• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.1086-1088
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• 2004

Betulin, a pentacyclic triterpenoid isolated from the bark of Betula papyrifera. Laboratory synthesized structural analogs were tested for antiviral activities against Epstein-Barr Virus (EBV) by immunofluorescent antiviral assay. Among the several analogs tested, betulin 3,28-diphosphate and uvaol exhibited significant antiviral activities against EBV. The $EC_{50}$ of betulin 3,28-diphosphate and uvaol was found to be $0.6\mu{M}$ and $0.7\mu{M}$ respectively.

• YAKHAK HOEJI
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• v.50 no.2
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• pp.65-69
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• 2006

Novel 4'-hydroxymethyl branched thioapiosyl nucleosides were synthesized in this study. The introduction of hydroxymethyl group in the 4'-position was accomplished by a [3,3]-sigmatropic rearrangement. Thioapiosyl sugar moiety was constructed by sequential ozonolysis, reduction and cyclization. The pyrimidine nucleosidic bases (uracil, 5-fluorouracil, 5-iodouracil, 5-chlorouracil, 5-bromouracil) were efficiently coupled by Vorbruggen glycosyl condensation procedure (per-silyated base and TMSOTf). The antiviral activities of the synthesised compounds were evaluated against the HIV-1, HSV-1, HSV-2 and EMCV 5-Iodouracil 18 showed weak antiviral activity against HSV-1 $(EC_{50}=30.7{\mu}M)$.

• Journal of Integrative Natural Science
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• v.8 no.3
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• pp.153-163
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• 2015

Racemic synthesis of novel 5',5'-difluoro-2'-methyl-apiose nucleoside phosphonic acid analogs was achieved as potent antiviral agents. Phosphonation was performed by direct displacement of triflate intermediate with diethyl (lithiodifluoromethyl) phosphonate to give the corresponding (${\alpha},{\alpha}$-difluoroalkyl) phosphonate. Condensation successfully proceeded from a glycosyl donor with persilylated bases to yield the nucleoside phosphonate analogs. Deprotection of diethyl phosphonates provided the target nucleoside analogs. An antiviral evaluation of the synthesized compounds against various viruses such as HIV, HSV-1, HSV-2 and HCMV revealed that the pyrimidine analogs (cytosine, uracil, and thymine) have weak anti-HIV or HCMV activity.

• Journal of Integrative Natural Science
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• v.8 no.2
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• pp.99-106
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• 2015

Novel 2'(${\beta}$)-fluoro-3'(${\alpha}$)-hydroxy-threose nucleosides (iso-FMAU) as antiviral agents were designed and racemically synthesized from Solketal. Condensation successfully proceeded from a glycosyl donor 9 under $Vorbr{\ddot{u}}ggen$ conditions yielded the nucleoside analogues. Ammonolysis and hydrolysis of isopropylidene protection group gave the desired nucleoside analogues 12, 15, 18, and 19. The antiviral activities of the synthesized compounds were evaluated against the HIV-1, HSV-1, HSV-2 and HCMV. Compound 12 displayed some anti-HCMV activity ($EC_{50}=24.7{\mu}g/ml$) without exhibiting any cytotoxicity up to $100{\mu}M$.

• Microbiology and Biotechnology Letters
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• v.52 no.2
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• pp.105-113
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• 2024

The precise and elaborate regulation of signaling cascades by diverse cytoplasmic and endosomal antiviral sensors is crucial for maintaining immune homeostasis and defending against viral pathogens. Receptors and enzymes that recognize foreign nucleic acids play a pivotal role in inducing antiviral interferon programs, serving as the first line of defense against various DNA and RNA viruses. Recent research has increasingly highlighted the crosstalk between nucleic acid sensors in detecting multiple virus invasions, resulting in amplified antiviral signals and compensating for any missing roles. This review provides an update on recent findings regarding the interplay of RNA sensors for DNA virus recognition.

• Natural Product Sciences
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• v.21 no.4
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• pp.227-230
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• 2015

Chemical investigation of the fermentation broth of a Soft Coral-Derived fungus Pestalotiopsis sp., led to the isolation of a new phthalide derivative, pestalotiolide A (1), three known analogues (2, 3 and 4), along with 5'-O-acetyl uridine (5) first isolated as a natural product. The structure of the new compound (1) was established by comprehensive spectroscopic analysis and chemical methods. Compounds 1 - 4 possessed varying degrees of antiviral activities, which was reported for the first time. Compared to the positive control ribavirin ($IC_{50}=418.0{\mu}M$), pestalotiolide A (1) exhibited significant anti-EV71 activity in vitro, with an $IC_{50}$ value of $27.7{\mu}M$. Furthermore, the preliminary structure-activity relationship of antiviral activities was also discussed.

