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MSphere Jun 2024is an enteric pathogen that can cause a range of illnesses from mild diarrhea to pseudomembranous colitis and even death. This pathogen often takes advantage of...
UNLABELLED
is an enteric pathogen that can cause a range of illnesses from mild diarrhea to pseudomembranous colitis and even death. This pathogen often takes advantage of microbial dysbiosis provoked by antibiotic use. With the increasing incidence and severity of infections, coupled with high recurrence rates, there is an urgent need to identify innovative therapies that can preserve the healthy state of the gut microbiota. In this study, we screened a microbial metabolite library against . From a collection of 527 metabolites, we identified 18 compounds with no previously identified antimicrobial activity and metabolites that exhibited potent activity against growth. Of these 18 hits, five drugs and three metabolites displayed the most potent anti-. activity and were subsequently assessed against 20 clinical isolates of . These potent agents included ecteinascidin 770 (minimum inhibitory concentration against 50% of isolates [MIC] ≤0.06 µg/mL); 8-hydroxyquinoline derivatives, such as broxyquinoline and choloroquinaldol (MIC = 0.125 µg/mL); ionomycin calcium salt, carbadox, and robenidine hydrochloride (MIC = 1 µg/mL); and dronedarone and milbemycin oxime (MIC = 4 µg/mL). Unlike vancomycin and fidaxomicin, which are the standard-of-care anti-. antibiotics, most of these metabolites showed robust bactericidal activity within 2-8 h with minimal impact on the growth of representative members of the normal gut microbiota. These results suggest that the drugs and microbial metabolite scaffolds may offer alternative avenues to address unmet needs in disease prevention and treatment.
IMPORTANCE
The most frequent infection associated with hospital settings is , which can cause fatal diarrhea and severe colitis, toxic megacolon, sepsis, and leaky gut. Those who have taken antibiotics for other illnesses that affect the gut's healthy microbiota are more susceptible to infection (CDI). Recently, some reports showed higher recurrence rates and resistance to anti-, which may compromise the efficacy of CDI treatment. Our study is significant because it is anticipated to discover novel microbial metabolites and drugs with microbial origins that are safe for the intestinal flora, effective against , and reduce the risk of recurrence associated with CDI.
PubMed: 38940508
DOI: 10.1128/msphere.00273-24 -
Bioinformatics (Oxford, England) Jun 2024Predicting cancer drug response requires a comprehensive assessment of many mutations present across a tumor genome. While current drug response models generally use a...
MOTIVATION
Predicting cancer drug response requires a comprehensive assessment of many mutations present across a tumor genome. While current drug response models generally use a binary mutated/unmutated indicator for each gene, not all mutations in a gene are equivalent.
RESULTS
Here, we construct and evaluate a series of predictive models based on leading methods for quantitative mutation scoring. Such methods include VEST4 and CADD, which score the impact of a mutation on gene function, and CHASMplus, which scores the likelihood a mutation drives cancer. The resulting predictive models capture cellular responses to dabrafenib, which targets BRAF-V600 mutations, whereas models based on binary mutation status do not. Performance improvements generalize to other drugs, extending genetic indications for PIK3CA, ERBB2, EGFR, PARP1, and ABL1 inhibitors. Introducing quantitative mutation features in drug response models increases performance and mechanistic understanding.
AVAILABILITY AND IMPLEMENTATION
Code and example datasets are available at https://github.com/pgwall/qms.
Topics: Humans; Mutation; Neoplasms; Antineoplastic Agents; Imidazoles; Oximes; Computational Biology
PubMed: 38940147
DOI: 10.1093/bioinformatics/btae209 -
The Journal of Organic Chemistry Jun 2024A series of amides, including α-bromo hydroxamates, -alkoxyamides, and -aryloxyamides, were subjected to phosphine-catalyzed ring-opening -selective addition with...
