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A method for the synthesis of 4-substituted azabicyclo[3.2.1]octanes from N-tosyl-2-azabicyclo[3.2.1]octa-3,6-diene, a versatile bicyclic heterocycle not commonly used in medicinal chemistry research, is presented. The method uses bromination, followed by Suzuki coupling, and subsequent reduction and deprotection. The desired 4-substituted azabicyclo[3.2.1]octanes were obtained in moderate to high yields. [ABSTRACT FROM AUTHOR]

Abstract: A diastereoselective approach to 3,7,8-trisubstituted cis-decahydroquinolines is described. This ring system forms the core of rings B and E of the norditerpenoid alkaloid methyllycaconitine. This approach starts with a known disubstituted cyclohexene. The remaining carbons are attached via a Knoevenagel condensation followed by an intramolecular lactam formation. The stereochemistry of the substituents is controlled by the cis-substitution of the starting cyclohexene ring. [Copyright &y& Elsevier]

The intramolecular cyclization reactions of aziridines with πnucleophiles can be a useful route to a number of heterocyclic and carbocyclic ring systems. We were particularly interested in the use of this cyclization reaction for the synthesis of 6-azabicyclo[3.2.1]octanes. We report here the development of a new synthesis of the aziridine necessary for the aziridine-π-nucleophile cyclization. We also report on the cyclization of aziridines with three different substitutions on the aziridine nitrogen. We have found that N-diphenylphospinyl and N-H aziridines, while participating in the initial ring-opening reaction, do not lead to the desired bicyclic ring systems. In contrast, a nosyl group on the aziridine nitrogen leads efficiently to the bicyclic ring system and can be readily deprotected. [ABSTRACT FROM AUTHOR]

The development of novel agents for the differentiation of neuronal nicotinic acetylcholine receptors (nAChRs) is important for the treatment of a variety of pathological conditions. We have prepared and evaluated a number of simpler analogues of the norditerpeniod alkaloid methyllycaconitine (MLA) in an effort to understand molecular determinants of nAChR•small molecule interactions. We have previously reported the synthesis and evaluation of a series of ring E analogues of MLA. We report here the optimization of the α3β4* functional activity of this series of compounds through modification of the ester. [Copyright &y& Elsevier]

We have found that aziridines will react with a variety of π-nucleophiles in intramolecular cyclization reactions to produce nitrogen containing core structures found in a variety of bioactive molecules. These cyclizations are more general and facile than corresponding intermolecular reactions. We have examined the effects of ring size, π-nucleophile identity and substitution on this reaction. [Copyright &y& Elsevier]

We have shown that connection of C-2 of an allylsilane to a tethered aziridine ring yields exocyclic γ-amino olefins and desilylated azabicyclo[x.2.1]-systems upon cyclization with BF3·OEt2. Furthermore, manipulation of a specific exocyclic γ-amino olefin provided access to an azabicyclo[3.3.1]nonane. This methodology should be useful for the preparation of natural products and pharmacologically active agents containing these bicyclic heterocyclic systems. [Copyright &y& Elsevier]

We have prepared a 5-aminopentanoic acid nucleobase (APN) dimer and investigated its hybridization capabilities to complementary DNA using both UV melting and NMR techniques. [ABSTRACT FROM AUTHOR]

Demonstrates the total asymmetric synthesis of (-)-yohimbane and ent-alloyohimbane. Novel aziridine-allylsilane cyyclization as key step of the synthesis; Alkylation of tosylamide; Preparation of the lactam by the oxidation of olefin; Conversion of the lactam to (-)-yohimbane and ent-alloyohimbane byy a Bischler-Napieralski reaction.

Demonstrates a general method for the synthesis of nonproteogenic peptides. Acylnitrene route to vicinal amino alcohols; Retrosynthesis of the dipeptides; Intramolecular acylnitrene-mediated aziridination in the formation of the key bicyclic aziridine; Application to the synthesis of (-)-bestatin analogues; Conversion of oxazolidinones to bestatin.

