Tag: M.W:300-400

14187-32-7, An article , which mentions 14187-32-7, molecular formula is C20H24O6. The compound – Dibenzo-18-crown-6 played an important role in people’s production and life.

The Effect of Crown Ethers, Tetraalkylammonium Salts, and Polyoxyethylene Amphiphiles on Pirarubicin Incorporation in K562 Resistant Cells

The basic distinguishing feature of all cells expressing functional P-glycoprotein-multidrug resistance (P-gp-MDR) is a decrease in steady-state accumulation drug levels as compared to drug-sensitive controls. In an attempt to identify mechanism(s) by which MDR can be circumvented, we examined the cellular accumulation, in resistant cells, of 4′-O-tetrahydropyranyl-doxorubicin (pirarubicin) alone and in conjunction with various molecules belonging to three different classes: the crown ethers, the tetraalkylammonium salts, and the polyoxyethylene amphiphiles. The present study was performed using a spectrofluorometric method which enabled us to follow the uptake and release of fluorescent molecules by living cells while the cells were being incubated with the drug. Erythroleukemia K562 cell lines were used. Our data show that the compounds of these three completely different classes were able to increase the incorporation of pirarubicin provided they had a minimum degree of lipophilicity. Study of the growth inhibitory activity of these compounds revealed that cross-resistance to the tetraalkyl ammonium salt increased with the lipophilicity and was equal to 58 for tetraoctylammonium salt, the most lipophilic compound of this series. This demonstrates that neither the presence of a positive charge nor an aromatic moiety is required for MDR recognition.

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14187-32-7. Chemistry is an experimental science, and the best way to enjoy it and learn about it is performing experiments.Introducing a new discovery about 14187-32-7, Name is Dibenzo-18-crown-6, molecular formula is C20H24O6.

Crown ether complexation of PrCl+2 : Synthesis and structural characterisation of [PrCl2(dibenzo-18-crown-6)(H2o)][SbCl6] ¡¤ 0.5MeOH ¡¤ 0.5MeCN

Treatment of PrCl3(MeCN)3.5 with antimony(V) chloride in the presence of dibenzo-18-crown-6 provided yellow needle crystals of [PrCl2(dibenzo-18-crown-6)(H2O)] [SbCl6] ¡¤ 0.5MeOH ¡¤ 0.5MeCN following recrystallisation of the initial reaction product from boiling CH3OH/CH3CN (50 : 50). The ionic formulation was verified by X-ray crystallography. The cations have crystallographic m symmetry and the metal atoms are nine coordinate involving binding to all six crown oxygen atoms Pr – Ocrown 2.651(11)2.668(10) A, mean 2.658(10) A, two chlorine atoms 2.740(4), 2.749(4) A and a water molecule Pr – OH2O 2.487(10) A. Copyright

14187-32-7, The proportionality constant is the rate constant for the particular unimolecular reaction. the reaction rate is directly proportional to the concentration of the reactant. I hope my blog about 14187-32-7 is helpful to your research.

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14187-32-7. Let¡¯s face it, organic chemistry can seem difficult to learn. Especially from a beginner¡¯s point of view. Like 14187-32-7, Name is Dibenzo-18-crown-6. In a document type is Article, introducing its new discovery.

Stereoselective hydrogenation of dibenzo-18-crown-6 catalyzed by carbon nanotube-supported rhodium nanoparticles

Multiwalled carbon nanotube-supported Rh nanoparticles prepared by a simple sonochemical method are highly active for catalytic hydrogenation of dibenzo-18-crown-6 to dicyclohexyl-18-crown-6. The catalytic hydrogenation reaction shows a selectivity favoring the cis-syn-cis isomer over cis-anti-cis isomer of the product by a factor of ?6. Conventional Rh catalysts supported by activated wood carbon, SiO2, or Al2O3 can only convert dibenzo-18-crown-6 to dicyclohexyl-18-crown-6 with an cis-syn-cis=cis-anti-cis ratio of <1.7. The Rh nanoparticle catalyst can be reused at least six times without losing its catalytic activity. Taylor & Francis Group, LLC. 14187-32-7, I hope this article can help some friends in scientific research. I am very proud of our efforts over the past few months and hope to 14187-32-7, help many people in the next few years.

