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Frontiers in Chemistry 2019A series of -((3-phenyl-1-(phenylsulfonyl)-1-pyrazol-4-yl)methyl)anilines and , structurally related to previously synthesized and tested...
A series of -((3-phenyl-1-(phenylsulfonyl)-1-pyrazol-4-yl)methyl)anilines and , structurally related to previously synthesized and tested (-(1,3-diphenyl-1-pyrazol-4-yl)methyl)anilines (), were designed and synthesized. The new derivatives were evaluated in cell-based assays for their cytotoxicity and antiviral activity against a large panel of RNA and DNA viruses of public health significance. Generally, the tested compounds did not display cytotoxicity toward the cell lines used. The majority of derivatives - were able to interfered with YFV and RSV replication in the micromolar range showing a marked improvement in potency and selectivity with respect to the reference inhibitors 6-azauridine and ribavirin, respectively. The introduction of a -methoxy substituent on the phenylsulfonyl group (compounds ) completely abolished the anti-RSV activity and reduced or eliminated the potency against YFV. On the contrary, several -methoxy analogs were able to interfere with BVDV replication with a comparable (, and ) or better ( and ) potency than the reference inhibitor, ribavirin. Compound , selected for time of addition experiments on BHK-21 cell cultures infected with YFV, achieved the highest reduction of virus titer when added 2 h post infection and maintained up to 4 h post infection.
PubMed: 31024899
DOI: 10.3389/fchem.2019.00214 -
Antiviral Research Sep 2017Cell culture antiviral experiments were conducted in order to understand the relationship between percentage data generated by plaque reduction (PR) and logarithmic data... (Comparative Study)
Comparative Study
Cell culture antiviral experiments were conducted in order to understand the relationship between percentage data generated by plaque reduction (PR) and logarithmic data derived by virus yield reduction (VYR) assays, using three-dimensional MacSynergy II software. The relationship between percentage and logarithmic data has not been investigated previously. Interpretation of drug-drug interactions is based on a Volume of Synergy (VS) calculation, which can be positive (synergy), negative (antagonistic), or neutral (no or minimal interaction). Interactions of two known inhibitors of vaccinia virus replication, cidofovir and 6-azauridine, used in combination by PR assay yielded a VS value of 265, indicative of strong synergy. By VYR, the VS value was only 37, or weak synergy using the same criterion, even though profound log reductions in virus titer occurred at multiple drug combinations. These results confirm that the differences in VS values is dependent of the measurement scale, and not that the degree of synergy differed between the assays. We propose that for logarithmic data, the calculated VS values will be lower for significant synergy and antagonism and that volumes of >10 μMlog PFU/ml (or other units such as μMlog genomic equivalents/ml or μMlog copies/ml) and <-10 μMlog PFU/ml are likely to be indicative of strong synergy and strong antagonism, respectively. Data presented here show that the interaction of cidofovir and 6-azauridine was strongly synergistic in vitro.
Topics: Animals; Antiviral Agents; Azauridine; Chlorocebus aethiops; Cidofovir; Cytosine; Data Accuracy; Data Interpretation, Statistical; Drug Interactions; Drug Synergism; Humans; Microbial Sensitivity Tests; Organophosphonates; Software; Vaccinia virus; Vero Cells; Viral Plaque Assay; Virus Replication
PubMed: 28676302
DOI: 10.1016/j.antiviral.2017.06.022 -
Journal of Virological Methods Aug 2017Studies were conducted to determine the performance of four dyes in assessing antiviral activities of compounds against three RNA viruses with differing cytopathogenic...
Studies were conducted to determine the performance of four dyes in assessing antiviral activities of compounds against three RNA viruses with differing cytopathogenic properties. Dyes included alamarBlue measured by absorbance (ALB-A) and fluorescence (ALB-F), neutral red (NR), Viral ToxGlo™ (VTG), and WST-1. Viruses were chikungunya, dengue type 2, and Junin, which generally cause 100, 80-90, and 50% maximal cytopathic effect (CPE), respectively, in Vero or Vero 76 cells Compounds evaluated were 6-azauridine, BCX-4430, 3-deazaguanine, EICAR, favipiravir, infergen, mycophenolic acid (MPA), ribavirin, and tiazofurin. The 50% virus-inhibitory (EC) values for each inhibitor and virus combination did not vary significantly based on the dye used. However, dyes varied in distinguishing the vitality of virus-infected cultures when not all cells were killed by virus infection. For example, VTG uptake into dengue-infected cells was nearly 50% when visual examination showed only 10-20% cell survival. ALB-A measured infected cell viability differently than ALB-F as follows: 16% versus 32% (dengue-infected), respectively, and 51% versus 72% (Junin-infected), respectively. Cytotoxicity (CC) assays with dyes in uninfected proliferating cells produced similar CC values for EICAR (1.5-8.9μM) and MPA (0.8-2.5μM). 6-Azauridine toxicity was 6.1-17.5μM with NR, VTG, and WST-1, compared to 48-92μM with ALB-A and ALB-F (P<0.001). Curiously, the CC values for 3-deazaguanine were 83-93μM with ALB-F versus 2.4-7.0μM with all other dyes including ALB-A (P<0.001). Overall, ALB minimized the toxicities detected with these two inhibitors. Because the choice of dyes affected CC values, this impacted on the resulting in vitro selectivity indexes (calculated as CC/EC ratio).
