Sulfur fluoride exchange (SuFEx) has emerged as the new generation of click chemistry. We report here a SuFEx-enabled, agnostic approach for the discovery and optimization of covalent inhibitors of human neutrophil elastase (hNE). Evaluation of our ever-growing collection of SuFExable compounds toward various biological assays unexpectedly revealed a selective and covalent hNE inhibitor: benzene-1,2-disulfonyl fluoride. Synthetic derivatization of the initial hit led to a more potent agent, 2-(fluorosulfonyl)phenyl fluorosulfate with IC50 0.24 μM and greater than 833-fold selectivity over the homologous neutrophil serine protease, cathepsin G. The optimized, yet simple benzenoid probe only modified active hNE and not its denatured form.

Optimization of small-molecule probes or drugs is a lengthy, challenging and resource-intensive process. Lack of automation and reliance on skilled medicinal chemists is cumbersome in both academic and industrial settings. Here, we demonstrate a high-throughput hit-to-lead process based on the biocompatible SuFEx click chemistry. A modest high-throughput screening hit against a bacterial cysteine protease SpeB was modified with a SuFExable iminosulfur oxydifluoride [RN=S(O)F2] motif, rapidly diversified into 460 analogs in overnight reactions, and the products directly screened to yield drug-like inhibitors with 300-fold higher potency. We showed that the improved molecule is drug-like and biologically active in a bacteria-host coculture. Since these reactions can be performed on a picomole scale to conserve reagents, we anticipate our methodology can accelerate the development of robust biological probes and drug candidates. The introduction of high-throughput screening (HTS) robotics, liquid handler systems, and assay miniaturization have revolutionized screening of bioactive molecules. Relatively inexpensive HTS processes are now routinely used in cell-based and in vitro assays against biomedically relevant targets. Nevertheless, compound optimization is typically necessary to improve target specificity, potency, and stability. Lead optimization relies heavily on medicinal chemists, and extensive time and labor costs remain significant hurdles for probe and drug development. Click chemistry has found broad applications in materials chemistry, chemical biology, and drug development since the concept was first introduced in 1999 1-2. The sulfur(VI) fluoride exchange (SuFEx) represents the most recent set of ideal click chemistry transformations 3. Specifically, aryl fluorosulfates (ArOSO2F) and iminosulfur oxydifluorides (RN=S(O)F2) are readily synthesized using two connective oxyfluoride gases, sulfuryl fluoride (SO2F2) and thionyl tetrafluoride (O=SF4), respectively 4. These two S VI −F motifs have been successfully used as connective linkers in polymer synthesis and for construction of various functional molecules 5-7. Sulfonyl fluoride (RSO2F) and aryl fluorosulfate moieties have been successfully introduced into bioactive molecules in chemical biology and drug discovery 8-11 , especially as covalently binding warheads 12. However, the potential of SuFEx to unite diverse modules using an O=SF4 hub has not been explored in medicinal chemistry. While the copper(I)catalyzed azide-alkyne cycloaddition (CuAAC) reaction has been used in proof-of-concept studies on lead Statistical analysis was performed using one-way ANOVA with Dunnett's multiple comparisons test, *≤ 0.05. Supporting Information Additional texts, figures, and tables are provided. AUTHOR INFORMATION # Authors contributed equally.

Diversity Oriented Clicking (DOC) is a unified click‐approach for the modular synthesis of lead‐like structures through application of the wide family of click transformations. DOC evolved from the concept of achieving “diversity with ease”, by combining classic C−C π‐bond click chemistry with recent developments in connective SuFEx‐technologies. We showcase 2‐Substituted‐Alkynyl‐1‐Sulfonyl Fluorides (SASFs) as a new class of connective hub in concert with a diverse selection of click‐cycloaddition processes. Through the selective DOC of SASFs with a range of dipoles and cyclic dienes, we report a diverse click‐library of 173 unique functional molecules in minimal synthetic steps. The SuFExable library comprises 10 discrete heterocyclic core structures derived from 1,3‐ and 1,5‐dipoles; while reaction with cyclic dienes yields several three‐dimensional bicyclic Diels–Alder adducts. Growing the library to 278 discrete compounds through late‐stage modification was made possible through SuFEx click derivatization of the pendant sulfonyl fluoride group in 96 well‐plates—demonstrating the versatility of the DOC approach for the rapid synthesis of diverse functional structures. Screening for function against MRSA (USA300) revealed several lead hits with improved activity over methicillin.

Plant-derived lignans, consumed daily by most individuals, are thought to protect against cancer and other diseases 1 ; however, their bioactivity requires gut bacterial conversion to enterolignans 2. Here, we dissect a four-species bacterial consortium sufficient for all five reactions in this pathway. A single enzyme (benzyl ether reductase; ber), was sufficient for the first two biotransformations, variable between strains of Eggerthella lenta, critical for enterolignan Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use:

Transcriptional coregulators, which mediate chromatin-dependent transcriptional signaling, represent tractable targets to modulate tumorigenic gene expression programs with small molecules. Genetic loss-of-function studies have recently implicated the transcriptional coactivator, ENL, as a selective requirement for the survival of acute leukemia and highlighted an essential role for its chromatin reader YEATS domain. Motivated by these discoveries, we executed a screen of nearly 300,000 small molecules and identified an amido-imidazopyridine inhibitor of the ENL YEATS domain (IC 50 = 7 μM). Improvements to the initial screening hit were enabled by adopting and expanding upon a SuFEx-based approach to high-throughput medicinal chemistry, ultimately demonstrating that it is compatible with cell-based drug discovery. Through these efforts, we discovered SR-0813, a potent and selective ENL/AF9 YEATS domain inhibitor (IC 50 = 25 nM). Armed with this tool and a first-in-class ENL PROTAC, SR-1114, we detailed the biological response of AML cells to pharmacological ENL disruption for the first time. Most notably, we discovered that ENL YEATS inhibition is sufficient to selectively suppress ENL target genes, including HOXA9/10 , MYB , MYC , and a number of other leukemia proto-oncogenes. Cumulatively, our study establishes YEATS domain inhibition as a viable approach to disrupt the pathogenic function of ENL in acute leukemia and provides the first thoroughly characterized chemical probe for the ENL YEATS domain.