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A straightforward site-selective method for the direct carboxylation of resorcinols (3-hydroxyphenol derivatives), phenols, and indoles is reported. The products were obtained in moderate to high yields using supercritical carbon dioxide as an electrophile and solvent under basic conditions. This method offers solvent and metal free conditions without the cumbersome exclusion of air or water with convenient purification.

The folate metabolism enzyme MTHFD2 (methylenetetrahydrofolate dehydrogenase/cyclohydrolase) is consistently overexpressed in cancer but its roles are not fully characterized, and current candidate inhibitors have limited potency for clinical development. In the present study, we demonstrate a role for MTHFD2 in DNA replication and genomic stability in cancer cells, and perform a drug screen to identify potent and selective nanomolar MTHFD2 inhibitors; protein cocrystal structures demonstrated binding to the active site of MTHFD2 and target engagement. MTHFD2 inhibitors reduced replication fork speed and induced replication stress followed by S-phase arrest and apoptosis of acute myeloid leukemia cells in vitro and in vivo, with a therapeutic window spanning four orders of magnitude compared with nontumorigenic cells. Mechanistically, MTHFD2 inhibitors prevented thymidine production leading to misincorporation of uracil into DNA and replication stress. Overall, these results demonstrate a functional link between MTHFD2-dependent cancer metabolism and replication stress that can be exploited therapeutically with this new class of inhibitors. Helleday and colleagues describe a nanomolar MTHFD2 inhibitor that causes replication stress and DNA damage accumulation in cancer cells via thymidine depletion, demonstrating a potential therapeutic strategy in AML tumors in vivo.

Antibiotic resistance caused by beta-lactamase expressing bacteria poses a concern given its global dissemination and proliferation. The emergence of the metallo beta-lactamases is an indefinite health threat toward which current antibiotics have limited clinical efficacy. One solution is to develop metallo beta-lactamase inhibitors (MBLIs) capable of restoring the activity of beta-lactam drugs.This review focuses on potential metallo beta-lactamase inhibitors that have been patented during the period of 2018-2019. The aim is to provide insight into the diverse class of compounds which exhibit a synergistic inhibitory effect on carbapenem-resistant bacteria, when co-administered with a beta-lactam antibiotic.The treatment strategy, of creating a broad-spectrum beta-lactamase inhibitor, is beneficial to the health sector as well as rural communities. Unfortunately, most of the inhibitors lack published data from both

The Nrf2 transcription factor is a key regulator of redox reactions and considered the main target for the multiple sclerosis (MS) drug dimethyl fumarate (DMF). However, exploration of additional Nrf2-activating compounds is motivated, since DMF displays significant off-target effects and has a relatively poor penetrance to the central nervous system (CNS). We de novo synthesized eight vinyl sulfone and sulfoximine compounds (CH-1–CH-8) and evaluated their capacity to activate the transcription factors Nrf2, NFκB, and HIF1 in comparison with DMF using the pTRAF platform. The novel sulfoximine CH-3 was the most promising candidate and selected for further comparison in vivo and later an experimental model for traumatic brain injury (TBI). CH-3 and DMF displayed comparable capacity to activate Nrf2 and downstream transcripts in vitro, but with less off-target effects on HIF1 from CH-3. This was verified in cultured microglia and oligodendrocytes (OLs) and subsequently in vivo in rats. Following TBI, DMF lowered the number of leukocytes in blood and also decreased axonal degeneration. CH-3 preserved or increased the number of pre-myelinating OL. While both CH-3 and DMF activated Nrf2, CH-3 showed less off-target effects and displayed more selective OL associated effects. Further studies with Nrf2-acting compounds are promising candidates to explore potential myelin protective or regenerative effects in demyelinating disorders. Electronic supplementary material The online version of this article (10.1007/s13311-020-00855-0) contains supplementary material, which is available to authorized users.

Many synthetic routes have been explored to make small molecule sulfonimidamides (SIAs), however, its introduction into larger molecules such as oligopeptides has not been studied before. We herein ...