A series of amides, including α-bromo hydroxamates, -alkoxyamides, and -aryloxyamides, were subjected to phosphine-catalyzed ring-opening -selective addition with cyclopropenones, producing various special -unsaturated esters containing oxime ether motif, in moderate to excellent yields, with high regioselectivity, and exclusive -selectivity. The methodology is highly atom-economical, with simple operation procedures, and compatible with a wide substrate scope (more than 44 examples).
PubMed: 38935753
DOI: 10.1021/acs.joc.4c00941 -
Science (New York, N.Y.) Jun 2024The aza Paternò-Büchi reaction is a [2+2]-cycloaddition reaction between imines and alkenes that produces azetidines, four-membered nitrogen-containing heterocycles....
The aza Paternò-Büchi reaction is a [2+2]-cycloaddition reaction between imines and alkenes that produces azetidines, four-membered nitrogen-containing heterocycles. Currently, successful examples rely primarily on either intramolecular variants or cyclic imine equivalents. To unlock the full synthetic potential of aza Paternò-Büchi reactions, it is essential to extend the reaction to acyclic imine equivalents. Here, we report that matching of the frontier molecular orbital energies of alkenes with those of acyclic oximes enables visible light-mediated aza Paternò-Büchi reactions through triplet energy transfer catalysis. The utility of this reaction is further showcased in the synthesis of penaresidin B. Density functional theory computations reveal that a competition between the desired [2+2]-cycloaddition and alkene dimerization determines the success of the reaction. Frontier orbital energy matching between the reactive components lowers transition-state energy (Δ) values and ultimately promotes reactivity.
PubMed: 38935726
DOI: 10.1126/science.adj6771 -
Organic Letters Jun 2024Selenosulfones, as pivotal pharmaceutical molecule frameworks, have become a research hotspot in modern organic synthesis due to their vital need for efficient...
Selenosulfones, as pivotal pharmaceutical molecule frameworks, have become a research hotspot in modern organic synthesis due to their vital need for efficient preparation. Herein, we have developed an iron-catalyzed four-component controllable radical tandem reaction of allenes involving cycloketone oxime esters, 1,4-diazabicyclo[2.2.2]octane bis(sulfur dioxide) adduct (DABSO), and diphenyl diselenides for the synthesis of complex selenosulfones. This is the first case of achieving the 1,2-selenosulfonylation of allenes via a radical process, wherein precise control of radical rates and polarity matching enhance high regioselective conversion. The reaction conditions are ecofriendly and mild with step-efficiency by forming two new C-S bonds and one C-Se bond in one pot. Moreover, the 1,2-selenosulfonylation of allenes can be achieved by replacing cycloketone oxime esters with aryldiazonium tetrafluoroborates in this system.
PubMed: 38934776
DOI: 10.1021/acs.orglett.4c01798 -
Journal of Materials Chemistry. A Jun 2024The preparation of stable large pore aluminophosphate (AlPO) zeotypes offers materials for applications in adsorption and catalysis. Here we report the synthesis of the...
The preparation of stable large pore aluminophosphate (AlPO) zeotypes offers materials for applications in adsorption and catalysis. Here we report the synthesis of the pure AlPO with the SAO topology type (AlPO STA-1) using ,'-diethylbicyclo[2.2.2]oct-7-ene-2,3:5,6-dipyrrolidine (DEBOP) as the organic structure directing agent in the presence of fluoride. The AlPO STA-1 can be rendered microporous (pore volume 0.36 cm g) calcination and the calcined form remains stable in the presence of moisture. The structure of the dehydrated form has been established by Rietveld refinement (tetragonal 4̄2, = 13.74317(10) Å, = 21.8131(5) Å, = 4119.94(16) Å). Multinuclear Al and P MAS NMR, together with 2D COSY and CASTEP NMR calculations, enables resolution and assignment of the signals from all crystallographically distinct Al and P framework sites. Structural elucidation of the as-prepared aluminophosphate-fluoride is more challenging, because of the presence of partially protonated OSDA molecules in the 3D-connected channel system and in particular because the fluoride ions coordinate with positional disorder to some of the Al atoms to give 5-fold as well as tetrahedrally-coordinated framework Al species. These are postulated to occupy Al-F-Al bridging sites, where they are responsible for distortion of the framework [4̄2, = 13.3148(9) Å, = 22.0655(20) Å, = 3911.9(7) Å]. Calcination and removal of fluoride ions and OSDAs allows the framework to expand to its relaxed configuration. The SAO topology type aluminophosphate can also be synthesised with small amounts of Si and Ge in the framework, and these SAPO and GeAPO STA-1 materials are also stable to template removal. IR spectroscopy with CO as a probe at 123 K indicates all have weak-to-mild acidity, increasing in the order AlPO < GeAPO < SAPO. These STA-1 materials have been investigated for their activity in the Beckmann rearrangement of cyclohexanone oxime to ε-caprolactam at 598 K: while all are active, the AlPO form is favoured due to its high selectivity and slow deactivation, both of which are a consequence of its very weak acid strength, which is nevertheless sufficient to catalyse the reaction.