Presents an experiment in which a facile synthesis of differently substituted vicinal amino alcohols is reported. Demonstration which proved that these amino alcohols could be readily prepared from the oxazolidinones by treatment with aqueous base; Results of an experiment in which the authors synthesized a variety of substituted bicyclic aziridine precursors from the corresponding azidoformates using an intramolecular aziridination reaction.

Examines the formation of the scalemic aziridine molecules via the nucleophilic opening of aziridines. Protection of the free hydroxyl as a tert-butyldimethylsilyl ether; Formation of the arizidine ring via a Mitsunobu reaction; Preparation of the aziridine with an R configuration by an alternate route.

Reports on the enantiospecific synthesis of a (1R,3R,5S)-1-amino-3(hydroxymethyl)bicyclo[3.1.0]hexane which could be useful for conversion to corresponding carbocyclic nucleosides. Details and importance of carbocyclic nucleosides; Description of synthesis; Results of synthesis; Discussion of results.

Describes a new method for the synthesis of (1S,3R)-1-amino-3-(hydroxymethyl)cyclopentane. Intramolecular cyclization of an ester enolate onto an activated aziridine; Formation of a substituted pentane ring; Use of arylsulfonate as a substituent; Attempts to produce other forms of cyclopentenes and cyclopentanes; Alterations to improve selectivity of cyclization.

Abstract: A new and a direct synthetic method for the construction of the bicyclo[3.2.1]octane system is envisioned by assembling cyclic allylsilanes with electron-deficient double bonds in a single step via a formal diastereoselective Lewis acid-promoted [3+2] cycloaddition. [Copyright &y& Elsevier]

Abstract: We have studied the conversion of substituted norbornadienes into a substituted 2-azabicyclo[3.2.1]octadiene system via reaction with toluenesulfonyl azide. We have found that both and mono- and disubstituted norbornadienes will undergo the cycloaddition/rearrangement sequence to provide the bicyclooctadiene ring system as a single regioisomer. The 2-azabicyclo[3.2.1]octane ring system can be prepared from the unsaturated 2-azabicyclo[3.2.1]octadiene ring system. [Copyright &y& Elsevier]

Synthetic or natural aza-sugars have shown promise as a therapeutic approach to a variety of disease states by acting as transition state mimics to sugar processing enzymes. Although the synthesis of functionalized bicyclo[3.2.1]octanes has been reported, the procedures are relatively long and low yielding. Herein, we report the facile synthesis of polyhydroxylated 2-azabicyclo[3.2.1]octane that can be selectively functionalized. [ABSTRACT FROM AUTHOR]

We have developed two convenient methods for hydrolysis of 2-oxazolidinones to the corresponding vicinal aminoalcohols. N-Substituted oxazolidinones can be readily hydrolyzed using Dowex 1×8-100 resin. N-Unsubstituted oxazolidinones cannot be hydrolyzed using Dowex resins but are effectively hydrolyzed using polymer supported ethylenediamine. [Copyright &y& Elsevier]

Presents notes in the study of the selective removal of an N-BOC protecting group in the presence of a tert-butyl ester and other acid-sensitive groups. Importance in synthetic sequences; Results of N-BOC removal; Treatment of tert-butyl ester and N-BOC under the same conditions.