Bedaquiline (BDQ) is the most critical pharmaceutical in the world for treating multidrug-resistant Mycobacterium tuberculosis. Despite it being highly effective, BDQ asymmetric synthesis remains a challenge. Herein, the influence of chiral bases, namely, bis(1-phenylethyl)amine, bisoxazoline, and sparteine on the diastereoselective lithiation reaction to obtain BDQ was investigated. The highest diastereoselective ratio (dr) emerged as 90:10 from the (+)-bis[(R)-1-phenylethyl] lithium amide. This is a significant improvement from the 50:50 dr achieved from the commercial synthesis. Thereafter, the desired (90:10 RS, SR) diastereomeric mixture was easily isolated via a gravity column and subjected to chiral supercritical fluid chromatography (SFC) to access the desired enantiomer (1R, 2S)-BDQ. The advantages of this procedure are enhanced diastereoselection as well as a greener, faster way to achieve excellent enantioseparation (up to 1.0 g scale).

An efficient catalyst-free radical cross-coupling reaction between aromatic aldehydes and sulfoximines was developed. The reaction took place in the presence of N-bromosuccinimide as the radical initiator under microwave irradiation to afford the corresponding acylated sulfoximines in moderate to excellent yields (27 examples). This protocol proved to be rapid, easy to handle, and applicable to a broad scope of substrates.

Herein, we report the synthesis of novel sulfonimidamides (SIAs) based on amino acid building blocks using a one-pot method from tert-butyldiphenylsilyl-protected (TBDPS) sulfonamides, as well as e ...

Chemical proteomics encompasses novel drug target deconvolution methods in which compound modification is not required. Herein we use Thermal Proteome Profiling, Functional Identification of Target by Expression Proteomics and multiplexed redox proteomics for deconvolution of auranofin targets to aid elucidation of its mechanisms of action. Auranofin (Ridaura®) was approved for treatment of rheumatoid arthritis in 1985. Because several clinical trials are currently ongoing to repurpose auranofin for cancer therapy, comprehensive characterization of its targets and effects in cancer cells is important. Together, our chemical proteomics tools confirmed thioredoxin reductase 1 (TXNRD1, EC:1.8.1.9) as a main auranofin target, with perturbation of oxidoreductase pathways as the top mechanism of drug action. Additional indirect targets included NFKB2 and CHORDC1. Our comprehensive data can be used as a proteomic signature resource for further analyses of the effects of auranofin. Here we also assessed the orthogonality and complementarity of different chemical proteomics methods that can furnish invaluable mechanistic information and thus the approach can facilitate drug discovery efforts in general., Graphical abstract Image 1

Sulfonyl fluoride (SF) containing substances are currently attracting enormous attention among practitioners of both chemical biology and synthetic organic chemistry. The groups of Jones and Liskam ...

Herein we report a peculiar organocatalyzed domino-reaction on the carbapenem core structure. As previously reported, 30 mol% of proline yields diazabicyclo[4.2.1]nonane analogues, while we currently report the formation of novel 1,4-diazepin-5-ones from the same starting material in the presence of 100 mol% proline. The inherent chirality of the starting material led to the stereochemical preference of the products with excellent diastereoselectivity (>99 : 1). The diazepinone products were confirmed using X-ray diffraction and 2D-NMR structure elucidation. A plausible mechanism of the re-arrangement, involving an unactivated retro-Dieckmann condensation, is also presented.

Herein, we report the preparation of 1,2,4-thiadiazinane 1,1-dioxides from reaction of β-aminoethane sulfonamides with dichloromethane, dibromomethane and formaldehyde as methylene donors. The β-aminoethane sulfonamides were obtained through sequential Michael addition of amines to α,β-unsaturated ethenesulfonyl fluorides followed by further DBU mediated sulfur(VI) fluoride exchange (SuFEx) reaction with amines at the S–F bond.