PubMed: 38933527
DOI: 10.1039/d4ta01132e -
Molecules (Basel, Switzerland) Jun 2024A novel coordination polymer [Zn(atyha)] () (Hatyha = 2-(2-aminothiazole-4-yl)-2- hydroxyiminoacetic acid) was constructed by hydrothermal reaction of Zn with Hatyha...
A novel coordination polymer [Zn(atyha)] () (Hatyha = 2-(2-aminothiazole-4-yl)-2- hydroxyiminoacetic acid) was constructed by hydrothermal reaction of Zn with Hatyha ligand. CP exhibits a 2D (4,4)-connected topological framework with Schläfli symbol of {4·6}, where atyha anions serve as tridentate ligands, bridging with Zn through carboxylate, thiazole and oxime groups. CP displays a strong ligand-based photoluminescence at 390 nm in the solid state, and remains significantly structurally stable in water. Interestingly, it can be utilized as a fluorescent probe for selective and sensitive sensing of Fe, CrO and MnO through the fluorescent turn-off effect with limit of detection (LOD) of 3.66 × 10, 2.38 × 10 and 2.94 × 10 M, respectively. Moreover, the efficient recyclability for detection of Fe and CrO is better than that for MnO. The mechanisms of fluorescent quenching involve reversible overlap of UV-Vis absorption bands of the analytes (Fe, CrO and MnO) with fluorescence excitation and emission bands for CP , respectively.
PubMed: 38931007
DOI: 10.3390/molecules29122943 -
Molecules (Basel, Switzerland) Jun 2024Hepatitis B virus (HBV) remains a global health threat. Ribonuclease H (RNase H), part of the virus polymerase protein, cleaves the pgRNA template during viral genome...
Hepatitis B virus (HBV) remains a global health threat. Ribonuclease H (RNase H), part of the virus polymerase protein, cleaves the pgRNA template during viral genome replication. Inhibition of RNase H activity prevents (+) DNA strand synthesis and results in the accumulation of non-functional genomes, terminating the viral replication cycle. RNase H, though promising, remains an under-explored drug target against HBV. We previously reported the identification of a series of -hydroxypyridinedione (HPD) imines that effectively inhibit the HBV RNase H. In our effort to further explore the HPD scaffold, we designed, synthesized, and evaluated 18 novel HPD oximes, as well as 4 structurally related minoxidil derivatives and 2 barbituric acid counterparts. The new analogs were docked on the RNase H active site and all proved able to coordinate the two Mg ions in the catalytic site. All of the new HPDs effectively inhibited the viral replication in cell assays exhibiting EC values in the low μM range (1.1-7.7 μM) with low cytotoxicity, resulting in selectivity indexes (SI) of up to 92, one of the highest reported to date among HBV RNase H inhibitors. Our findings expand the structure-activity relationships on the HPD scaffold, facilitating the development of even more potent anti-HBV agents.