A key component of severe COVID-19 is a "cytokine storm" i.e., the excessive expression of unneeded cytokines. Previous studies suggest that SARS-CoV-2 proteins can induce macrophages to secrete pro-inflammatory cytokines; a process that may involve Toll-like receptors (TLRs). Glycogen synthase kinase-3 (GSK-3) has been implicated in TLR signal transduction and a selective GSK-3 inhibitor, termed COB-187, dramatically attenuates cytokine expression induced by the TLR ligand lipopolysaccharide (LPS). In the present study, we provide evidence that the SARS-CoV-2 spike protein (S) and the S2 subunit (S2) induce production of CXCL10 (a chemokine elevated in severe COVID-19) by a human macrophage cell line. Further, we report that two clinically relevant GSK-3 inhibitors and COB-187 attenuate S and S2 protein-induced CXCL10 production. Combined, our observations provide impetus for investigating GSK-3 inhibitors as potential therapeutics for severe COVID-19. • Cytokine storms, the overexpression of unneeded cytokines, are a key aspect of severe COVID-19. • CXCL10, a chemokine, has been shown to be elevated in severe COVID-19. • We provide evidence that the SARS-CoV-2 spike protein induces expression of CXCL10 by a human macrophage cell line. • Two clinically relevant GSK-3 inhibitors, and GSK-3 inhibitor COB-187, attenuate spike protein-induced CXCL10 expression. • These findings provide impetus for exploring GSK-3 inhibitors as potential therapeutics for severe COVID-19. [ABSTRACT FROM AUTHOR]

Abstract: Lung cancer is one of the most common malignancies worldwide. In this Letter, novel MOM-ether analogs of isosteviol were designed and synthesized to be tested for anticancer activities against H1299 lung cancer cell lines. The effects of these derivatives were studied in H1299 human large cell lung carcinoma cells that are null for p53 and compared to normal counterparts NL-20 normal lung epithelial cells. The initial screening of twelve MOM-ether analogs of isosteviol derivatives on H1299 lung cancer cells by MTT assay revealed that two derivatives (an ester and a carbamate) were the most potent in reducing cell viability. The IC50 values for these derivatives were determined to be 14 and 21μM respectively. We compared the cytotoxicity of the best derivatives in H1299 lung cancer cells and NL-20 normal lung epithelial cells. Both derivatives showed lower cytotoxic effects on NL-20 normal lung epithelial cells. Moreover, both derivatives induced apoptosis in H1299 lung cancer cells more than NL-20 normal lung epithelial cells. [Copyright &y& Elsevier]

Abstract: The structure–activity relationship of a series of oxazolidinones binding to T-box riboswitch antiterminator RNA has been investigated. Oxazolidinones differentially substituted at C-5 were prepared and the ligand-induced fluorescence resonance energy transfer (FRET) changes in FRET-labeled antiterminator model RNA were assayed. Both qualitative and quantitative analysis of the structure–activity relationship indicate that hydrogen bonding and hydrophobic properties play a significant role in ligand binding. [Copyright &y& Elsevier]

Abstract: We report here the synthesis of an aziridine tethered to a substituted allylsilane via a substituted tether. These tether-substituted aziridine–allylsilanes cyclize differently upon treatment with BF3·OEt2 than tether-unsubstituted aziridine–allylsilanes and provide a 6-endo-type product. We show that steric interactions between the N-substituent of the aziridine and substitution on the tether can control the product distribution. [Copyright &y& Elsevier]

[Display omitted] Glycogen synthase kinase-3 (GSK-3) has been implicated in numerous pathologies making GSK-3 an attractive therapeutic target. Our group has identified a compound termed COB-187 that is a potent and selective inhibitor of GSK-3. In this study, we probed the mechanism by which COB-187 inhibits GSK-3β. Progress curves, generated via real-time monitoring of kinase activity, indicated that COB-187 inhibition of GSK-3β is time-dependent and subsequent jump dilution assays revealed that COB-187 binding to GSK-3β is reversible. Further, a plot of the kinetic constant (k obs) versus COB-187 concentration suggested that, within the range of concentrations studied, COB-187 binds to GSK-3β via an induced-fit mechanism. There is a critical cysteine residue at the entry to the active site of GSK-3β (Cys-199). We generated a mutant version of GSK-3β wherein Cys-199 was substituted with an alanine. This mutation caused a dramatic decrease in the activity of COB-187; specifically, an IC 50 in the nM range for wild type versus >100 µM for the mutant. A screen of COB-187 against 34 kinases that contain a conserved cysteine in their active site revealed that COB-187 is highly selective for GSK-3 indicating that COB-187′s inhibition of GSK-3β via Cys-199 is specific. Combined, these findings suggest that COB-187 inhibits GSK-3β via a specific, reversible, time and Cys-199-dependent mechanism. [ABSTRACT FROM AUTHOR]

