title: D- and L-2',3'-didehydro-2',3'-dideoxy-3'-fluoro-carbocyclic nucleosides: synthesis, anti-HIV activity and mechanism of resistance.
abstract: Introducing 2'-fluoro substitution on the 2',3'-double bond in carbocyclic nucleosides has provided biologically interesting compounds with potent anti-HIV activity. As an extension of our previous works in the discovery of anti-HIV agents, D- and L-2',3'-unsaturated 3'-fluoro carbocyclic nucleosides were synthesized and evaluated against HIV-1 in human peripheral blood mononuclear (PBM) cells. Among the synthesized L-series nucleosides, compounds 18, 19, 26 and 28 exhibited moderate antiviral activity (EC50 7.1 microM, 6.4 microM, 10.3 microM, and 20.7 microM, respectively), while among the D-series, the guanosine analogue (35, D-3'-F-C-d4G) exhibited the most potent anti-HIV activity (EC50 0.4 microM, EC90 2.8 microM). However, the guanosine analogue 35 was cross-resistant to the lamivudine-resistant variants (HIV-1M184V). Molecular modeling studies suggest that hydrophobic interaction as well as hydrogen-bonding stabilize the binding of compound 35 in the active site of wild type HIV reverse transcriptase (HIV-RT). In the case of L-nucleosides, these two effects are opposite which results in a loss of binding affinity. According to the molecular modeling studies, cross-resistance of D-3'-F-C-d4G (35) to M184V mutant may be caused by the realignment of the primer and template in the HIV-RTM184V interaction, which destabilizes the RT-inhibitor triphosphate complex, resulting in a significant reduction in anti-HIV activity of the D-guanine derivative 35.
authors: College of Pharmacy, The University of Georgia, Athens, Georgia 30602, USA.
authors: Jianing
authors: J
authors: Wang
authors: Yunho
authors: Y
authors: Jin
authors: Kimberly L
authors: KL
authors: Rapp
authors: Raymond F
authors: RF
authors: Schinazi
authors: Chung K
authors: CK
authors: Chu
mesh_terms: D019380:Anti-HIV Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D002478:Cells, Cultured; D024882:Drug Resistance, Viral; D006147:Guanine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D054303:HIV Reverse Transcriptase / Q000737:chemistry / Q000235:genetics; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics; D006801:Humans; D006860:Hydrogen Bonding; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000821:virology; D008958:Models, Molecular; D009154:Mutation; D009705:Nucleosides / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D018894:Reverse Transcriptase Inhibitors / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
chemical_list: C520344:9-(2,3-dideoxy-2,3-didehydro-3-fluoro-6-hydroxymethylcyclopent-2-enyl)guanine; D019380:Anti-HIV Agents; D009705:Nucleosides; D018894:Reverse Transcriptase Inhibitors; D006147:Guanine; D054303:HIV Reverse Transcriptase