title: 3'-Azido-3',5'-dideoxythymidine-5'-methylphosphonic acid diphosphate: synthesis and HIV-1 reverse transcriptase inhibition.
abstract: 3'-Azido-3'-deoxythymidine-5'-phosphonate was synthesized by a five-step reaction sequence. The 5'-phosphonate was inactive against HIV-1 in MT4 cells. The absence of activity against HIV-1 was at least partially explained by demonstrating that the Km value for the 5'-deoxy-5'-methylphosphonic acid diphosphate analog with HIV-1 reverse transcriptase (RT) was 320-fold greater than the Km value for 3'-azido-3'- deoxythymidine-5'-triphosphate (AZTTP), and the kcat value for the 5'-deoxy-5'-methylphosphonic acid diphosphate analog was one-seventh the value for AZTTP. These differences in kinetic constants were due to a change in the rate-determining step from dissociation of the RT chain-terminated template-primer complex to the catalytic step. Thus, substitution of a methylene group for the 5'-oxygen atom of AZTTP resulted in an 1800-fold reduction in the rate constant for RT-catalyzed phosphodiester bond formation.
authors.affiliation: Division of Organic Chemistry, Burroughs Wellcome Co., Research Triangle Park, North Carolina 27709.
authors.forename: G A
authors.initials: GA
authors.lastname: Freeman
authors.forename: J L
authors.initials: JL
authors.lastname: Rideout
authors.forename: W H
authors.initials: WH
authors.lastname: Miller
authors.forename: J E
authors.initials: JE
authors.lastname: Reardon
mesh_terms: D000998:Antiviral Agents / Q000138:chemical synthesis* / Q000494:pharmacology; D001483:Base Sequence; D054306:Dideoxynucleotides; D054303:HIV Reverse Transcriptase; D015497:HIV-1 / Q000187:drug effects / Q000201:enzymology*; D007700:Kinetics; D008969:Molecular Sequence Data; D015394:Molecular Structure; D012194:RNA-Directed DNA Polymerase / Q000378:metabolism; D018894:Reverse Transcriptase Inhibitors; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D013942:Thymine Nucleotides / Q000494:pharmacology; D015215:Zidovudine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology
chemical_list: D000998:Antiviral Agents; D054306:Dideoxynucleotides; D018894:Reverse Transcriptase Inhibitors; D013942:Thymine Nucleotides; C076203:3'-azido-3',5'-dideoxythymidine-5'-methylphosphonic acid diphosphate; D015215:Zidovudine; C052873:zidovudine triphosphate; D054303:HIV Reverse Transcriptase; D012194:RNA-Directed DNA Polymerase