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Molecules (Basel, Switzerland) Nov 2022Antimicrobial resistance is on the rise, and there aren't enough new treatments to combat it. This might send the modern world back to the pre-antibiotic age. The...
Antimicrobial resistance is on the rise, and there aren't enough new treatments to combat it. This might send the modern world back to the pre-antibiotic age. The molecular hybrids of pyrazolo[3,4-]pyridine and triazole have been designed, synthesized, and analyzed for their drug-like molecule nature and in vitro analyses for their inhibition potentials against and . The compounds and have been identified as the high potential molecules in this series based on in vitro experiments. Compound has zone of inhibition values of 15 ± 0.82 mm and 14 ± 0.7 mm, whilst compound has zone of inhibition values of 18 ± 0.95 mm and 16 ± 0.82 mm against and , respectively. MIC and MIB values for compounds and against and are 0.25 and 0.5, respectively.
Topics: Triazoles; Microbial Sensitivity Tests; Staphylococcus aureus; Anti-Bacterial Agents; Pyridines; Klebsiella pneumoniae; Structure-Activity Relationship
PubMed: 36364469
DOI: 10.3390/molecules27217647 -
Yakugaku Zasshi : Journal of the... 2019New meta-arylene ethynylene foldamers were developed by employing pyridine and phenol units. These demonstrated interesting properties related to the hydrogen-bonding... (Review)
Review
New meta-arylene ethynylene foldamers were developed by employing pyridine and phenol units. These demonstrated interesting properties related to the hydrogen-bonding behavior of the arylene units. Pyridine-acetylene-phenol foldamers showed improved saccharide recognition abilities compared with pyridine-acetylene foldamers with no phenol units. Solid-liquid extraction could be achieved due to the strong binding. Hydrocarbon stapling by alkene metathesis under templation was attempted, and the helical structure was efficiently stabilized. Phenol-acetylene oligomers spontaneously formed helical structures via intramolecular hydrogen bonding. The helical sense could be biased by adding chiral amines.
Topics: Acetylene; Alkenes; Glucose; Hydrocarbons; Hydrogen Bonding; Macromolecular Substances; Molecular Conformation; Monosaccharides; Organic Chemistry Phenomena; Phenol; Pyridines; Solid Phase Extraction
PubMed: 30930394
DOI: 10.1248/yakushi.18-00179-2 -
Molecules (Basel, Switzerland) Oct 2018An efficient Ag/pyridine co-mediated oxidative arylthiocyanation of activated alkenes via radical addition/cyclization cascade process was developed. This reaction could...
An efficient Ag/pyridine co-mediated oxidative arylthiocyanation of activated alkenes via radical addition/cyclization cascade process was developed. This reaction could be carried out under mild conditions to provide biologically interesting 3-alkylthiocyanato-2-oxindoles in good to excellent yields. Mechanistic studies suggested a unique NCS• radical addition path and clarified the dual roles of catalytic pyridine as base and crucial ligand to accelerate the oxidation of Ag(I) to Ag(II), which is likely oxidant responsible for the formation of NCS• radical. These mechanistic results may impact the design and refinement of other radical based reactions proceeding through catalytic oxidations mediated by Ag(I)-pyridine/persulfate. The chemical versatility of thiocyanate moiety was also highlighted via SCN-tailoring chemistry in post-synthetic transformation for new S-C(sp³/sp²/sp), S-P, and S-S bonds constructions. The protocol provides an easy access to many important bioisosteres in medicinal chemistry and an array of sulfur-containing 2-oxindoles that are difficult to prepare by other approaches.
Topics: Alkenes; Magnetic Resonance Spectroscopy; Molecular Structure; Oxidation-Reduction; Pyridines; Silver; Thiocyanates
PubMed: 30360416
DOI: 10.3390/molecules23102727 -
Scientific Reports Feb 2017Direct Electron Transfer biosensors, facilitating direct communication between the biomolecule of interest and electrode surface, are preferable compared to enzymatic...