Sepsis is a serious condition that can lead to long-term organ damage and death. At the molecular level, the hallmark of sepsis is the elevated expression of a multitude of potent cytokines, i.e. a cytokine storm. For sepsis involving gram-negative bacteria, macrophages recognize lipopolysaccharide (LPS) shed from the bacteria, activating Toll-like-receptor 4 (TLR4), and triggering a cytokine storm. Glycogen synthase kinase-3 (GSK-3) is a highly active kinase that has been implicated in LPS-induced cytokine production. Thus, compounds that inhibit GSK-3 could be potential therapeutics for sepsis. Our group has recently described a novel and highly selective inhibitor of GSK-3 termed COB-187. In the present study, using THP-1 macrophages, we evaluated the ability of COB-187 to attenuate LPS-induced cytokine production. We found that COB-187 significantly reduced, at the protein and mRNA levels, cytokines induced by LPS (e.g. IL-6, TNF-α, IL-1β, CXCL10, and IFN-β). Further, the data suggest that the inhibition could be due, at least in part, to COB-187 reducing NF-κB (p65/p50) DNA binding activity as well as reducing IRF-3 phosphorylation at Serine 396. Thus, COB-187 appears to be a potent inhibitor of the cytokine storm induced by LPS. [ABSTRACT FROM AUTHOR]

Glycogen synthase kinase-3 (GSK-3) is a multitasking protein kinase that regulates numerous critical cellular functions. Not surprisingly, elevated GSK-3 activity has been implicated in a host of diseases including pathological inflammation, diabetes, cancer, arthritis, asthma, bipolar disorder, and Alzheimer’s. Therefore, reagents that inhibit GSK-3 activity provide a means to investigate the role of GSK-3 in cellular physiology and pathophysiology and could become valuable therapeutics. Finding a potent inhibitor of GSK-3 that can selectively target this kinase, among over 500 protein kinases in the human genome, is a significant challenge. Thus there remains a critical need for the identification of selective inhibitors of GSK-3. In this work, we introduce a novel small organic compound, namely COB-187, which exhibits potent and highly selective inhibition of GSK-3. Specifically, this study 1) utilized a molecular screen of 414 kinase assays, representing 404 unique kinases, to reveal that COB-187 is a highly potent and selective inhibitor of GSK-3; 2) utilized a cellular assay to reveal that COB-187 decreases the phosphorylation of canonical GSK-3 substrates indicating that COB-187 inhibits cellular GSK-3 activity; and 3) reveals that a close isomer of COB-187 is also a selective and potent inhibitor of GSK-3. Taken together, these results demonstrate that we have discovered a region of chemical design space that contains novel GSK-3 inhibitors. These inhibitors will help to elucidate the intricate function of GSK-3 and can serve as a starting point for the development of potential therapeutics for diseases that involve aberrant GSK-3 activity. [ABSTRACT FROM AUTHOR]

