{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T12:41:17Z","timestamp":1774269677874,"version":"3.50.1"},"reference-count":42,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2022,3,15]],"date-time":"2022-03-15T00:00:00Z","timestamp":1647302400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001824","name":"Czech Science Foundation","doi-asserted-by":"publisher","award":["21-25280S"],"award-info":[{"award-number":["21-25280S"]}],"id":[{"id":"10.13039\/501100001824","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Positive-sense single-stranded RNA (+RNA) viruses have proven to be important pathogens that are able to threaten and deeply damage modern societies, as illustrated by the ongoing COVID-19 pandemic. Therefore, compounds active against most or many +RNA viruses are urgently needed. Here, we present PR673, a helquat-like compound that is able to inhibit the replication of SARS-CoV-2 and tick-borne encephalitis virus in cell culture. Using in vitro polymerase assays, we demonstrate that PR673 inhibits RNA synthesis by viral RNA-dependent RNA polymerases (RdRps). Our results illustrate that the development of broad-spectrum non-nucleoside inhibitors of RdRps is feasible.<\/jats:p>","DOI":"10.3390\/molecules27061894","type":"journal-article","created":{"date-parts":[[2022,3,16]],"date-time":"2022-03-16T03:36:23Z","timestamp":1647401783000},"page":"1894","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["A Helquat-like Compound as a Potent Inhibitor of Flaviviral and Coronaviral Polymerases"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0285-3843","authenticated-orcid":false,"given":"Eva","family":"Konkolova","sequence":"first","affiliation":[{"name":"Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo n\u00e1m. 2, 16610 Prague, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kate\u0159ina","family":"Krej\u010dov\u00e1","sequence":"additional","affiliation":[{"name":"Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo n\u00e1m. 2, 16610 Prague, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lud\u011bk","family":"Eyer","sequence":"additional","affiliation":[{"name":"Laboratory of Emerging Viral Diseases, Veterinary Research Institute, Hudcova 296\/70, 62100 Brno, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jan","family":"Hodek","sequence":"additional","affiliation":[{"name":"Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo n\u00e1m. 2, 16610 Prague, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4747-9242","authenticated-orcid":false,"given":"Michala","family":"Zgarbov\u00e1","sequence":"additional","affiliation":[{"name":"Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo n\u00e1m. 2, 16610 Prague, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andrea","family":"Fo\u0159tov\u00e1","sequence":"additional","affiliation":[{"name":"Laboratory of Emerging Viral Diseases, Veterinary Research Institute, Hudcova 296\/70, 62100 Brno, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael","family":"Jirasek","sequence":"additional","affiliation":[{"name":"Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo n\u00e1m. 2, 16610 Prague, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Filip","family":"Teply","sequence":"additional","affiliation":[{"name":"Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo n\u00e1m. 2, 16610 Prague, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paul","family":"Reyes-Gutierrez","sequence":"additional","affiliation":[{"name":"Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo n\u00e1m. 2, 16610 Prague, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4655-2380","authenticated-orcid":false,"given":"Daniel","family":"R\u016f\u017eek","sequence":"additional","affiliation":[{"name":"Laboratory of Emerging Viral Diseases, Veterinary Research Institute, Hudcova 296\/70, 62100 Brno, Czech Republic"},{"name":"Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Brani\u0161ovsk\u00e1 1160\/31, 37005 Ceske Budejovice, Czech Republic"},{"name":"Department of Experimental Biology, Faculty of Science, Masaryk University, 62500 Brno, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2799-7352","authenticated-orcid":false,"given":"Jan","family":"Weber","sequence":"additional","affiliation":[{"name":"Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo n\u00e1m. 2, 16610 Prague, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9652-4065","authenticated-orcid":false,"given":"Evzen","family":"Boura","sequence":"additional","affiliation":[{"name":"Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo n\u00e1m. 2, 16610 Prague, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Moureau, G., Cook, S., Lemey, P., Nougairede, A., Forrester, N.L., Khasnatinov, M., Charrel, R.N., Firth, A.E., Gould, E.A., and de Lamballerie, X. 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