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Immunoproteasome inhibition and bioactivity of thiasyrbactins.

ABSTRACT: A family of macrodilactam natural products, the syrbactins, are known proteasome inhibitors. A small group of syrbactin analogs was prepared with a sulfur-for-carbon substitution to enhance synthetic accessibility and facilitate modulation of their solubility. Two of these compounds surprisingly proved to be inhibitors of the trypsin-like catalytic site, including of the immunoproteasome. Their bound and free conformations suggest special properties of the thiasyrbactin ring are responsible for this unusual preference, which may be exploited to develop drug-like immunoproteasome inhibitors. These compounds show greater selectivity than earlier compounds used to infer phenotypes of immunoproteasome inhibition, like ONX-0914.

SUBMITTER: Bakas NA

PROVIDER: S-EPMC5920785 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Immunoproteasome inhibition and bioactivity of thiasyrbactins.

Bakas Nicole A NA Schultz Chad R CR Yco Lisette P LP Roberts Christopher C CC Chang Chia-En A CA Bachmann André S AS Pirrung Michael C MC

Bioorganic & medicinal chemistry 20171207 2

A family of macrodilactam natural products, the syrbactins, are known proteasome inhibitors. A small group of syrbactin analogs was prepared with a sulfur-for-carbon substitution to enhance synthetic accessibility and facilitate modulation of their solubility. Two of these compounds surprisingly proved to be inhibitors of the trypsin-like catalytic site, including of the immunoproteasome. Their bound and free conformations suggest special properties of the thiasyrbactin ring are responsible for ...[more]

PMID: 29269255

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