Heterocyclic Building Blocks-Tetrahydropyran

Cordier, Pierre published the artcileSilver and Bronsted Acid Catalyzed Nazarov-Type Cyclizations To Generate Benzofulvenes, Computed Properties of 27943-46-0, the publication is Angewandte Chemie, International Edition (2009), 48(46), 8757-8760, S8757/1-S8757/34, database is CAplus and MEDLINE.

A general method for the preparation of benzofulvenes from diaryl α-hydroxyallenes is reported. For monosubstituted allenes ZnCl₂ was the best catalysts, whereas for di- and tetrasubstituted allenes AgOTf, TfOH, and H₃PMo₁₂O₄₀ gave better results. When two Ph groups were present, the regioselectivity could be controlled by ortho substituents. The thienyl group proved to be more reactive than Ph groups.

Angewandte Chemie, International Edition published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, Computed Properties of 27943-46-0.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Si-Ahmed, Kahina published the artcileEvaluation of novel amylose and cellulose-based chiral stationary phases for the stereoisomer separation of flavanones by means of nano-liquid chromatography, Category: tetrahydropyran, the publication is Analytica Chimica Acta (2012), 85-94, database is CAplus and MEDLINE.

Three polysaccharide-based chiral stationary phases, Sepapak 1, Sepapak 2 and Sepapak 3 were evaluated in the present work for the stereoisomer separation of a group of 12 flavonoids including flavanones (flavanone, 4′-methoxyflavanone, 6-methoxyflavanone, 7-methoxyflavanone, 2′-hydroxyflavanone, 4′-hydroxyflavanone, 6-hydroxyflavanone, 7-hydroxyflavanone, hesperetin, naringenin) and flavanone glycosides (hesperidin, naringin) by nano-liquid chromatog. (nano-LC). The behavior of these chiral stationary phases (CSPs) towards the selected compounds was studied in capillary columns (100 μm internal diameter (internal diameter)) packed with the above mentioned CSPs using polar organic, reversed and normal elution modes. The influence of nature and composition of the mobile phase in terms of concentration and type of organic modifier, buffer type and water content (reversed phase elution mode) on the enantioresoln. (R_s), retention factor (k) and enantioselectivity (α) was evaluated. Sepapak 3 showed the best chromatog. results in terms of enantioresoln., enantioselectivity and short anal. time, employing a polar organic phase mode. A mixture of methanol/isopropanol (20/80, volume/volume) as mobile phase enabled the chiral separation of eight flavanones with enantioresoln. factor (R_s) in the range 1.15-4.18. The same analytes were also resolved employing reversed and normal phase modes with mixtures of methanol/water and hexane/ethanol at different ratios as mobile phases, resp. Loss in resolution for some compounds, broaden peaks and longer anal. times were observed with these last two chromatog. elution modes. Afterwards, a comparison with the other two CSPs was performed. A lower discrimination ability of Sepapak 1 and Sepapak 2 towards all the studied flavanoids was observed However, Sepapak 1 allowed the separation of naringenin enantiomers and naringin stereoisomers in polar organic phase which were not resolved with the other two CSPs.The nature of the chiral selector is of utmost importance for the resolution of the selected compounds Indeed, significant differences in enantioresoln. among the three tested CSPs were observed With regard to the only few data reported in the literature for the resolution of this class of compounds using polysaccharide-based CSPs by HPLC, the results obtained in this study by nano-LC showed higher (R_s) values and shorter anal. time.

Analytica Chimica Acta published new progress about 69097-99-0. 69097-99-0 belongs to tetrahydropyran, auxiliary class Other Aliphatic Heterocyclic,Benzene,Phenol,Ether,Inhibitor, name is 5,7-Dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chroman-4-one, and the molecular formula is C15H10O2, Category: tetrahydropyran.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Huo, Jianqiang published the artcileFacile synthesis and platinum complexes of 4′,5,5”-trisubstituted-2,2′:6′,2”-terpyridines, SDS of cas: 27943-46-0, the publication is Dalton Transactions (2011), 40(29), 7534-7540, database is CAplus and MEDLINE.