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14187-32-7. Let¡¯s face it, organic chemistry can seem difficult to learn. Especially from a beginner¡¯s point of view. Like 14187-32-7, Name is Dibenzo-18-crown-6. In a document type is Conference Paper, introducing its new discovery.

New high-dimensional networks based on polyoxometalate and crown ether building blocks

Three novel supramolecular assemblies constructed from polyoxometalate and crown ether building blocks, [(DB18C6)Na(H2O)Na(H2O)1.5] 2Mo6O19¡¤CH3CN, 1, and [{Na(DB18C6)(H2O)2}3 (H2O)2]XMo12O40 ¡¤6DMF¡¤CH3CN (X = P, 2, and As, 3; DB18C6 = dibenzo-18-crown-6; DMF = N,N-dimethylfomamide), have been synthesized and characterized by elemental analyses, IR, UV-vis, EPR, TG, and single crystal X-ray diffraction. Compound 1 crystallizes in the tetragonal space group P4/mbm with a = 16.9701(6) A, c = 14.2676(4) A, and Z = 2. Compound 2 crystallizes in the hexagonal space group P63/m with a = 15.7435(17) A, c = 30.042(7) A, gamma = 120, and Z = 2. Compound 3 crystallizes in the hexagonal space group P63/m with a = 15,6882(5) A, c = 29.9778(18) A, gamma = 120, and Z = 2. Compound 1 exhibits an unusual three-dimensional network with one-dimensional sandglasslike channels based on the extensive weak forces between the oxygen atoms on the [MO6O19]2- polyoxoanions and the CH2 groups of crown ether molecules. Compounds 2 and 3 are isostructural, and both contain a novel semiopen cagelike trimeric cation [{Na(DB18C6)(H2O)2}3 (H2O)2]3+. In their packing arrangement, an interesting 2-D “honeycomblike” “host” network is formed, in which the [XMo12O40]3- (X = As and P) polyoxoanion “guests” resided.

14187-32-7, I hope this article can help some friends in scientific research. I am very proud of our efforts over the past few months and hope to 14187-32-7, help many people in the next few years.

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1,3-Dimesityl-1H-imidazol-3-ium chloride, cas is 141556-45-8, it is a common heterocyclic compound, the chiral-catalyst compound, its synthesis route is as follows.,141556-45-8

General procedure: A mixture of pyrazine ligand 1 or 2 (1mmol), Li2PdCl4 (1mmol) and NaOAc (1mmol) in 20mL of dry methanol was stirred for 24hat rt. The yellow solids (yield: 92%) were collected by filtration and washed several times with methanol, which can be assigned to be palladacyclic dimers. Then, a Schlenk tube was charged with the above chloride-bridged palladacyclic dimers (0.5mmol), the corresponding imidazolium salt (1.25mmol) and tBuOK (2.5mmol) under nitrogen. Dry THF was added by a cannula and stirred at room temperature for 3h. The product was separated by passing through a short silica gel column with CH2Cl2 as eluent, the third band was collected and afforded the corresponding carbene adducts 3-10 as yellow solids. The characterization data for 3: Yield: 78%.

141556-45-8 is used more and more widely, we look forward to future research findings about 1,3-Dimesityl-1H-imidazol-3-ium chloride

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Short Survey; Xu, Chen; Wang, Zhi-Qiang; Yuan, Xiao-Er; Han, Xin; Xiao, Zhi-Qiang; Fu, Wei-Jun; Ji, Bao-Ming; Hao, Xin-Qi; Song, Mao-Ping; Journal of Organometallic Chemistry; vol. 777; (2015); p. 1 – 5;,
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1,3-Dimesityl-1H-imidazol-3-ium chloride, cas is 141556-45-8, it is a common heterocyclic compound, the chiral-catalyst compound, its synthesis route is as follows.,141556-45-8

General procedure: A mixture of pyrazine ligand 1 or 2 (1mmol), Li2PdCl4 (1mmol) and NaOAc (1mmol) in 20mL of dry methanol was stirred for 24hat rt. The yellow solids (yield: 92%) were collected by filtration and washed several times with methanol, which can be assigned to be palladacyclic dimers. Then, a Schlenk tube was charged with the above chloride-bridged palladacyclic dimers (0.5mmol), the corresponding imidazolium salt (1.25mmol) and tBuOK (2.5mmol) under nitrogen. Dry THF was added by a cannula and stirred at room temperature for 3h. The product was separated by passing through a short silica gel column with CH2Cl2 as eluent, the third band was collected and afforded the corresponding carbene adducts 3-10 as yellow solids. The characterization data for 3: Yield: 78%.