Direct Electron Transfer biosensors, facilitating direct communication between the biomolecule of interest and electrode surface, are preferable compared to enzymatic and mediator based sensors. Although hemoglobin (Hb) contains four redox active iron centres, direct detection is not possible due to inaccessibility of iron centres and formation of dimers, blocking electron transfer. Through the coordination of iron with aza-heterocyclic receptors - pyridine and imidazole - we report a cost effective, highly sensitive and simple electrochemical Hb sensor using cyclic voltammetry and chronoamperometry. The receptor can be either in the form of liquid micro-droplet mixed with blood or dry chemistry embedded in paper membrane on top of screen printed carbon electrodes. We demonstrate excellent linearity and robustness against interference using clinical samples. A truly point of care technology is demonstrated by integrating disposable test strips with handheld reader, enabling finger prick to result in less than a minute.
Topics: Aza Compounds; Biosensing Techniques; Carbon; Electrochemical Techniques; Electrodes; Electron Transport; Electrons; Hemoglobins; Humans; Imidazoles; Iron; Pyridines; Reagent Strips; Receptors, Artificial; Sensitivity and Specificity
PubMed: 28169325
DOI: 10.1038/srep42031 -
Molecules (Basel, Switzerland) Dec 2016Nitrogen-containing pyridine and quinoline are outstanding platforms on which excellent ionophores and sensors for metal ions can be built. Steric and stereochemical... (Review)
Review
Nitrogen-containing pyridine and quinoline are outstanding platforms on which excellent ionophores and sensors for metal ions can be built. Steric and stereochemical effects can be used to modulate the affinity and selectivity of such ligands toward different metal ions on the coordination chemistry front. On the signal transduction front, such effects can also be used to modulate optical responses of these ligands in metal sensing systems. In this review, steric modulation of achiral ligands and stereochemical modulation in chiral ligands, especially ionophores and sensors for zinc, copper, silver, and mercury, are examined using published structural and spectral data. Although it might be more challenging to construct chiral ligands than achiral ones, isotropic and anisotropic absorption signals from a single chiroptical fluorescent sensor provide not only detection but also differentiation of multiple analytes with high selectivity.
Topics: Ionophores; Ligands; Metals; Pyridines; Quinolines; Stereoisomerism
PubMed: 27916967
DOI: 10.3390/molecules21121647 -
Applied and Environmental Microbiology Jul 2020Pyridine and its derivatives constitute the majority of heterocyclic aromatic compounds that occur largely as a result of human activities and contribute to...
Pyridine and its derivatives constitute the majority of heterocyclic aromatic compounds that occur largely as a result of human activities and contribute to environmental pollution. It is known that they can be degraded by various bacteria in the environment; however, the degradation of unsubstituted pyridine has not yet been completely resolved. In this study, we present data on the pyridine catabolic pathway in sp. strain 68b at the level of genes, enzymes, and metabolites. The gene cluster, responsible for the degradation of pyridine, was identified in a catabolic plasmid, p2MP. The pathway of pyridine metabolism consisted of four enzymatic steps and ended by the formation of succinic acid. The first step in the degradation of pyridine proceeds through a direct ring cleavage catalyzed by a two-component flavin-dependent monooxygenase system, encoded by (pyridine monooxygenase) and genes. The genes , , and were found to encode ()--(4-oxobut-1-enyl)formamide dehydrogenase, amidohydrolase, and succinate semialdehyde dehydrogenase, respectively. These enzymes participate in the subsequent steps of pyridine degradation. The metabolites of these enzymatic reactions were identified, and this allowed us to reconstruct the entire pyridine catabolism pathway in sp. 68b. The biodegradation pathway of pyridine, a notorious toxicant, is relatively unexplored, as no genetic data related to this process have ever been presented. In this paper, we describe the plasmid-borne gene cluster, which includes the complete set of genes responsible for the degradation of pyridine. A key enzyme, the monooxygenase PyrA, which is responsible for the first step of the catabolic pathway, performs an oxidative cleavage of the pyridine ring without typical activation steps such as reduction or hydroxylation of the heterocycle. This work provides new insights into the metabolism of -heterocyclic compounds in nature.
Topics: Arthrobacter; Biodegradation, Environmental; Genes, Bacterial; Multigene Family; Pyridines
PubMed: 32471913
DOI: 10.1128/AEM.00902-20 -
Sheng Wu Gong Cheng Xue Bao = Chinese... Mar 2023Biodegradation of pyridine pollutant by microorganisms is one of the economical and effective methods to solve the environmental pollution of pyridine under high...