Tuberculosis (TB) has been the scourge of the human race for many decades, claiming countless number of lives. This is further complicated by the ability of Mycobacterium tuberculosis to infect extrapulmonary sites, specifically the brain. These extrapulmonary forms of TB are difficult to treat owing to problems associated with drug delivery across the blood–brain barrier. Linezolid (LIN) and clofazimine (CFZ) are two of the more promising anti-TB drugs in recent times. In this study, BALB/c mice were aerosol-infected with M. tuberculosis H37Rv and were treated for 4 weeks with LIN [100 mg/kg body weight (BW)] or CFZ (100 mg/kg BW). Concurrently, it was investigated whether an aerosol TB infection would lead to dissemination of TB bacilli into the brain. Post-treatment brain and lung CFUs were determined together with serum, lung and brain drug concentrations. CFZ displayed a strong bactericidal effect in the lung, whilst LIN had a bacteriostatic effect. Mycobacterium tuberculosis appeared at 2 weeks post-infection in the untreated group (2.38 ± 0.43 log 10 CFU) and more surprisingly at 3 weeks post-infection in the LIN-treated group (1.14 ± 0.99 log 10 CFU). TB bacilli could not be detected in the brains of the CFZ-treated group. To the best of our knowledge, this is the first study showing the appearance of M. tuberculosis in the brain following a murine aerosol TB infection. This study may advocate the use of CFZ as prophylactic treatment to prevent the development of extrapulmonary TB of the central nervous system using a two-pronged approach.

A wide range of microorganisms can infect the central nervous system (CNS). The immune response of the CNS provides limited protection against microbes penetrating the blood-brain barrier. This results in a neurological deficit and sometimes leads to high morbidity and mortality rates despite advanced therapies. For the last two decades, different studies have expanded our understanding of the molecular basis of human neuroinfectious diseases, especially concerning the contributions of mast cell interactions with other central nervous system compartments. Brain mast cells are multifunctional cells derived from the bone marrow and reside in the brain. Their proximity to blood vessels, their role as "first responders" their unique receptors systems and their ability to rapidly release pathogen responsive mediators enable them to exert a crucial defensive role in the host-defense system. This review describes key biological and physiological functions of mast cells, concerning their ability to recognize pathogens via various receptor systems, followed by a coordinated and selective mediator release upon specific interactions with pathogenic stimulating factors. The goal of this review is to direct attention to the possibilities for therapeutic applications of mast cells against bacterial and viral related infections. We also focus on opportunities for future research activating mast cells via adjuvants.

Synthesis and evaluation of structural analogues and isosteres represent a cornerstone methodology among the practitioners of medicinal- and agrochemistry. The sulfonamide functional group represents one of the most important amide isosteres in contemporary drug design, with some 500 compounds that has overcome both the pharmacological and regulatory hurdles that precede studies in humans. We note that mono aza-analogues of sulfonamides, i.e. sulfonimidamides, are rapidly gaining popularity as a novel functional group among molecular architects involved in the design of biologically active compounds for both pharmaceutical- and agrochemical applications. Herein, we review these recent developments with the ambition to showcase the promise of this functional group to the wider chemical community.

The synthesis and evaluation of structural analogues and isosteres are of central importance in medicinal and agricultural chemistry. The sulfonamide functional group represents one of the most important amide isosteres in contemporary drug design, and about 500 such compounds have overcome both the pharmacological and regulatory hurdles that precede studies in humans. The mono aza analogues of sulfonamides, that is, sulfonimidamides, are rapidly gaining popularity as a novel functional group among synthetic chemists involved in the design of biologically active compounds for both pharmaceutical and agrochemical applications. Herein, we review these recent developments to showcase the promise of this functional group.

Herein, we report an operationally simple, ligand- and additive-free oxidative boron-Heck coupling that is compatible with the ethenesulfonyl fluoride functional group. The protocol proceeds at room temperature with chemoselectivity and E-isomer selectivity and offers facile access to a wide range of β-aryl/heteroaryl ethenesulfonyl fluorides from commercial boronic acids. Furthermore, we demonstrate a "one-pot click" reaction to directly transform the products to aryl-substituted β-sultams.

