Antiviral activity against vesicular stomatitis

The hot water extracts of bulbs and leaves of Haemanthus albiflos had strong antiviral activity against Poliovirus 1, Herpes simplex 1 virus. Vesicular stomatitis vims and simian Rotavirus SA11 (100, 101). The bulbs of this species also showed strong antiviral activity against Moloney murine leukemia virus and HIV(i02). 

The trienamide onnamide A (43) is a metabolite isolated from the marine sponge Theonella sp. found in Okinawan waters [84]. It belongs to the pederin family like mycalamides and theopederins [85], and shows a potent antiviral activity against herpes simplex virus type-1, vesicular stomatitis virus, and coronavirus A-59. The complete determination of the structure was carried out during the total synthesis of onnamide A (43)... 

A lyophylisate of the expressed sap of . purpurea in cultures of mice L-cells (clone 929) at a concentration of 10 ig/ml to 100 Llg/ml exhibited no direct antiviral activity against encephalomyocarditis virus (EMC virus) or vesicular-stomatitis-virus (VSV). An antiviral effect was only observed when the sap was added together with DEAR dextran. DEAE dextran itself showed no effect. The authors concluded an interferon-like activity [145]. By the colorimetric assay according to Finter and by the Plaque-Reduction-Assay it could be shown, that mice L-929 cells or HeLa cells became resistant for 24 h against influenza-, herpes- and vesicular-stomatitis-virus by 50-80%, when the cells were pretreated 4-6 h with 20 ig/ml of an . purpurea expressed sap preparation. Together with hyaluronidase, no effect was observed. The active component could not be inactivated by heat (60-80 C) [146]. 

E. purpurea extracts have shown indirect antiviral activity against encephalomyocardi-tis, vesicular stomatitis, influenza, herpes, and poliovirus described as interferon-like. The 70% ethanolic extract of E. pallida and the n-hexane extract of E. purpurea inhibited HSV-1 in vitro at MIC 0.026 mg/mL and 0.12mg/mL, respectively. The alkamide constituents of the extracts may be behind... 

The first synthesis of racemic [9-(2,3-dihydroxypropyl)adenine] DHPA, C H N O was reported in 1965 (59), and the synthesis of the (R)- and (5)-enantiomers of DHPA was reported later (60). Subsequendy (5)-DHPA [54262-83-8] (29) was shown to be active against a broad range of DNA and RNA vimses including vaccinia, HSV-1, HSV-2, measles, and vesicular stomatitis viruses. The racemic mixture, (R,3)-DHPA [55904-02-4] was almost as active as the (3)-enantiomer. However, the (R)-isomer of DHPA was inactive as an antiviral agent. 

Thia-8-oxoguanosine 5-amino-3-p-D-ribofuranosylthiazolo[4,5- pyrimidine-2,7(3fJ,6.Ff)-dione, 59 [122970 40-5] synthesized by ICN Pharmaceuticals, (138) has shown broad-spectmm antiviral activity. 7-Thia-8-oxoguanosine, C10H12N4O6S, is highly active in mice and rats against Semliki Forest, San Angelo, benzi, rat corona, and encephalomyocarditis viruses when administered intraperitoneaUy before exposure to the vims (139). The compound was moderately effective in mice infected intraperitoneaUy with HSV-2 or intranasaUy with vesicular stomatitis vims. The mode of antiviral action of (59) in vivo may be due in part to the induction of interferon Ot (138). 

Evidence of antiviral effects has especially been shown for St. John s Wort [2,3,10], Plant preparations with different chemical composition have been assayed against various viruses and both, hypericin and pseudohypericin, were found to be particularly effective as virucidal agents. The two compounds have been shown to be active against a broad range of viruses and retroviruses, such as herpes simplex virus types I and II, vesicular stomatitis and influenza viruses, cytomegalovyrus and human immunodeficiency virus-1 [2,3,10,91,92]. 

Type I (IFN-a/P) and type II (IFN-y) IFNs are major lines of defense against viral infection. IFNs mediate direct antiviral effector mechanisms that inhibit multiple steps of viral replication (Samuel 1991 Vilcek and Sen 1996). For example, 2, 5 -oligoadenylate synthetase (2, 5 -OAS) activates ribonuclease L, which degrades mRNA and limits the accumulation of viral transcripts. Protein kinase R blocks translation of viral transcripts by phosphorylating translation initiation factor eIF-2. Mx proteins block influenza, vesicular stomatitis virus, and herpes simplex virus replication by an unknown mechanism. 

The antiviral activity of a triterpene saponin isolated from angallis arvensis, was studied in vitro against several vimses including HSV-1, adenovirus type 6, vaccinia, vesicular stomatitis and poliovirus (Amoros et al. 1987). The drug was found to inhibit the replication of HSV-1 and poliovirus type 2 as shown by inhibition of cytopathic effect and reduction of virus production. The action was not due to a virucidal effect but might involve inhibition of virus-host cell attachment. Single cycle experiments indicated that saponins interfered with both early and late events of herpes virus replication (Amoros et al. 1987). 

Significant antiviral ejfectivity was shown in vitro for titanocene dichloride (I) against numerous DNA and RNA viruses in the extracellular phase Typical examples of viruses, which were inhibited by direct contact with I and lost infectivity up to 100%, were orthopoxvirus (vaccinia) and herpes virus (pseudorabies) as DNA viruses, and rhabdovirus (vesicular stomatitis), paramyxovirus (Newcastle disease) and diverse orthomyxoviruses (e.g. influenza A and B) as RNA viruses. A comparable antiviral effect against herpes viruses was detectable after application of the ferricenium salt whereas, on the other hand, vanadocene dichloride (11) and molybdenocene dichloride (V) failed to show antiviral activity under the same experimental conditions. 

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