The synthesis of trisubstituted 4′,5,5” terpyridines is described. The strategy begins with synthesis of 2-acetyl-5-bromopyridine (3) from 2,5-dibromopyridine, substitution of the bromine in 3 using a variety of metal-catalyzed reactions and then formation of the terpyridine using the Krohnke reaction. The complexes were prepared by reaction of [Pt(PhCN)₂Cl₂] with the appropriate Ag salt followed by addition of the terpyridyl ligand. The crystal structure of two complexes were determined via x-ray diffraction and the MLCT (metal-to-ligand charge-transfer) emissions determined by UV/visible spectroscopy.

Dalton Transactions published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, SDS of cas: 27943-46-0.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Silva, Thayna F. B. published the artcileEndocyclic Oxygen in 3-Fluorodihydro-2H-pyran-4(3H)-one That Does Not Induce the Gauche Effect, Related Products of tetrahydropyran, the publication is Journal of Physical Chemistry A (2014), 118(32), 6266-6271, database is CAplus and MEDLINE.

2-Fluorocyclohexanone undergoes chair inversion, giving rise to axial and equatorial conformers, with the equatorial form being highly preferred in solution, for example, 87% in chloroform and 93% in methylene chloride. Modifications in the conformational preferences can modify macroscopic properties of 2-fluoro ketones. The introduction of an endocyclic oxygen in 2-fluorocyclohexanone to give 3-fluorodihydro-2H-pyran-4(3H)-one would be expected to create a gauche effect in the axial conformer along with the O-C-C-F moiety, inducing an increase of its population. However, small changes were verified in the conformational populations both in the gas phase and solution because the carbonyl group plays an important role for the hyperconjugation in the equatorial conformer, despite experiencing strong dipolar repulsion with the fluorine atom. These data were obtained theor. and by NMR spectroscopy, while the nature of the interactions governing these conformational shifts were investigated on the basis of natural bond orbital anal.

Journal of Physical Chemistry A published new progress about 624734-19-6. 624734-19-6 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Fluoride,Ketone, name is 3-Fluorodihydro-2H-pyran-4(3H)-one, and the molecular formula is C10H16Br3N, Related Products of tetrahydropyran.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Bjerregaard, Poul published the artcileOrally administered bisphenol A in rainbow trout (Oncorhynchus mykiss): estrogenicity, metabolism, and retention, Computed Properties of 267244-08-6, the publication is Environmental Toxicology and Chemistry (2007), 26(9), 1910-1915, database is CAplus and MEDLINE.

The estrogenic effect of orally administered bisphenol A (BPA) was investigated in a rainbow trout (Oncorhynchus mykiss) test system. Bisphenol A was administered orally to sexually immature rainbow trout every second day for up to 12 d in doses between 1.8 and 258 mg/kg every second day (/2d). Plasma vitellogenin was measured before and during the exposures, and the concentrations of BPA in plasma, liver, and muscle and the plasma concentrations of BPA glucuronic acid (BPAGA) were determined at the end of the experiments Increases in average plasma vitellogenin levels were seen at oral exposure to 24 mg BPA/kg/2d; the most sensitive fish responded to 9.3 mg/kg/2d. At day 12, the 10, 50, and 90% EDs for increase in vitellogenin synthesis were 13, 19, and 25 mg/kg/2d, resp. Bisphenol A could be detected in liver, muscle, and plasma at the end of the exposure, generally in increasing concentrations with increasing doses; liver concentrations generally were higher than muscle concentrations Four to five hours after the last feeding of doses between 3.6 and 24 mg BPA/kg, plasma BPA concentrations ranged between 400 and 1,200 nM, whereas BPAGA concentrations were between 2- and 10-fold higher. The difference between BPA and BPAGA concentrations increased with increasing BPA dose. Bisphenol A showed little tendency to bioaccumulate in rainbow trout; less than 1% of the total amount of BPA administered orally at doses between 1.8 and 258 mg/kg/2d over the 10- or 12-d exptl. period was retained in muscle and liver at 5 or 24 h after the end of the experiments

Environmental Toxicology and Chemistry published new progress about 267244-08-6. 267244-08-6 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Chiral,Carboxylic acid,Benzene,Phenol,Alcohol,Ether,, name is (2S,3S,4S,5R,6S)-3,4,5-Trihydroxy-6-(4-(2-(4-hydroxyphenyl)propan-2-yl)phenoxy)tetrahydro-2H-pyran-2-carboxylic acid, and the molecular formula is C21H24O8, Computed Properties of 267244-08-6.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Ros, Oihana published the artcileSimultaneous enzymatic hydrolysis and extraction of endocrine-disrupting chemicals in fish bile using polyethersulfone polymer, Formula: C21H24O8, the publication is Analytical and Bioanalytical Chemistry (2015), 407(24), 7413-7423, database is CAplus and MEDLINE.

