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I am interested in disaccarides of D-glucose linked 1-4 style. Anomerization is the interconversion of alpha-D-glucose into beta-D-glucose. I realize that this could only be possible on one of the glucose sub-units: The other glucose is obviously unable to inter-convert due to the glycosidic bond preventing ring-opening.

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I do not see what would prevent it:

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Not only is there no reason to think anomerization does not occur in the disaccharide you mention, it most definitely does occur.

As long as water has access to carbon-1 of a glucose unit, there will be an open-chain form at that site, and then when it re-closes, the possibility of alpha- and beta-anomers. This will be the case for di-, tri- tetra-, oligosaccharides, polysaccharides, etc... and applies to monosaccharides of any carbon length or type (aldoses or ketoses).

The reason is that hemi-acetals or hemi-ketals are intrinsically unstable in water. By contrast, when that carbon is a full acetal or full ketal (a so-called non-reducing sugar) then it is stable in water, and anomerization does not occur. Examples include trehalose and sucrose.

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There is no reason to think that anomerization on the terminal glucose unit does not occur. Although there may be a slight difference in the equilibrium constant between a monosaccharide and a disaccharide due to the change in environment.

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