyl diphosphate], beta-cyanoethyl-ADP, in good yield. Reaction of Rp or Sp beta-cyanoethyl-ADP alpha S in H218O produces Sp or Rp beta-cyanoethyl-[alpha-18O]ADP, respectively, with inversion of configuration. Removal of the cyanoethyl groups in KOH produces Sp or Rp [alpha-18O]ADP. Desulfurization of chiral phosphorothioates by reaction with cyanogen bromide in H218O or H217O or of chiral [17O] or [18O] phosphorothioates in water appears to be a convenient method for synthesizing chiral phosphates for use in a variety of investigations of the mechanisms of enzymatic cleavage of P-O bonds.
mesh_terms: D000244:Adenosine Diphosphate / Q000031:analogs & derivatives* / Q000138:chemical synthesis*; D007202:Indicators and Reagents; D007536:Isomerism; D007553:Isotope Labeling / Q000379:methods; D009682:Magnetic Resonance Spectroscopy; D010103:Oxygen Isotopes; D013873:Thionucleotides / Q000138:chemical synthesis*
chemical_list: D007202:Indicators and Reagents; D010103:Oxygen Isotopes; D013873:Thionucleotides; D000244:Adenosine Diphosphate; C033591:beta-cyanoethyl-adenosine 5'-(1-thiodiphosphate)