Discovery of Nanomolar DCAF1 Small Molecule Ligands
作者:Alice Shi Ming Li、Serah Kimani、Brian Wilson、Mahmoud Noureldin、Héctor González-Álvarez、Ahmed Mamai、Laurent Hoffer、John P. Guilinger、Ying Zhang、Moritz von Rechenberg、Jeremy S. Disch、Christopher J. Mulhern、Belinda L. Slakman、John W. Cuozzo、Aiping Dong、Gennady Poda、Mohammed Mohammed、Punit Saraon、Manish Mittal、Pratik Modh、Vaibhavi Rathod、Bhashant Patel、Suzanne Ackloo、Vijayaratnam Santhakumar、Magdalena M Szewczyk、Dalia Barsyte-Lovejoy、Cheryl H. Arrowsmith、Richard Marcellus、Marie-Aude Guié、Anthony D. Keefe、Peter J. Brown、Levon Halabelian、Rima Al-awar、Masoud Vedadi
DOI:10.1021/acs.jmedchem.2c02132
日期:——
learning. This led to the discovery of a compound (Z1391232269) with an SPR KD of 11 μM. Structure-guided hit optimization led to the discovery of OICR-8268 (26e) with an SPR KD of 38 nM and cellular target engagement with EC50 of 10 μM as measured by cellular thermal shift assay (CETSA). OICR-8268 is an excellent tool compound to enable the development of next-generation DCAF1ligands toward cancer therapeutics
Identification of non-peptidic cysteine reactive fragments as inhibitors of cysteine protease rhodesain
作者:Danielle McShan、Stefan Kathman、Brittiney Lowe、Ziyang Xu、Jennifer Zhan、Alexander Statsyuk、Ifedayo Victor Ogungbe
DOI:10.1016/j.bmcl.2015.08.074
日期:2015.10
Rhodesain, the major cathepsin L-like cysteine protease in the protozoan Trypanosoma brucei rhodesiense, the causative agent of African sleeping sickness, is a well-validated drug target. In this work, we used a fragment-based approach to identify inhibitors of this cysteine protease, and identified inhibitors of T. brucei. To discover inhibitors active against rhodesain and T. brucei, we screened a library of covalent fragments against rhodesain and conducted preliminary SAR studies. We envision that in vitro enzymatic assays will further expand the use of the covalent tethering method, a simple fragment-based drug discovery technique to discover covalent drug leads. (C) 2015 Elsevier Ltd. All rights reserved.
A Small Molecule That Switches a Ubiquitin Ligase From a Processive to a Distributive Enzymatic Mechanism
作者:Stefan G. Kathman、Ingrid Span、Aaron T. Smith、Ziyang Xu、Jennifer Zhan、Amy C. Rosenzweig、Alexander V. Statsyuk
DOI:10.1021/jacs.5b06839
日期:2015.10.7
E3 ligases are genetically implicated in many human diseases, yet E3 enzyme mechanisms are not fully understood, and there is a strong need for pharmacological probes of E3s. We report the discovery that the HECT E3 Nedd4-1 is a processive enzyme and that disruption of its processivity by biochemical mutations or small molecules switches Nedd4-1 from a processive to a distributive mechanism of polyubiquitin chain synthesis. Furthermore, we discovered and structurally characterized the first covalent inhibitor of Nedd4-1, which switches Nedd4-1 from a processive to a distributive mechanism. To visualize the binding mode of the Nedd4-1 inhibitor, we used X-ray crystallography and solved the first structure of a Nedd4-1 family ligase bound to an inhibitor. Importantly, our study shows that processive Nedd4-1, but not the distributive Nedd4-1:inhibitor complex, is able to synthesize polyubiquitin chains on the substrate in the presence of the deubiquitinating enzyme USP8. Therefore, inhibition of E3 ligase processivity is a viable strategy to design E3 inhibitors. Our study provides fundamental insights into the HECT E3 mechanism and uncovers a novel class of HECT E3 inhibitors.
A Fragment-Based Method to Discover Irreversible Covalent Inhibitors of Cysteine Proteases
作者:Stefan G. Kathman、Ziyang Xu、Alexander V. Statsyuk
DOI:10.1021/jm500345q
日期:2014.6.12
reported which irreversibly tethers drug-like fragments to catalytic cysteines. We attached an electrophile to 100 fragments without significant alterations in the reactivity of the electrophile. A mass spectrometry assay discovered three nonpeptidic inhibitors of the cysteineprotease papain. The identified compounds display the characteristics of irreversibleinhibitors. The irreversible tethering system
Synthesis of 3-Substituted Arylpyrazole-4-carboxylic Acids
作者:A. V. Lebedev、A. B. Lebedeva、V. D. Sheludyakov、E. A. Kovaleva、O. L. Ustinova、I. B. Kozhevnikov
DOI:10.1007/s11176-005-0318-7
日期:2005.5
3-aryl-substituted pyrazole-4-carboxylic acids, involving Vilsmeier formylation of semicarbazones of 26 available mono- and disubstituted acetophenones and 2-acetylthiophene followed by oxidation of the resulting 3-aryl-substituted pyrazole-4-carboxaldehydes under the action of potassium permanganate. The mechanism of the formylation reaction is discussed. The method successfully works even with acetophenones