Glucosyl ethers

Phenylethanoid glycosides consist of phenyethyl glucosyl ether, acyl ester (couma-royl, feruroyl and caffeoyl) and glycosyl groups. The structure of isolated phenylethanoid glycosides was determined or identified by comparison with UV, IR, MS... 

Direct etherification of retinol (1) to give retinyl methyl ether (571) was successfully carried out using dimethyl sulfate and n-butyllithium (Hanze et aL, 1948), and this method was also used to prepare a water-soluble retinyl glucosyl ether from retinol (1) (Takabayashi et aL, 1970). 

A number of polyphosphazenes are soluble in water. Examples include polymers with methylamino (39), glucosyl (36), glyceryl (35), or alkyl ether side groups (20). Here, we will consider one example, a polymer that is also well suited to the "clean" method of radiation crossUnking. 

C-Glucosidation. Reaction of the protected a-D-glucopyranosyl chloride 1 with silyl enol ethers activated with AgOTf results in a-C-glucosyl esters or ketones. 

The ether bond between glucosyl and phenyl was cleaved and glucosyl leaves as a tautomer of 2-hydroxyglucal. 

Glucosyl(l 3)rhamnoside Baicalein 7-methyl ether (negletein)... 

Rhamnosylrutinoside) 7-(2 -Glucosylrutinoside) Quercetin 7,3 -dimethyl ether (rhamnazin) 3-Glucosyl(l 5)-a-L-arabinofuranoside Retama sphaerocarpa aerial parts Leguminosae 402... 

Quercetagetin 6,7,3 -trimethyl ether (veronicafolin) 3-Glucosyl(l — 3)galactoside Eupatorium africanum Compositae 23... 

Prenylkaempferol 4 -methyl ether (anhydroicarinin) 7-Glucosyl(l 4)glucoside (cuhuoside, 7-cellobioside) Epimedium acuminatum Berberidaceae 467... 

Di-6"-(acacetin-7-glucosyl)malonate Apigenin 5,7-dimethyl ether... 

By treating 2,3,4,6-tetra-O-acetyl-a-D-glucosyl chloride in ether solution with silver nitrate (Schlubach, Stadtler, Wolf [19]) 2,3,4,6-O-acetyl-a-D-glucosyl nitrate was obtained. 

Preparation of the Pentafluorophenylthionocarbonate 46 The disaccharide 45 [Eq. (19)] (0.1 mmol) was diluted with 1 mL of dry toluene, and (V-hydroxysuccinimide (0.1 mmol) was added. Pentafluorophenyl chlorothionoformate (0.12 mmol) was then added dropwise, and finally anhydrous pyridine (0.5 mmol) was added. The yellow reaction mixture was heated to 80°C until TLC indicated that the reaction was complete. The product was purified by placing the entire reaction mixture on a 2 x 16-cm bed of silica gel and eluting with 4 1 petroleum ether-diethyl ether to give 0-(3,4,6-tri-C>-beiizyl-2-0-[(pentafluorophenoxy)thiocarbonyl]-P-D-glucosyl)-(l— 6)-l,2 3,4-di-0-isopropylidene-a-D-galactopyranose 46 in 77% yield and as a colorless oil [a]D —53.8° (c 0.40, CHClj). 

H. Kunz and W. Sager, Stereoselective glycosylation of alcohols and silyl ethers using glucosyl-fluorides and boron trifluoride etherate, Helv. Chim. Acta 68 283 (1985). 

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