Topics: Animals; Antiviral Agents; Cell Survival; Chikungunya virus; Chlorocebus aethiops; Coloring Agents; Cytopathogenic Effect, Viral; Dengue Virus; Junin virus; Oxazines; RNA Viruses; Vero Cells; Virus Replication; Viruses; Xanthenes
PubMed: 28359770
DOI: 10.1016/j.jviromet.2017.03.012 -
Organic & Biomolecular Chemistry Jan 2017To display favorable fluorescent properties, the non-emissive native nucleosides need to be modified. Here we present a motif that relies on conjugating 5-membered...
To display favorable fluorescent properties, the non-emissive native nucleosides need to be modified. Here we present a motif that relies on conjugating 5-membered aromatic heterocycles (e.g., thiophene) to a 6-azapyrimidine (1,2,4-triazine) core. Synthetic accessibility and desirable photophysical properties make these nucleosides attractive candidates for enzymatic incorporation and biochemical assays. While 6-azauridine triphosphate is known to be poorly tolerated by polymerases in RNA synthesis, we illustrate that conjugating a thiophene ring at position 5 overcomes such limitations, facilitating its T7 RNA polymerase-mediated in vitro transcription incorporation into RNA constructs. We further show that the modified transcripts can be ligated to longer oligonucleotides to form singly modified RNAs, as illustrated for an A-site hairpin model RNA construct, which was employed to visualize aminoglycoside antibiotics binding.
Topics: Azauridine; DNA-Directed RNA Polymerases; Fluorescence; RNA; Viral Proteins
PubMed: 27981333
DOI: 10.1039/c6ob02080a -
Retrovirology Mar 2016BST-2 is an interferon-induced host restriction factor that inhibits the release of diverse mammalian enveloped viruses from infected cells by physically trapping the...
BACKGROUD
BST-2 is an interferon-induced host restriction factor that inhibits the release of diverse mammalian enveloped viruses from infected cells by physically trapping the newly formed virions onto the host cell surface. Human Immunodeficiency Virus-1 (HIV-1) encodes an accessory protein Vpu that antagonizes BST-2 by down-regulating BST-2 from the cell surface.
RESULTS
Using a cell-based ELISA screening system, we have discovered a lead compound, 2-thio-6-azauridine, that restores cell surface BST-2 level in the presence of Vpu. This compound has no effect on the expression of BST-2 and Vpu, but inhibits Vpu-mediated BST-2 down-regulation and exerts no effect on Vpu-induced down-regulation of CD4 or KSHV K5 protein induced BST-2 down-regulation. 2-thio-6-azauridine suppresses HIV-1 production in a BST-2-dependent manner. Further results indicate that 2-thio-6-azauridine does not interrupt the interaction of BST-2 with Vpu and β-TrCP2, but decreases BST-2 ubiquitination.
CONCLUSION
Our study demonstrates the feasibility of using small molecules to target Vpu function and sensitize wild type HIV-1 to BST-2-mediated host restriction.
Topics: Anti-HIV Agents; Antigens, CD; Azauridine; Drug Evaluation, Preclinical; GPI-Linked Proteins; HIV-1; HeLa Cells; Human Immunodeficiency Virus Proteins; Humans; Thiouridine; Viral Regulatory and Accessory Proteins
PubMed: 26935098
DOI: 10.1186/s12977-016-0247-z -
Organic Letters Oct 2014A family of extended 5-modified-6-aza-uridines was obtained via Suzuki coupling reactions with a common brominated precursor. Extending the conjugated-6-aza-uridines...
A family of extended 5-modified-6-aza-uridines was obtained via Suzuki coupling reactions with a common brominated precursor. Extending the conjugated-6-aza-uridines with substituted aryl rings increases the push-pull interactions yielding enhanced bathochromic shifts and solvatochromism compared to the parent nucleosides. For example, the methoxy substituted derivative 1d displays λmax abs around 375 nm, with visible emission maxima at 486 nm (Φ = 0.74) and 525 nm (Φ = 0.02) in dioxane and water, respectively.
Topics: Azauridine; Crystallography, X-Ray; Fluorescent Dyes; Molecular Conformation; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Nucleosides
PubMed: 25285451
DOI: 10.1021/ol502435d