ABSTRACT
Ubiquitination controls the stability of most cellular proteins, and its deregulation contributes to human diseases including cancer. Deubiquitinases remove ubiquitin from proteins, and their inhibition can induce the degradation of selected proteins, potentially including otherwise 'undruggable' targets. For example, the inhibition of ubiquitin-specific protease 7 (USP7) results in the degradation of the oncogenic E3 ligase MDM2, and leads to re-activation of the tumour suppressor p53 in various cancers. Here we report that two compounds, FT671 and FT827, inhibit USP7 with high affinity and specificity in vitro and within human cells. Co-crystal structures reveal that both compounds target a dynamic pocket near the catalytic centre of the auto-inhibited apo form of USP7, which differs from other USP deubiquitinases. Consistent with USP7 target engagement in cells, FT671 destabilizes USP7 substrates including MDM2, increases levels of p53, and results in the transcription of p53 target genes, induction of the tumour suppressor p21, and inhibition of tumour growth in mice.
Subject(s)
Piperidines/pharmacology , Pyrazoles/pharmacology , Pyrimidines/pharmacology , Ubiquitin-Specific Peptidase 7/antagonists & inhibitors , Animals , Apoenzymes/antagonists & inhibitors , Apoenzymes/chemistry , Apoenzymes/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Crystallography, X-Ray , Female , Humans , Mice , Models, Molecular , Neoplasms/drug therapy , Neoplasms/enzymology , Neoplasms/pathology , Piperidines/chemical synthesis , Proto-Oncogene Proteins c-mdm2/chemistry , Proto-Oncogene Proteins c-mdm2/metabolism , Pyrazoles/chemical synthesis , Pyrimidines/chemical synthesis , Substrate Specificity , Transcription, Genetic/drug effects , Tumor Suppressor Protein p53/metabolism , Ubiquitin-Specific Peptidase 7/chemistry , Ubiquitin-Specific Peptidase 7/metabolism , Ubiquitination/drug effects , Xenograft Model Antitumor AssaysABSTRACT
The Garner aldehyde-derived methylene alkene 5 and the corresponding benzyloxycarbonyl compound 25 undergo hydroboration with 9-BBN-H followed by palladium-catalyzed Suzuki coupling reactions with aryl and vinyl halides. After one-pot hydrolysis-oxidation, a range of known and novel nonproteinogenic amino acids were isolated as their N-protected derivatives. These novel organoborane homoalanine anion equivalents are generated and transformed under mild conditions and with wide functional group tolerance: electron-rich and -poor aromatic iodides and bromides (and a vinyl bromide) all undergo efficient Suzuki coupling. The extension of this methodology to prepare meso-DAP, R,R-DAP, and R,R-DAS is also described.
Subject(s)
Amino Acids/chemistry , Amino Acids/chemical synthesis , Bromates/chemistry , Chemistry, Organic/methods , Catalysis , Chromatography, Thin Layer , Magnetic Resonance Spectroscopy , Molecular Structure , Palladium/chemistry , StereoisomerismABSTRACT
A versatile route for the synthesis of homochiral alpha-ketoamide analogues of amino acids is described. Incorporation of this functionality into peptide sequences using either solution or solid-phase chemistry resulted in potent inhibitors of the Hepatitis C Virus NS3 proteinase.