This study describes a new method for the simultaneous extraction and enzymic hydrolysis of alkylphenols, estrogens, bisphenol-A and phthalate metabolite (mono-2-ethylhexyl ester, MEHP) in fish bile using polyethersulfone (PES) polymer as sorptive material. Parameters affecting the hydrolysis (enzyme amount) and extraction (nature of polymeric material, PES desorption solvent nature and time, PES amount and time profile) were optimized. The optimum conditions were fixed as: 5 PES tubes (1.5 cm length × 0.7 mm o.d.) were added to a vessel with 100 μL of sample, 800 μL of ultrapure water, 1.5 mL phosphate buffer (0.1 mol L^-1, pH 6) and 200 μL of β-glucuronidase (1000 U mL^-1) enzyme and the mixture was stirred at 37 °C and 550 rpm for 3 h. Quant. results were obtained after desorption of PES material using 500 μL of Et acetate. The extracts were reconstituted in 250 μL of methanol and analyzed by liquid chromatog.-tandem mass spectrometry, obtaining apparent recoveries in the range of 73-134 % using deuterated compounds surrogates corrections. Relative standard deviations below 27 % were obtained for all target analytes and the method detection limits (MDLs) were in low nanograms per mL level for all the studied compounds, except in the case of MEHP which was detected at higher concentration levels (ng μL^-1) in bile samples that do not allow its MDL determination Bisphenol A (MDL-10.8 ng mL^-1), diethylstilbestrol (MDL-1.4 ng mL^-1) and MEHP (975-2604 ng mL^-1) were detected in gray mullets captured nearby the wastewater treatment plant of Gernika (Biosphere Reserve of Urdaibai).

Analytical and Bioanalytical Chemistry published new progress about 267244-08-6. 267244-08-6 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Chiral,Carboxylic acid,Benzene,Phenol,Alcohol,Ether,, name is (2S,3S,4S,5R,6S)-3,4,5-Trihydroxy-6-(4-(2-(4-hydroxyphenyl)propan-2-yl)phenoxy)tetrahydro-2H-pyran-2-carboxylic acid, and the molecular formula is C21H24O8, Formula: C21H24O8.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Dormeyer, Matthias published the artcileRational design of anticytoadherence inhibitors for Plasmodium falciparum based on the crystal structure of human intercellular adhesion molecule 1, Application of 5,7-Dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chroman-4-one, the publication is Antimicrobial Agents and Chemotherapy (2006), 50(2), 724-730, database is CAplus and MEDLINE.

Adhesion of Plasmodium falciparum-infected erythrocytes (IE) to host endothelium has been associated with pathol. in malaria. Although the interaction with endothelial cells can be complex due to the relatively large number of host receptors available for binding, specific proteins have been identified that are more commonly used than others. For example, binding to intercellular adhesion mol. 1 (ICAM 1) is found frequently in parasites from pediatric cases of malaria. The binding site for P. falciparum-infected erythrocytes on ICAM 1 has been mapped in some detail and is distinct from the site for lymphocyte function-associated antigen 1 (LFA-1). Part of the ICAM 1 binding site for P. falciparum-infected erythrocytes (the DE loop) was used to screen a library of compounds based on its structure (derived from the crystal structure of human ICAM 1). This resulted in the identification of 36 structural mimeotopes as potential competitive inhibitors of binding. One of these compounds, (+)-epigalloyl-catechin-gallate [(+)-EGCG], was found to inhibit IE adhesion to ICAM 1 in a dose-dependent manner with two variant ICAM 1-binding parasite lines, providing the first example of a potential mimeotope-based anticytoadherence inhibitor for Plasmodium falciparum.