Biodegradation of pyridine pollutant by microorganisms is one of the economical and effective methods to solve the environmental pollution of pyridine under high salinity conditions. To this end, screening of microorganisms with pyridine degradation capability and high salinity tolerance is an important prerequisite. In this paper, a salt-resistant pyridine degradation bacterium was isolated from the activated sludge of Shanxi coking wastewater treatment plant, and identified as a bacterium belonging to on the basis of colony morphology and 16S rDNA gene phylogenetic analysis. Salt tolerance experiment showed that strain LV4 could grow and degrade pyridine with the initial concentration of 500 mg/L completely in 0%-6% saline environment. However, when the salinity was higher than 4%, strain LV4 grew slowly and the degradation time of pyridine by strain LV4 was significantly prolonged. Scanning electron microscopy showed that the cell division of strain LV4 became slower, and more granular extracellular polymeric substance (EPS) was induced to secrete in high salinity environment. When the salinity was not higher than 4%, strain LV4 responded to the high salinity environment mainly through increasing the protein content in EPS. The optimum conditions for pyridine degradation by strain LV4 at 4% salinity were 30 ℃, pH 7.0 and 120 r/min (DO 10.30 mg/L). Under these optimal conditions, strain LV4 could completely degrade pyridine with an initial concentration of 500 mg/L at a maximum rate of (29.10±0.18) mg/(L·h) after 12 h adaptation period, and the total organic carbon (TOC) removal efficiency reached 88.36%, indicating that stain LV4 has a good mineralization effect on pyridine. By analyzing the intermediate products in pyridine degradation process, it was speculated that strain LV4 achieved pyridine ring opening and degradation mainly through two metabolic pathways: pyridine-ring hydroxylation and pyridine-ring hydrogenation. The rapid degradation of pyridine by strain LV4 in high salinity environment indicates its application potential in the pollution control of high salinity pyridine environment.
Topics: Rhodococcus; Phylogeny; Extracellular Polymeric Substance Matrix; Sewage; Biodegradation, Environmental; Pyridines
PubMed: 36994582
DOI: 10.13345/j.cjb.220822 -
Molecules (Basel, Switzerland) Aug 2021Synthetic heterocyclic compounds have incredible potential against different diseases; pyridines, phenolic compounds and the derivatives of azo moiety have shown... (Review)
Review
Synthetic heterocyclic compounds have incredible potential against different diseases; pyridines, phenolic compounds and the derivatives of azo moiety have shown excellent antimicrobial, antiviral, antidiabetic, anti-melanogenic, anti-ulcer, anticancer, anti-mycobacterial, anti-inflammatory, DNA binding and chemosensing activities. In the present review, the above-mentioned activities of the nitrogen-containing heterocyclic compounds (pyridines), hydroxyl (phenols) and azo derivatives are discussed with reference to the minimum inhibitory concentration and structure-activity relationship, which clearly indicate that the presence of nitrogen in the phenyl ring; in addition, the hydroxyl substituent and the incorporation of a diazo group is crucial for the improved efficacies of the compounds in probing different diseases. The comparison was made with the reported drugs and new synthetic derivatives that showed recent therapeutic perspectives made in the last five years.
Topics: Azo Compounds; Imaging, Three-Dimensional; Phenols; Pyridines
PubMed: 34443460
DOI: 10.3390/molecules26164872 -
International Journal of Nanomedicine 2019Aiming to produce pyridine azo disperse dyes with good fastness properties and promising antimicrobial activity, a number of novel systems of polyfunctionalized pyridine...
AIM
Aiming to produce pyridine azo disperse dyes with good fastness properties and promising antimicrobial activity, a number of novel systems of polyfunctionalized pyridine azo dyes and their selenium nanoparticles (SeNPs) were synthesized.
MATERIALS AND METHODS
The synthesized products were formed by the reaction of diazotized aniline derivatives or diazotized amino antipyrene with any of dibenzoyl methane or benzoyl acetone and cyanoacetamide in boiling ethanolic sodium ethoxide. The structures of the newly synthesized compounds were elucidated by elemental analysis and spectral data. Moreover, (SeNPs) of the pyridine azo disperse dyes were characterized by Ultra-Violet -Visible spectrophotometry, dynamic light scattering , X-ray diffraction, and transmission electron microscope analysis. On the other hand, the synthesized dyes and its (SeNPs) were applied for disperse dyeing of nylon 66 and their fastness properties were measured, such as washing, rubbing, perspiration, and light fastness. In addition, the antimicrobial activities for all the synthesized compounds and for (SeNPs) prepared compounds () were evaluated.
