Synthesis and evaluation of the antiviral activity of 2-(dichloromethyl)pyrazolo[1,5-a][1,3,5]triazines

It is found that N-(2,2-dichloro-1-cyanoethenyl)carboxamides react with 1H-pyrazol-5-amines in the presence of triethylamine to give 2-(dichloromethyl)pyrazolo[1,5-a][1,3,5]triazines. Apparently, this cyclocondensation con sists of the following steps: a) the addition of an NH2 group to the activate...

Full description

Bibliographic Details
Main Authors: Ye.S. Velihina, S.G. Pil’o, V.S. Zyabrev, V.S. Brovarets
Format: Article
Language:English
Published: Publishing House "Akademperiodyka" 2019-07-01
Series:Доповiдi Нацiональної академiї наук України
Subjects:
Online Access:http://dopovidi-nanu.org.ua/en/archive/2019/7/10
_version_ 1811317941251080192
author Ye.S. Velihina
S.G. Pil’o
V.S. Zyabrev
V.S. Brovarets
author_facet Ye.S. Velihina
S.G. Pil’o
V.S. Zyabrev
V.S. Brovarets
author_sort Ye.S. Velihina
collection DOAJ
description It is found that N-(2,2-dichloro-1-cyanoethenyl)carboxamides react with 1H-pyrazol-5-amines in the presence of triethylamine to give 2-(dichloromethyl)pyrazolo[1,5-a][1,3,5]triazines. Apparently, this cyclocondensation con sists of the following steps: a) the addition of an NH2 group to the activated C=C bond to form the first amide intermediate, b) the elimination of HCN promoted by triethylamine to give the second amide intermediate, c) the intramolecular cyclization of the latter into the final product with H2O elimination. 2 (Dichloromethyl)-4,7-diphenylpyrazolo[1,5-a] [1,3,5]triazine was stable to boiling MeONa/MeOH, AcONa/AcOH, and Na2S/H2O/EtOH solutions, but cleaved with hydrochloric or sulfuric acid. Five 2-(dichloromethyl)pyrazolo[1,5-a][1,3,5]triazines are tested against i) Dengue virus 2 (strain New Guinea C, cell line Huh7), ii) Tacaribe virus (strain TRVL 11573, cell line Vero), iii) Zika virus (strain MR766, cell line Vero 76), iv) Human cytomegalovirus (strain AD169, cell line HFF), v) Herpes simplex virus 1 (strain E-377, cell line HFF), vi) Varicella-Zoster virus (strain Ellen, cell line HFF). The viral-induced cytopathic effect inhibition, as well as the compound toxicity in host cells, is evaluated. In primary assays (i-iii), the compounds have no sufficient antiviral activity that would exceed their cytotoxicity level at concentrations within 0.1-100 μg/mL, but assays (iv-vi) gave acceptable results. All compounds showed rather a low activity with the exception of 2-(dichloromethyl)-4,7- diphenylpyrazolo[1,5-a][1,3,5]triazine, which, however, had a comparatively high toxicity. In terms of selectivity, the interaction 2-(dichloromethyl)-4,7-bis(4-methylphenyl)pyrazolo[1,5-a][1,3,5]triazine—AD169—HFF (assay iv) with SI50 > 6 is noteworthy.
first_indexed 2024-04-13T12:17:08Z
format Article
id doaj.art-61e9e2c4ed014e3b8ad4f785da2944c2
institution Directory Open Access Journal
issn 1025-6415
2518-153X
language English
last_indexed 2024-04-13T12:17:08Z
publishDate 2019-07-01
publisher Publishing House "Akademperiodyka"
record_format Article
series Доповiдi Нацiональної академiї наук України