141556-45-8 is used more and more widely, we look forward to future research findings about 1,3-Dimesityl-1H-imidazol-3-ium chloride

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Short Survey; Xu, Chen; Wang, Zhi-Qiang; Yuan, Xiao-Er; Han, Xin; Xiao, Zhi-Qiang; Fu, Wei-Jun; Ji, Bao-Ming; Hao, Xin-Qi; Song, Mao-Ping; Journal of Organometallic Chemistry; vol. 777; (2015); p. 1 – 5;,
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It is a common heterocyclic compound, the chiral-catalyst compound, 1,3-Dimesityl-4,5-dihydro-1H-imidazol-3-ium chloride, cas is 173035-10-4 its synthesis route is as follows.,173035-10-4

General procedure: [HIPr]2[PdCl4]: 0.45 g (1.0 mmol) of [HIPr]Cl was added to thesolution of 0.14 g (0.48 mmol) PdCl2(cod) in hot CH3CN (5 mL). Themixture was heated for 15 min, until the yellow solution becamered. The solution was cooled to room temperature and solventwas removed under reduced pressure. The product was precip-itated by addition of diethyl ether (2-3 mL). Product yield: 85%;elemental analysis calcd. (%) for PdCl4C54H78N4: C 62.88, H 7.62,N 5.46; found: C 62.37, H 7.46, N 5.40.1H NMR(500 MHz, CD3CN,25C, TMS): = 8.49 (s, 2H, N CH N); 7.57 (t, J(H,H) = 7.8 Hz, 4H,Ar); 7.42 (d, J(H,H) = 7.8 Hz, 8H, Ar); 4.48 (s, 8H, CH2CH2); 3.10(m, J(H,H) = 6.9 Hz, 8H, CH); 1.40 (d, J(H,H) = 6.9 Hz, 24H, CH3); 1.26(d, J(H,H) = 6.9 Hz, 24H, CH3,);13C NMR (125.75 MHz, CD3CN, 25C,TMS): = 160.0 (N CH N); 147.2 (Ar); 131.0 (Ar); 125.5 (Ar); 53.7(CH2CH2); 28.5 (CH); 24.0 (CH3); 23.5 (CH3).

With the complex challenges of chemical substances, we look forward to future research findings about 1,3-Dimesityl-4,5-dihydro-1H-imidazol-3-ium chloride

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Article; Silarska; Trzeciak; Pernak; Skrzypczak; Applied Catalysis A: General; vol. 466; (2013); p. 216 – 223;,
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Name is 1,3-Dimesityl-4,5-dihydro-1H-imidazol-3-ium chloride, as a common heterocyclic compound, it belongs to chiral-catalyst compound, and cas is 173035-10-4, its synthesis route is as follows.,173035-10-4

Example 38 50.0g of 1,3-Bis-(2,4,6-trimethylphenyl)imidazolinium chloride was added to a 1000 mL single neck round bottom flask containing a Teflon-coated stirbar. 15.2 g of Lithium tert-butoxide (1.3 mol equivalents of Lithium tert-butoxide to 1,3-Bis-(2,4,6-trimethylphenyl)imidazolinium chloride) was added to the 1000 mL flask. 190 mL of anhydrous Hexanes was added to the 1000 mL flask and the flask was capped with a septum and the headspace was purged with argon for 15 minutes with stirring. This mixture was stirred for 2 hours at room temperature. After 2 hours the septum on the 1000 mL flask was replaced with a 250 mL addition funnel. 250 mL of CHCl3 was added to the addition funnel and the funnel was capped with a septum and purged with argon for 5 minutes. After the 250 mL of CHCl3 was added dropwise to the reaction mixture in the 1000 mL flask an additional 130 mL of CHCl3 was added to the addition funnel and the funnel was capped with a septum and purged with argon for 5 minutes. The additional 130 mL of CHCl3 was added dropwise to the reaction mixture in the 1000 mL flask with stirring. A total of 380 mL of CHCl3 was added dropwise to the 1000 mL flask at room temperature under an atmosphere of argon with stirring. Once the 380 mL of CHCl3 was added to the 1000 1 l flask the additional funnel was removed from the flask and the flask was capped with a septum. The headspace of the flask was purged with argon for 15 minutes. The reaction mixture was stirred for 24 hours under an atmosphere of argon to yield an off-white solution. This off-white solution is cooled to 0 C. and then washed with saturated NH4Cl(aq) (4*200 mL) in a separatory funnel at 22-25 C. The organic layer was then washed with saturated NaCl(aq) (2*200 mL) in a separatory funnel at 22-25 C. The organic layer was then placed in a single neck round bottom flask and the excess chloroform was removed in vacuo to yield the crude product as a powdery off-white solid. The off-white solid was washed with a minimal amount of cold methanol (0 C.) and filtered to give 52.5 g of 1,3-dimesityl-2-(trichloromethyl)imidazolidine (62.1 g theoretical yield) as a white to off-white crystalline powder in 85% yield.

