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Mutarotation methyl glycoside

The two anomers of 3,4,6-tri-0-acetyl-2-deoxy-2-phenylureido-D-glu-cose are unusual in not undergoing mutarotation in aqueous solution, and it is believed that an intra- or inter-molecular chelation prevents mutarotation.168 Both anomers react with methyl iodide-silver oxide to form the methyl /S-D-glycoside, which is also formed from the corresponding n-glu-cosyl bromide on treatment with methanol plus mercuric cyanide. [Pg.255]

The /3-tetraacetate, by etherification of the glycosidic hydroxyl group with methyl iodide and silver oxide, furnished a convenient source for the preparation of methyl tetraacetyl-/3-D-altroside when mutarotation occurred before methylation, considerable methyl tetraacetyl-a-D-altro-side was isolated. The latter was obtained also by rearrangement of the /3-isomer with titanium tetrachloride. These methyl tetraacetylaltro-sides do not contain orthoester linkages, and may be assumed to possess normal pyranoside rings. From the values of - -66.0 and — 61.0°... [Pg.53]

See other pages where Mutarotation methyl glycoside is mentioned: [Pg.22]    [Pg.17]    [Pg.117]    [Pg.19]    [Pg.17]    [Pg.97]    [Pg.1227]    [Pg.492]    [Pg.457]    [Pg.26]    [Pg.24]    [Pg.507]    [Pg.351]    [Pg.18]    [Pg.719]    [Pg.135]    [Pg.120]    [Pg.24]    [Pg.143]    [Pg.270]    [Pg.213]    [Pg.1968]    [Pg.1181]    [Pg.1189]    [Pg.1202]    [Pg.24]    [Pg.719]    [Pg.549]    [Pg.1008]    [Pg.825]    [Pg.1149]    [Pg.33]    [Pg.43]    [Pg.540]    [Pg.27]   
See also in sourсe #XX -- [ Pg.117 , Pg.118 ]



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Glycosides methylation

Methyl glycosides

Methylated Glycosides

Mutarotation

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