Design and synthesis of novel inhibitors of viral methyltransferases

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388963%3A_____%2F25%3A00643105" target="_blank" >RIV/61388963:_____/25:00643105 - isvavai.cz</a>

Výsledek na webu

<a href="http://www.ccsss.cz/index.php/ccsss/issue/view/52/92" target="_blank" >http://www.ccsss.cz/index.php/ccsss/issue/view/52/92</a>

DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Design and synthesis of novel inhibitors of viral methyltransferases

Popis výsledku v původním jazyce

Viral methyltransferases (MTases) are essential enzymes that secure efficient RNA translation and protect viral transcripts from host innate immunity by participating in the capping of their 5′ ends. These enzymes have emerged as highly attractive antiviral targets, and their inhibition offers apromising strategy to block viral replication1. Our research group has developed extensive expertise in the design and synthesis of nucleoside-based MTase inhibitors, particularly through modifications of the 7-deazapurine scaffold. Since the 2020 outbreak of SARS-CoV-2, we have made significant contributions to the discovery of coronavirus MTase inhibitors, focusing on the N7-MTase non-structural protein 14 (nsp14). Using a structure-based approach, we designed 7-deazapurine analogues of S-adenosylhomocysteine (SAH) that engage a lateral cavity adjacent to the S-adenosylmethionine (SAM) binding site2. Follow-up work led to the design and synthesis of bisubstrate inhibitors of nsp14 by incorporating modifications into both the adenine base and the amino acid side chain (Fig.1, structure A)3. These analogues exploit interactions in the SAM-binding site as well as part of the adjacent RNA-binding region. Several lead compounds demonstrated nanomolar inhibitory activity in biochemical assays against SARS-CoV-2 nsp14 and exhibited excellent selectivity over human MTases. Structural studies confirmed the bisubstrate character of these inhibitors and revealed that bulky C7 substituents displace an ordered water network normally mediating SAM binding4. In parallel, work by our colleagues has established the mpox virus 2′-O-MTase VP39 as a promising antiviral target. Structural analyses demonstrated that C7-substituted SAH analogues bind to VP39 in a conserved fashion, while cellular assays showed that such inhibitors suppress mpox virus replication5,6. Building on this foundation, we developed a new series of VP39 inhibitors (Fig.1, structure B). Using the SAH template with canonical amino acid residues at the 5′-position, we explored C7 substitution with diverse branched substituents. Among the synthesized series, carboxamide-linked analogues showed promising inhibitory activity in enzymatic assays, providing a basis for further optimization. In addition, while investigating suitable C7 substituents, we expanded the chemistry of this position to synthesize C7- sulfonamido-7-deazaadenosines, a structural type not previously reported. This strategy enabled efficient diversification and afforded sangivamycin derivatives with potent activity against Haspin kinase. Together, these results illustrate how targeted modifications at the 5′- and C7-positions of 7-deazapurines can yield inhibitors of viral MTases while also introducing anovel class of nucleosides with kinase activity. These outcomes broaden the scope of nucleoside-based medicinal chemistry and contribute to the wider collaborative effort on viral enzymes and related therapeutic targets.nThe work was supported by the project National Institute of Virology and Bacteriology (Programme EXCELES, ID Project No. LX22NPO5103) – Funded by the European Union – NextGenerationEU.

Název v anglickém jazyce

Design and synthesis of novel inhibitors of viral methyltransferases

Popis výsledku anglicky

Viral methyltransferases (MTases) are essential enzymes that secure efficient RNA translation and protect viral transcripts from host innate immunity by participating in the capping of their 5′ ends. These enzymes have emerged as highly attractive antiviral targets, and their inhibition offers apromising strategy to block viral replication1. Our research group has developed extensive expertise in the design and synthesis of nucleoside-based MTase inhibitors, particularly through modifications of the 7-deazapurine scaffold. Since the 2020 outbreak of SARS-CoV-2, we have made significant contributions to the discovery of coronavirus MTase inhibitors, focusing on the N7-MTase non-structural protein 14 (nsp14). Using a structure-based approach, we designed 7-deazapurine analogues of S-adenosylhomocysteine (SAH) that engage a lateral cavity adjacent to the S-adenosylmethionine (SAM) binding site2. Follow-up work led to the design and synthesis of bisubstrate inhibitors of nsp14 by incorporating modifications into both the adenine base and the amino acid side chain (Fig.1, structure A)3. These analogues exploit interactions in the SAM-binding site as well as part of the adjacent RNA-binding region. Several lead compounds demonstrated nanomolar inhibitory activity in biochemical assays against SARS-CoV-2 nsp14 and exhibited excellent selectivity over human MTases. Structural studies confirmed the bisubstrate character of these inhibitors and revealed that bulky C7 substituents displace an ordered water network normally mediating SAM binding4. In parallel, work by our colleagues has established the mpox virus 2′-O-MTase VP39 as a promising antiviral target. Structural analyses demonstrated that C7-substituted SAH analogues bind to VP39 in a conserved fashion, while cellular assays showed that such inhibitors suppress mpox virus replication5,6. Building on this foundation, we developed a new series of VP39 inhibitors (Fig.1, structure B). Using the SAH template with canonical amino acid residues at the 5′-position, we explored C7 substitution with diverse branched substituents. Among the synthesized series, carboxamide-linked analogues showed promising inhibitory activity in enzymatic assays, providing a basis for further optimization. In addition, while investigating suitable C7 substituents, we expanded the chemistry of this position to synthesize C7- sulfonamido-7-deazaadenosines, a structural type not previously reported. This strategy enabled efficient diversification and afforded sangivamycin derivatives with potent activity against Haspin kinase. Together, these results illustrate how targeted modifications at the 5′- and C7-positions of 7-deazapurines can yield inhibitors of viral MTases while also introducing anovel class of nucleosides with kinase activity. These outcomes broaden the scope of nucleoside-based medicinal chemistry and contribute to the wider collaborative effort on viral enzymes and related therapeutic targets.nThe work was supported by the project National Institute of Virology and Bacteriology (Programme EXCELES, ID Project No. LX22NPO5103) – Funded by the European Union – NextGenerationEU.

Druh

O - Ostatní výsledky

CEP obor

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OECD FORD obor

10608 - Biochemistry and molecular biology

Projekt

<a href="/cs/project/LX22NPO5103" target="_blank" >LX22NPO5103: Národní institut virologie a bakteriologie</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů