Day: October 12, 2022

Garrett, Mark D.; Scott, Robin; Sheldrake, Gary N.; Dalton, Howard; Goode, Paul published the artcile< Biotransformation of substituted pyridines with dioxygenase-containing microorganisms>, Product Details of C5H4ClNO, the main research area is toluene dioxygenase substituted pyridine oxidation.

A series of 2-, 3- and 4-substituted pyridines was metabolized using the mutant soil bacterium Pseudomonas putida UV4 which contains a toluene dioxygenase (TDO) enzyme. The regioselectivity of the biotransformation in each case was determined by the position of the substituent. 4-Alkylpyridines were hydroxylated exclusively on the ring to give the corresponding 4-substituted 3-hydroxypyridines, while 3-alkylpyridines were hydroxylated stereoselectively on C-1 of the alkyl group with no evidence of ring hydroxylation. 2-Alkylpyridines gave both ring and side-chain hydroxylation products. Chloro- and bromo-substituted pyridines, and pyridine itself, while being poor substrates for P. putida UV4, were converted to some extent to the corresponding 3-hydroxypyridines. These unoptimized biotransformations are rare examples of the direct enzyme-catalyzed oxidation of pyridine rings and provide a novel synthetic method for the preparation of substituted pyridinols. Evidence for the involvement of the same TDO enzyme in both ring and side-chain hydroxylation pathways was obtained using a recombinant strain of Escherichia coli (pKST11) containing a cloned gene for TDO. The observed stereoselectivity of the side-chain hydroxylation process in P. putida UV4 was complicated by the action of an alc. dehydrogenase enzyme in the organism which slowly leads to epimerization of the initial (R)-alc. bioproducts by dehydrogenation to the corresponding ketones followed by stereoselective reduction to the (S)-alcs.

Organic & Biomolecular Chemistry published new progress about Oxidation, regioselective. 96630-88-5 belongs to class pyridine-derivatives, and the molecular formula is C5H4ClNO, Product Details of C5H4ClNO.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Gui, Jianzhou; Cong, Xiaohui; Liu, Dan; Zhang, Xiaotong; Hu, Zhide; Sun, Zhaolin published the artcile< Novel Bronsted acidic ionic liquid as efficient and reusable catalyst system for esterification>, Product Details of C9H13NO3S, the main research area is Bronsted acidic ionic liquid efficient reusable catalyst system esterification.

Under mild conditions and without any addnl. organic solvent, esterification of alcs. by carboxylic acids could be carried out in three new halogen-free Bronsted acidic ionic liquids, 1-(4-sulfonic acid) butyl-3-methylimidazolium hydrogen sulfate, 1-(4-sulfonic acid) butylpyridinium hydrogen sulfate and N-(4-sulfonic acid)butyl triethylammonium hydrogen sulfate. Especially for esterification of ethanol by acetic acid, good conversion rate and high selectivity were obtained, and the liquid esters formed a sep. phase that was decanted. The ionic liquid could be reused after removal of water under vacuum.

Catalysis Communications published new progress about Bronsted acids Role: CAT (Catalyst Use), USES (Uses) (catalyst). 21876-43-7 belongs to class pyridine-derivatives, and the molecular formula is C9H13NO3S, Product Details of C9H13NO3S.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Rasina, Dace; Stakanovs, Georgijs; Kanepe-Lapsa, Iveta; Bobrovs, Raitis; Jaudzems, Kristaps; Jirgensons, Aigars published the artcile< Synthesis of 2-aminopyridopyrimidinones and their plasmepsin I, II, IV inhibition potency>, Reference of 870997-85-6, the main research area is aminopyridopyrimidinone preparation antimalarial SAR.

