Sickle cell disease (SCD) is a prevalent, life-threatening condition with few treatment options, attributed to a heritable mutation in β-hemoglobin. Therapeutic induction of fetal hemoglobin (HbF) with small molecules has been pursued as a treatment to ameliorate many disease complications but with limited success. Herein, we report the discovery of , a novel, potent, and selective molecular glue degrader of the transcription factor WIZ that robustly induces HbF expression as a potential treatment for SCD.
View Article and Find Full Text PDFRedirecting E3 ligases to neo-substrates, leading to their proteasomal disassembly, known as targeted protein degradation (TPD), has emerged as a promising alternative to traditional, occupancy-driven pharmacology. Although the field has expanded tremendously over the past years, the choice of E3 ligases remains limited, with an almost exclusive focus on CRBN and VHL. Here, we report the discovery of novel ligands to the PRY-SPRY domain of TRIM58, a RING ligase that is specifically expressed in erythroid precursor cells.
View Article and Find Full Text PDFMyeloperoxidase (MPO) is a heme-containing peroxidase from phagocytic cells, which plays an important role in the innate immune response. The primary anti-microbial function of MPO is achieved by catalyzing the oxidation of halides by hydrogen peroxide (HO). Upon activation of phagocytes, MPO activity is detectable in both phagosomes and extracellularly, where it can remain or transcytose into interstitial compartments.
View Article and Find Full Text PDFMyeloperoxidase (MPO) activity and subsequent generation of hypochlorous acid has been associated with the killing of host-invading microorganisms (e.g. bacteria, viruses, and fungi).
View Article and Find Full Text PDFMyeloperoxidase (MPO) is a leukocyte-derived redox enzyme that has been linked to oxidative stress and damage in many inflammatory states, including cardiovascular disease. We have discovered aminopyridines that are potent mechanism-based inhibitors of MPO, with significant selectivity over the closely related thyroid peroxidase. 1-((6-Aminopyridin-3-yl)methyl)-3-(4-bromophenyl)urea (Aminopyridine 2) inhibited MPO in human plasma and blocked MPO-dependent vasomotor dysfunction ex vivo in rat aortic rings.
View Article and Find Full Text PDFWe outline a strategy to enable non-directed Pd(II)-catalyzed C-H functionalization in the presence of Lewis basic heterocycles. In a high-throughput screen of two Pd-catalyzed C-H acetoxylation reactions, addition of a variety of -containing heterocycles is found to cause low product conversion. A pyridine-containing test substrate is selected as representative of heterocyclic scaffolds that are hypothesized to cause catalyst arrest.
View Article and Find Full Text PDFAn optimized and highly efficient synthesis of potent, bioactive N-methyl tubulysin analogues 2 and 4 has been achieved with > 40% overall yields. This synthesis represents a significant improvement over previously reported syntheses of these and related tubulysin analogues. The stereoselective synthesis of the unnatural amino acid tubuvaline is accomplished using tert-butanesulfinamide chemistry.
View Article and Find Full Text PDFTen analogues of tubulysin D were synthesized and assayed against established mammalian cell lines, including cancer cells measuring inhibition of cell growth by an MTT assay. These experiments establish for the first time the essential features for the potent cytotoxicity of tubulysin D. The activities of analogues 2 to 5 demonstrate that numerous modifications may be introduced at the C-terminus of the natural product with only modest loss in activity, while the activities of analogues 6 to 8 suggest that a basic amine must be present at the N-terminus to maintain activity.
View Article and Find Full Text PDFSubstrate activity screening (SAS) is a fragment-based method for the rapid development of novel substrates and their conversion into non-peptidic inhibitors of Cys and Ser proteases. The method consists of three steps: (i) a library of N-acyl aminocoumarins with diverse, low-molecular-weight N-acyl groups is screened to identify protease substrates using a simple fluorescence-based assay; (ii) the identified N-acyl aminocoumarin substrates are optimized by rapid analog synthesis and evaluation; and (iii) the optimized substrates are converted into inhibitors by direct replacement of the aminocoumarin with known mechanism-based pharmacophores. This protocol describes a general procedure for the solid-phase synthesis of a library of N-acyl aminocoumarin substrates and the screening procedure to identify weak binding substrates.
View Article and Find Full Text PDFThe first total synthesis of tubulysin D is reported. The development and application of new tert-butanesulfinamide methods allowed for rapid syntheses of the tubuvaline and tubuphenylalanine fragments. Most significantly, a route was devised and implemented to introduce and carry forward the highly labile N,O-acetal functionality.
View Article and Find Full Text PDFThe substrate activity screening method, a substrate-based fragment identification and optimization method for the development of enzyme inhibitors, was previously applied to cathepsin S to obtain low nanomolar 1,4-disubstituted-1,2,3-triazole-based aldehyde inhibitors (Wood, W. J. L.
View Article and Find Full Text PDFAddition of lithium acetylides prepared from 1-pentyne, phenylacetylene, and trimethylsilylacetylene to diverse N-tert-butanesulfinyl ketimines affords a range of alpha,alpha-dibranched propargyl sulfinamides in generally good yields (up to 87%) and with high diastereoselectivities (up to >99:1). Acidic cleavage of the tert-butanesulfinyl group provides the free alpha,alpha-dibranched propargylamines.
View Article and Find Full Text PDFA new fragment-based method for the rapid development of novel and distinct classes of nonpeptidic protease inhibitors, Substrate Activity Screening (SAS), is described. This method consists of three steps: (1) a library of N-acyl aminocoumarins with diverse, low molecular weight N-acyl groups is screened to identify protease substrates using a simple fluorescence-based assay, (2) the identified N-acyl aminocoumarin substrates are optimized by rapid analogue synthesis and evaluation, and (3) the optimized substrates are converted to inhibitors by direct replacement of the aminocoumarin with known mechanism-based pharmacophores. The SAS method was successfully applied to the cysteine protease cathepsin S, which is implicated in autoimmune diseases.
View Article and Find Full Text PDF