Synthesis of α-Aryl Secondary Amides via Nickel-Catalyzed Reductive Coupling of Redox-Active Esters
作者:Alexis L. Gabbey、Nicholas W. M. Michel、Jonathan M. E. Hughes、Louis-Charles Campeau、Sophie A. L. Rousseaux
DOI:10.1021/acs.orglett.2c00918
日期:2022.5.6
The transition-metal-catalyzed α-arylation of secondary amides remains a synthetic challenge due to the presence of a free N–H bond. We report a strategy to synthesize secondary α-aryl amides via a Ni-catalyzed reductive arylation of redox-active N-hydroxyphthalimide (NHP) esters of malonic acid half amides. This transformation proceeds under mild conditions and displays excellent chemoselectivity
Targeting the Src Homology 2 (SH2) Domain of Signal Transducer and Activator of Transcription 6 (STAT6) with Cell-Permeable, Phosphatase-Stable Phosphopeptide Mimics Potently Inhibits Tyr641 Phosphorylation and Transcriptional Activity
作者:Pijus K. Mandal、Pietro Morlacchi、J. Morgan Knight、Todd M. Link、Gilbert R. Lee、Roza Nurieva、Divyendu Singh、Ankur Dhanik、Lydia Kavraki、David B. Corry、John E. Ladbury、John S. McMurray
DOI:10.1021/acs.jmedchem.5b01321
日期:2015.11.25
Signal transducer and activator of transcription 6 (STAT6) transmits signals from cytokines IL-4 and IL-13 and is activated in allergic airway disease. We are developing phosphopeptide mimetics targeting the SH2 domain of STAT6 to block recruitment to phosphotyrosine residues on IL-4 or IL-13 receptors and subsequent Tyr641 phosphorylation to inhibit the expression of genes contributing to asthma. Structure-affinity relationship studies showed that phosphopeptides based on Tyr631 from IL-4R alpha bind with weak affinity to STAT6, whereas replacing the pY+3 residue with simple aryl and alkyl amides resulted in affinities in the mid to low nM range. A set of phosphatase-stable, cell-permeable prodrug analogues inhibited cytokine-stimulated STAT6 phosphorylation in both Beas-2B human airway cells and primary mouse T-lymphocytes at concentrations as low as 100 nM. IL-13-stimulated expression of CCL26 (eotaxin-3) was inhibited in a dose-dependent manner, demonstrating that targeting the SH2 domain blocks both phosphorylation and transcriptional activity of STAT6.
Synthesis and in Vitro Evaluation of a Peptidomimetic Inhibitor Targeting the Src Homology 2 (SH2) Domain of STAT6
作者:Pietro Morlacchi、Pijus K. Mandal、John S. McMurray
DOI:10.1021/ml4003919
日期:2014.1.9
An improved synthesis of a phosphopeptidomimetic prodrug targeting the Src Homology 2 (SH2) domain of signal transducer and activator of transcription 6 (STAT6) is reported. In our convergent methodology, we employed a phosphotyrosine surrogate active ester harboring pivaloyloxymethyl groups, which efficiently coupled to tert-butylglycinyl proline diarylamide. Biological evaluation of 1 has not been