Inhibition of interleukin–6 (IL-6) holds significant promise as a therapeutic approach for triple negative breast cancer (TNBC). We previously reported that phenylmethimazole (C10) reduces IL-6 expression in several cancer cell lines. We have identified a more potent derivative of C10 termed COB-141. In the present work, we tested the hypothesis that C10 and COB-141 inhibit TNBC cell expressed IL-6 and investigated the potential for classical IL-6 pathway induced signaling within TNBC cells. A panel of TNBC cell lines (MDA-MB-231, Hs578T, MDA-MB-468) was used. Enzyme linked immunosorbent assays (ELISA) revealed that C10 and COB-141 inhibit MDA-MB-231 cell IL-6 secretion, with COB-141 being ~6.5 times more potent than C10. Therefore, the remainder of the study focused on COB-141 which inhibited IL-6 secretion, and was found, via quantitative real time polymerase chain reaction (QRT-PCR), to inhibit IL-6 mRNA in the TNBC panel. COB-141 had little, if any, effect on metabolic activity indicating that the IL-6 inhibition is not via a toxic effect. Flow cytometric analysis and QRT-PCR revealed that the TNBC cell lines do not express the IL-6 receptor (IL-6Rα). Trans-AM assays suggested that COB-141 exerts its inhibitory effect, at least in part, by reducing NF-κB (p65/p50) DNA binding. In summary, COB-141 is a potent inhibitor of TNBC cell expressed IL-6 and the inhibition does not appear to be due to non-specific toxicity. The TNBC cell lines do not have an intact classical IL-6 signaling pathway. COB-141's inhibitory effect may be due, at least in part, to reducing NF-κB (p65/p50) DNA binding. [ABSTRACT FROM AUTHOR]

The expression of vascular cell adhesion molecule-1 (VCAM-1) on the vascular endothelium can be increased by pro-inflammatory cytokines [e.g. tumor necrosis factor-α (TNF-α)]. VCAM-1 contributes to leukocyte adhesion to, and emigration from, the vasculature which is a key aspect of pathological inflammation. As such, a promising therapeutic approach for pathological inflammation is to inhibit the expression of VCAM-1. Methimazole [3-methyl-1, 3 imidazole-2 thione (MMI)] is routinely used for the treatment of Graves׳ disease and patients treated with MMI have decreased levels of circulating VCAM-1. In this study we used cultured human umbilical vein endothelial cells (HUVEC) to investigate the effect of MMI structural modifications on TNF-α induced VCAM-1 expression. We found that addition of a phenyl ring at the 4-nitrogen of MMI yields a compound that is significantly more potent than MMI at inhibiting 24 h TNF-α-induced VCAM-1 protein expression. Addition of a para methoxy to the appended phenyl group increases the inhibition while substitution of a thiazole ring for an imidazole ring in the phenyl derivatives yields no clear difference in inhibition. Addition of the phenyl ring to MMI appears to increase toxicity as does substitution of a thiazole ring for an imidazole ring in the phenyl MMI derivatives. Each of the compounds reduced TNF-α-induced VCAM-1 mRNA expression and had a functional inhibitory effect, i.e. each inhibited monocytic cell adhesion to 24 h TNF-α-activated HUVEC under fluid flow conditions. Combined, these studies provide important insights into the design of MMI-related anti-inflammatory compounds. [ABSTRACT FROM AUTHOR]

Abstract: The reaction of fused ring aziridines, 3-oxa-1-azabicyclo[3.1.0]hexan-2-ones, with amine nucleophiles can provide either an aminomethyl oxazolidinone or an aziridinyl urea. The amine, reaction solvent, and aziridine substitution have been examined with the aid of computational studies to identify reaction conditions that provide a single product. Polar solvents provided only the aminomethyl oxazolidinone products. Formation of aziridinyl ureas required control of aziridine substitution, solvent, and reactant stoichiometry. [Copyright &y& Elsevier]

As part of an antibacterial drug discovery project, we were interested in preparing bioisosteric replacement analogues of 4,5-disubstituted oxazolidinones. One such isosteric replacement is the imidazolidinone ring system. Here, we report the development of a general synthesis of 1,4-disubstituted imidazolidinones that takes advantage of the base-catalyzed rearrangement of amino-methyl-substituted oxazolidinones. [ABSTRACT FROM AUTHOR]

Abstract: Subtype selective molecules for α4β2 neuronal nicotinic acetylcholine receptors (nAChRs) have been sought as novel therapeutics for nicotine cessation. α4β2 nAChRs have been shown to be involved in mediating the addictive properties of nicotine while other subtypes (i.e., α3β4 and α7) are believed to mediate the undesired effects of potential CNS drugs. To obtain selective molecules, it is important to understand the physiochemical features of ligands that affect selectivity and potency on nAChR subtypes. Here we present novel QSAR/QSSR models for negative allosteric modulators of human α4β2 nAChRs and human α3β4 nAChRs. These models support previous homology model and site-directed mutagenesis studies that suggest a novel mechanism of antagonism. Additionally, information from the models presented in this work was used to synthesize novel molecules; which subsequently led to the discovery of a new selective antagonist of human α4β2 nAChRs. [Copyright &y& Elsevier]

