title: Syntheses and configurational analyses of thymidine 4-nitrophenyl [17O,18O]phosphates and the stereochemical course of a reaction catalyzed by bovine pancreatic deoxyribonuclease I.
abstract: The syntheses of both diastereomers of thymidine 3'-(4-nitrophenyl [17O,18O]phosphate) [( 17O,18O]TpNP) and of thymidine 5'-(4-nitrophenyl [17O,18O]phosphate) [( 17O,18O]NPpT) and the Rp diastereomer of thymidine 3'-(4-nitrophenyl [17O,18O]phosphate) 5'-(4-nitrophenyl phosphate) [( 17O,18O]NPpTpNP) are described. The absolute configurations of the chiral phosphorus atoms have been determined unambiguously by 31P and 17O NMR spectroscopy. The Rp diastereomer of [17O,18O]NPpTpNP was hydrolyzed in the presence of bovine pancreatic deoxyribonuclease I to yield the Rp diastereomer of thymidine 3'-[16O,17O,18O]-phosphate 5'-(4-nitrophenyl phosphate), demonstrating that the enzyme-catalyzed reaction occurs by a mechanism in which a single displacement reaction occurs at the chiral phosphorus atom.
mesh_terms: D000818:Animals; D002417:Cattle; D003850:Deoxyribonuclease I / Q000378:metabolism*; D007202:Indicators and Reagents; D007553:Isotope Labeling / Q000379:methods; D009682:Magnetic Resonance Spectroscopy; D010103:Oxygen Isotopes; D010179:Pancreas / Q000201:enzymology; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D013938:Thymidine Monophosphate / Q000031:analogs & derivatives / Q000138:chemical synthesis*; D013942:Thymine Nucleotides / Q000138:chemical synthesis*
chemical_list: D007202:Indicators and Reagents; D010103:Oxygen Isotopes; D013942:Thymine Nucleotides; C043805:4-nitrophenyl 3'-thymidylate; C032579:thymidine 5'-4-nitrophenyl phosphate; D013938:Thymidine Monophosphate; D003850:Deoxyribonuclease I