2-Aminoquinazolin-4(3H)-one-based inhibitors, 2-aminopyrido[2,3-d]-, -[3,2-d]-, and -[4,3-d]pyrimidin-4(3H)-ones beared subpocket-specific substituents at position 7 were prepared and tested for their Plm I, II, IV inhibition potency. The position of the nitrogen atom in 2-aminopyridopyrimidinones played significant role in the inhibitory potency against Plms. Pyrido[2,3-d]pyrimidin-4(3H)-one derivatives showed poor inhibitory potency against Plms I, II, IV irresp. of the substituent at position 7. However, pyrido[4,3-d]pyrimidin-4(3H)-ones and pyrido[3,2-d]pyrimidin-4(3H)-ones were more appropriate scaffolds for Plm inhibitor development. Particularly, 2-amino-7-[4-(3-phenylpropyl)phenyl]-3-[(tetrahydrofuran-2-yl)methyl]pyrido[3,2-d]pyrimidin-4(3H)-one showed very high potency against Plm IV subtype and high selectivity against human aspartic protease, cathepsin D.

Chemistry of Heterocyclic Compounds (New York, NY, United States) published new progress about Antimalarials. 870997-85-6 belongs to class pyridine-derivatives, and the molecular formula is C6H5BrN2O2, Reference of 870997-85-6.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Neranon, Kitjanit; Alberch, Laura; Ramstroem, Olof published the artcile< Design, Synthesis and Self-Assembly of Functional Amphiphilic Metallodendrimers>, HPLC of Formula: 366-18-7, the main research area is self assembly functional amphiphilic metallodendrimers decomplexation; amphiphiles; coordination; metallodendrimers; nanomaterials; self-assembly; supramolecular systems.

A new family of alkynylated, amphiphilic dendrimers consisting of amidoamine linkers connected to 5,5′-functionalized 2,2′-bipyridine cores has been developed and evaluated in the formation of metallodendrimers of different generations and in self-assembly protocols. A convergent synthetic strategy was applied to provide dumbbell-shaped amphiphilic dendrimers, where the 2,2′-bipyridine cores could be coordinated to FeII centers to afford corresponding metallodendrimers. The ability of the metallic- and non-metallic dendritic structures to self-assemble into functional supramol. aggregates were furthermore evaluated in aqueous solution Spherical aggregates with sizes of a few hundred nanometers were generally produced, where controlled disassembly of the metallodendrimers through decomplexation could be achieved.

ChemistryOpen published new progress about Alkynylation. 366-18-7 belongs to class pyridine-derivatives, and the molecular formula is C10H8N2, HPLC of Formula: 366-18-7.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Wandas, M.; Lorenc, J.; Kucharska, E.; Maczka, M.; Hanuza, J. published the artcile< Molecular structure and vibrational spectra of 3 (or 4 or 6)-methyl-5-nitro-2-pyridinethiones: FT-IR, FT-Raman and DFT quantum chemical calculations>, Synthetic Route of 22280-62-2, the main research area is structure vibrational spectra methylnitropyridinethione FT IR Raman DFT quantum.

IR and Raman spectra (RS) of polycrystalline 3-(or 4 or 6)-methyl-5-nitro-2-pyridinethione were measured and analyzed by d. functional theory (DFT) quantum chem. calculations The B3LYP/6-311G(2d,2p) approach was applied for both the thiol and thione tautomers due to the possibility of the formation of these two thiole forms. Mol. structures of these compounds were optimized starting from different mol. geometries of the thiol group and thione group. Two conformations of the 2-mercaptopyridine, trans and cis, were taken into account. The studied compounds appear in the solid state in the thione form. The effect of the hydrogen-bond formation in the studied compounds was considered.

Journal of Raman Spectroscopy published new progress about Conformation. 22280-62-2 belongs to class pyridine-derivatives, and the molecular formula is C6H7N3O2, Synthetic Route of 22280-62-2.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Liu, Jinguo; Yin, Feng; Hu, Jun; Ju, Yong published the artcile< Cu2+-triggered shrinkage of a natural betulin-derived supramolecular gel to fabricate moldable self-supporting gel>, Category: pyridine-derivatives, the main research area is copper ion shrinkage betulin supramol gel moldable self supporting.

