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Ether Cleavage (ether + cleavage)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

p-Methoxybenzyl Ether Cleavage by Polymer-Supported Sulfonamides.

CHEMINFORM, Issue 35 2002
Ronald J. Hinklin
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

Flexible Route to Palmarumycin CP1 and CP2 and CJ-12.371 Methyl Ether

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 23 2010
Karsten Krohn
Abstract The total synthesis of palmarumycin CP1 (4) and CP2 (5) and racemic CJ-12.371 methyl ether (17) is described using the Diels,Alder reaction of benzoquinone 1,8-dihydroxynaphthalene acetal (10) with 1-methoxy-1,3-butadiene under neat reaction conditions. The stereochemistry of adduct 15 was confirmed by single-crystal X-ray analysis. The transformation of 15 into target products 4, 5, and 17 involved dehydrogenation, methyl ether cleavage, and reduction and oxidation steps. [source]

Organoselenium-substituted poly(p -phenylenevinylene)

HETEROATOM CHEMISTRY, Issue 7 2005
Nicolai Stuhr-Hansen
A new type of conjugated polymer, organoselenium substituted poly(p -phenyleneviny- lene) (PPV), was synthesized from the corresponding alkylselenenyl p -xylylene dibromide via a Gilch route using potassium tert -butoxide in THF. The p -xylylene dibromide precursors were synthesized by reacting lithiated bis(methoxymethyl)benzenes with elemental selenium, followed by alkylation of the generated selenolates. As a final demasking step, the bromomethyl functions were liberated by ether cleavage using boron tribromide. Bis-alkylselenenyl PPV was obtained with an average molecular weight Mw of approximately 300,000 g/mol and with polydispersity Mw/Mn = 2. Due to low solubility, monoalkylselenenyl PPV was obtained with a considerably lower average molecular weight in the proximity of 16,000 g/mol and with a polydispersity slightly larger than 3. Absorption and fluorescence spectroscopy revealed that the bis-alkylselenenyl PPV is extensively conjugated. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:656,662, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20167 [source]

Synthesis, Structural Evaluation, and Estrogen Receptor Interaction of 4, 5-Bis(4-hydroxyphenyl)imidazoles

ARCHIV DER PHARMAZIE, Issue 10 2002
Ronald Gust
Abstract 4, 5-Bis(4-hydroxyphenyl)imidazoles with 2, 2,-H (1), 2, 2,-F (2), 2, 2,-Cl (3), and 2, 2,6-Cl (4) substituents in the aromatic rings were synthesized by oxidation of the respective methoxy-substituted (R, S)/(S, R)-4, 5-diaryl-2-imidazolines with MnO2 and subsequent ether cleavage with BBr3. N -alkylation of 1 and 3 with ethyl iodide yielded the compounds 5 and 6. The imidazoles were characterized by NMR spectroscopy and tested for estrogen receptor binding in a competition experiment with [3H]estradiol using calf uterine cytosol. Gene activation was verified in a luciferase assay using estrogen receptor positive MCF-7-2a cells stably transfected with the plasmid EREwtcluc. All halide substituted imidazoles competed with estradiol for the binding site at the estrogen receptor. The N -ethyl derivative 6 showed the highest relative binding affinity of 1.26 %. Treatment of MCF-7-2a cells, however, did not lead to gene activation. The relative activation of 6 amounted only to 10 % at 1,M compared to E2 (100 %). [source]