With the complex challenges of chemical substances, we look forward to future research findings about 1,3-Dimesityl-4,5-dihydro-1H-imidazol-3-ium chloride

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Patent; Grubbs, Robert H.; Moore, Jason L.; Morgan, John P.; Bell, Andrew; US2003/83445; (2003); A1;,
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As a common heterocyclic compound, it belongs to chiral-catalyst compound, name is 1,3-Dimesityl-1H-imidazol-3-ium chloride, and cas is 141556-45-8, its synthesis route is as follows.,141556-45-8

General procedure: A 20 mL vial was charged with the NHC¡¤HCl (300 mg, 1 equiv.) and the zinc salt (1 equiv.). Tetrahydrofuran (5 mL) was added, the vial was sealed with a screw-cap and the reaction was stirred at 60C for two hours. The mixture was allowed to reach room temperature and the solvent was removed under reduced pressure toafford the desired product.

With the complex challenges of chemical substances, we look forward to future research findings about 1,3-Dimesityl-1H-imidazol-3-ium chloride

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Article; Santoro, Orlando; Nahra, Fady; Cordes, David B.; Slawin, Alexandra M.Z.; Nolan, Steven P.; Cazin, Catherine S.J.; Journal of Molecular Catalysis A: Chemical; vol. 423; (2016); p. 85 – 91;,
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1,3-Dimesityl-1H-imidazol-3-ium chloride, cas is 141556-45-8, it is a common heterocyclic compound, the chiral-catalyst compound, its synthesis route is as follows.,141556-45-8

In a Schlenk flask under argon, to a THF suspension (20 mL) of 1,3-bis(2,4,6-trimethylphenyl)imidazolium chloride (1 g, 2.93 mmol), solid potassium tert-butoxide (0.35 g, 3.12 mmol) was added in a single portion. The mixture was stirred for 45 min at room temperature, and volatiles were removed under vacuum. After addition of THF (20 mL) and stirring for 5 min, the reaction mixture was filtered under argon, and carbon tetrabromide (2.42 g, 5.86 mmol) in THF (10 mL) was added dropwise to solution, over a period of ca. 30 min. The resulting brown solution was stirred for 4 h. Subsequent removal of volatiles in vacuo gave a dark brown residue that was extracted into toluene (10 mL) and then a solution of HCl in dioxane (4 mol/L) was added, and the resulting white precipitate was collected. Yield 351 mg (29%). 1H NMR (500 MHz, DMSO-d6): delta 2.13 (s, 12H, o-CH3), 2.39 (s, 6H, p-CH3), 7.27 (s, 4H, Ar-H), 10.13 (s, 1H, HNCN); 1H NMR (500 MHz, CDCl3): delta 2.20 (s, 6H, p-CH3), 2.54 (s, 12H, o-CH3), 6.82 (s, 4H, Ar-H), 10.16 (s, 1H, HNCN); 13C NMR (125 MHz, DMSO-d6): delta 16.9, 20.7, 113.1, 129.3, 129.6, 135.1, 140.5, 141.7; Elemental analysis calcd. for C21H23Br2ClN2: C 50.58, H 4.65, N 5.62; found C 50.55, H 4.59, N 5.67; ESI-MS (C21H23Br2Cl1N2) (m/z): 497.4 [M]+.

With the rapid development of chemical substances, we look forward to future research findings about 1,3-Dimesityl-1H-imidazol-3-ium chloride

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Article; Amini, Mojtaba; Bagherzadeh, Mojtaba; Rostamnia, Sadegh; Chinese Chemical Letters; vol. 24; 5; (2013); p. 433 – 436;,
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