Most supramol. gels have a poor ability to be molded into well-defined shapes, preventing them from having the same potential as clay-based and polymeric gels in applications. In this research, a natural betulin-derived bola-type amphiphile Py-BL was synthesized and found to assemble into a supramol. gel with left-handed helixes driven by hydrogen bonding and hydrophobic interactions. Due to the pyridine groups, which were able to coordinate metal ions and were sensitive to acidity, the resulting Py-BL gel exhibited responses to certain metal ions, and Cu2+-selective gel shrinkage was observed, with a contraction of the gel phase in three dimensions. The coordination between Cu2+ and pyridine groups in the ratio of 1 : 4 led to a cross-linked network of nanofibers and decreased the hydrophilic performance of the Py-BL gel, consequently causing the gelling solvent to extrude from the gel network with a macroscopic gel shrinkage. This Cu2+-triggered shrunken gel exhibited an improved rheol. strength and could self-demold spontaneously through the shrinkage process with a precise amount of Cu2+. Using this strategy, we fabricated moldable self-supporting supramol. gels with designed shapes and elec. conductivity It is believed that the Cu2+-triggered shrinkage provides a novel approach to the fabrication of moldable self-supporting supramol. gels at ultralow gel loadings.

Materials Chemistry Frontiers published new progress about Fluorescence. 3731-53-1 belongs to class pyridine-derivatives, and the molecular formula is C6H8N2, Category: pyridine-derivatives.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Karges, Johannes; Heinemann, Franz; Jakubaszek, Marta; Maschietto, Federica; Subecz, Chloe; Dotou, Mazzarine; Vinck, Robin; Blacque, Olivier; Tharaud, Mickael; Goud, Bruno; Vinuelas Zahinos, Emilio; Spingler, Bernhard; Ciofini, Ilaria; Gasser, Gilles published the artcile< Rationally Designed Long-Wavelength Absorbing Ru(II) Polypyridyl Complexes as Photosensitizers for Photodynamic Therapy>, HPLC of Formula: 366-18-7, the main research area is ruthenium polypyridyl complex preparation cancer PDT photosensitizer.

The utilization of photodynamic therapy (PDT) for the treatment of various types of cancer has gained increasing attention over the last decades. Despite the clin. success of approved photosensitizers (PSs), their application is sometimes limited due to poor water solubility, aggregation, photodegradation, and slow clearance from the body. To overcome these drawbacks, research efforts are devoted toward the development of metal complexes and especially Ru(II) polypyridine complexes based on their attractive photophys. and biol. properties. Despite the recent research developments, the vast majority of complexes utilize blue or UV-A light to obtain a PDT effect, limiting the penetration depth inside tissues and, therefore, the possibility to treat deep-seated or large tumors. To circumvent these drawbacks, we present the first example of a DFT guided search for efficient PDT PSs with a substantial spectral red shift toward the biol. spectral window. Thanks to this design, we have unveiled a Ru(II) polypyridine complex that causes phototoxicity in the very low micromolar to nanomolar range at clin. relevant 595 nm, in monolayer cells as well as in 3D multicellular tumor spheroids.

Journal of the American Chemical Society published new progress about Antitumor agents. 366-18-7 belongs to class pyridine-derivatives, and the molecular formula is C10H8N2, HPLC of Formula: 366-18-7.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Domarco, Olaya; Kieler, Claudia; Pirker, Christine; Dinhof, Carina; Englinger, Bernhard; Reisecker, Johannes M.; Timelthaler, Gerald; Garcia, Marcos D.; Peinador, Carlos; Keppler, Bernhard K.; Berger, Walter; Terenzi, Alessio published the artcile< Subcellular Duplex DNA and G-Quadruplex Interaction Profiling of a Hexagonal PtII Metallacycle>, HPLC of Formula: 3731-53-1, the main research area is platinum metallacycle duplex DNA quadruplex interaction; G-quadruplex; SCC; metallacycle; platinum; subcellular localization.

