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Rising antimicrobial resistance challenges our ability to combat bacterial infections. The problem is acute for tuberculosis (TB), the leading cause of death from infection before COVID-19. Here, we developed a framework for multiple pharmaceutical companies to share proprietary information and compounds with multiple laboratories in the academic and government sectors for a broad examination of the ability of β-lactams to kill Mycobacterium tuberculosis (Mtb). In the TB Drug Accelerator (TBDA), a consortium organized by the Bill & Melinda Gates Foundation, individual pharmaceutical companies collaborate with academic screening laboratories. We developed a higher order consortium within the TBDA in which four pharmaceutical companies (GlaxoSmithKline, Sanofi, MSD, and Lilly) collectively collaborated with screeners at Weill Cornell Medicine, the Infectious Disease Research Institute (IDRI), and the National Institute of Allergy and Infectious Diseases (NIAID), pharmacologists at Rutgers University, and medicinal chemists at the University of North Carolina to screen ∼8900 β-lactams, predominantly cephalosporins, and characterize active compounds. In a striking contrast to historical expectation, 18% of β-lactams screened were active against Mtb, many without a β-lactamase inhibitor. One potent cephaloporin was active in Mtb-infected mice. The steps outlined here can serve as a blueprint for multiparty, intra- and intersector collaboration in the development of anti-infective agents.

A systematic study of the stability of a set of cephalosporins in mouse plasma reveals that cephalosporins lacking an acidic moiety at C-2 may be vulnerable to β-lactam cleavage in mouse plasma.

The historical view of β-lactams as ineffective antimycobacterials has given way to growing interest in the activity of this class against Mycobacterium tuberculosis (Mtb) in the presence of a β-lactamase inhibitor. However, most antimycobacterial β-lactams kill Mtb only or best when the bacilli are replicating. Here, a screen of 1904 β-lactams led to the identification of cephalosporins substituted with a pyrithione moiety at C3’ that are active against Mtb under both replicating and nonreplicating conditions, neither activity requiring a β-lactamase inhibitor. Studies showed that activity against nonreplicating Mtb required the in situ release of the pyrithione, independent of the known class A β-lactamase, BlaC. In contrast, replicating Mtb could be killed both by released pyrithione and by the parent β-lactam. Thus, the antimycobacterial activity of pyrithione-containing cephalosporins arises from two mechanisms that kill mycobacteria in different metabolic states.

Chiral nonracemic N -amino cyclic carbamates (ACCs) are important auxiliaries for certain asymmetric transformations. In the past they have been synthesized from oxazolidinones using methods that require the preparation and use of non-atom economical aminating agents that can be difficult to prepare, and often strong bases. In what follows we describe a mild and operationally simple method for the direct N -amination of oxazolidinones that use NH 2 Cl derived from commercial bleach.

The α-alkylation of ketones is a fundamental synthetic transformation. The development of asymmetric variants of this reaction is important given that numerous natural products, drugs, and related compounds exist as α-functionalized ketones or derivatives thereof. We previously reported our preliminary studies on the development of a new enantioselective ketone α-alkylation procedure using N-amino cyclic carbamate (ACC) auxiliaries. In comparison to other auxiliary-based methods, ACC alkylation offers a number of advantages and is both highly enantioselective and high yielding. Herein, we provide a full account of our studies on the enantioselective ACC ketone α-alkylation method.

A direct approach to access important α-amino phosphonic acids and their derivatives through the formation of C–N bonds is described. Several α-amination reactions of phosphonates that involve electrophilic aminating agents are reviewed. A recent development is highlighted in which an acyclic or cyclic amine is introduced into the α-position of a phosphonate in one step through deprotonative formation of an α-zincate followed by copper-catalyzed amination with an O-acylhydroxylamine.

A direct approach to important α-amino phosphonic acids and its derivatives has been developed by using copper-catalyzed electrophilic amination of α-phosphonate zincates with O-acyl hydroxylamines. This amination provides the first example of CN bond formation which directly introduces acyclic and cyclic amines to the α-position of phosphonates in one step. The reaction is readily promoted at room temperature with as little as 0.5 mol % of catalyst, and demonstrates high efficiency on a broad substrate scope.

Selective α-amination and α-acylation of esters and amides have been developed, employing O-acylhydroxylamines as a dually reactive aminating and acylating reagent. Treatment of zinc enolates with O-acylhydroxylamines provides solely 1,3-dicarbonyl compounds under mild conditions. Introduction of a copper catalyst into the system shifts the reactivity entirely, yielding α-amination products exclusively.