As part of an antibacterial drug discovery project, we were interested in preparing bioisosteric replacement analogues of 4,5-disubstituted oxazolidinones. One such isosteric replacement is the imidazolidinone ring system. Here, we report the development of a general synthesis of 1,4-disubstituted imidazolidinones that takes advantage of the base-catalyzed rearrangement of aminomethyl- substituted oxazolidinones. [ABSTRACT FROM AUTHOR]

The T box antiterminator RNA element is an important component of the T box riboswitch that controls the transcription of vital genes in many Gram-positive bacteria. A series of 1,4-disubstituted 1,2,3-triazoles was screened in a fluorescence-monitored thermal denaturation assay to identify ligands that altered the stability of antiterminator model RNA. Several ligands were identified that significantly increased or decreased the melting temperature ( Tm) of the RNA. The results indicate that this series of triazole ligands can alter the stability of antiterminator model RNA in a structure-dependent manner. [ABSTRACT FROM AUTHOR]

The enantiomers and the cis isomers of two previously studied 4,5-disubstituted oxazolidinones have been synthesized, and their binding to the T-box riboswitch antiterminator model RNA has been investigated in detail. Characterization of ligand affinities and binding site localization indicates that there is little stereospecific discrimination for binding antiterminator RNA alone. This binding similarity between enantiomers is likely due to surface binding, which accommodates ligand conformations that result in comparable ligand-antiterminator contacts. These results have significant implications for T-box antiterminator-targeted drug discovery and, in general, for targeting other medicinally relevant RNA that do not present deep binding pockets. [ABSTRACT FROM AUTHOR]

Abstract: Cancer cells commonly show increased levels of glucose uptake and dependence. A potential strategy for the treatment of cancer may be the inhibition of basal glucose transport. We report here the synthesis of a small library of polyphenolic esters that inhibit basal glucose transport in H1299 lung and other cancer cells. These basal glucose transport inhibitors also inhibit cancer cell growth in H1299 cells, and these two activities appear to be correlated. [Copyright &y& Elsevier]

Abstract: The synthesis of a library of nonactic acid-derived triazoloamide derivatives and their evaluation as antimicrobial agents is described. [Copyright &y& Elsevier]

Abstract: The T box transcription antitermination system is a riboswitch found primarily in Gram-positive bacteria which monitors the aminoacylation of the cognate tRNA and regulates a variety of amino acid-related genes. Novel 4,5-disubstituted oxazolidinones were identified as high affinity RNA molecular effectors that modulate the transcription antitermination function of the T box riboswitch. [Copyright &y& Elsevier]

Abstract: Novel 3,5-disubstituted ring E analogs of methyllycaconitine were prepared and evaluated in nicotinic acetylcholine receptor binding assays. The desired analogs were prepared through the Suzuki–Miyaura cross-coupling reaction of methyl 5-bromo-nicotinate. The Suzuki–Miyaura cross-coupling reactions of pyridines with electron withdrawing substituents have not been extensively described previously. [Copyright &y& Elsevier]

Abstract: We have synthesized and tested a series of novel 3,4,5-tri- and 4,5-disubstituted oxazolidinones for their ability to bind two structurally related T box antiterminator model RNAs. We have found that optimal binding selectivity is found in a small group of 4,5-disubstituted oxazolidinones. [Copyright &y& Elsevier]