Metal-driven self-assembly afforded a multitude of fascinating supramol. coordination complexes (SCCs) with applications as catalysts, host-guest, and stimuli-responsive systems. However, the interest in the biol. applications of SCCs is only starting to emerge and thorough characterization of their behavior in biol. milieus is still lacking. Herein, we report on the synthesis and detailed in-cell tracking of a Pt2L2 metallacycle. We show that our hexagonal supramol. accumulates in cancer cell nuclei, exerting a distinctive blue fluorescence staining of chromatin resistant to UV photobleaching selectively in nucleolar G4-rich regions. SCC co-localizes with epitopes of the quadruplex-specific antibody BG4 and replaces other well-known G4 stabilizers. Moreover, the photophys. changes accompanying the metallacycle binding to G4s in solution (fluorescence quenching, absorption enhancement) also take place intracellularly, allowing its subcellular interaction tracking.

Angewandte Chemie, International Edition published new progress about Biocompatibility. 3731-53-1 belongs to class pyridine-derivatives, and the molecular formula is C6H8N2, HPLC of Formula: 3731-53-1.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Kim, Haewon; Yoo, Jean; Lim, Yeon-Mi; Kim, Eun-Ji; Yoon, Byung-Il; Kim, Pilje; Yu, Seung Do; Eom, Ig-Chun; Shim, Ilseob published the artcile< Comprehensive pulmonary toxicity assessment of cetylpyridinium chloride using A549 cells and Sprague-Dawley rats>, Application In Synthesis of 123-03-5, the main research area is pulmonary toxicity cetylpyridinium chloride; bronchoalveolar lavage fluid; cetylpyridinium chloride; inhalation toxicity; intratracheal instillation; polymorphonuclear leukocyte; quaternary ammonium compound.

Cetylpyridinium chloride (CPC), a quaternary ammonium compound and cationic surfactant, is used in personal hygiene products such as toothpaste, mouthwash, and nasal spray. Although public exposure to CPC is frequent, its pulmonary toxicity has yet to be fully characterized. Due to high risks of CPC inhalation, we aimed to comprehensively elucidate the in vitro and in vivo toxicity of CPC. The results demonstrated that CPC is highly cytotoxic against the A549 cells with a half-maximal inhibitory concentration (IC50) of 5.79μg/mL. Following CPC exposure, via intratracheal instillation (ITI), leakage of lactate dehydrogenase, a biomarker of cell injury, was significantly increased in all exposure groups. The bronchoalveolar lavage fluid (BALF) anal. showed a significant increase in proinflammatory cytokines interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α levels. ITI of CPC induced focal inflammation of the pulmonary parenchyma in rats lungs. Our study demonstrated that TNF-α was the most commonly secreted proinflammatory cytokine during CPC exposure in both in vitro and in vivo models. Polymorphonuclear leukocytes in the BALF, which are indicators of pulmonary inflammation, significantly increased in a concentration-dependent manner in all in vivo studies including the ITI, acute, and subacute inhalation assays, demonstrating that PMNs are the most sensitive parameters of pulmonary toxicity.

Journal of Applied Toxicology published new progress about Blood urea nitrogen. 123-03-5 belongs to class pyridine-derivatives, and the molecular formula is C21H38ClN, Application In Synthesis of 123-03-5.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Zheng, Qiang; Kurpiewska, Katarzyna; Domling, Alexander published the artcile< SNAr Isocyanide Diversification>, COA of Formula: C6H8N2, the main research area is imino isocyanide preparation; isocyanide amine multicomponent nucleophilic aromatic substitution.

The first-time isocyanide diversification based on nucleophilic aromatic substitution of suitable precursor isocyanides like 1-fluoro-4-isocyano-2-nitrobenzene has been described. The mild conditions allow for easy access to multiple novel isocyanides I (R = morpholin-4-yl, pyrrolidin-1-yl, piperidin-1-yl, etc.) useful in organic synthesis. The resulting isocyanides I are solid and non-noxious, yet react nicely in multicomponent reactions.

European Journal of Organic Chemistry published new progress about Amines Role: RCT (Reactant), RACT (Reactant or Reagent). 3731-53-1 belongs to class pyridine-derivatives, and the molecular formula is C6H8N2, COA of Formula: C6H8N2.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem