Antiviral activity of betulin, betulinic and betulonic acids against some enveloped and non-enveloped viruses.

Antiviral properties of betulin, betulinic and betulonic acids were investigated in cell cultures infected with herpes simplex type I, influenza FPV/Rostock and ECHO 6 viruses. All studied triterpenes were active against herpes simplex virus. Betulin and especially betulinic acid also suppressed ECHO 6 virus reproduction.

[Experimental microbiological research on instrument and denture disinfection with a disinfectant spray for dental practice and the use of patients. 2. Virological studies; the evaluation summary]. / Mikrobiologisch-experimentelle Untersuchungen zur Instrumenten- und Prothesendesinfektion mit Desinfektionsmittel-Sprays für die stomatologische Praxis und zu Händen des Patienten. 2. Mitteilung: Virologische Untersuchungen; zusammenfassende Bewertung.

Carrier experiments using Echo- and Influenza-viruses on denture basis resins and fragments of orthodontic appliances resulted in good and even very good virucidal effects of disinfectant sprays Desident and Fesia-sept. The application of the disinfectant as spray seem to be advantageous, but is not recommendable. The diverse causes of this conclusion are discussed and an alternative way is proposed.

In vitro and in vivo anti-picornavirus activity of some p-benzoylphenoxypyridines.

Fifteen p-benzoylphenoxypyridines were initially evaluated for their in vitro activity against rhinoviruses (RV) 1A, 2 and 64 and coxsackie virus (Cox) A21 and for their oral prophylactic and therapeutic activity in Swiss albino mice lethally challenged with Cox A21. One compound, (4-[(5-methylsulfonyl-2-pyridinyl)oxy]phenyl) phenyl methanone, was selected for additional evaluation. These studies showed the compound to possess MIC50 values of less than or equal to 5 micrograms/ml against only 6 of 20 (30.0%) RV serotypes tested. In contrast, the compound was active at concentrations of less than or equal to 5.0 micrograms/ml against 10 of 12 (83.3%) enteroviruses evaluated. In vivo studies showed the compound to significantly protect mice lethally infected with Cox A21 after a single oral dose of 37.5 mg/kg (P less than 0.02) and during a regimen of continuous oral doses of at least 4.7 mg/kg per day (P less than 0.001). Mechanism of action studies indicated that the compound inhibits picornavirus uncoating or some earlier virus-host cell-associated event. Isotopic studies show that (4-[(5-methylsulfonyl-2-pyridinyl)oxy]phenyl) phenyl methanone perturbs HeLa cell macromolecular synthesis at concentrations of as low as 3.12 micrograms/ml. This concentration is only 4-fold higher than the concentration of compound necessary to inhibit Cox A21 RNA synthesis by 90%. This narrow therapeutic ratio limits the potential clinical utility of this compound to all but the most serious picornavirus infections.