RESULTS
Compounds , and were the most active compounds against all Gram-positive and Gram-negative bacterial species. While, compounds , and were the most active toward some of the bacterial strains (at least two from the selected four strains). Moreover, compounds showed higher activity toward the fungal strain. Also, the minimal inhibitory concentrations for all the most active compounds were determined.
CONCLUSION
Finally, all the (SeNPs) compounds revealed higher activity against bacterial and fungal strains than the other synthesized compounds.
Topics: Anti-Bacterial Agents; Azo Compounds; Bacteria; Fungi; Metal Nanoparticles; Microbial Sensitivity Tests; Pyridines; Selenium; X-Ray Diffraction
PubMed: 31632007
DOI: 10.2147/IJN.S216914 -
Microbiology Spectrum Sep 2021Agrobacterium tumefaciens strain S33 can catabolize nicotine via a hybrid of the pyridine and pyrrolidine pathways. Most of the enzymes involved in this biochemical...
Agrobacterium tumefaciens strain S33 can catabolize nicotine via a hybrid of the pyridine and pyrrolidine pathways. Most of the enzymes involved in this biochemical pathway have been identified and characterized, except for the one catalyzing the oxidation of 6-hydroxy-3-succinoyl-semialdehyde-pyridine to 6-hydroxy-3-succinoylpyridine. Based on a previous genomic and transcriptomic analysis, an open reading frame (ORF) annotated to encode aldehyde dehydrogenase (Ald) in the nicotine-degrading cluster was predicted to be responsible for this step. In this study, we heterologously expressed the enzyme and identified its function by biochemical assay and mass spectrum analysis. It was found that Ald catalyzes the NAD-specific dehydrogenation of 6-hydroxy-3-succinoyl-semialdehyde-pyridine to 6-hydroxy-3-succinoylpyridine. With the nonhydroxylated analog 3-succinoyl-semialdehyde-pyridine (SAP) as a substrate, Ald had a specific activity of 10.05 U/mg at pH 9.0 and apparent values of around 58.68 μM and 0.41 mM for SAP and NAD, respectively. Induction at low temperature and purification and storage in low-salt buffers were helpful to prevent its aggregation and precipitation. Disruption of the gene caused a lower growth rate and biomass of strain S33 on nicotine but not on 6-hydroxy-3-succinoylpyridine. Ald has a broad range of substrates, including benzaldehyde, furfural, and acetaldehyde. Recombinant Escherichia coli cells harboring the gene can efficiently convert furfural to 2-furoic acid at a specific rate of 0.032 mmol min g dry cells, extending the application of Ald in the catalysis of bio-based furan compounds. These findings provide new insights into the biochemical mechanism of the nicotine-degrading hybrid pathway and the possible application of Ald in industrial biocatalysis. Nicotine is one of the major toxic -heterocyclic aromatic alkaloids produced in tobacco plants. Manufacturing tobacco and smoking may lead to some environmental and public health problems. Microorganisms can degrade nicotine by various biochemical pathways, but the biochemical mechanism for nicotine degradation has not been fully elucidated. In this study, we identified an aldehyde dehydrogenase responsible for the oxidation of 6-hydroxy-3-succinoyl-semialdehyde-pyridine to 6-hydroxy-3-succinoylpyridine; this was the only uncharacterized enzyme in the hybrid of the pyridine and pyrrolidine pathways in Agrobacterium tumefaciens S33. Similar to the known aldehyde dehydrogenase, the NAD-specific homodimeric enzyme presents a broad substrate range with high activity in alkaline and low-salt-containing buffers. It can catalyze not only the aldehyde from nicotine degradation but also those of benzaldehyde, furfural, and acetaldehyde. It was found that recombinant Escherichia coli cells harboring the gene could efficiently convert furfural to valuable 2-furoic acid, demonstrating its potential application for enzymatic catalysis.
Topics: Agrobacterium tumefaciens; Bacterial Proteins; Biodegradation, Environmental; Kinetics; NAD; Nicotine; Oxidoreductases; Pyridines; Substrate Specificity; Succinates
PubMed: 34378958
DOI: 10.1128/Spectrum.00924-21