title: Synthesis, characterization, and biological activity of a new potent class of anti-HIV agents, the peroxoniobium-substituted heteropolytungstates.
abstract: The mono- and trisubstituted peroxyniobium polyoxotungstates of formulas [(CH3)3NH]7[Si-(NbO2)3W9O37], Cs7[Si(NbO2)3W9O37], alpha-K5[Si(NbO2)W11O39] and alpha-[(CH3)3NH]5[Si(NbO2)-W11O39], have been prepared, purified, and characterized spectroscopically by 29Si NMR, 183W NMR, and IR. The presence of peroxo groups was verified by the yellow color of the product and quantified by iodometric titration. The potency of both the complexes and the precursor complexes was evaluated in human peripheral blood mononuclear cells (PBMC) acutely infected with human immunodeficiency virus type 1 (HIV-1). Hexaniobate (K7H[Nb6O19]) was the least effective with a median effective concentration (EC50) of > 100 microM, while Cs7[Si(NbO2)3W9O37] was one of the most effective compounds with an EC50 of 1.0 microM. None of the compounds were toxic to uninfected PBMC with the exception of alpha-K8[SiW11O39], which had a median inhibitory concentration (IC50) of 79 microM. The potency and selectivity of the complexes against HIV-1 reverse transcriptase was also evaluated and shown to be quite high (IC50 values from 0.03 to 0.06 microM). The trimethylammonium salts of the complexes were tested for their ability to inhibit the interaction between gp120 and CD4 using a cell-free system. The complex [(CH3)3NH]7[Si(NbO2)3W9O37] inhibited this interaction by 70% at 25 microM.
authors.affiliation: Department of Chemistry, Emory University, Atlanta, Georgia 30322.
authors.forename: G S
authors.initials: GS
authors.lastname: Kim
authors.forename: D A
authors.initials: DA
authors.lastname: Judd
authors.forename: C L
authors.initials: CL
authors.lastname: Hill
authors.forename: R F
authors.initials: RF
authors.lastname: Schinazi
mesh_terms: D000998:Antiviral Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D002478:Cells, Cultured; D054303:HIV Reverse Transcriptase; D015497:HIV-1 / Q000187:drug effects; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000187:drug effects; D009556:Niobium; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D018894:Reverse Transcriptase Inhibitors; D017655:Silicon Compounds / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D013329:Structure-Activity Relationship; D014414:Tungsten; D017973:Tungsten Compounds / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000998:Antiviral Agents; D009942:Organometallic Compounds; D018894:Reverse Transcriptase Inhibitors; D017655:Silicon Compounds; D017973:Tungsten Compounds; D009556:Niobium; C086546:cesium silicon triperoxyniobium polyoxotungstate; D054303:HIV Reverse Transcriptase; D014414:Tungsten