Topics: Hepatitis B virus; Virus Replication; Antiviral Agents; Ribonuclease H; Humans; Structure-Activity Relationship; Molecular Docking Simulation; Catalytic Domain; Oximes; Molecular Structure; Hep G2 Cells; Enzyme Inhibitors
PubMed: 38931006
DOI: 10.3390/molecules29122942 -
Molecules (Basel, Switzerland) Jun 2024In this research, with an aim to develop novel pyrazole oxime ether derivatives possessing potential biological activity, thirty-two pyrazole oxime ethers, including a...
In this research, with an aim to develop novel pyrazole oxime ether derivatives possessing potential biological activity, thirty-two pyrazole oxime ethers, including a substituted pyridine ring, have been synthesized and structurally identified through H NMR, C NMR, and HRMS. Bioassay data indicated that most of these compounds owned strong insecticidal properties against , , , and at a dosage of 500 μg/mL, and some title compounds were active towards at 500 μg/mL. Furthermore, some of the designed compounds had potent insecticidal effects against , , or at 100 μg/mL, with the mortalities of compounds , , , , , , , , , , and against , in particular, all reaching 100%. Even when the dosage was lowered to 20 μg/mL, compound also expressed 50% insecticidal activity against , and compounds , , , , , and displayed more than 60% inhibition rates against . The current results provided a significant basis for the rational design of biologically active pyrazole oxime ethers in future.
Topics: Pyrazoles; Oximes; Insecticides; Animals; Drug Design; Structure-Activity Relationship; Ethers; Molecular Structure; Pyridines; Moths
PubMed: 38930832
DOI: 10.3390/molecules29122767 -
Biomolecules Jun 2024New furan, thiophene, and triazole oximes were synthesized through several-step reaction paths to investigate their potential for the development of central nervous...
New furan, thiophene, and triazole oximes were synthesized through several-step reaction paths to investigate their potential for the development of central nervous systems (CNS)-active and cholinesterase-targeted therapeutics in organophosphorus compound (OP) poisonings. Treating patients with acute OP poisoning is still a challenge despite the development of a large number of oxime compounds that should have the capacity to reactivate acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). The activity of these two enzymes, crucial for neurotransmission, is blocked by OP, which has the consequence of disturbing normal cholinergic nerve signal transduction in the peripheral and CNS, leading to a cholinergic crisis. The oximes in use have one or two pyridinium rings and cross the brain-blood barrier poorly due to the quaternary nitrogen. Following our recent study on 2-thienostilbene oximes, in this paper, we described the synthesis of 63 heterostilbene derivatives, of which 26 oximes were tested as inhibitors and reactivators of AChE and BChE inhibited by OP nerve agents-sarin and cyclosarin. While the majority of oximes were potent inhibitors of both enzymes in the micromolar range, we identified several oximes as BChE or AChE selective inhibitors with the potential for drug development. Furthermore, the oximes were poor reactivators of AChE; four heterocyclic derivatives reactivated cyclosarin-inhibited BChE up to 70%, and - [2-(()-2-(5-(()-(hydroxyimino)methyl)thiophen-2-yl)vinyl)benzonitrile] had a reactivation efficacy comparable to the standard oxime HI-6. analysis and molecular docking studies, including molecular dynamics simulation, connected kinetic data to the structural features of these oximes and confirmed their productive interactions with the active site of cyclosarin-inhibited BChE. Based on inhibition and reactivation and their ADMET properties regarding lipophilicity, CNS activity, and hepatotoxicity, these compounds could be considered for further development of CNS-active reactivators in OP poisoning as well as cholinesterase-targeted therapeutics in neurodegenerative diseases such as Alzheimer's and Parkinson's.
Topics: Oximes; Cholinesterase Inhibitors; Butyrylcholinesterase; Acetylcholinesterase; Humans; Triazoles; Molecular Docking Simulation; Stilbenes; Cholinesterase Reactivators; Organophosphorus Compounds; Central Nervous System
PubMed: 38927082
DOI: 10.3390/biom14060679