Syntheses of 1, 2, and 9-methyl derivatives of 4,9-dihydro-3-methyl-4-oxo-1H(2H)-pyrazolo[3,4-b]quinoline and their antiviral activity

1985 ◽  
Vol 50 (5) ◽  
pp. 1057-1063 ◽  
Author(s):  
Stanislav Rádl ◽  
Viktor Zikán ◽  
František Šmejkal
Keyword(s):  
Influenza Virus ◽  
Antiviral Activity ◽  
Methyl Iodide ◽  
Room Temperature ◽  
Encephalomyocarditis Virus ◽  
Methyl Derivative ◽  
Sodium Salts ◽  
Methyl Derivatives ◽  
Derivatives Of

The paper describes syntheses of 4,9-dihydro-3-methyl-4-oxo-1H(2H)-pyrazolo[3,4-b]quinoline (Ia), its 1-methyl derivative (Ib), 2-methyl derivative (IIa), 9-methyl derivative (Ic), 1,9-dimethyl derivative (Id) and 2,9-dimethyl derivative (IIb). Sodium salts of compounds Ia, Ib, Ic and IIa were methylated with methyl iodide in dimethylformamide at room temperature, compounds Id and IIb were demethylated with pyridine hydrochloride. The compounds prepared were tested for antiviral activity in vivo in mice against influenza virus A2-Hongkong and the Encephalomyocarditis virus.

Synthesis of 1,2, and 9-methyl derivatives of 4,9-dihydro-6-methoxy-3-methyl-4-oxo-1H(2H)-pyrazolo[3,4-b]quinoline and 4,9-dihydro-6-hydroxy-3-methyl-4-oxo-1H(2H)-pyrazolo[3,4-b]quinoline and their antiviral activity

1987 ◽  
Vol 52 (3) ◽  
pp. 788-792 ◽  
Author(s):  
Stanislav Rádl ◽  
Viktor Zikán
Keyword(s):  
Influenza Virus ◽  
Antiviral Activity ◽  
Hydrobromic Acid ◽  
Encephalomyocarditis Virus ◽  
Methyl Derivative ◽  
Pyridine Hydrochloride ◽  
Methyl Derivatives ◽  
Derivatives Of

The paper describes syntheses of 4,9-dihydro-6-methoxy-3-methyl-4-oxo-1H(2H)-pyrazolo[3,4-b]quinoline (Ia), its 1-methyl derivative (Ic), 1,9-dimethyl derivative (Ie), 2-methyl derivative (IIa), and 2,9-dimethyl derivative (IIc). Demethylation of these compounds with hydrobromic acid afforded 4,9-dihydro-6-hydroxy-3-methyl-4-oxo-1H(2H)-pyrazolo[3,4-b]quinoline (Ib), its 1-methyl derivative (Id), 1,9-dimethyl derivative (If), 2-methyl derivative (IIb), and 2,9-dimethyl derivative (IId) respectively. 4,9-Dihydro-6-hydroxy-3,9-dimethyl-4-oxo-1H-pyrazolo[3,4-b]quinoline (Ig) was prepared by demethylation of Ie and/or IIc with pyridine hydrochloride. The compounds prepared were tested for antiviral activity in vivo in mice against influenza virus A2-Hongkong and encephalomyocarditis virus.

Syntheses of some 4-dialkylaminoalkylamino derivatives of 2,3-dimethyl-2H- and 3,9-dimethyl-9H-pyrazolo[3,4-b]quinoline

1986 ◽  
Vol 51 (8) ◽  
pp. 1692-1697 ◽  
Author(s):  
Stanislav Rádl ◽  
Viktor Zikán
Keyword(s):  
Influenza Virus ◽  
Thionyl Chloride ◽  
Encephalomyocarditis Virus ◽  
Methoxy Derivative ◽  
Derivatives Of

Reactions of 4-chloro-2,3-dimethyl-2H-pyrazolo[3,4-b]quinoline and 4-chloro-6-methoxy-2,3-dimethyl-2H-pyrazolo[3,4-b]quinoline with 3-dimethylaminopropylamine and/or 2-dimethylaminoethylamine afforded 4-(3-dimethylaminopropylamino)-2,3-dimethyl-2H-pyrazolo[3,4-b]quinoline (IIa), its 6-methoxy derivative (IIc), 4-(2-diethylaminoethylamino)-2,3-dimethyl-2H-pyrazolo[3,4-b]quinoline (IIb) and its 6-methoxy derivative (IId). Reaction of 4,9-dihydro-3,9-dimethyl-4-oxo-1H-pyrazolo[3,4-b]quinoline with thionyl chloride gave an intermediate, whose reaction with 3-dimethylaminopropylamine afforded 4-(3-dimethylaminopropylamino)-3,9-dimethyl-9H-pyrazolo[3,4-b]quinoline (III). The compounds were tested in vivo in mice for efficacy against the A2-Hongkong influenza virus and the encephalomyocarditis virus.