Amines containing either C(sp2)–N or C(sp3)–N bonds are privileged structural motifs that are present in many biologically and pharmaceutically relevant compounds. Traditionally, C–N bonds have been synthesized using nucleophilic amines, with transition metal-mediated aminations providing a powerful method towards this end. The importance of nitrogen-containing compounds continues to drive the development of new C–N bond-forming transformations, therefore making amination reactions using simple and readily available compounds essential to organic synthesis. Electrophilic amination reactions have seen a considerable increase in interest over the past decade as an alternative method for the synthesis of ubiquitous C–N bonds.

A direct approach to access important α-amino phosphonic acids and their derivatives through the formation of C–N bonds is described. Several α-amination reactions of phosphonates that involve electrophilic aminating agents are reviewed. A recent development is highlighted in which an acyclic or cyclic amine is introduced into the α-position of a phosphonate in one step through deprotonative formation of an α-zincate followed by copper-catalyzed amination with an O-acylhydroxylamine.

A broader substrate scope for direct heteroarene amination is achieved by C—H zincation and subsequent Cu-catalyzed electrophilic amination.

The reaction represents the first example of C—N bond formation which directly introduces cyclic and acyclic amines to the α-position of phosphonates in one step.

Treatment of zinc enolates with O-acylhydroxylamines in the presence of a copper catalyst provides α-amination products exclusively [cf.

Heteroaromatic amines are key structural motifs that are widely found in biologically important molecules and medicines; therefore, efficient methods for the synthesis of these important heteroaryl amines are highly valuable. Direct amination of heteroarenes and arenes has been achieved in a one-pot C–H zincation/copper-catalyzed electrophilic amination procedure. This amination method provides an efficient and rapid approach to access a diverse range of heteroaromatic and aromatic amines including those previously inaccessible using C–H amination methods. The mild reaction conditions and good functional-group compatibility demonstrate its great potential for the synthesis of important and complex amines.

A new approach to access o-haloaminoarenes has been achieved by insertion of arynes into a nitrogen–halide bond (N–X). This transition-metal-free transformation displays a broad substrate scope of arynes, good compatibility with functional groups, and high regioselectivity. Representative transformations of the o-haloaminoarenes are described to highlight their utility for rapid access to diversely functionalized aminoarene derivatives.

Reversible acetylation of α-tubulin is an evolutionarily conserved modification in microtubule networks. Despite its prevalence, the physiological function and regulation of microtubule acetylation remain poorly understood. Here we report that macrophages challenged by bacterial lipopolysaccharides (LPS) undergo extensive microtubule acetylation. Suppression of LPS-induced microtubule acetylation by inactivating the tubulin acetyltransferase, MEC17, profoundly inhibits the induction of anti-inflammatory interleukin-10 (IL-10), a phenotype effectively reversed by an acetylation-mimicking α-tubulin mutant. Conversely, elevating microtubule acetylation by inhibiting the tubulin deacetylase, HDAC6, or stabilizing microtubules via Taxol stimulates IL-10 hyper-induction. Supporting the anti-inflammatory function of microtubule acetylation, HDAC6 inhibition significantly protects mice from LPS toxicity. In HDAC6-deficient macrophages challenged by LPS, p38 kinase signalling becomes selectively amplified, leading to SP1-dependent IL-10 transcription. Remarkably, the augmented p38 signalling is suppressed by MEC17 inactivation. Our findings identify reversible microtubule acetylation as a kinase signalling modulator and a key component in the inflammatory response.

A reproducible, sensitive immunoassay for murine interleukin-3 (IL-3) has been developed using two preparations of polyclonal antipeptide antibodies. Rabbits were immunized with the N-terminal peptide 1–29 (IL-3) coupled to KLH and the antibodies were affinity purified on immobilized peptide 1–29 (IL-3). This antibody preparation showed good reactivity with native IL-3, and was used to coat polyvinyl microtiter trays. IL-3 captured by this first antibody was detected by the addition of anti-IL-3 serum (second antibody) raised in sheep against synthetic full length IL-3 (1–140). This test reliably detects IL-3 from every source tested (T cells, WEHI-3B cells, recombinant material from transfected COS 7 cells or murine myeloid FDC-P1 cells transfected with an IL-3 containing retrovirus) with a sensitivity to 2 to 4 U/ml of bioactive IL-3 or about 60 pg synthetic IL-3/ml. The test is performed within 5 to 6 h compared to 2 to 3 d of a standard bioassay.