Antimicrobial Agents and Chemotherapy published new progress about 69097-99-0. 69097-99-0 belongs to tetrahydropyran, auxiliary class Other Aliphatic Heterocyclic,Benzene,Phenol,Ether,Inhibitor, name is 5,7-Dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chroman-4-one, and the molecular formula is C16H14O6, Application of 5,7-Dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chroman-4-one.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Kavuru, Padmini published the artcileHierarchy of Supramolecular Synthons: Persistent Hydrogen Bonds Between Carboxylates and Weakly Acidic Hydroxyl Moieties in Cocrystals of Zwitterions, Safety of 5,7-Dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chroman-4-one, the publication is Crystal Growth & Design (2010), 10(8), 3568-3584, database is CAplus.

Whereas carboxylic acids are well explored in the context of cocrystals, the same cannot be said about carboxylate moieties. This Cambridge Structural Database (CSD) and exptl. study demonstrates that carboxylate moieties persistently form charge-assisted H-bonds with weakly acidic hydroxyl moieties such as phenols. CSD statistics reveal that 58 of 103 relevant structures exhibit carboxylate-hydroxyl (phenolic) supramol. heterosynthons even in the presence of competing functional groups. The following neutral cocrystal formers sustain 15 new cocrystals of zwitterions and their crystal structures reveal that all exhibit carboxylate-hydroxyl supramol. heterosynthons: citric acid (CIT), L-ascorbic acid (ASC), hesperetin (HES), quercetin (QUE), resveratrol (RES), catechol (CAT), protocatechuic acid (PCA), ferulic acid (FER), ellagic acid (ELA), and gallic acid (GAL). Zwitterions used were betaine (BTN), sarcosine (SAR), di-Me glycine (DMG), baclofen (BAC), nicotinic acid (NAC), and isonicotinic acid (INA). Carboxylate-hydroxyl supramol. heterosynthons were observed as follows: 2-point carboxylate-vicinal diol R²₂ (9) in ASCSAR, ASCNAC, and BTNASC; R⁴₄ (18) between two carboxylate and two catechol moieties in BTNGAL, ELASAR, and ELADMG; CITINA·2H₂O, GALINA·H₂O, and HESNAC (+ and ± forms) exhibit 1-point H-bonds.

Crystal Growth & Design published new progress about 69097-99-0. 69097-99-0 belongs to tetrahydropyran, auxiliary class Other Aliphatic Heterocyclic,Benzene,Phenol,Ether,Inhibitor, name is 5,7-Dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chroman-4-one, and the molecular formula is C16H14O6, Safety of 5,7-Dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chroman-4-one.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics

Naapuri, Janne M. published the artcileArylative Allenol Cyclization via Sequential One-pot Enzyme & Palladium Catalysis, Application In Synthesis of 27943-46-0, the publication is ChemCatChem (2021), 13(2), 763-769, database is CAplus.

The one-pot combination of halogenation biocatalysis and Suzuki-type cross coupling enables the direct arylative cyclization of allenic alcs. with boronic acids. This modular approach to unsaturated five-membered O-heterocycles proceeds in an aqueous emulsion with air as terminal oxidant. Here, the enzymic oxidative activation of simple halide salts acts as traceless ring-closure-inducing event to trigger the subsequent C-C coupling. With the original protocol merging soluble proteins and a homogeneous SPhos-based palladium catalyst as a template, a novel heterogeneous nanobiohybrid was developed. Consisting of an oxidase matrix hosting small spherical palladium nanoparticles, this enzyme-metal hybrid exhibits catalytic competence for both the biocyclization as well as the C-C bond-forming cross coupling, underlining the potential of this new techniques for streamlining chemoenzymic approaches.

ChemCatChem published new progress about 27943-46-0. 27943-46-0 belongs to tetrahydropyran, auxiliary class Tetrahydropyran,Alkynyl,Ether, name is 2-((2-Methylbut-3-yn-2-yl)oxy)tetrahydro-2H-pyran, and the molecular formula is C10H16O2, Application In Synthesis of 27943-46-0.

Referemce:
https://en.wikipedia.org/wiki/Tetrahydropyran,
Tetrahydropyran – an overview | ScienceDirect Topics