Methyl ethers triacetate

Key G, di-O-isopropylidene acetal H, methyl ether, triacetate I, oL-tetraacetate. 

Methoxy-6-methyl-2-pyranone (1). Mol. wt. 140.13, m.p. 83-86°. Supplier Aldrich. This ether can be prepared by methylation of triacetic acid lactone (2) with dimethyl sulfate. Exposure of 2 to methyl fluorosulfonate produces the isomeric ether (3). ... 

If no olefins are present, triacetic acid lactone 1 and its methyl ether 21a react photochemically to afford a mixture of compounds without pyrone structure (70CJC237, 70CJC2645). 

The natural pyrone yangonin (10) was synthesized by condensation of triacetic acid lactone methyl ether (8) with p-methoxybenzaldehyde (9) in the presence ol magnesium methoxide (prepared from 200 mg. magnesium and 10 ml. CH lOH)7... 

Oxidation of triacetic lactone methyl ether. The allylic 6-methyl group of triacetic lactone methyl ether (1) is oxidized to a formyl group in high yield by... 

Methylation of Triacetic Acid L.-vctone with Diazomethane in Ether ... 

Fisetol triacetate. 2-(Acetyloxy)-l-[2,4-bis(acetyloxy)phenyl]ethanone, 1385 Flavone. 2-Phenyl-4H-l-benzopyran-4-one, 1334 Fluororesveratrol. a-Fluoro-3, 4,5 -trihydroxystilbene, 1458 Formononetin. 7-Hydroxy-4 -methoxyisoflavone, 1468 Formononetin methyl ether. 7,4 -Dimethoxyisoflavone, 1483 Gallacetophenone. 2, 3, 4 -Trihydroxyacetophenone, 1578, 1613, 1642 Gardenin. 5-Hydroxy-3,6,8,3, 4 5 -hexamethoxyflavone, 1336 Genistein. 5,7,4 -Trihydroxyisoflavone, 1460... 

Methyl tetrahydrofuran Di-n-propyl ether, isopentane (3 1) Glycerol triacetate Ethanol, methanol (4 1 to 1 1) Ethanol, diethyl ether, isopentane (EPA) (2 5 5) (1 4 4)... 

A 5-benzyl-D-ribose has been prepared by Kenner, Taylor and Todd,90 who etherified the methyl 2,3-isopropylidene-D-ribofuranoside (XXI) of Levene and Stiller91 with benzyl chloride to obtain methyl 2,3-iso-propylidene-5-benzyl-D-ribofuranoside (XXII), which was subsequently hydrolyzed to give amorphous 5-benzyl-D-ribose (XXIII). The structure of this ether was confirmed through acetylation to its triacetate (XXIV), hydrogenolysis to 1,2,3-triacetyl-D-ribofuranose (XXV) and further acetylation to the known, crystalline tetraacetyl-D-ribofuranose (XXVI). 

Deuterium-labelled glycogen, III, 246 Dextran, 2,3-dimethyl-D-gIucose from methylated, V, 161 Dextran acetate, II, 218 Dextran beers, IV, 333 Dextran esters, II, 218 Dextran ethers, II, 218 Dextran triacetate, II, 210, 212 Dextran tribenzoate, II, 210, 212 Dextrans... 

Kircher [399] also described the GC analysis of acetals, in addition to the above-mentioned derivatives (see p. 166). He demonstrated the analysis of 4,6-O-ethylidene-D-glucose in the form of the 1,2,3-triacetate on a column packed with completely methylated hydroxyethylcellulose. The diisopropylidene derivative of glucose (retention time ca. 50 min at 200°C) was sufficiently volatile for the analysis and its methyl, ethyl and vinyl ether in the 3-position was even more volatile (retention time 16 min). Mutual separations of these derivatives have not been achieved, however, on this column. 

Diel -AldeT catalyst. Kelly and Montury have examined the effect of three Lewis acids on the Diels-Alder reaction of perf-hydroxylated naphthoquinones with l-methoxy-3-methyl-l,3-butadiene magnesium iodide, boron trifluoride etherate, and boron triacetate. All three increase regioselectivity. BF, etherate and B(OAc)3... 

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