Abstract: We have synthesized and tested novel quinuclidinone analogs to assay the effects on H1299 lung cancer cell lines alone or with γ-radiation. We have found two series of quinuclidinone analogs that act as anti-cancer agents. Of these, four interesting analogs significantly decreased cell viability in H1299 lung cancer cell lines. Two derivatives decreased cell proliferation in a dose-dependent fashion alone or in the presence of γ-radiation. Radiosensitization increased when derivative treatment preceded radiation treatment for both derivatives. These preliminary studies show an evidence for both additive and synergistic cytotoxicity for treatment of lung cancer by these novel quinuclidinone analogs. [Copyright &y& Elsevier]

The development of new agents that selectively interact with subtypes of neuronal nicotinic receptors (nAChRs) is of primary importance for the study of physiological processes and pathophysiological conditions involving these receptors. Our laboratory has evidence that simple ring E analogues of methyllycaconitine (MLA) act as antagonists to bovine adrenal α3β4* nAChRs. The following studies were designed to characterize the concentration–response effects of several ring E analogues of MLA in order to assess structural requirements involved with their inhibitory activity on bovine adrenal α3β4* nAChRs. Ring E analogues with various substitutions on the ring E nitrogen were tested for their ability to inhibit nicotinic stimulated adrenal catecholamine release and [3H]epibatidine binding to a bovine adrenal membrane preparation. Several N-alkyl derivatives inhibited secretion with IC50 values in the low micromolar range. The N-phenpropyl analogue was the most potent of the analogues tested (IC50, 11 μM) on adrenal secretion. Competition binding studies suggest a noncompetitive interaction of the analogues with bovine adrenal nAChRs. These studies identify several structural features of ring E analogues of MLA which significantly affect their inhibitory activity on bovine adrenal α3β4* nAChRs. [Copyright &y& Elsevier]

Antibacterial drug resistance is a global health concern that requires multiple solution approaches including development of new antibacterial compounds acting at novel targets. Targeting regulatory RNA is an emerging area of drug discovery. The T-box riboswitch is a regulatory RNA mechanism that controls gene expression in Gram-positive bacteria and is an exceptional, novel target for antibacterial drug design. We report the design, synthesis and activity of a series of conformationally restricted oxazolidinone-triazole compounds targeting the highly conserved antiterminator RNA element of the T-box riboswitch. Computational binding energies correlated with experimentally-derived K d values indicating the predictive capabilities for docking studies within this series of compounds. The conformationally restricted compounds specifically inhibited T-box riboswitch function and not overall transcription. Complex disruption, computational docking and RNA binding specificity data indicate that inhibition may result from ligand binding to an allosteric site. These results highlight the importance of both ligand affinity and RNA conformational outcome for targeted RNA drug design. [ABSTRACT FROM AUTHOR]

Glucose transporters (GLUTs) facilitate glucose uptake and are overexpressed in most cancer cells. Inhibition of glucose transport has been shown to be an effective method to slow the growth of cancer cells both in vitro and in vivo. We have previously reported on the anticancer activity of an ester derived glucose uptake inhibitor. Due to the hydrolytic instability of the ester linkage we have prepared a series of isosteres of the ester moiety. Of all of the isosteres prepared, the amine linkage showed the most promise. Several additional analogues of the amine-linked compounds were also prepared to improve the overall activity. [ABSTRACT FROM AUTHOR]

Abstract: We have shown that the intentional engineering of a natural product biosynthesis pathway is a useful way to generate stereochemically complex scaffolds for use in the generation of combinatorial libraries that capture the structural features of both natural products and synthetic compounds. Analysis of a prototype library based upon nonactic acid lead to the discovery of triazole-containing nonactic acid analogs, a new structural class of antibiotic that exhibits bactericidal activity against drug resistant, Gram-positive pathogens including Staphylococcus aureus and Enterococcus faecalis. [Copyright &y& Elsevier]

The product ratio strongly depends on the polarity of the solvent, cf. [ABSTRACT FROM AUTHOR]

In continuation of an antibacterial discovery project, the ring-opening/rearrangement reaction of bicyclic oxaziridines with primary amines and KOtBu is studied. [ABSTRACT FROM AUTHOR]