spelling doaj.art-61e9e2c4ed014e3b8ad4f785da2944c22022-12-22T02:47:20ZengPublishing House "Akademperiodyka"Доповiдi Нацiональної академiї наук України1025-64152518-153X2019-07-017758010.15407/dopovidi2019.07.075Synthesis and evaluation of the antiviral activity of 2-(dichloromethyl)pyrazolo[1,5-a][1,3,5]triazinesYe.S. Velihina0S.G. Pil’o1V.S. Zyabrev2V.S. Brovarets3V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the NAS of Ukraine, KyivV.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the NAS of Ukraine, KyivV.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the NAS of Ukraine, KyivV.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the NAS of Ukraine, KyivIt is found that N-(2,2-dichloro-1-cyanoethenyl)carboxamides react with 1H-pyrazol-5-amines in the presence of triethylamine to give 2-(dichloromethyl)pyrazolo[1,5-a][1,3,5]triazines. Apparently, this cyclocondensation con sists of the following steps: a) the addition of an NH2 group to the activated C=C bond to form the first amide intermediate, b) the elimination of HCN promoted by triethylamine to give the second amide intermediate, c) the intramolecular cyclization of the latter into the final product with H2O elimination. 2 (Dichloromethyl)-4,7-diphenylpyrazolo[1,5-a] [1,3,5]triazine was stable to boiling MeONa/MeOH, AcONa/AcOH, and Na2S/H2O/EtOH solutions, but cleaved with hydrochloric or sulfuric acid. Five 2-(dichloromethyl)pyrazolo[1,5-a][1,3,5]triazines are tested against i) Dengue virus 2 (strain New Guinea C, cell line Huh7), ii) Tacaribe virus (strain TRVL 11573, cell line Vero), iii) Zika virus (strain MR766, cell line Vero 76), iv) Human cytomegalovirus (strain AD169, cell line HFF), v) Herpes simplex virus 1 (strain E-377, cell line HFF), vi) Varicella-Zoster virus (strain Ellen, cell line HFF). The viral-induced cytopathic effect inhibition, as well as the compound toxicity in host cells, is evaluated. In primary assays (i-iii), the compounds have no sufficient antiviral activity that would exceed their cytotoxicity level at concentrations within 0.1-100 μg/mL, but assays (iv-vi) gave acceptable results. All compounds showed rather a low activity with the exception of 2-(dichloromethyl)-4,7- diphenylpyrazolo[1,5-a][1,3,5]triazine, which, however, had a comparatively high toxicity. In terms of selectivity, the interaction 2-(dichloromethyl)-4,7-bis(4-methylphenyl)pyrazolo[1,5-a][1,3,5]triazine—AD169—HFF (assay iv) with SI50 > 6 is noteworthy.http://dopovidi-nanu.org.ua/en/archive/2019/7/10N-(22-dichloro-1-cyanoethenyl)carboxamide1H-pyrazol-5-aminepyrazolo[15-a][135]triazine
spellingShingle Ye.S. Velihina
S.G. Pil’o
V.S. Zyabrev
V.S. Brovarets
Synthesis and evaluation of the antiviral activity of 2-(dichloromethyl)pyrazolo[1,5-a][1,3,5]triazines
Доповiдi Нацiональної академiї наук України
N-(2
2-dichloro-1-cyanoethenyl)carboxamide
1H-pyrazol-5-amine
pyrazolo[1
5-a][1
3
5]triazine
title Synthesis and evaluation of the antiviral activity of 2-(dichloromethyl)pyrazolo[1,5-a][1,3,5]triazines
title_full Synthesis and evaluation of the antiviral activity of 2-(dichloromethyl)pyrazolo[1,5-a][1,3,5]triazines
title_fullStr Synthesis and evaluation of the antiviral activity of 2-(dichloromethyl)pyrazolo[1,5-a][1,3,5]triazines
title_full_unstemmed Synthesis and evaluation of the antiviral activity of 2-(dichloromethyl)pyrazolo[1,5-a][1,3,5]triazines
title_short Synthesis and evaluation of the antiviral activity of 2-(dichloromethyl)pyrazolo[1,5-a][1,3,5]triazines
title_sort synthesis and evaluation of the antiviral activity of 2 dichloromethyl pyrazolo 1 5 a 1 3 5 triazines
topic N-(2
2-dichloro-1-cyanoethenyl)carboxamide
1H-pyrazol-5-amine
pyrazolo[1
5-a][1
3
5]triazine
url http://dopovidi-nanu.org.ua/en/archive/2019/7/10
work_keys_str_mv AT yesvelihina synthesisandevaluationoftheantiviralactivityof2dichloromethylpyrazolo15a135triazines
AT sgpilo synthesisandevaluationoftheantiviralactivityof2dichloromethylpyrazolo15a135triazines
AT vszyabrev synthesisandevaluationoftheantiviralactivityof2dichloromethylpyrazolo15a135triazines
AT vsbrovarets synthesisandevaluationoftheantiviralactivityof2dichloromethylpyrazolo15a135triazines