• Korean Journal of Pharmacognosy
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• v.47 no.2
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• pp.137-142
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• 2016

Enterovirus is a common cause of several severe diseases such as myocarditis, hand-foot-mouth disease, and meningitis in children and adult. There are many try to develop new antiviral drug for direct treatment in virus infection. However, synthetic chemical antiviral drug is not working. To overcome this limitation, we examined plant extracts. The antiviral effect of plant extracts was screened by HeLa cell survival assay in coxsackievirus B3 (CVB3) infection. We observed a strong antiviral effect of Poria cocos extract in a dose-dependent manner (1 mg/ml~0.01 mg/ml). P. cocos extract (1 mg/ml) treatment was dramatically decreased virus protease 2A induced eIF4G-I cleavage and virus capsid protein VP1 production. CVB3 positive and negative strand RNA amplification were significantly reduced in P. cocos extract treatment. P. cocos extract completely blocked early time activation of ERK and AKT activity in CVB3 infection. Taken together these data indicate that the treatment of P. cocos extract strongly inhibit CVB3 replication. Poria cocos extract may possible to developed as a therapeutic agent for enterovirus.

• Journal of Veterinary Science
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• v.21 no.5
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• pp.72.1-72.10
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• 2020

Background: Fenbendazole, a dewormer drug, is used widely in the clinical treatment of parasite infections in animals. Recent studies have shown that fenbendazole has substantial effects on tumor growth, immune responses, and inflammatory responses, suggesting that fenbendazole is a pluripotent drug. Nevertheless, the antiviral effects have not been reported. Fenbendazole can disrupt microtubules, which are essential for multiple viruses infections, suggesting that fenbendazole might have antiviral effects. Objectives: This study examined whether fenbendazole could inhibit bovine herpesvirus 1 (BoHV-1) productive infection in cell cultures. Methods: The effects of fenbendazole on viral production, transcription of the immediate early (IE) genes, viron-associated protein expression, and the cellular signaling PLC-γ1/Akt pathway were assessed using distinct methods. Results: Fenbendazole could inhibit BoHV-1 productive infections significantly in MDBK cells in a dose-dependent manner. A time-of-addition assay indicated that fenbendazole affected both the early and late stages in the virus replication cycles. The transcription of IE genes, including BoHV-1 infected cell protein 0 (bICP0), bICP4, and bICP22, as well as the synthesis of viron-associated proteins, were disrupted differentially by the fenbendazole treatment. The treatment did not affect the cellular signaling pathway of PLC-γ1/Akt, a known cascade playing important roles in virus infection. Conclusions: Overall, fenbendazole has antiviral effects on BoHV-1 replication.

• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.444-450
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• 2022

The effect of coated polyester (PET) textiles with metal oxide, chitosan, and copper ion on the antibacterial and antiviral activities was evaluated to investigate the applicability of multi-coated PET textiles as antiviral materials. Compared to coated PETs with a single agent, multi-coated PETs reduced the loading amount of coating materials as well as the contact time with bacteria for a bacterial cell number of < 10 CFU/mL, which was not detectable with the naked eyes. Metal oxides generate reactive oxygen species (ROS) such as free radicals by a catalytic reaction, and copper ions can promote contact killing by the generation of ROS. Chitosan not only enhanced antibacterial activities due to amine groups, but enabled it to be a template to load copper ions. We observed that multi-coated PET textiles have both antibacterial activities for E. coli and S. aureus and antiviral efficiency of more than 99.9% for influenza A (H1N1) and SARS-CoV-2. The multi-coated PET textiles could also be prepared via a roll-to-roll coating process, which showed high antiviral efficacy, demonstrating its potential use in air filtration and antiviral products such as masks and personal protective equipment.

• Biomolecules & Therapeutics
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• v.23 no.5
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• pp.465-470
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• 2015

Chrysin is a 5,7-dihydroxyflavone and was recently shown to potently inhibit enterovirus 71 (EV71) by suppressing viral 3C protease ($3C^{pro}$ activity. In the current study, we investigated whether chrysin also shows antiviral activity against coxsackievirus B3 (CVB3), which belongs to the same genus (Enterovirus) as EV71, and assessed its ability to prevent the resulting acute pancreatitis and myocarditis. We found that chrysin showed antiviral activity against CVB3 at $10{\mu}M$, but exhibited mild cellular cytotoxicity at $50{\mu}M$, prompting us to synthesize derivatives of chrysin to increase the antiviral activity and reduce its cytotoxicity. Among four 4-substituted benzyl derivatives derived from C(5) benzyl-protected derivatives 7, 9-11 had significant antiviral activity and showed the most potent activity against CVB3 with low cytotoxicity in Vero cells. Intraperitoneal injection of CVB3 in BALB/c mice with $1{\times}10^6TCID_{50}$ (50% tissue culture infective dose) of CVB3 induced acute pancreatitis with ablation of acinar cells and increased serum CXCL1 levels, whereas the daily administration of 9 for 5 days significantly alleviated the pancreatic inflammation and reduced the elevation in serum CXCL1 levels. Collectively, we assessed the anti-CVB3 activities of chrysin and its derivatives, and found that among 4-substituted benzyl derivatives, 9 exhibited the highest activity against CVB3 in vivo, and protected mice from CVB3-induced pancreatic damage, simultaneously lowering serum CXCL1 levels.