[Image: see text] Herein we demonstrate the expanded utility of a recently described N-trifluoromethylthiolation protocol to sulfonimidamide containing substances. The novel N-trifluoromethylthio sulfonimidamide derivatives thus obtained were evaluated for antibacterial activity against Mycobacterium tuberculosis (M. tb.) and Mycobacterium abscessus and Gram + Ve (Streptococcus aureus, Bacillus subtilis), and Gram – Ve (Escherichia coli, Pseudomonas aeruginosa) bacteria. Two compounds, 13 and 15 showed high antimycobacterial activity with MIC value of 4–8 μg/mL; i.e. comparable to WHO recommended first line antibiotic for TB infection ethambutol. The same compounds were also found to be cytotoxic in HepG2 cells (compound 13 IC(50) = 15 μg/mL; compound 15 IC(50) = 65 μg/mL). A structure activity relationship, using matched pair analysis, gave the unexpected conclusion that the trifluoromethylthio moiety was responsible for the cellular and bacterial toxicity. Given the increasing use of the trifluoromethylthio group in contemporary medicinal chemistry, this observation calls for considerations before implementation of the functionality in drug design.

The Science for Life Laboratory Drug Discovery and Development (SciLifeLab DDD) platform reaches out to Swedish academia with an industry-standard infrastructure for academic drug discovery, supported by earmarked funds from the Swedish government. In this review, we describe the build-up and operation of the platform, and reflect on our first two years of operation, with the ambition to share learnings and best practice with academic drug discovery centers globally. We also discuss how the Swedish Teacher Exemption Law, an internationally unique aspect of the innovation system, has shaped the operation. Furthermore, we address how this investment in infrastructure and expertise can be utilized to facilitate international collaboration between academia and industry in the best interest of those ultimately benefiting the most from translational pharmaceutical research - the patients.

The β-ketoester structural motif continues to intrigue chemists with its electrophilic and nucleophilic sites. Proven to be a valuable tool within organic synthesis, natural product, and medicinal chemistry, reports on chiral β-ketoester molecular skeletons display a steady increase. With the reignition of organocatalysis in the past decade, asymmetric methods available for the synthesis of this structural unit has significantly expanded, making it one of the most exploited substrates for organocatalytic transformations. This review provides comprehensive information on the plethora of organocatalysts used in stereoselective organocatalyzed construction of β-ketoester-containing compounds.

Herein, we report a mild and efficient synthesis of a NODASA-functionalized peptide, which was initiated with a Michael addition reaction between monomethyl fumarate and 1,4,7-triazacyclononane.

Herein, we report an efficient, ligand-free, and additive-free Suzuki-Miyaura coupling that is compatible with the aromatic sulfonyl fluoride functional group. The protocol proceeds at room temperature, on water, and offers facile access to a wide range of biaryl sulfonyl fluorides as bioorthogonal "click" reagents.

Herein, we report a convenient synthesis of aryl-substituted (E)-vinylic NH-sulfoximines via the Horner–Wadsworth–Emmons reaction without the use of protection–deprotection group strategies.

Herein, we report the preparation of 1,2,4-thiadiazinane 1,1-dioxides from reaction of β-aminoethane sulfonamides with dichloromethane, dibromomethane and formaldehyde as methylene donors. The β-aminoethane sulfonamides were obtained through sequential Michael addition of amines to α,β-unsaturated ethenesulfonyl fluorides followed by further DBU mediated sulfur(vi) fluoride exchange (SuFEx) reaction with amines at the S-F bond.

We report a mild and efficient Cu(OAc)2-catalysed protocol for the oxidative C–N cross-coupling of terminal alkynes and N-deprotected sulfonimidamides. The reaction leads to hitherto unknown N-alkynylated sulfonimidamides. Furthermore, we found that the synthesised N-alkynylated sulfonimidamides could undergo silica-gel-mediated hydrolysis to give the corresponding N-acyl-sulfonimidamides, as well as borane–dimethyl sulfide-mediated reduction to give the corresponding N-alkylated sulfonimidamides.

Herein we present the preclinical characterization of novel compounds containing the linear acyl sulfonimidamide functionality. Specifically, we studied the pKa , lipophilicity, in vitro metabolic stability, plasma protein binding, Caco-2 permeability, and aqueous solubility for nine aryl acyl sulfonimidamides. In comparison with widely used carboxylic acid bioisosteres, the acyl sulfonimidamides were found to be less acidic and more lipophilic depending on the substitution pattern in the studied compounds. Importantly, the pKa values (5.9-7.6) were significantly influenced by substituents on the nitrogen atom and the aryl substituents. Moreover, the acyl sulfonimidamides displayed membrane permeabilities ranging from moderate to very high, which correlated with decreased pKa and low to negligible efflux ratios. We foresee that the chiral sulfur center and the two handles for structural diversity of linear acyl sulfonimidamides will offer new opportunities for drug design and for improving the oral bioavailability of acidic drug candidates.