Synthesis and biological activity of some basic-substituted 4,9-dihydro-3-methyl-4-oxo-1H(2H)-pyrazolo[3,4-b]quinolines

1988 ◽  
Vol 53 (8) ◽  
pp. 1812-1819
Author(s):  
Stanislav Rádl ◽  
Viktor Zikán
Keyword(s):  
Influenza Virus ◽  
Biological Activity ◽  
Antiviral Activity ◽  
Encephalomyocarditis Virus ◽  
Methoxy Derivative

Compounds Ia, Ib were obtained by an alkylation of 4,9-dihydro-6-hydroxy-1,3,9-trimethyl-4-oxo-1H-pyrazolo[3,4-b]quinoline (VIIb) with the respective dialkylaminoalkyl chloride. The same alkylation of 4,9-dihydro-6-hydroxy-2,3,9-trimethyl-4-oxo-2H-pyrazolo[3,4-b]quinoline (VIIIb) yielded compounds IIa and IIb. Similar alkylation of 4,9-dihydro-6-hydroxy-3,9-dimethyl-4-oxo-1H-pyrazolo[3,4-b]quinoline (IXa) and its 6-methoxy derivative (IXb) afforded IIIa-IIId. Compound IV was prepared from 4-chloro-3-methyl-1H-pyrazolo[3,4-b]quinoline (Xa) via its 1-(3-dimethylaminopropyl)derivative (Xb). Compounds VIa, VIb were prepared from 4,9-dihydro-6-hydroxy-3,9-dimethyl-4-oxo-1H-pyrazolo[3,4-b]quinoline (IXc) and the respective dialkylaminoalkyl chloride. The compounds prepared were tested for antiviral activity in vivo in mice against influenza virus A2-Hongkong and encephalomyocarditis virus.

scholarly journals Antiviral Activity of Fritillaria thunbergii Extract against Human Influenza Virus H1N1 (PR8) In Vitro, In Ovo and In Vivo

2020 ◽  
Vol 30 (2) ◽  
pp. 172-177 ◽  
Author(s):  
Minjee Kim ◽  
Dinh-Van Nguyen ◽  
Yoonki Heo ◽  
Ki Hoon Park ◽  
Hyun-Dong Paik ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Antiviral Activity ◽  
Virus H1n1 ◽  
Human Influenza ◽  
In Ovo ◽  
Human Influenza Virus

scholarly journals Antiviral activity of plant juices and green tea against SARS-CoV-2 and influenza virus in vitro

2020 ◽  
Author(s):  
Bruno Frank ◽  
Carina Conzelmann ◽  
Tatjana Weil ◽  
Rüdiger Groß ◽  
Peggy Jungke ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Antiviral Activity ◽  
Green Tea ◽  
Human Adenovirus ◽  
Virus Infectivity ◽  
Virucidal Activity ◽  
Black Chokeberry ◽  
Chokeberry Juice

AbstractMany plant juices, extracts and teas have been shown to possess antiviral activity. We here analyzed the virucidal activity of black chokeberry (Aronia melanocarpa), pomegranate (Punica granatum), and elderberry (Sambucus nigra) juice, as well as green tea (Camellia sinensis) against different respiratory viruses. We found that all tested plant derived products effectively inactivated influenza virus, whereas only chokeberry juice diminished SARS-CoV-2 and vaccinia virus infectivity. None of the products inactivated non-enveloped human adenovirus type 5. Thus, black chokeberry juice exerts virucidal activity against different enveloped viral pathogens under in vitro conditions. Whether application of virucidal juices or green tea as oral rinses may lower viral loads in the oral cavity in vivo remains to be evaluated.

POTASSIUM DERIVATIVES OF FLUORENE AS INTERMEDIATES IN THE PREPARATION OF C9-SUBSTITUTED FLUORENES: III. THE INFLUENCE OF SOLVENT AND METAL IN THE FORMATION OF C9-SUBSTITUTED FLUORENES FROM 9-FLUORENYL METALS

1961 ◽  
Vol 39 (4) ◽  
pp. 799-807 ◽  
Author(s):  
G. W. H. Scherf ◽  
R. K. Brown
Keyword(s):  
Methyl Iodide ◽  
Benzyl Chloride ◽  
Room Temperature ◽  
Organometallic Compounds ◽  
Lithium Compound ◽  
Hydrocarbon Solvents ◽  
Derivatives Of ◽  
Ether Solvents ◽  
Potassium Compound ◽  
Influence Of Solvent

Equimolar quantities of 9-fluorenyl-potassium, -sodium, or -lithium and alkyl or aralkyl halides at room temperature in ether solvents yielded a mixture of unchanged fluorene, C9-monosubstituted fluorene, and C9-disubstituted fluorene. The amount of disubstitution never exceeded that of unchanged fluorene, and was found to be maximum (∼35%) for the potassium compound in 1,2-dimethoxyethane, somewhat less for the sodium analogue, and small (∼5%) for the lithium compound. In hydrocarbon solvents such as hexane, 9-fluorenylpotassium gave only 7% of C9-disubstituted fluorene. The lithium compound, upon reaction with methyl iodide or ethyl iodide gave, along with unreacted fluorene, only C9-monosubstituted fluorene. But reaction of 9-fluorenyllithium with benzyl chloride in hexane gave a small quantity (∼5%) of disubstituted fluorene as well as the monosubstituted product.The results are explained in terms of (a) the solubilities of the organometallic compounds in ether and hydrocarbon solvents, (b) the polarity of the metal carbon bond, and (c) the acidity of the hydrogen on C9 of fluorene.

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