N′-Vinyl sulfonimidamides have been synthesized through a Pd-catalyzed C–N cross coupling between the N′-(imine nitrogen) of N′-deprotected sulfonimidamides and vinyl bromides. The hitherto unreported products were obtained in moderate to excellent yield, and the C–C double bond geometry of the vinylic substrates were retained during the course of reaction. Single crystal X-ray crystallographic analysis confirmed the product structure. Furthermore, we demonstrate that the formed N′-vinyl sulfonimidamides could undergo hydrogenation with Pd–C/H2 to provide N′-alkyl sulfonimidamides.

The Science for Life Laboratory Drug Discovery and Development Platform (SciLifeLab DDD) was established in Stockholm and Uppsala, Sweden, in 2014. It is one of ten platforms of the Swedish national SciLifeLab which support projects run by Swedish academic researchers with large-scale technologies for molecular biosciences with a focus on health and environment. SciLifeLab was created by the coordinated effort of four universities in Stockholm and Uppsala: Stockholm University, Karolinska Institutet, KTH Royal Institute of Technology and Uppsala University, and has recently expanded to other Swedish university locations. The primary goal of the SciLifeLab DDD is to support selected academic discovery and development research projects with tools and resources to discover novel lead therapeutics, either molecules or human antibodies. Intellectual property developed with the help of SciLifeLab DDD is wholly owned by the academic research group. The bulk of SciLifeLab DDD's research and service activities are funded from the Swedish state, with only consumables paid by the academic research group through individual grants.

This present review provides an account on the available synthetic strategies employed to radiolabel commercial and potential bacteria-selective probes for tomographic imaging. These molecular probes encompass leukocytes, antibodies, small molecules, peptides, antibiotics, macrolides, vitamins, oligomers and siderophores. Although this technique has shown to be a valuable tool for non-invasive infection imaging, more development is required to create easy-to-radiolabel kit solutions/procedures for the preparation of the probes.

1. TBA-354 was a promising antitubercular compound with activity against both replicating and static Mycobacterium tuberculosis (M.tb), making it the focal point of many clinical trials conducted by the TB Alliance. However, findings from these trials have shown that TBA-354 results in mild signs of reversible neurotoxicity; this left the TB Alliance with no other choice but to stop the research. 2. In this study, mass spectrometric methods were used to evaluate the pharmacokinetics and spatial distribution of TBA-354 in the brain using a validated liquid chromatography tandem-mass spectrometry (LCMS/MS) and mass spectrometric imaging (MSI), respectively. Healthy female Sprague-Dawley rats received intraperitoneal (i.p.) doses of TBA-354 (20 mg/kg bw). 3. The concentrationtime profiles showed a gradual absorption and tissue penetration of TBA-354 reaching the Cmax at 6 h post dose, followed by a rapid elimination. MSI analysis showed a time-dependent drug distribution, with highest drug concentration mainly in the neocortical regions of the brain. 4. The distribution of TBA-354 provides a possible explanation for the motor dysfunction observed in clinical trials. These results prove the importance of MSI as a potential tool in preclinical evaluations of suspected neurotoxic compounds.

The carbapenem (β-lactam antibiotic) scaffold serves as a useful nucleophile in organocatalytic diarylprolinol trimethylsilyl ether mediated α-heterofunctionalization reactions leading to the formation of diverse products that bear multiple stereocenters in high diastereoselectivity and moderate to good yields.

We report the synthesis of N-(α,β-unsaturated acyl)-substituted sulfonimidamides through a Pd-catalyzed carbonylation protocol, employing sulfonimidamides as nucleophiles using CO gas released ex situ, and vinyl/aryl halides and triflates as reagents. The reaction is general and offers a unique class of products in moderate to good yields for a wide range of substrates and electrophiles; for example, aliphatic, aromatic (electron-donating and -withdrawing groups), heteroaryl, vinyl halides, and triflates. We also expand our initial report on N-aryl–acyl-substituted sulfonimidamide synthesis by employing aryltriflates as electrophiles. Furthermore, we report a surprisingly facile thermolytic Boc deprotection of N-(α,β-unsaturated acyl) sulfonimidamides.

A major hallmark of Alzheimer's disease (AD) is the deposition of amyloid-β (Aβ) peptides in amyloid plaques. Aβ peptides are produced by sequential cleavage of the amyloid precursor protein by the β amyloid cleaving enzyme (BACE) and the γ-secretase (γ-sec) complex. Pharmacological treatments that decrease brain levels of in particular the toxic Aβ42 peptide are thought to be promising approaches for AD disease modification. Potent and selective BACE1 inhibitors as well as γ-sec modulators (GSMs) have been designed. Pharmacological intervention of secretase function is not without risks of either on- or off-target adverse effects. One way of improving the therapeutic window could be to combine treatment on multiple targets, using smaller individual doses and thereby minimizing adverse effect liability. We show that combined treatment of primary cortical neurons with a BACE1 inhibitor and a GSM gives an additive effect on Aβ42 level change compared with the individual treatments. We extend this finding to C57BL/6 mice, where the combined treatment results in reduction of brain Aβ42 levels reflecting the sum of the individual treatment efficacies. These results show that pharmacological targeting of two amyloid precursor protein processing steps is feasible without negatively interfering with the mechanism of action on individual targets. We conclude that targeting Aβ production by combining a BACE inhibitor and a GSM could be a viable approach for therapeutic intervention in AD modification.

We report a highly efficient and mild protocol for Chan–Evans–Lam C–N cross coupling of sulfonimidamides and aryl boronic acids using Cu(OAc)2 as mediator, triethylamine (TEA) as base and acetonitrile as solvent. The reaction proceeds at room temperature and provides high to excellent yields for a variety of boronic acids, allowing N-arylation of both N-protected (N-amine nitrogen) and N-deprotected (N′-imine nitrogen) sulfonimidamides.

Herein, we report the development of mild, organocatalyzed routes to novel β-lactam carbapenem derivatives through Michael type C C bond forming reactions. The same methodology, followed by a retro-Dieckmann reaction, provides a pathway to novel and highly functionalized monobactam derivatives, another class of valuable β-lactam antibiotics.

An efficient diastereoselective synthesis of carbapenem Mannich bases was developed using organocatalysis. This method also provides a route to new highly functionalized diazabicyclo[4.2.1]nonanes of proposed biological significance.

A mild organocatalytic protocol for the syntheses of α,α-disubstituted proline analogues has been developed. The 3-ketoproline scaffold was functionalised using various aromatic nitrostyrenes in the presence of a bifunctional organocatalyst. The resulting quaternary proline derivatives could easily be transformed into α-alkyl-β-hydroxyproline analogues. Furthermore, the methodology could also be applied to the synthesis of 3-ketoproline functionalised peptides with high selectivity and good yields.

Catalysis and Peptide Research Unit, School of Health Sciences, University of KwaZulu-Natal, Durban, South Africa; Antimicrobial Research Unit, School of Health Sciences, University of KwaZulu-Natal, Durban, South Africa; Biomedical Resource Unit, Westville Campus, University of KwaZulu-Natal, Durban, South Africa; Department of Virology, National Health Laboratory Service/University of KwaZulu-Natal, c/o Inkosi Albert Luthuli Central Hospital, Durban, South Africa; Science for Life Laboratory, Drug Discovery and Development Platform, and Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden

Herein we report a facile organocatalytic asymmetric direct cross-aldol reaction of 2-chloroethoxy acetaldehyde with aromatic aldehydes using ( S )-(−)-α,α-diphenyl-2-pyrrolidinemethanol as an organocatalyst to afford anti -2-(2-chloroethoxy)-1-arylpropane-1,3-diols with excellent enantioselectivities (95–98%) and moderate diastereoselectivities (3.5–7:1). The 1,3-diols, obtained after the aldehyde reduction, represent highly functional intermediates that allow for further diversification into both chiral 1,4-dioxanes and morpholines, compounds that frequently display interesting biological activities.